Endotoxins are common exogenous pyrogens. Excessive endotoxins in medical devices and injections can lead to serious consequences such as sepsis, septic shock, and even death. Therefore, endotoxin detection plays a crucial role in medical, pharmaceutical, and food sectors. The wide application of Limulus amebocyte lysate (LAL) has led to a sharp decline in the number of horseshoe crabs. Moreover, the LAL assay has limitations such as interbatch variations and difficulty in quantification. The recombinant factor C (rFC) assay is stable between batches, highly sensitive, and capable of quantitation, and thus it can be used as an alternative for the LAL assay. However, the high cost and complex procedures involved in producing recombinant factor C have limited the widespread application of this method. In order to simplify the preparation and reduce the production cost of recombinant factor C, this study focuses on the production of recombinant factor C based on the baculovirus expression system. Multiple measures such as a high-yield and anti-apoptotic vector qBac-IIIG, the optimal signal peptide, and the optimized codon were used to reach the goal of endotoxin detection with cell supernatant. This method simplifies the steps of protein purification. The sensitivity of the supernatant reached 0.05 EU/mL in a 1-L fermentation system, and 500 000 detecting reactions can be supported per liter of fermentation broth. This study increases the yield and activity of recombinant factor C, simplifies the procedures of protein purification, and reduces the cost, laying a foundation for the promotion and application of recombinant factor C in endotoxin detection.
Animals ; Recombinant Proteins/genetics* ; Horseshoe Crabs/chemistry* ; Baculoviridae/metabolism* ; Endotoxins/analysis* ; Protein C/biosynthesis* ; Genetic Vectors/genetics* ; Arthropod Proteins/genetics* ; Enzyme Precursors ; Serine Endopeptidases

177Lu-prostate specific membrane antigen(PSMA)radio-ligand therapy has been approved abroad for advanced prostate cancer and has been in several clinical trials in China.Based on domestic clinical practice and experimental data and referred to international experience and viewpoints,the expert group forms a consensus on the clinical application of 177Lu-PSMA radio-ligand therapy in prostate cancer to guide clinical practice.

Ischemic stroke(IS)is the main cause of neurological dysfunction in adults in China,and rapid,timely,and accurate prediction of post-stroke outcome and intervention treatment are crucial.Currently,the prognosis of ischemic stroke mainly relies on neuroimaging and clinical assessment,and there is still a lack of objective and simple rapid prediction tools.Recent studies have shown that early measurement of peripheral blood-derived biomarkers may be able to predict stroke patient outcomes,thereby optimizing stroke management,improving patient rehabilitation,and improving stroke outcomes.This article reviews the progress of studies on the correlation between peripheral blood biomarkers and clinical prognosis of ischemic stroke.

Abstract: Objective　To analyze the emergency response and long-term intervention effects after the detection of infectious snails epidemic by loop-mediated isothermal amplification (LAMP) assays in Hannan District, Wuhan City, and to explore the application of LAMP in early surveillance and early-warning of schistosomiasis transmission. Methods Snails picked up by the risk monitoring system in Hannan District were examined by anatomical microscopy and LAMP technology to identify the schistosomiasis infection. Emergency response and intensive intervention were initiated in the environment where positive snails appeared, and the long-term effects were evaluated. Results In May 2018, the infectious snails were detected by LAMP technology in Hannan District, and the positive snails were located in Zhujiacha, Dongzhuang Village, Obstacles and weeds were removed and buried by machine in Zhujiacha. 12 700 m2 of snails were killed by drugs, and the mortality rate of snails was more than 80%; no new seropositive persons were found in the emergency examination within 500 m of the positive snail sites. 506 people were examined in Dong Zhuang Village at the end of the year, and 30 positive IHA cases were detected with a blood positive rate of 5.93%, no positive fecal test was found, and all positive blood test patients took preventive medication. The monitoring results of sentinel rats and wild feces were all negative. Health education was carried out, 7 warning signs were deployed and refreshed, and 500 publicity brochures were distributed. After nearly three years of intensified intervention and monitoring in the villages where the positive environment is located, and the density of snails on the stubborn snail has dropped from 0.094/frame to 0.027/frame, and the positive rate of blood test in Dongzhuang Village has steadily dropped from 5.93% to 3.74%. Conclusions The infected snails missed by microscopy were detected by LAMP in Hannan District, which created conditions for the rapid emergency treatment of environment and elimination of positive snail and improved the sensitivity of the surveillance and early warning system in transmission-interrupted areas.

BACKGROUND: Long-term remote ischemic conditioning (RIC) has been proven to be beneficial in multiple diseases, such as cerebral and cardiovascular diseases. However, the hyperacute and acute effects of a single RIC stimulus are still not clear. Quantitative proteomic analyses of plasma proteins following RIC application have been conducted in preclinical and clinical studies but exhibit high heterogeneity in results due to wide variations in experimental setups and sampling procedures. Hence, this study aimed to explore the immediate effects of RIC on plasma proteome in healthy young adults to exclude confounding factors of disease entity, such as medications and gender. METHODS: Young healthy male participants were enrolled after a systematic physical examination and 6-month lifestyle observation. Individual RIC sessions included five cycles of alternative ischemia and reperfusion, each lasting for 5 min in bilateral forearms. Blood samples were collected at baseline, 5 min after RIC, and 2 h after RIC, and then samples were processed for proteomic analysis using liquid chromatography-tandem mass spectrometry method. RESULTS: Proteins related to lipid metabolism (e.g., Apolipoprotein F), coagulation factors (hepatocyte growth factor activator preproprotein), members of complement cascades (mannan-binding lectin serine protease 1 isoform 2 precursor), and inflammatory responses (carboxypeptidase N catalytic chain precursor) were differentially altered at their serum levels following the RIC intervention. The most enriched pathways were protein glycosylation and complement/coagulation cascades. CONCLUSIONS One-time RIC stimulus may induce instant cellular responses like anti-inflammation, coagulation, and fibrinolysis balancing, and lipid metabolism regulation which are protective in different perspectives. Protective effects of single RIC in hyperacute and acute phases may be exploited in clinical emergency settings due to apparently beneficial alterations in plasma proteome profile. Furthermore, the beneficial effects of long-term (repeated) RIC interventions in preventing chronic cardiovascular diseases among general populations can also be expected based on our study findings.
Young Adult ; Humans ; Male ; Proteome ; Cardiovascular Diseases ; Proteomics ; Ischemia ; Blood Coagulation

Humans ; Rectum/surgery* ; Liposarcoma/surgery* ; Biomarkers, Tumor

The oral cavity is the second largest microbial bank in humans after the intestinal canal, colonizing a large number of microorganisms including viruses, bacteria, archaea, fungi and protozoa. The great number of microbial cells, good DNA stability, and individual has a unique microbial community, these characteristics make the human microbiome expected to become a new biomarker for forensic individual identification. This article describes the characteristics of human oral microorganisms and microbial molecular markers in detail, analyzes the potential application value of microorganisms in forensic individual identification, and reviews the research progress of human oral microorganisms in forensic individual identification.
Humans ; Microbiota ; Forensic Medicine

Objective: To analyze the course of disease and epidemiological parameters of COVID-19 and provide evidence for making prevention and control strategies. Methods: To display the distribution of course of disease of the infectors who had close contacts with COVID-19 cases from January 1 to March 15, 2020 in Guangdong Provincial, the models of Lognormal, Weibull and gamma distribution were applied. A descriptive analysis was conducted on the basic characteristics and epidemiological parameters of course of disease. Results: In total, 515 of 11 580 close contacts were infected, with an attack rate about 4.4%, including 449 confirmed cases and 66 asymptomatic cases. Lognormal distribution was fitting best for latent period, incubation period, pre-symptomatic infection period of confirmed cases and infection period of asymptomatic cases; Gamma distribution was fitting best for infectious period and clinical symptom period of confirmed cases; Weibull distribution was fitting best for latent period of asymptomatic cases. The latent period, incubation period, pre-symptomatic infection period, infectious period and clinical symptoms period of confirmed cases were 4.50 (95%CI:3.86-5.13) days, 5.12 (95%CI:4.63-5.62) days, 0.87 (95%CI:0.67-1.07) days, 11.89 (95%CI:9.81-13.98) days and 22.00 (95%CI:21.24-22.77) days, respectively. The latent period and infectious period of asymptomatic cases were 8.88 (95%CI:6.89-10.86) days and 6.18 (95%CI:1.89-10.47) days, respectively. Conclusion: The estimated course of COVID-19 and related epidemiological parameters are similar to the existing data.
COVID-19 ; Cohort Studies ; Contact Tracing ; Humans ; Incidence ; Prospective Studies

Objective:To compare the inhibitory effect of human CD55(hCD55)expressed on porcine peripheral blood mononuclear cells(PBMC)on rabbit complement-and human complement-dependent cytotoxicity(CDC).Methods:Three α1, 3-galactosyltransferase gene knockout(GTKO)pigs from the same strain were selected.Two were transferred with hCD55 gene.According to the expression level of hCD55, the animals were divided into three groups of GTKO, GTKO/hCD55 Low(low-expression of hCD55)and GTKO/hCD55 High(high-expression of hCD55). After PBMC from these pigs were incubated with complement-inactivated pooled human serum(20 cases), rabbit complement-or human complement-dependent cytotoxicity and binding of antibodies(IgM/G)to pig PBMC were detected by flow cytometry. Results:No significant difference existed in binding of human serum xenoreactive antibodies to PBMC from three groups.The cytotoxicity to GTKO pig PBMC mediated by rabbit complement or human complement were 98.97%±0.50% and 82.73%±3.20% respectively.Both values were quite high.Compared with GTKO group, a low expression of hCD55 had no significant inhibitory effect on rabbit complement-dependent cytotoxicity(97.07%±2.25% vs. 98.9%±0.50%, P=0.2 267) while a high expression of hCD55 exerted a mild inhibitory effect on rabbit complement-dependent cytotoxicity(81.70%±5.86% vs. 98.9%±0.50%, P=0.0 355). Differently, a low expression of hCD55 had a potent inhibitory effect on human complement-dependent cytotoxicity(23.83%±3.53% vs. 82.73%±3.20%, P<0.0 001). Compared with hCD55 low-expression group, a high expression of hCD55 had a further inhibitory effect on human complement-dependent cytotoxicity(2.79%±0.45% vs. 82.73%±3.20%, P=0.009), attaining the level of negative control group.The inhibitory effect of low/high expression of hCD55 on human complement-mediated CDC was significantly better than that on rabbit complement-mediated CDC. Conclusions:Compared with traditional CDC counterpart using rabbit complement, modified CDC technology of commercial standard human complement is recommended for evaluating the regulatory effect of hCD55 expressed on cell surface from GTKO/hCD55 genetically engineered pigs.It thus provides experimental rationales for establishing a novel CDC experimental system of effectively evaluate the function of hCD55 after xenotransplantation.

Objective:To investigate the value of plasma Epstein-Barr virus (EBV) DNA detection in the screening of nasopharyngeal carcinoma (NPC) and its clinical application in non-high-risk areas.Methods:Plasma EBV DNA results in 1 153 newly diagnosed nasopharyngeal carcinoma patients who were treated in Sichuan Cancer Hospital from 2015 to 2020 and 244 healthy control cases with matched sex and age were retrospectively analyzed. EBV DNA were detected by quantitative real-time PCR. Positive rate of EBV DNA was determined by the cutoff value of 400 (≥400 copies/ml as positive) and optimization threshold method (presence of S amplification curve as positive). Further analyses were conducted to compare EBV DNA load in different clinical stage, TNM stage and regions distribution characteristics. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic value of the cutoff value of 400 and optimization threshold method for NPC.Results:Compared with healthy controls, EBV DNA increased significantly in newly diagnosed NPC patients ( P<0.001). Both evaluation methods revealed that the EBV DNA positive percentage increased with TNM and clinical stage ( P<0.001). With 400 copies/ml as cutoff value, the diagnostic sensitivity and specificity were 40.85% and 100%, respectively. The area under the curve was 0.704 (95% CI 0.676-0.733, P<0.001). Evaluated by the optimization threshold method, the sensitivity and specificity could improve to 82.0% and 99.2%, respectively, and the area under the curve reached 0.910 (95% CI 0.894-0.924, P<0.001). Conclusions:In the low prevalence area of nasopharyngeal carcinoma, the sensitivity for diagnosis of nasopharyngeal carcinoma is only 40.9% by the 400 copies/ml cutoff value method. The optimization threshold method is a better choice to improve the diagnostic sensitivity without lowering the diagnostic specificity.