Objective To explore the feasibility and reference value of allogeneic lung transplantation and postoperative monitoring in miniature pigs for lung transplantation research. Methods Two miniature pigs (R1 and R2) underwent left lung allogeneic transplantation. Complement-dependent cytotoxicity tests and blood cross-matching were performed before surgery. The main operative times and partial pressure of arterial oxygen (PaO₂) after opening the pulmonary artery were recorded during surgery. Postoperatively, routine blood tests, biochemical blood indicators and inflammatory factors were detected, and pathological examinations of multiple organs were conducted. Results The complement-dependent cytotoxicity test showed that the survival rate of lymphocytes between donors and recipients was 42.5%-47.3%, and no agglutination reaction occurred in the cross-matching. The first warm ischemia times of D1 and D2 were 17 min and 10 min, respectively, and the cold ischemia times were 246 min and 216 min, respectively. Ultimately, R1 and R2 survived for 1.5 h and 104 h, respectively. Postoperatively, in R1, albumin (ALB) and globulin (GLB) decreased, and alanine aminotransferase increased; in R2, ALB, GLB and aspartate aminotransferase all increased. Urea nitrogen and serum creatinine increased in both recipients. Pathological results showed that in R1, the transplanted lung had partial consolidation with inflammatory cell infiltration, and multiple organs were congested and damaged. In R2, the transplanted lung had severe necrosis with fibrosis, and multiple organs had mild to moderate damage. The expression levels of interleukin-1β and interleukin-6 increased in the transplanted lungs. Conclusions The allogeneic lung transplantation model in miniature pigs may systematically evaluate immunological compatibility, intraoperative function and postoperative organ damage. The data obtained may provide technical references for subsequent lung transplantation research.

Objective To explore the construction of α-1,3-galactosyltransferase (GGTA1) gene-knockout (GTKO) Diannan miniature pigs and the kidney xenotransplantation from pigs to rhesus macaques, and to assess the effectiveness of GTKO pigs. Methods The GTKO Diannan miniature pigs were constructed using the CRISPR/Cas9 gene-editing system and somatic cell cloning technology. The phenotype of GTKO pigs was verified through polymerase chain reaction, Sanger sequencing and immunofluorescence staining. Flow cytometry was used to detect antigen-antibody (IgM) binding and complement-dependent cytotoxicity. Kidney xenotransplantation was performed from GTKO pigs to rhesus macaques. The humoral immunity, cellular immunity, coagulation and physiological indicators of the recipient monkeys were monitored. The function and pathological changes of the transplanted kidneys were analyzed using ultrasonography, hematoxylin-eosin staining, immunohistochemical staining and immunofluorescence staining. Results Single-guide RNA (sgRNA) targeting exon 4 of the GGTA1 gene in Diannan miniature pigs was designed. The pGL3-GGTA1-sgRNA1-GFP vector was transfected into fetal fibroblasts of Diannan miniature pigs. After puromycin selection, two cell clones, C59# and C89#, were identified as GGTA1 gene-knockout clones. These clones were expanded to form cell lines, which were used as donor cells for somatic cell nuclear transfer. The reconstructed embryos were transferred into the oviducts of trihybrid surrogate sows, resulting in 13 fetal pigs. Among them, fetuses F04 and F11 exhibited biallelic mutations in the GGTA1 gene, and F04 had a normal karyotype. Using this GTKO fetal pig for recloning and transferring the reconstructed embryos into the oviducts of trihybrid surrogate sows, seven surviving piglets were obtained, all of which did not express α-Gal epitope. The binding of IgM from the serum of rhesus monkey 20# to GTKO pig PBMC was reduced, and the survival rate of GTKO pig PBMC in the complement-dependent cytotoxicity assay was higher than that of wild-type pig. GTKO pig kidneys were harvested and perfused until completely white. After the left kidney of the recipient monkey was removed, the pig kidney was heterotopically transplanted. Following vascular anastomosis and blood flow restoration, the pig kidney rapidly turned pink without hyperacute rejection (HAR). Urine appeared in the ureter 6 minutes later, indicating successful kidney transplantation. The right kidney of the recipient was then removed. Seven days after transplantation, the transplanted kidney had good blood flow, the recipient monkey's serum creatinine level was stable, and serum potassium and cystatin C levels were effectively controlled, although they increased 10 days after transplantation. Seven days after transplantation, the levels of white blood cells, lymphocytes, monocytes and eosinophils in the recipient monkey increased, while platelet count and fibrinogen levels decreased. The activated partial thromboplastin time, thrombin time and prothrombin time remained relatively stable but later showed an upward trend. The recipient monkey survived for 10 days. At autopsy, the transplanted kidney was found to be congested, swollen and necrotic, with a small amount of IgG deposition in the renal tissue, and a large amount of IgM, complement C3c and C4d deposition, as well as CD68⁺ macrophage infiltration. Conclusions The kidneys of GTKO Diannan miniature pigs may maintain normal renal function for a certain period in rhesus macaques and effectively overcome HAR, confirming the effectiveness of GTKO pigs for xenotransplantation.

Objective To develop GTKO (α-1,3-galactosyltransferase gene-knockout, GTKO)/hCD55 (human CD55) gene-edited xenotransplant donor pigs and verify their function. Methods In this study, CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 (CRISPR-associated nuclease 9), PiggyBac transposon technology and somatic cell nuclear transfer technology were used to construct GTKO/hCD55 gene-edited Diannan miniature pigs. The phenotype and function of GTKO/hCD55 pigs were analyzed by Sanger sequencing, real-time fluorescence quantitative PCR, flow cytometry, immunofluorescence, bisulfite sequencing, antigen-antibody binding assays, and complement-dependent cytotoxicity assays. Results After transfection of PX458 and PiggyBac gene editing vectors into wild-type fetal pig fibroblasts, 48 single-cell colonies were obtained through puromycin drug screening. Two single-cell colonies were selected for somatic cell nuclear transfer, resulting in two fetal pigs at 33 days of gestation. The GGTA1(α-1,3-galactosyltransferase) genotypes of fetal pig F01 were -17 bp and wild type (WT), while the GGTA1 genotypes of fetal pig F02 were -26 bp/+2 bp and -3 bp. The hCD55 mRNA expression levels of both fetal pigs were significantly higher than those of WT pigs (P＜0.01). The fetal pig F02 was selected as the donor cell source for recloning, 11 surviving piglets were obtained, all identified as GTKO/hCD55 gene-edited pigs. These pigs showed absence of α-Gal antigen expression, but weak or no expression of hCD55 was observed. Methylation analysis of the hCD55 gene's CpG island showed hypermethylation in kidney tissue lacking hCD55 expression, whereas it was not methylated or partially methylated in kidney tissue expressing hCD55. Moreover, codon optimization of the CpG island of the hCD55 gene to reduce CG content could achieve stable expression of the hCD55 gene. In addition, antigen-antibody binding experiment showed that the amount of human IgM binding to GTKO/hCD55 gene-edited pig fibroblasts was significantly lower than that of WT pigs (P＜0.01). Complement-dependent cytotoxicity experiment showed that the survival rate of fibroblasts in GTKO/hCD55 pigs was significantly higher than that in WT pigs (P＜0.01). Conclusion This study demonstrates the successful generation of GTKO/hCD55 gene-edited xenotransplant donor pigs. Methylation-induced gene silencing of the hCD55 gene can be effectively avoided by reducing the CG content of the CpG island through codon optimization. This study provides a reference for the development of xenotransplant donor pigs and guides subsequent research on xenotransplantation.

Lung transplantation is the ultimate therapeutic option for end-stage pulmonary diseases such as interstitial pneumonia, chronic obstructive pulmonary disease and pneumoconiosis. Currently, the shortage of allogeneic lung donors significantly limits the opportunity for end-stage lung disease patients to receive lung transplantation. In recent years, with the rapid development of biomedical engineering technologies, especially the major breakthroughs in genetic modification and cloning, xenogeneic lung transplantation has shown important potential for clinical translation. Among them, genetically modified pigs have become the most promising xenogeneic lung source due to the close similarity of organ size and physiological characteristics to humans, and the ability to perform targeted gene knockouts (such as α-Gal antigen knockout) to reduce the occurrence of hyperacute rejection. This article focuses on the research progress of porcine xenogeneic lung transplantation, systematically reviews the latest achievements and challenges in animal experiments and human trials, and introduces the technical experience accumulated by Shenzhen Third People's Hospital in the porcine-to-monkey xenogeneic lung transplantation model, in the hope of providing practical references for future research in this field.

The accurate segmentation of breast ultrasound images is an important precondition for the lesion determination. The existing segmentation approaches embrace massive parameters, sluggish inference speed, and huge memory consumption. To tackle this problem, we propose T ²KD Attention U-Net (dual-Teacher Knowledge Distillation Attention U-Net), a lightweight semantic segmentation method combined double-path joint distillation in breast ultrasound images. Primarily, we designed two teacher models to learn the fine-grained features from each class of images according to different feature representation and semantic information of benign and malignant breast lesions. Then we leveraged the joint distillation to train a lightweight student model. Finally, we constructed a novel weight balance loss to focus on the semantic feature of small objection, solving the unbalance problem of tumor and background. Specifically, the extensive experiments conducted on Dataset BUSI and Dataset B demonstrated that the T ²KD Attention U-Net outperformed various knowledge distillation counterparts. Concretely, the accuracy, recall, precision, Dice, and mIoU of proposed method were 95.26%, 86.23%, 85.09%, 83.59%and 77.78% on Dataset BUSI, respectively. And these performance indexes were 97.95%, 92.80%, 88.33%, 88.40% and 82.42% on Dataset B, respectively. Compared with other models, the performance of this model was significantly improved. Meanwhile, compared with the teacher model, the number, size, and complexity of student model were significantly reduced (2.2×10 ⁶ vs. 106.1×10 ⁶, 8.4 MB vs. 414 MB, 16.59 GFLOPs vs. 205.98 GFLOPs, respectively). Indeedy, the proposed model guarantees the performances while greatly decreasing the amount of computation, which provides a new method for the deployment of clinical medical scenarios.
Humans ; Breast Neoplasms/diagnostic imaging* ; Female ; Ultrasonography, Mammary/methods* ; Image Processing, Computer-Assisted/methods* ; Algorithms ; Neural Networks, Computer ; Breast/diagnostic imaging*

Objective To cultivate glioblastoma U87 stem-like cells(SLCs)and to detect the level of stemness bio-markers,mitochondrial respiratory capacity and the capacity of in vivo tumorigenesis.Methods B-27,growth factors EGF and bFGF was added into DMEM/F-12 culture in serum-free stem cell culture medium for U87 SLCs.Suspended culture of U87 SLCs was suspended using the neuro-sphere formation assay,while adherent culture of U87 SLCs was achieved by coating Matrigel matrix on the culture surface.The mRNA and protein level of stemness biomarkers in culture were detected using real-time quantitative PCR and Western blot.The proportion of CD133+cells in culture was detected by flow cytometry.The changes of cell oxygen consumption rate were detected by Seahorse cell metabo-lism analysis.Cell tumorigenesis ability was verified by subcutaneous tumor transplantation in animals.Results U87 SLCs in stem cell culture medium would grow into typical sphere morphology within one week,and the spheres would continue to grow as the culture process prolongs.At the appropriate concentration of adhesive,U87 SLCs adhered to and grow well in stem cell culture medium.The mRNA transcription of stemness biomarkers such as CD133,nes-tin,OLIG2,CD44,CD15,and integrin α6(ITGA6)was significantly increased as found in both culture methods,and the protein levels of CD133 and nestin were also increased under both methods(P＜0.05).U87 SLCs showed higher mitochondrial reserve respiratory capacity(P＜0.05).U87 SLCs could form larger subcutaneous tumors with fewer inoculated cells(P＜0.05),and grew faster in vivo with stronger tumorigenic ability.Conclusions U87 SLCs have typical stemness characteristics and may function as tumor cell model with higher stemness properties.

BACKGROUND:Osteoporotic vertebral compression fracture is a common fracture secondary to osteoporosis.At present,there is no effective prediction index and method for osteoporotic vertebral compression fracture. OBJECTIVE:To investigate the predictive effect of the comprehensive index of lumbar vertebral body bone strength on osteoporotic vertebral compression fracture. METHODS:233 patients with osteoporosis were divided into a fracture group and a non-fracture group according to whether a vertebral fracture occurred.The demography,body mass index,vertebral bone mineral density and other details were collected.Lateral X-ray films of the lumbar spine were photographed.The vertebral body width,vertebral body length,sacral slope,pelvic tilt,pelvic incidence,lumbar compressive strength index and the lumbar impact strength index were measured,calculated,and analyzed by univariate and multivariate,and the receiver operating characteristic curve was analyzed.The survival analysis was conducted according to the cut-off value. RESULTS AND CONCLUSION:(1)All patients were followed up for 2-4 years,with an average of 3.1 years.During the follow-up period,99 cases(38 cases of L1 vertebral body,61 cases of L2 vertebral body)had fractures(fracture group),and 134 cases(52 cases of L1 vertebral body,82 cases of L2 vertebral body)had no fractures(non-fracture group).Univariate analysis showed that there was no significant difference in age,sex,height,body mass,body mass index and fracture segment between the two groups(P>0.05).(2)Lumbar compressive strength index and lumbar impact strength index in the fracture group were lower than those in the non-fracture group(P<0.05).Pelvic incidence and pelvic tilt in the fracture group were higher than those in the non-fracture group(P<0.05).(3)Multivariate analysis showed that lumbar compressive strength index,lumbar impact strength index and pelvic tilt were risk factors for osteoporotic vertebral compression fractures(P<0.05).(4)Receiver operating characteristic curve analysis showed that the cutoff values of vertebral bone mineral density,lumbar compressive strength index,lumbar impact strength index,pelvic tilt and pelvic incidence were 0.913 5 g/cm2,1.932,0.903,21.5° and 55°,respectively;areas under the curve were 0.630,0.800,0.911,0.633 and 0.568,respectively.(5)According to the survival analysis(with osteoporotic vertebral compression fracture as the end point),the average survival time of the patients with lumbar impact strength index≥0.903 was significantly longer than that of the patients with lumbar impact strength index<0.903(P<0.05).(6)These findings conclude that the comprehensive index of lumbar vertebral body bone strength is more accurate than the bone mineral density of the vertebral body and spine-pelvis sagittal parameters in predicting osteoporotic vertebral compression fractures,which is helpful for early prevention and treatment of osteoporotic vertebral compression fractures.

BACKGROUND:Osteoporosis vertebral compression fracture is a common fracture secondary to osteoporosis,and there is currently a lack of effective predictive indicators and methods for osteoporosis vertebral compression fracture. OBJECTIVE:To investigate the predictive effects of paravertebral muscle degeneration,functional cross-sectional area,and percentage of fat infiltration on osteoporotic vertebral compression fractures. METHODS:The 224 patients with osteoporosis diagnosed from January 2018 to June 2022 were included.They were followed up for more than 2 years.They were divided into fracture group and non-fracture group according to the presence and absence of vertebral fracture.The detailed information of demographics,body mass index,bone mineral density and so on were collected.The functional cross-sectional area and percentage of fat infiltration of bilateral Psoas major muscle and extensor dorsi(Erector spinae muscles muscle and multifidus muscle)at the level of lower endplate of L2 vertebral body were measured and calculated. RESULTS AND CONCLUSION:(1)224 patients were ultimately included,of which 126 had fractures as the fracture group and 98 had no fractures as the non-fracture group.There was no statistically significant difference in age,gender,height,body mass,body mass index,and fracture segment between the two groups(P>0.05).(2)The bone mineral density of the fracture group was significantly lower than that of the non-fracture group(P<0.05).Functional cross-sectional areas of Psoas major muscle and extensor dorsi in the fracture group were significantly lower than those in the non-fracture group(P<0.05).The percentage of fat infiltration of the extensor dorsi in the fracture group was significantly higher than that in the non-fracture group(P<0.05).There was no significant difference in percentage of fat infiltration of Psoas major muscle between the two groups(P>0.05).(3)Receiver operating characteristic analysis showed that the vertebral bone mineral density,percentage of fat infiltration of extensor dorsi,functional cross-sectional area of extensor dorsi and percentage of fat infiltration of Psoas major muscle were 0.903 g/cm2,35.426%,418.875 mm2,and 6.375%,respectively.The areas under curve were 0.634,0.755,0.876,and 0.585,respectively.(4)These findings indicate that paravertebral muscle degeneration is strongly associated with the occurrence of osteoporotic vertebral compression fractures.The functional cross-sectional area of extensor dorsi muscle can effectively predict the occurrence of osteoporotic vertebral compression fractures,which is helpful for early prevention and treatment of osteoporotic vertebral compression fractures.

BACKGROUND:Bibliometrics and visual analyses based on thematic literature are particularly important for understanding the foundation and frontiers of postmenopausal osteoporosis research. OBJECTIVE:To perform bibliometric,citation,and visualization analyses of highly cited SCI papers in postmenopausal osteoporosis research over the last 20 years. METHODS:The top 100 highly cited papers on postmenopausal osteoporosis published between 2003 and 2022 included in SCI-EXPANDED catalog of the Web of Science database were obtained for bibliometric measure and visual analysis using CiteSpace software. RESULTS AND CONCLUSION:The top 100 highly cited papers have a total of 67 377 citations in the Web of Science Core Collection,with an annual average of 49.17 citations per paper.Postmenopausal osteoporosis research primarily involves medical,engineering,biological,and multidisciplinary fields.The subcategories are dominated by endocrinology and metabolism,and medicine:internal medicine.Stable and close cooperative network relationships have been formed globally.United States,University of California System,Cummings,and Steven R are the country,research institution,and author,respectively,with the most highly-cited publications.The frontiers of postmenopausal osteoporosis research mainly include calcium and vitamin D supplementation and fracture risk,clinical studies of bisphosphonates in the treatment of postmenopausal osteoporosis,atypical femur fracture,clinical studies of new drugs and sequential treatment of postmenopausal osteoporosis,predictors of fracture risk,mid-and long-term follow-up of osteoporotic vertebral compression fractures,genetic polymorphisms and hereditary factors,formulation and updating of clinical practice guidelines for postmenopausal osteoporosis.Large cohort studies,high-quality randomized controlled trials,systematic reviews,meta-analyses,and clinical practice guidelines are the great engines that drive the development of clinical research in postmenopausal osteoporosis.We should make efforts in the above areas to improve China's international influence in the field of osteoporosis.

On August 2-4,2023,the"Third Summit Forum on'Building a Community of Shared Future for Doctors and Patients'"was jointly organized by institutions such as the Chinese Medical Ethics,the Hospital Humanities Management and Talent Training Special Committee of the China Population and Culture Promotion Association,Center for Ethical Studies of Renmin University of China,the Newspaper for China's Physicians,the China Health Law Society,the China Anti-Cancer Association,and the China Association For Ethical Studies in Harbin.The conference arranged a sub-forum for the"Seminar on the Construction of Chinese Medical Humanities",with domestic medical humanities scholars attending the conference.After heated discussions at the seminar,the Scholars'Consensus on the Construction and Development of Chinese Medical Humanities was formed.It was proposed that in the new era,it is urgent to build the medical humanities discipline,as well as lead the academic integration and development of medical humanities under the core socialist values.At the same time,for the construction of the medical humanities discipline,it is necessary to optimize the organizational mechanism,prosper and develop the overall framework of the medical humanities discipline,accelerate the construction of a professional teaching team for the medical humanities discipline,promote the establishment of a new carrier medical humanities education and teaching in cultivating morality and nurturing talents,as well as focus on solving problems related to the cultivation of medical humanities graduate students.