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Objective:To investigate the combination of internal fixation for periprosthetic fractures of the proximal femur (PFFF) after hip arthroplasty.Methods:The data of 58 patients with periprosthetic fractures after hip arthroplasty from May 2008 to March 2022 were retrospectively analyzed, including 31 males and 27 females. The average age was 75.5±18.2 years (range, 35-95 years). There were 39 total hip arthroplasty and 19 hemiarthroplasty; 37 biological prosthesis and 21 cemented prosthesis. Intraoperative periprosthetic fractures occurred in 6 cases and 52 cases postoperatively. Unified classification system (UCS): UCS IV.3A1 type 2 cases, 3A2 type 1 case, 3B1.1 type 19 cases, 3B2.1 type 25 cases, 3B3 type 2 cases, 3C type 9 cases. Fracture site: 3 cases in zone A (greater trochanter), 46 cases in zone B (around the femoral stem), and 9 cases in zone C (distal to the tip of the femoral stem. Internal fixation is composed of primary and secondary fixation, the main fixation method was the cerclage of steel wire or titanium cable, locking compression plate, and locking attachment plate fixation. The secondary fixation method was the cerclage of titanium cable, which was required to cover three zones A, B and C to form an overall balanced fixation. The modified Harris hip scores (mHHS), plate length, working length and screw number of different internal fixation combinations were compared.Results:The follow-up time was 54.2±21.6 months (range, 11-86 months). All patients showed signs of fracture healing at 10.2±1.5 weeks (range, 7-13 weeks) after operation, and bony union was observed at 19.6±1.3 weeks (range, 17-22 weeks) after operation. No delayed union or nonunion was observed. After operation, one case had a stress fracture and was revised with double-plate internal fixation; one case had a failed internal fixation and was revised with double-plate internal fixation and a large allograft bone graft. The mHHS score of UCSIV.3B2.1 group (80.3±4.6) was the lowest at 6 months after operation, and the difference between the groups of different types was statistically significant ( F=256.72, P<0.001). The score of simple internal fixation group (91.6±4.2) was higher than that of revision combined with internal fixation group (81.9±4.1), and the difference was statistically significant ( t=8.32, P<0.001). The plate length and working length were 24.9±2.5 cm and 12.6±1.7 cm for UCS IV.3B1.1, 25.4±2.6 cm and 13.6±1.8 cm for 3B2.1 and 28.1±2.5 cm and 4.9±1.9 cm for 3C, respectively ( F=5.33, P=0.005; F=6.78, P<0.001). The number of screws in zone A was significant difference among different UCS types ( F=52.67, P<0.001); UCS IV.3B1.1 (6.5±2.3) and 3B2.1 (6.7±2.2) were more than 3B3 (3.5±1.5) and 3C (3.7±1.6). The number of screws in zone B was significant difference among different UCS types ( F=42.15, P<0.001); The number of UCS IV.3B1.1 (2.3±1.6) and 3B2.1 (2.8±1.9) were significantly more than that of 3B3 (1.0±0.5) and 3C (1.2±0.6). The number of screws in zone C was significant differences among different UCS types ( F=39.62, P<0.001); The number of UCS IV.3B1.1 (3.8±1.9) and 3B2.1 (3.9±1.7) were more than that of 3B3 (2.0±0.5), the difference was statistically significant ( P<0.05). Conclusion:The function of hip after simple internal fixation of proximal femoral periprosthetic fractures was better than that of those who underwent revision at the same time; the number of screws of UCSIV.B1 and B2 is more than that of B3.
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COVID-19 is caused by coronavirus SARS-CoV-2. Current systemic vaccines generally provide limited protection against viral replication and shedding within the airway. Recombinant VSV (rVSV) is an effective vector which inducing potent and comprehensive immunities. Currently, there are two clinical trials investigating COVID-19 vaccines based on VSV vectors. These vaccines were developed with spike protein of WA1 which administrated intramuscularly. Although intranasal route is ideal for activating mucosal immunity with VSV vector, safety is of concern. Thus, a highly attenuated rVSV with three amino acids mutations in matrix protein (VSVMT) was developed to construct safe mucosal vaccines against multiple SARS-CoV-2 variants of concern. It demonstrated that spike protein mutant lacking 21 amino acids in its cytoplasmic domain could rescue rVSV efficiently. VSVMT indicated improved safeness compared with wild-type VSV as the vector encoding SARS-CoV-2 spike protein. With a single-dosed intranasal inoculation of rVSVΔGMT-SΔ21, potent SARS-CoV-2 specific neutralization antibodies could be stimulated in animals, particularly in term of mucosal and cellular immunity. Strikingly, the chimeric VSV encoding SΔ21 of Delta-variant can induce more potent immune responses compared with those encoding SΔ21 of Omicron- or WA1-strain. VSVMT is a promising platform to develop a mucosal vaccine for countering COVID-19.
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Developing universal CARs with improved flexible targeting and controllable activities is urgently needed. While several studies have suggested the potential of CD16a in tandem with monoclonal antibodies to construct universal CAR-T cells, the weak affinity between them is one of the limiting factors for efficacy. Herein, we systematically investigated the impact of Fcγ receptor (FcγR) affinity on CAR-T cells properties by constructing universal CARs using Fcγ receptors with different affinities for IgG1 antibodies, namely CD16a, CD32a, and CD64. We demonstrated that the activities of these universal CAR-T cells on tumor cells could be redirected and regulated by IgG1 antibodies. In xenografted mice, 64CAR chimeric Jurkat cells with the highest affinity showed significant antitumor effects in combination with herceptin in the HER2 low expression U251 MG model. However, in the CD20 high expression Raji model, 64CAR caused excessive activation of CAR-T cells, which resulted in cytokine release syndrome (CRS) and the decline of antitumor activity, and 32CAR with a moderate affinity brought the best efficacy. Our work extended the knowledge about FcγR-based universal CAR-T cells and suggested that only the FcγRCAR with an appropriate affinity can offer the optimal antitumor advantages of CAR-T cells.
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The continuous emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants poses challenges to the effectiveness of neutralizing antibodies. Rational design of antibody cocktails is a realizable approach addressing viral immune evasion. However, evaluating the breadth of antibody cocktails is essential for understanding the development potential. Here, based on a replication competent vesicular stomatitis virus model that incorporates the spike of SARS-CoV-2 (VSV-SARS-CoV-2), we evaluated the breadth of a number of antibody cocktails consisting of monoclonal antibodies and bispecific antibodies by long-term passaging the virus in the presence of the cocktails. Results from over two-month passaging of the virus showed that 9E12+10D4+2G1 and 7B9-9D11+2G1 from these cocktails were highly resistant to random mutation, and there was no breakthrough after 30 rounds of passaging. As a control, antibody REGN10933 was broken through in the third passage. Next generation sequencing was performed and several critical mutations related to viral evasion were identified. These mutations caused a decrease in neutralization efficiency, but the reduced replication rate and ACE2 susceptibility of the mutant virus suggested that they might not have the potential to become epidemic strains. The 9E12+10D4+2G1 and 7B9-9D11+2G1 cocktails that picked from the VSV-SARS-CoV-2 system efficiently neutralized all current variants of concern and variants of interest including the most recent variants Delta and Omicron, as well as SARS-CoV-1. Our results highlight the feasibility of using the VSV-SARS-CoV-2 system to develop SARS-CoV-2 antibody cocktails and provide a reference for the clinical selection of therapeutic strategies to address the mutational escape of SARS-CoV-2.
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Numerous mutations in the spike protein of SARS-CoV-2 B.1.1.529 Omicron variant pose a crisis for antibody-based immunotherapies. The efficacy of emergency use authorized (EUA) antibodies that developed in early SARS-CoV-2 pandemic seems to be in flounder. We tested the Omicron neutralization efficacy of an early B cell antibody repertoire as well as several EUA antibodies in pseudovirus and authentic virus systems. More than half of the antibodies in the repertoire that showed good activity against WA1/2020 previously had completely lost neutralizing activity against Omicron, while antibody 8G3 displayed non-regressive activity. EUA antibodies Etesevimab, Casirivimab, Imdevimab and Bamlanivimab were entirely desensitized by Omicron. Only Sotrovimab targeting the non-ACE2 overlap epitope showed a dramatic decrease activity. Antibody 8G3 efficiently neutralized Omicron in pseudovirus and authentic virus systems. The in vivo results showed that Omicron virus was less virulent than the WA1/2020 strain, but still caused deterioration of health and even death in mice. Treatment with 8G3 quickly cleared virus load of mice. Antibody 8G3 also showed excellent activity against other variants of concern (VOCs), especially more efficient against authentic Delta plus virus. Collectively, our results suggest that neutralizing antibodies with breadth remains broad neutralizing activity in tackling SARS-CoV-2 infection despite the universal evasion from EUA antibodies by Omicron variant.
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Emerging SARS-CoV-2 variants are threatening the efficacy of antibody therapies. Combination treatments including ACE2-Fc have been developed to overcome the evasion of neutralizing antibodies (NAbs) in individual cases. Here we conducted a comprehensive evaluation of this strategy by combining ACE2-Fc with NAbs of diverse epitopes on the RBD. NAb+ACE2-Fc combinations efficiently neutralized HIV-based pseudovirus carrying the spike protein of the Delta or Omicron variants, achieving a balance between efficacy and breadth. In an antibody escape assay using replication-competent VSV-SARS-CoV-2-S, all the combinations had no escape after fifteen passages. By comparison, all the NAbs without combo with ACE2-Fc had escaped within six passages. Further, the VSV-S variants escaped from NAbs were neutralized by ACE2-Fc, revealing the mechanism of NAb+ACE2-Fc combinations survived after fifteen passages. We finally examined ACE2-Fc neutralization against pseudovirus variants that were resistant to the therapeutic antibodies currently in clinic. Our results suggest ACE2-Fc is a universal combination partner to combat SARS-CoV-2 variants including Delta and Omicron.
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Esophageal cancer is one of the top ten of the world's most common cancer. Although the incidence of esophageal squamous cell carcinoma (ESCC) in some high-risk areas in East Asia has being decreasing, it is still the most common histologic subtypes. A great many of patients with ESCC not only are diagnosed in an advanced stage but also have a high mortality rate. With the application of tumor immunotherapy in ESCC treatment in recent years, the prognosis of ESCC patients has been improved to a certain extent. This article intends to review the research progress of immunotherapy in esophageal squamous cell carcinoma.
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Objective:To investigate the features of endoscopic ultrasonography in the diagnosis of malignant mediastinal and abdominal lymphadenopathy and to provide more evidence for endoscopic ultrasound-guided fine-needle aspiraiton (EUS-FNA).Methods:A case-control study was performed on 83 consecutive patients who underwent EUS in the Second Affiliated Hospital of Soochow University from September 2016 to February 2021. Lymph node properties were identified by pathological results of EUS-FNA and (or) surgery and follow-up for at least 6 months. According to the final diagnosis, patients were divided into malignant lymph node group ( n=56) and benign lymph node group ( n=27). Univariate analysis and multivariate logistic analysis were performed to identify independent risk factors for malignant lymphadenopathy in terms of EUS features. Results:Univariate analysis showed that the length of short axis, short-long axis ratio, shape, border, presence or absence of hilum, heterogeneous echo, and the growth pattern of lymph node were risk factors for malignant lymph nodes ( P<0.10). Multivariate logistic regression analysis showed that short axis>10 mm ( P=0.021, OR=9.751, 95% CI: 1.407-57.573), clear border ( P=0.009, OR=20.587, 95% CI: 2.149-197.251), absence of hilum ( P=0.019, OR=28.502, 95% CI: 1.725-470.864), nodal matting ( P=0.004, OR=45.539, 95% CI: 3.429-604.822), partial nodal fusion ( P=0.004, OR=50.012, 95% CI: 3.497-715.266) were independent risk factors for malignant mediastinal and abdominal lymph nodes. Conclusion:EUS is useful to differentiate the lymph node properties in the mediastinal or abdominal cavity. Short axis>10 mm, clear border, absence of hilum, nodal matting and partial nodal fusion are high-risk EUS features of malignant mediastinal or abdominal lymphadenopathy, where priority should be given to EUS-FNA.
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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) continue to wreak havoc across the globe. Higher transmissibility and immunologic resistance of VOCs bring unprecedented challenges to epidemic extinguishment. Here we describe a monoclonal antibody, 2G1, that neutralizes all current VOCs and has surprising tolerance to mutations adjacent to or within its interaction epitope. Cryo-electron microscopy structure showed that 2G1 bound to the tip of receptor binding domain (RBD) of spike protein with small contact interface but strong hydrophobic effect, which resulted in nanomolar to sub-nanomolar affinities to spike proteins. The epitope of 2G1 on RBD partially overlaps with ACE2 interface, which gives 2G1 ability to block interaction between RBD and ACE2. The narrow binding epitope but high affinity bestow outstanding therapeutic efficacy upon 2G1 that neutralized VOCs with sub-nanomolar IC50 in vitro. In SARS-CoV-2 and Beta- and Delta-variant-challenged transgenic mice and rhesus macaque models, 2G1 protected animals from clinical illness and eliminated viral burden, without serious impact to animal safety. Mutagenesis experiments suggest that 2G1 could be potentially capable of dealing with emerging SARS-CoV-2 variants in future. This report characterized the therapeutic antibodies specific to the tip of spike against SARS-CoV-2 variants and highlights the potential clinical applications as well as for developing vaccine and cocktail therapy.
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Objective:To investigate the expression, regulation, potential mechanism and clinical significance of microRNA(miRNA)-129-1 in colon cancer.Methods:The changes of expression and methylation of miRNA-129-1 were analyzed from the methylation, mRNA expression and miRNA expression data of colon cancer in the cancer genome atlas (TCGA) database. The target genes of miRNA-129-1 were predicted from miRwalk 2.0 and TargetScan database. DAVID 6.7 online software was used for gene oncology and Kyoto encyclopedia of genes and genomes enrichment analysis. STRING database was used for protein-protein interaction analysis. TCGA data were applied again to analyze the differential expression and prognosis of key target genes of miRNA-129-1. Paired t test and independent sample t test were used for statistical analysis. The receiver operating characteristic curve (ROC) was used to evaluate the diagnostic value of miRNA-129-1 gene methylation in colon cancer. Kaplan-Meier method and log-rank test were used to analyze the effects of miRNA-129-1 expression on survival. Results:The sequence of miRNA-129-1 among different species was conserved. After all colon cancer samples, and control samples of TCGA database were analyzed, the results showed that compared with those of control samples, the expression of miRNA-129-1 decreased in cancer samples (0.98±0.81 vs. 5.74±0.59), and the methylation levels of cg04524088, cg04840800, cg11364290, cg20734982 and cg24044186 locus of miRNA-129-1 significantly decreased (0.321±0.130 vs. 0.563±0.051, 0.432±0.123 vs. 0.624±0.064, 0.475±0.153 vs. 0.768±0.033, 0.659±0.180 vs. 0.816±0.037 and 0.862±0.096 vs. 0.916±0.019, respectively) in colon cancer tissues, and the differences were all statistically significant ( t=14.95, 11.36, 9.39, 11.74, 5.32 and 3.47, all P<0.01). The results of ROC analysis showed that the methylation levels of the above five locus of miRNA-129-1 gene had high diagnostic efficiency in colon cancer (area under curve=0.946, 0.915, 0.950, 0.758 and 0.667, all P<0.01). The results of survival analysis indicated that low expression of miRNA-129-1 was associated with poor prognosis (hazard ratio ( HR)=0.55, P=0.018). The results of bioinformatics analysis demonstrated that the target genes of miRNA-129-1 were enriched in serine / threonine kinase receptor, mitogen-activated protein kinase and other functional gene clusters closely related to tumor, and there was a complex interaction network among the target genes proteins. The high expression of ephrin type-B receptor2 ( EPHB2) gene, a potential key target gene of miRNA-129-1, was associated with the short overall survival and disease-free survival time ( HR=1.9 and 1.6, both P<0.01). Conclusions:The expression and methylation of miRNA-129-1 play an important regulatory role in the development and development of colon cancer. The methylation of miRNA-129-1 has potential value in the diagnosis of colon cancer, and miRNA-129-1 is an influencing factor for the prognosis of patients with colon cancer. EPHB2 may be a potential key target gene of miRNA-129-1.
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@#Targeted programmed death-ligand 1 (PD-L1) and CXC chemokine receptor type 4 (CXCR4), gene sequences encoding anti-PD-L1 nanobody and anti-CXCR4 nanobody were cloned into the pET-22b (+) vector to construct recombinant expression plasmid of anti-PD-L1&CXCR4 bispecific nanobody, which was connected with 6 × His tag and transformed into E.coli BL21 (DE3). The expressed proteins were then found to exist as a soluble form in the supernatant of bacterial lysate after induction of IPTG.Three purification methods were used to obtain the target protein in order to improve the yield and purity of the bispecific nanobody.The bacterial supernatant was separated and purified by His Trap FF affinity chromatographic column.The target protein output could exceed 1 mg/L, and the product purity could reach up to 97%.Besides, the anti-PD-L1&CXCR4 bispecific nanobody shows a specific binding ability to two antigens on the cell surface, enhancing the cytotoxicity of IL-2 activated human peripheral blood mononuclear cells (PBMC) to tumor cell line AsPC-1, which lays the foundation for further evaluation of its drug efficacy in vivo.
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ImportanceThe healthcare demand created by the COVID-19 pandemic was far beyond the hospital surge capacity in many countries, resulting in possible negative influence on prognosis of other severe diseases, such as cardiovascular disease (CVD). ObjectiveTo assess the impact of the COVID-19 outbreak on CVD-related hospitalizations and mortality. DesignCommunity-based prospective cohort study. Setting the UK Biobank population. Participants421,717 UK Biobank participants who were registered in England and alive on December 1st 2019. Main outcomes and measuresThe primary outcome of interest was CVD death, as deaths with CVD as a cause of death according to the death registers. We retrieved information on hospitalizations with CVD as the primary diagnosis based on the UK Biobank hospital inpatient data. The study period was between December 1st 2019 and May 30th 2020, and we used the same calendar period of the three preceding years as the reference period. Standardized mortality/incidence ratios (SMRs/SIRs) with 95% confidence intervals were used to estimate the relative risk of CVD outcomes during the study period, compared with the reference period, to control for seasonal variations and aging of the study population. ResultsWe observed a distinct increase in CVD-related deaths in March and April 2020 as compared to the corresponding months of the three preceding years. The observed number of CVD death (n=217) was almost doubled in April, compared with the expected number (n=120), corresponding to an SMR of 1.81 (95% CI 1.58-2.06). We observed a sharp decline of CVD hospitalization in March (n=841) and April (n=454), compared with the expected number (n=1208 for March and 1026 for April), leading to an SIR of 0.70 (95% CI 0.65-0.74) for March and 0.44 (95% CI 0.40-0.48) for April. There was also a clear increase of death, but a clear decrease of hospitalization, in March and April for all the five major subtypes of CVD. ConclusionsWe observed a distinct excess in CVD deaths in the beginning of the COVID-19 outbreak in the UK Biobank population. In addition to CVD complications of SARS-CoV-2 infections, the reduced hospital capacity might have contributed to the observed excess CVD deaths. Key PointsO_ST_ABSQuestionC_ST_ABSHow did the COVID-19 outbreak affect rates of CVD-related death and hospitalization? FindingIn this prospective study involving 421,717 UK Biobank participants, we observed excess CVD-related mortality in parallel with decreased CVD-related hospitalization in the beginning of the COVID-19 pandemic, March and April 2020. MeaningIn addition to severe SARS-CoV-2 infection progressing to CVD-related death, reduced hospital resources might have partially contributed to the excess CVD mortality.
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@#Naturally split Npu DnaE intein can mediate rapid trans-splicing and C-cleavage, which is of great use in many aspects of protein engineering. However, the degradation of NpuC during expression and purification reduces the yield and purity of recombinant protein. N2C, an extended NpuN2-containing N-terminal NpuC fragment, was constructed to improve NpuC stability. N2C was expressed in BL21(DE3) and purified by affinity chromatography. The degradation ratio was calculated by ImageJ, and the factors affecting the C-terminal cleavage reaction of intein, such as temperature, DTT concentration and N/C ratio, were also investigated. The results showed that N2C lowered the proportion of degradation to 2.7%-7.2% and the yield of C-terminal cleavage reached 90% in 30 min at 37 °C with an N/C ratio of 5∶1 catalyzed by 1 mmol/L DTT. N2C can not only improve the stability of NpuC in Escherichia coli expression system, but also retain the activity of C-terminal cleavage reaction, which is of great significance for its application in protein purification.
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@#The purpose of this experiment is to achieve the soluble expression of immunotoxins in Escherichia coli and avoid the complicated operation caused by the formation of inclusion bodies. An anti-mesothelin monoclonal antibody SS1 and it′s derivative SS1P which composing of SS1 and a truncated pseudomonas exotoxin PE38KDEL were used as the passenger protein. We took advantages of solubility promoting fusion tags and the self-cleaving split intein in recombinant antibody fragment and immunotoxin expression and purification. We constructed solubilizing tags-NpuCD118G fusion tags, and recombinant SS1/SS1P were fused at the C-terminal of the fusion tags. The constructs were expressed in E. coli(SHuffle T7)cytoplasm in soluble form at low temperature. Dextrin Beads 6FF column and Nickel column was used to purify the fusion protein. The self-cleavage of the fusion protein was achieved by adding the NpuN fragment. The released solubilizing tag and unreacted precursor were removed by Nickel column and the cleaved antibody fragment and immunotoxinwere further captured by Capto L. The dissociation constant of the obtained Fv and immunotoxin were determined by Fortebio. In summary, the current method could enhance the solubility of antibody fragment and immunotoxin in E. coli, and could improve the purification process. This method provides a reference for the development of a method for soluble expression and purification of immunotoxin-type pharmaceutical recombinant proteins based on the Escherichia coli expression system.
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The 21st century is regarded as the century of biotechnological drugs, among which monoclonal antibodies and their derived targeting drugs have established themselves as the leading modality of biopharmaceutical pharmaceutics for a wide range of indications covering malignant tumors and autoimmune disorders. Since the manufacturing of the first antibody drug from hybridoma cells, the technologies have been intensely studied and there emerged numerous breakthroughs in recombinant cell line establishment, antibody expression and purification, quality control and other related areas. This article summarizes the critical progresses of antibody drugs expression technologies, especially of mammalian cell expression system, Escherichia coli expression system, the transgenic animal reactor and the cell free protein synthesis system, to give a detailed illustration of the recent advances in antibody drugs development.
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Animals , Antibodies, Monoclonal , Biotechnology , Cell Line , Escherichia coli , HybridomasABSTRACT
Objective@#To analyze 18F-fluorodeoxyglucose(FDG) PET/CT imaging manifestations in patients with peritoneal carcinomatosis (PC) from colorectal cancer (CRC) and investigate its clinical significance.@*Methods@#From May 2016 to August 2018, 46 patients (25 males, 21 females; age range: 36-82(62.0±10.4) years) with PC from CRC who underwent 18F-FDG PET/CT imaging in Affiliated Hospital of Nantong University and had complete clinical data were retrospectively analyzed. The peritoneal carcinomatosis index (PCI) grading system was used to evaluate the PC lesions. Independent-sample t test and Kruskal-Wallis H test were used for data analysis.@*Results@#There were various CT manifestations of PC, while FDG metabolism on PET was observed in all 46 patients. Patients were divided into different groups according to the location of the primary CRC lesion. The diameter of PC lesion in the left colon group was (2.46±1.26) cm, which was significantly different from that of the rectum group ((3.19±1.72) cm; t=-2.77, P<0.01). The maximum standardized uptake value (SUVmax) in the right colon group were significantly higher than that in the left colon group (9.16±4.79 vs 6.99±3.50; t=2.92, P<0.01). The PCI score ranged from 1 to 30 in 46 patients, and there was no significant difference in PCI score distribution (≥20 vs <20) among the right colon group, left colon group and rectum group (H=0.242, P>0.05). Ten patients had abdominal and pelvic effusion.@*Conclusion@#18F-FDG PET/CT can well display the PC in patients with CRC, and the combination of PCI and 18F-FDG PET/CT plays an important role in the diagnosis and treatment of PC.
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@#Intein is a functional protein that mediates self-cleavage from precursor protein and simultaneously connects the exteins on both sides of the intein via peptide bonds. Among all kinds of inteins, split intein has a wide range of applications in the field of antibody ligation. However, since the naturally split intein specifically recognizes the first three amino acid sequences “cysteine, phenylalanine, and asparagine”(CFN)of the extein, exogenous amino acids are inevitably introduced after the protein splicing reaction. In this study, the amino acid sequence “cysteine, aspartic acid, and lysine”(CDK)of the antibody hinge region was substituted for “CFN” as the recognition site for the intein and the split intein Npu DnaE was mutated into Npu*GEP DnaE. The results showed that the mutant could recognize “CDK” and the intein splicing reaction could successfully take place. The factors affecting the intein splicing reaction platform, such as pH, temperature and the concentration of NaCl and DTT were investigated in this study. The results showed that the splicing reaction of the mutant performed well, which indicated its potential usefulness in bispecific antibody assembly. In conclusion, the problem of introducing foreign amino acids was alleviated, the broadness of intein substrate was further expanded, and further technical support for the application of intein to the antibody assembly was provided.
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OBJECTIVE@#To analyze the current status of diagnosis and management of acute appendicitis (AA) in China.@*METHODS@#Questionnaire survey was used to retrospectively collect data of hospitalized patients with AA from 43 medical centers nationwide in 2017 (Sort by number of cases provided: Jinling Hospital of Medical School of Nanjing University, The First Affiliated Hospital of Xinjiang Medical University, Lu'an People's Hospital, Tengzhou Central People's Hospital, Dalian Central Hospital, The Affiliated Hospital of Xuzhou Medical University, Dongying People's Hospital, Jinjiang Hospital of Traditional Chinese Medicine, Huangshan Shoukang Hospital, Xuyi People's Hospital, Nanjing Jiangbei People's Hospital, Lanzhou 940th Hospital of PLA, Heze Municipal Hospital, The First College of Clinical Medical Science of China Three Gorges University, Affiliated Jiujiang Hospital of Nanchang University, The Second People's Hospital of Hefei, Affiliated Central Hospital of Shandong Zaozhuang Mining Group, The Third People's Hospital of Kunshan City, Xuzhou First People's Hospital, The 81st Group Army Hospital of PLA, Linyi Central Hospital, The General Hospital of Huainan Eastern Hospital Group, The 908th Hospital of PLA, Liyang People's Hospital, The 901th Hospital of Joint Logistic Support Force, The Third Affiliated Hospital of Chongqing Medical University, The Fourth Hospital of Jilin University, Harbin Acheng District People's Hospital, The First Affiliated Hospital of Zhengzhou University, Nanjing Luhe People's Hospital, Taixing Municipal People's Hospital, Baotou Central Hospital, The Affiliated Hospital of Nantong University, Linyi People's Hospital, The 72st Group Army Hospital of PLA, Zaozhuang Municipal Hospital, People's Hospital of Dayu County, Taixing City Hospital of Traditional Chinese Medicine, Suzhou Municipal Hospital, Beijing Guang'anmen Hospital, Langxi County Hospital of Traditional Chinese Medicine, Nanyang Central Hospital, The Affiliated People's Hospital of Inner Mongolia Medical University).The diagnosis and management of AA were analyzed through unified summary. Different centers collected and summarized their data in 2017 and sent back the questionnaires for summary.@*RESULTS@#A total of 8 766 AA patients were enrolled from 43 medical centers, including 4 711 males (53.7%) with median age of 39 years and 958 (10.9%) patients over 65 years old. Of 8 776 patients, 5 677 cases (64.6%) received one or more imaging examinations, and the other 3 099 (35.4%) did not receive any imaging examination. A total of 1 858 (21.2%) cases received medical treatment, mainly a combination of nitroimidazoles (1 107 cases, 59.8%) doublet regimen, followed by a single-agent regimen of non-nitroimidazoles (451 cases, 24.4%), a nitroimidazole-free doublet regimen (134 cases, 7.2%), a triple regimen of combined nitroimidazoles (116 cases, 6.3%), nitroimidazole alone (39 cases, 2.1%) and nitroimidazole-free triple regimen (3 cases, 0.2%). Of the 6 908 patients (78.8%) who underwent surgery, 4 319 (62.5%) underwent laparoscopic appendectomy and 2589 (37.5%) underwent open surgery. Ratio of laparotomy was higher in those patients under 16 years old (392 cases) or over 65 years old (258 cases) [15.1%(392/2 589) and 10.0%(258/2 589), respectively, compared with 8.5%(367/4 316) and 8.0%(347/4 316) in the same age group for laparoscopic surgery, χ²=91.415, P<0.001; χ²=15.915,P<0.001]. Patients with complicated appendicitis had higher ratio of undergoing open surgery as compared to those undergoing laparoscopic surgery [26.7%(692/2 589) vs. 15.6%(672/4 316), χ²=125.726, P<0.001].The cure rates of laparoscopic and open surgery were 100.0% and 99.8%(2 585/2 589) respectively without significant difference (P=0.206). Postoperative complication rates were 4.5%(121/2 589) and 4.7%(196/4 316) respectively, and the difference was not statistically significant (χ²=0.065, P=0.799). The incidence of surgical site infection was lower (0.6% vs. 1.7%, χ²=17.315, P<0.001), and hospital stay was shorter [6(4-7) days vs. 6(5-8) days, U=4 384 348.0, P<0.001] in the laparoscopic surgery group, while hospitalization cost was higher (median 12 527 yuan vs. 9 342 yuan, U=2 586 809.0, P<0.001).@*CONCLUSIONS@#The diagnosis of acute appendicitis is still clinically based, supplemented by imaging examination. Appendectomy is still the most effective treatment at present. Laparoscopic appendectomy has become the main treatment strategy, but anti-infective drugs are also very effective.
Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Acute Disease , Anti-Bacterial Agents , Therapeutic Uses , Appendectomy , Appendicitis , Diagnosis , Therapeutics , China , Health Care Surveys , Laparoscopy , Retrospective Studies , Treatment OutcomeABSTRACT
Objective To explore the effectiveness of endoscopic ultrasound( EUS)-guided holmium laser ablation for primary pancreatic implantation tumor in nude mice. Methods Pancreatic cancer cell line SW1990 were implanted into 204-6-week-old male balb/c nude mice to establish primary pancreatic implantation tumor in situ models. Then the nude mice were randomly divided into two groups, the treatment group(n=10) and the control group(n=10). The treatment group underwent EUS-guided holmium laser ablation in the pancreatic tumor. And no interventions were given to the control group. The volume of tumors of the two groups were measured under EUS at time points of 7 d, 14 d and 28 d after ablation. The activities, appetites and psychosis of all nude mice were evaluated in the meantime. At 28 d after ablation, lesions of pancreas were dissected and sliced for H&E staining. Results There were no complications in the treatment group, and all nude mice could tolerate the procedure. The mental state, activities and appetites of nude mice in the experimental group were better than those in the control group. Tumors of the control group enlarged. There was significant difference in the tumor size between the two groups at 28 d after ablation. HE staining showed coagulation necrosis in the ablation area. Conclusion EUS-guided holmium laser, producing coagulative necrosis in the ablation area, is effective for primary pancreatic implantation carcinoma in nude mice for about 28 days.
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Objective To investigate the early predictive value of several commonly used biochemical markers for predicting persistent organ failure ( POF ) in patients with hyperlipidemic acute pancreatitis ( HLAP) . Methods Clinical data of 157 patients with HLAP within 72 hours after the onset of first attack who were admitted to the Dept. of Gastroenterology in Changhai Hospital from January 2015 to December 2017 were retrospectively analyzed, including 106 cases without POF ( non POF group ) and 51 cases with POF ( POF group) . Hct, BUN, Cr, APACHEⅡand BISAP were recorded within 24 hours after admission. Receiver-operating characteristic ( ROC) curve was drawn to calculate area under the ROC curve ( AUC) and evaluate the performance of Hct, BUN, Cr, APACHEⅡand BISAP scores in predicting HLAP complicated with POF, which was compared by DeLong test. Results Values of BUN, Cr, APACHEⅡand BISAP were significantly higher in HLAP patients with POF than those without POF [(10. 30 ± 7. 43) vs (5. 34 ± 2. 26) mmol/L, (165. 31 ± 123. 93) vs (65. 61 ± 20. 82)μmol/L, (10. 22 ± 6. 22) vs (4. 61 ± 2. 99) points, (2. 61 ± 0. 87) vs (1. 42 ± 1.07) points], and the differences were all statistically significant (all P<0.05), whereas Hct was not significantly different between the two groups. The AUC of Cr and BUN for predicting POF was 0. 77(95％ CI, 0. 69-0. 86) and 0. 71 (95％ CI, 0. 61-0. 81), respectively, and the optimum predictive Cut-off values were 130 μmol/L and 8. 95 mmol/L, respectively. The sensitivity was 53％, and the specificity was 99％ and 94％;the accuracy was 84％ and 81％;negative predictive value was 81％, and positive predictive value was 96％ and 82％. DeLong test showed that predictive performance of BUN and Cr was not statistically different from that of APACHEⅡand BISAP. Conclusions Cr≥130 μmol/L and BUN≥8. 95 mmol/L can be used clinically to predict the presence of POF in HLAP, and the predictive efficacy were comparable to APACHEⅡand BISAP.
