Objective:To construct a sizeable naive human Fab phage display antibody library to screen high-affinity specific antibodies in vitro. Methods:Total RNA was extracted from peripheral blood mononuclear cells (PBMCs) of 126 healthy individuals, subsequently reverse-transcribed into cDNA, and used as a template. PCR amplification was performed to obtain the V H from IgG, IgM and light chain κ, λ, separately, with the initial PCR products serving as templates for a second round of PCR. Overlap extension PCR was employed to generate fragments of the κ and λ light chains. These fragments were ligated with the phage vector pNC3, which harbors the variable region 1 of the heavy chain, to construct a recombinant phage plasmid. This plasmid was then electroporated into competent Escherichia Coli TG1 cells to establish a naive human Fab phage display antibody library. One hundred clones were randomly selected for identification and sequencing, and antibody gene polymorphisms were analyzed using the IMGT database and MAFFT software. Recombinant α-hemolysin from Staphylococcus aureus was utilized to screen Fab antibody fragments through biopanning of the antibody library, followed by random selection of phage ELISA-identified clones. The positive clones (antigen A450∶blank control A450≥2.1) were sequenced. Results:Two large naive Fab phage display antibody libraries were successfully constructed, in which the capacity of κ and λ chain antibody libraries were 1.25×10 11 and 1.54×10 11, respectively. The titers for two antibody libraries were 6.04×10 13 CFU/ml and 3.50×10 13 CFU/ml. The positive transformation insertion rates for κ and λ chain antibody libraries were 96% (96/100) and 100% (100/100), respectively. Sequence analysis revealed that all antibody sequences were unique. The amino acid sequences in the skeletal region were relatively conserved. In contrast, significant variations in the length of the complementarity determining region (CDR) were found, and the diversity of amino acid sequence of the complementary determining region was high, especially the CDR3. Analysis using the IMGT database indicated that the sequences exhibited a broad distribution across variable-diversity-joining gene families. After six rounds of panning, specific phage antibodies enrichment targeting α-hemolysin were achieved. A total of 142 monoclonal antibodies were sequenced, yielding 8 distinct Fab antibody sequences. Conclusion:This study successfully constructed two naive human Fab phage display antibody libraries with large capacity and good diversity, which can be used for screening human antibodies for serum epidemiology.

Objectives:This study aims to evaluate the causal relationship between plasma proteins and myocardial infarction(MI)using two-sample bidirectional Mendelian randomization(MR)analysis,identify key biomarkers,and validate their expression.Methods:The study utilized publicly available genome-wide association study(GWAS)data of 4 907 plasma proteins as the exposure factor,with single nucleotide polymorphisms(SNPs)as instrumental variables,and four MI datasets as outcomes.Two-sample MR analysis was performed using the inverse variance weighted(IVW)method,complemented by simple model,weighted model,weighted median estimator(WME),and MR-Egger regression methods to assess the causal relationship between exposure factors and outcomes.Venn diagrams and word clouds were used to screen proteins associated with MI as candidate biomarkers.Reverse MR analysis was conducted to evaluate reverse causality.Sensitivity analysis was performed to assess the robustness of the results.Immunohistochemistry(IHC)was used to validate the expression of proteasome activator subunit 1(PSME1)and vacuolar protein sorting 29(VPS29)in the aorta of mice,and enzyme-linked immunosorbent assay(ELISA)was used to verify the expression of PSME1 and VPS29 in plasma from patients with acute myocardial infarction(AMI).Results:The two-sample MR analysis indicated that PSME1 was significantly negatively associated with myocardial infarction in all four datasets,with OR(95%CI)of 0.684(0.557-0.839),0.990(0.987-0.993),0.579(0.448-0.748),and 0.993(0.990-0.996),respectively,with all P<0.001.Similarly,VPS29 also showed a significant negative association with MI in all four datasets,with OR(95%CI)of 0.902(0.862-0.945),0.998(0.997-0.999),0.866(0.808-0.929),and 0.998(0.997-0.999),respectively,with all P<0.001.Reverse MR analysis did not detect reverse causality,and sensitivity analysis confirmed the robustness of the results.IHC results showed significantly reduced expression of PSME1 and VPS29 in the aortas of AMI mice with an atherosclerotic background compared to control mice(both P<0.05).ELISA results indicated significantly lower plasma levels of PSME1 and VPS29 in AMI patients compared to healthy controls(both P<0.05).Conclusions:Higher levels of PSME1 and VPS29 are negatively associated with the risk of MI,suggesting that PSME1 and VPS29 may serve as protective biomarkers for cardiovascular diseases.

Objective:To construct a sizeable naive human Fab phage display antibody library to screen high-affinity specific antibodies in vitro. Methods:Total RNA was extracted from peripheral blood mononuclear cells (PBMCs) of 126 healthy individuals, subsequently reverse-transcribed into cDNA, and used as a template. PCR amplification was performed to obtain the V H from IgG, IgM and light chain κ, λ, separately, with the initial PCR products serving as templates for a second round of PCR. Overlap extension PCR was employed to generate fragments of the κ and λ light chains. These fragments were ligated with the phage vector pNC3, which harbors the variable region 1 of the heavy chain, to construct a recombinant phage plasmid. This plasmid was then electroporated into competent Escherichia Coli TG1 cells to establish a naive human Fab phage display antibody library. One hundred clones were randomly selected for identification and sequencing, and antibody gene polymorphisms were analyzed using the IMGT database and MAFFT software. Recombinant α-hemolysin from Staphylococcus aureus was utilized to screen Fab antibody fragments through biopanning of the antibody library, followed by random selection of phage ELISA-identified clones. The positive clones (antigen A450∶blank control A450≥2.1) were sequenced. Results:Two large naive Fab phage display antibody libraries were successfully constructed, in which the capacity of κ and λ chain antibody libraries were 1.25×10 11 and 1.54×10 11, respectively. The titers for two antibody libraries were 6.04×10 13 CFU/ml and 3.50×10 13 CFU/ml. The positive transformation insertion rates for κ and λ chain antibody libraries were 96% (96/100) and 100% (100/100), respectively. Sequence analysis revealed that all antibody sequences were unique. The amino acid sequences in the skeletal region were relatively conserved. In contrast, significant variations in the length of the complementarity determining region (CDR) were found, and the diversity of amino acid sequence of the complementary determining region was high, especially the CDR3. Analysis using the IMGT database indicated that the sequences exhibited a broad distribution across variable-diversity-joining gene families. After six rounds of panning, specific phage antibodies enrichment targeting α-hemolysin were achieved. A total of 142 monoclonal antibodies were sequenced, yielding 8 distinct Fab antibody sequences. Conclusion:This study successfully constructed two naive human Fab phage display antibody libraries with large capacity and good diversity, which can be used for screening human antibodies for serum epidemiology.

Objectives:This study aims to evaluate the causal relationship between plasma proteins and myocardial infarction(MI)using two-sample bidirectional Mendelian randomization(MR)analysis,identify key biomarkers,and validate their expression.Methods:The study utilized publicly available genome-wide association study(GWAS)data of 4 907 plasma proteins as the exposure factor,with single nucleotide polymorphisms(SNPs)as instrumental variables,and four MI datasets as outcomes.Two-sample MR analysis was performed using the inverse variance weighted(IVW)method,complemented by simple model,weighted model,weighted median estimator(WME),and MR-Egger regression methods to assess the causal relationship between exposure factors and outcomes.Venn diagrams and word clouds were used to screen proteins associated with MI as candidate biomarkers.Reverse MR analysis was conducted to evaluate reverse causality.Sensitivity analysis was performed to assess the robustness of the results.Immunohistochemistry(IHC)was used to validate the expression of proteasome activator subunit 1(PSME1)and vacuolar protein sorting 29(VPS29)in the aorta of mice,and enzyme-linked immunosorbent assay(ELISA)was used to verify the expression of PSME1 and VPS29 in plasma from patients with acute myocardial infarction(AMI).Results:The two-sample MR analysis indicated that PSME1 was significantly negatively associated with myocardial infarction in all four datasets,with OR(95%CI)of 0.684(0.557-0.839),0.990(0.987-0.993),0.579(0.448-0.748),and 0.993(0.990-0.996),respectively,with all P<0.001.Similarly,VPS29 also showed a significant negative association with MI in all four datasets,with OR(95%CI)of 0.902(0.862-0.945),0.998(0.997-0.999),0.866(0.808-0.929),and 0.998(0.997-0.999),respectively,with all P<0.001.Reverse MR analysis did not detect reverse causality,and sensitivity analysis confirmed the robustness of the results.IHC results showed significantly reduced expression of PSME1 and VPS29 in the aortas of AMI mice with an atherosclerotic background compared to control mice(both P<0.05).ELISA results indicated significantly lower plasma levels of PSME1 and VPS29 in AMI patients compared to healthy controls(both P<0.05).Conclusions:Higher levels of PSME1 and VPS29 are negatively associated with the risk of MI,suggesting that PSME1 and VPS29 may serve as protective biomarkers for cardiovascular diseases.

OBJECTIVE: To explore the genetic etiology of a child with D bifunctional protein deficiency (DBPD) born to a consanguineous pedigree. METHODS: A child with DBPD who was admitted to the First Affiliated Hospital of Hainan Medical College on January 6, 2022 due to hypotonia and global developmental delay was selected as the study subject. Clinical data of her pedigree members were collected. Peripheral blood samples of the child, her parents and elder sisters were collected and subjected to whole exome sequencing. Candidate variant was validated by Sanger sequencing and bioinformatic analysis. RESULTS: The child, a 2-year-and-9-month-old female, had featured hypotonia, growth retardation, unstable head lift, and sensorineural deafness. Serum long-chain fatty acids were elevated, and auditory brainstem evoked potentials had failed to elicit V waves in both ears with 90 dBnHL stimulation. Brain MRI revealed thinning of corpus callosum and white matter hypoplasia. The child's parents were secondary cousins. Their elder daughter had a normal phenotype and no clinical symptoms related to DBPD. Elder son had frequent convulsions, hypotonia and feeding difficulties after birth, and had died one and a half month later. Genetic testing revealed that the child had harbored homozygous c.483G>T (p.Gln161His) variants of the HSD17B4 gene, for which both of her parents and elder sisters were carriers. Based on the guidelines from the American College of Medical Genetics and Genomics, the c.483G>T (p.Gln161His) was rated as a pathogenic variant (PM1+PM2_Supporting+PP1+PP3+PP4). CONCLUSION The homozygous c.483G>T (p.Gln161His) variants of the HSD17B4 gene caused by the consanguineous marriage probably underlay the DBPD in this child.
Female ; Humans ; Pedigree ; Muscle Hypotonia ; Hearing Loss, Sensorineural ; Protein Deficiency ; Mutation

As one of the hallmarks of cancer, metabolic reprogramming leads to cancer progression, and targeting glycolytic enzymes could be useful strategies for cancer therapy. By screening a small molecule library consisting of 1320 FDA-approved drugs, we found that penfluridol, an antipsychotic drug used to treat schizophrenia, could inhibit glycolysis and induce apoptosis in esophageal squamous cell carcinoma (ESCC). Gene profiling and Ingenuity Pathway Analysis suggested the important role of AMPK in action mechanism of penfluridol. By using drug affinity responsive target stability (DARTS) technology and proteomics, we identified phosphofructokinase, liver type (PFKL), a key enzyme in glycolysis, as a direct target of penfluridol. Penfluridol could not exhibit its anticancer property in PFKL-deficient cancer cells, illustrating that PFKL is essential for the bioactivity of penfluridol. High PFKL expression is correlated with advanced stages and poor survival of ESCC patients, and silencing of PFKL significantly suppressed tumor growth. Mechanistically, direct binding of penfluridol and PFKL inhibits glucose consumption, lactate and ATP production, leads to nuclear translocation of FOXO3a and subsequent transcriptional activation of BIM in an AMPK-dependent manner. Taken together, PFKL is a potential prognostic biomarker and therapeutic target in ESCC, and penfluridol may be a new therapeutic option for management of this lethal disease.

Background::Whether anesthetic depth affects postoperative outcomes remains controversial. This meta-analysis aimed to evaluate the effects of deep vs. light anesthesia on postoperative pain, cognitive function, recovery from anesthesia, complications, and mortality. Methods::PubMed, EMBASE, and Cochrane CENTRAL databases were searched until January 2022 for randomized controlled trials comparing deep and light anesthesia in adult surgical patients. The co-primary outcomes were postoperative pain and delirium (assessed using the confusion assessment method). We conducted a meta-analysis using a random-effects model. We assessed publication bias using the Begg’s rank correlation test and Egger’s linear regression. We evaluated the evidence using the trial sequential analysis and Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. We conducted subgroup analyses for pain scores at different postoperative time points and delirium according to cardiac or non-cardiac surgery.Results::A total of 26 trials with 10,743 patients were included. Deep anesthesia compared with light anesthesia (a mean difference in bispectral index of -12 to -11) was associated with lower pain scores at rest at 0 to 1 h postoperatively (weighted mean difference = -0.72, 95% confidence interval [CI] = -1.25 to -0.18, P= 0.009; moderate-quality evidence) and an increased incidence of postoperative delirium (24.95% vs. 15.92%; risk ratio = 1.57, 95% CI = 1.28-1.91, P < 0.0001; high-quality evidence). No publication bias was detected. For the exploratory secondary outcomes, deep anesthesia was associated with prolonged postoperative recovery, without affecting neurocognitive outcomes, major complications, or mortality. In the subgroup analyses, the deep anesthesia group had lower pain scores at rest and on movement during 24 h postoperatively, without statistically significant subgroup differences, and deep anesthesia was associated with an increased incidence of delirium after non-cardiac and cardiac surgeries, without statistically significant subgroup differences. Conclusions::Deep anesthesia reduced early postoperative pain but increased postoperative delirium. The current evidence does not support the use of deep anesthesia in clinical practice.

Objective:To explore the implementation of individualized lung protection ventilation strategy in pediatric acute respiratory distress syndrome(pARDS)guided by transthoracic electrical impedance tomography(EIT)and critical care ultrasound(CCU).Methods:We retrospectively analyzed the therapeutic process of protective ventilation strategy in one case of severe pARDS.EIT and CCU were used to guide the implementation of lung protective ventilation strategy.Results:EIT was used to guide lung recruitment and optimal positive end-expiratory pressure titration.CCU was used to assess hemodynamics and lung status of ARDS patient, and guide the implementation of right ventricular protective ventilation and circulatory protective ventilation.Finally, the patient eventually survived.Conclusion:The idea of ARDS protective ventilation has changed from traditional lung protective ventilation to right heart protective ventilation and circulatory protective ventilation, and finally achieved the protection of pulmonary vascular endothelium.EIT and CCU enrich the understanding of the pathophysiology and protective ventilation strategy in pARDS.

Objective:To study the respiratory morbidity and the risk factors of respiratory complications in late-preterm infants.Methods:The data of 959 late-preterm infants in 21 hospitals in Beijing from October 2015 to April 2016 were collected.These infants were divided into the respiratory morbidity group (237 cases) and the control group (722 cases) according to whether they had short-term respiratory morbidity after birth.Clinical data of the two groups were compared.Results:Among the 959 late-preterm babies, 530 were male and 429 were female.Two hundred and thirty-seven cases (24.7%) developed short-term respiratory morbidity after birth.Infectious pneumonia developed in the most cases (81 cases, 8.4%), followed by transient tachypnea (65 cases, 6.8%), amniotic fluid aspiration (51 cases, 5.3%), and respiratory distress syndrome (24 cases, 2.5%) successively.All the infants recovered and discharged.There were no differences between gender and maternal age between 2 groups (all P>0.05). Compared with the control group, more late-preterm infants were delivered by cesarean section (73.4% vs.59.7%, χ2=14.43, P<0.001) and the 1-minute Apgar score was lower [(9.41±1.66) scores vs.(9.83±0.53) scores, t=5.40, P<0.001] in the respiratory morbidity group.The differences were statistically significant.There were more cases with maternal complications in the respiratory morbidity group that in the control group (66.7% vs.58.6%, χ2=4.877, P=0.027), but no difference in various complications between 2 groups was observed ( P>0.05). In the respiratory morbidity group, the most frequent complications were maternal hypertension and preeclampsia (27.8% vs.22.6%, χ2=2.728, P=0.099). There were no differences between 2 groups in gestational age, birth weight and birth length (all P>0.05). There were more infants small for gestational age and large for gestational age in the respiratory morbidity group than in the control group (18.8% vs.14.1%, 6.3% vs.2.4%, χ2=8.960, P=0.011). The duration of hospitalization of the respiratory morbidity group was significantly longer than that of the control group [(9.00±4.42) d vs.(6.82±4.19) d, t=6.676, P<0.001] since the infants with respiratory morbidity needed to be hospita-lized. Conclusions:Respiratory diseases occur in about 1/4 of late-preterm infants.Infants who are delivered by cesarean section and whose mothers are complicated with the maternal hypertension and preeclampsia should be monitored closely.Respiratory support should be provided for infants not appropriate for gestational age who are more likely to suffer from respiratory diseases, so that they can successfully pass through the transition period.

Objective:To design a checklist for interhospital transfer of patients undergoing extracorporeal membrane oxygenation (ECMO) therapy and apply it in clinical practice to ensure the transfer safety of patients.Methods:Using convenience sampling, 27 cases of critically ill patients who were transported by the ECMO team of the Department of Critical Care Medicine of Henan Provincial People's Hospital from September 2017 to November 2018 were selected as the control group, and the ECMO interhospital transport was implemented from December 2018 to February 2020, 14 cases of critically ill patients were set as the experimental group.The checklist for interhospital transfer of patients undergoing ECMO therapy was compiled based on relevant literature and guidelines, and applied to critically ill patients who were transported between hospitals under the support of ECMO. The incidence of adverse events between two groups was compared.Results:The incidence of adverse events decreased after the application of the checklist, the difference was not statistically significant (χ 2=3.516, P=0.061) . Conclusions:The use of the ECMO interhospital transfer checklist can effectively standardize the transfer process, improve work efficiency and quality, may reduce transfer risks, and ensure patients' safety.