Scientific principle is the cornerstone of the development and construction of a discipline. In the current chaotic situation in the field of plastic surgery, it is particularly necessary to clarify the scientific principle of plastic surgery. Following the definitions of scientific principle, discipline, and profession, this article sorts out the differences between plastic surgery and other surgeries from different perspectives such as anatomical site, treatment scope, disease type, and professional technology; summarizes the essential characteristics of plastic surgery from its origin, artistic and philosophical attributes, medical and ethical norms, and the basic principles; revises the definition of plastic surgery; clarifies that cosmetic surgery is a branch of plastic surgery from the aspects of treatment objects, goals, technical means, interdisciplinary intersections, and medical regulations. Through the demonstration of multiple dimensions of medicine and sociology, the scientific principle that embodies the essential attributes of plastic surgery is summarized: under medical and ethical regulations, the morphological and functional needs of the human body are converted to feasible medical practices by tissue structure reshaping.

Scientific principle is the cornerstone of the development and construction of a discipline. In the current chaotic situation in the field of plastic surgery, it is particularly necessary to clarify the scientific principle of plastic surgery. Following the definitions of scientific principle, discipline, and profession, this article sorts out the differences between plastic surgery and other surgeries from different perspectives such as anatomical site, treatment scope, disease type, and professional technology; summarizes the essential characteristics of plastic surgery from its origin, artistic and philosophical attributes, medical and ethical norms, and the basic principles; revises the definition of plastic surgery; clarifies that cosmetic surgery is a branch of plastic surgery from the aspects of treatment objects, goals, technical means, interdisciplinary intersections, and medical regulations. Through the demonstration of multiple dimensions of medicine and sociology, the scientific principle that embodies the essential attributes of plastic surgery is summarized: under medical and ethical regulations, the morphological and functional needs of the human body are converted to feasible medical practices by tissue structure reshaping.

Objective:To investigate the effect of the transfer of blastocysts that have not re-expanded after 2-4 h of thawing on pregnancy and neonatal outcomes.Methods:A retrospective cohort study was performed to analyze the clinical data from 2 428 vitrified frozen-thawed single blastocyst transfer cycles at the Reproductive Medicine Center of the 901st Hospital of the Joint Logistics Support Force of PLA between January 2015 and March 2024. Based on the re-expansion status of the blastocoel cavity after thawing, the cycles were divided into group A (110 non-re-expanded) and group B (2 318 re-expanded). After propensity score matching, there were 109 cycles in each group. Pregnancy and neonatal outcomes between the two groups were compared.Results:Before propensity score matching, there were statistical differences in percentage of good-quality blastocyst transfer, percentage of degree 4 blastocyst, percentage of endometriosis and others in reasons for infertility between the two groups (all P<0.05). After propensity score matching, there were no statistical differences in baseline characteristics between the two groups (all P>0.05). The clinical pregnancy rate [27.52% (30/109)], the ongoing pregnancy rate [21.10% (23/109)] and the live birth rate [19.27% (21/109)] in group A were all significantly lower than those in group B [61.47% (67/109), 51.38% (56/109), 47.70% (52/109), all P<0.001]. Neonatal outcomes showed no statistically significant differences between the two groups in terms of birth weight, neonatal length, malformation rate, monozygotic twin rate and male neonatal rate (all P>0.05). Conclusion:Transfer of non-re-expanded blastocysts after thawing may reduce clinical pregnancy rate but does not negatively affect neonatal outcomes.

AIM:We investigated the survival,migration and differentiation abilities of human oligodendro-cyte precursor cells(hOPC)in the brains of mice with vascular dementia(VaD),the effects of hOPC on cerebral white matter,and the underlying mechanisms.METHODS:Mouse VaD model was constructed using the bilateral common ca-rotid artery stenosis method,and the mice were randomly divided into sham,VaD and hOPC groups.Eight weeks after model establishment,the mice in VaD and hOPC groups received equal volume of vehicle(PBS)and hOPC solution,re-spectively,through the corpus callosum.Survival,migration and differentiation of hOPC in the brain were observed by im-munofluorescence staining at 4 and 12 weeks after transplantation.Twelve weeks after transplantation,the effects of hOPC on mouse brain white matter were detected by immunofluorescence staining of myelin basic protein(MBP),myelin-associ-ated glycoprotein(MAG),neurofilament protein 200(NF200)and non-phosphorylated neurofilament H(using monoclo-nal antibody SMI32),and by water maze experiments.Paracrine signaling by hOPC was explored using immunofluores-cence staining for vascular endothelial growth factor(VEGF).RESULTS:The hOPC survived in the brains of VaD mice for 12 weeks,migrated to damaged white matter areas,and partially differentiated into mature oligodendrocytes(approxi-mately 64%).Twelve weeks after transplantation,hOPC significantly increased the fluorescence intensity of MBP,MAG,and NF200(P<0.05 or P<0.01)and decreased the fluorescence intensity of SMI32(P<0.01).The VEGF expression in hOPC-treated mice was significantly higher than that in sham and VaD groups(P<0.01).The difference in water maze test performance between hOPC and sham groups was not statistically significant(P>0.05).The mice in hOPC group had a shorter latency than those in VaD group(P<0.05 or P<0.01),and performed more platform crossings than those in VaD group(P<0.05).CONCLUSION:The hOPC can survive,migrate and differentiate in the brains of VaD mice,attenuate cerebral white matter lesions,and improve cognitive function.These improvements may be attributed to cell replacement and paracrine effects.

Objective:To investigate the effect of the transfer of blastocysts that have not re-expanded after 2-4 h of thawing on pregnancy and neonatal outcomes.Methods:A retrospective cohort study was performed to analyze the clinical data from 2 428 vitrified frozen-thawed single blastocyst transfer cycles at the Reproductive Medicine Center of the 901st Hospital of the Joint Logistics Support Force of PLA between January 2015 and March 2024. Based on the re-expansion status of the blastocoel cavity after thawing, the cycles were divided into group A (110 non-re-expanded) and group B (2 318 re-expanded). After propensity score matching, there were 109 cycles in each group. Pregnancy and neonatal outcomes between the two groups were compared.Results:Before propensity score matching, there were statistical differences in percentage of good-quality blastocyst transfer, percentage of degree 4 blastocyst, percentage of endometriosis and others in reasons for infertility between the two groups (all P<0.05). After propensity score matching, there were no statistical differences in baseline characteristics between the two groups (all P>0.05). The clinical pregnancy rate [27.52% (30/109)], the ongoing pregnancy rate [21.10% (23/109)] and the live birth rate [19.27% (21/109)] in group A were all significantly lower than those in group B [61.47% (67/109), 51.38% (56/109), 47.70% (52/109), all P<0.001]. Neonatal outcomes showed no statistically significant differences between the two groups in terms of birth weight, neonatal length, malformation rate, monozygotic twin rate and male neonatal rate (all P>0.05). Conclusion:Transfer of non-re-expanded blastocysts after thawing may reduce clinical pregnancy rate but does not negatively affect neonatal outcomes.

AIM:We investigated the survival,migration and differentiation abilities of human oligodendro-cyte precursor cells(hOPC)in the brains of mice with vascular dementia(VaD),the effects of hOPC on cerebral white matter,and the underlying mechanisms.METHODS:Mouse VaD model was constructed using the bilateral common ca-rotid artery stenosis method,and the mice were randomly divided into sham,VaD and hOPC groups.Eight weeks after model establishment,the mice in VaD and hOPC groups received equal volume of vehicle(PBS)and hOPC solution,re-spectively,through the corpus callosum.Survival,migration and differentiation of hOPC in the brain were observed by im-munofluorescence staining at 4 and 12 weeks after transplantation.Twelve weeks after transplantation,the effects of hOPC on mouse brain white matter were detected by immunofluorescence staining of myelin basic protein(MBP),myelin-associ-ated glycoprotein(MAG),neurofilament protein 200(NF200)and non-phosphorylated neurofilament H(using monoclo-nal antibody SMI32),and by water maze experiments.Paracrine signaling by hOPC was explored using immunofluores-cence staining for vascular endothelial growth factor(VEGF).RESULTS:The hOPC survived in the brains of VaD mice for 12 weeks,migrated to damaged white matter areas,and partially differentiated into mature oligodendrocytes(approxi-mately 64%).Twelve weeks after transplantation,hOPC significantly increased the fluorescence intensity of MBP,MAG,and NF200(P<0.05 or P<0.01)and decreased the fluorescence intensity of SMI32(P<0.01).The VEGF expression in hOPC-treated mice was significantly higher than that in sham and VaD groups(P<0.01).The difference in water maze test performance between hOPC and sham groups was not statistically significant(P>0.05).The mice in hOPC group had a shorter latency than those in VaD group(P<0.05 or P<0.01),and performed more platform crossings than those in VaD group(P<0.05).CONCLUSION:The hOPC can survive,migrate and differentiate in the brains of VaD mice,attenuate cerebral white matter lesions,and improve cognitive function.These improvements may be attributed to cell replacement and paracrine effects.

Breast augmentation using polyacrylamide hydrogel (PAHG) was widely used in China. We present the first case of delayed breast inflammation after 2019 novel coronavirus(2019-nCoV) infection in a patient who recieved breast augmentation with PAHG 20 years ago, without any other predispositions. The 45-year-old female patient complained of severe breast swelling and pain three weeks after 2019-nCoV infection. The swelling extended from the upper clavicle to the upper abdomen. Delayed inflammation reaction was diagnosed, followed by emergency surgery. During the surgery, the injected material was observed to gush out in a form of greenish and thin paste, with a foul odor. The wound had extensive diffuse oozing and hemoglobin decreased significantly. The patient was discharged one week after surgery. During a three-month follow-up, she experienced weakness and fatigue with no complications. There are still many unknown areas of the impact of 2019-nCoV on human foreign bodies and immune system, which is diverse and complex. Reporting various possible symptoms and mechanisms is conducive to improving the level of awareness and intervention of plastic surgeons.

Breast augmentation using polyacrylamide hydrogel (PAHG) was widely used in China. We present the first case of delayed breast inflammation after 2019 novel coronavirus(2019-nCoV) infection in a patient who recieved breast augmentation with PAHG 20 years ago, without any other predispositions. The 45-year-old female patient complained of severe breast swelling and pain three weeks after 2019-nCoV infection. The swelling extended from the upper clavicle to the upper abdomen. Delayed inflammation reaction was diagnosed, followed by emergency surgery. During the surgery, the injected material was observed to gush out in a form of greenish and thin paste, with a foul odor. The wound had extensive diffuse oozing and hemoglobin decreased significantly. The patient was discharged one week after surgery. During a three-month follow-up, she experienced weakness and fatigue with no complications. There are still many unknown areas of the impact of 2019-nCoV on human foreign bodies and immune system, which is diverse and complex. Reporting various possible symptoms and mechanisms is conducive to improving the level of awareness and intervention of plastic surgeons.

Objective To establish the analysis method of 13 Paralytic shellfish toxins(PSTs)in human whole blood by high-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).Methods 13 kinds of PSTs were extracted from the whole blood using acetonitrile with 1%acetate(1︰3,v︰v)solution,and separated by UPLC BEH Amide chromatographic column(100mm×2.1mm,1.7μm).The samples were detected by an electrospray ionization source(ESI)and positive and negative ion multiple reaction monitoring(MRM)mode,and quantified by matrix matching curve external standard method.Results The results showed that 13 kinds of PSTs in blood samples were linear well in the ranges of 1～100 ng/mL,with the correlation coefficient(r2)>0.995.The limit of detection(LODs)of the method were 0.5～2 ng/mL,the limit of quantitation(LOQs)were 1～4 ng/mL,and the recoveries of the method were 65.55%～114.12%.Conclusion The method is highly sensitive,reproducible,and can qualify and quantify thirteen toxins at the same time,which is suitable for the rapid detection of PSTs in whole blood samples.