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

Foot-and-mouth disease (FMD) is one of the major animal infectious diseases in the world. All cloven-hoofed animals are susceptible to FMD. Vaccination is still the first choice for the prevention and control of FMD. mRNA vaccines can be rapidly designed, synthesized, and produced on a large scale in vitro, and they can induce effective protective immune responses, demonstrating the advantages of rapid development, easy preparation, and low biosafety risks. The design of untranslated regions is a key to enhancing the expression and efficacy of mRNA vaccines. In order to generate an efficient FMD mRNA vaccine, we designed three FMD P12A3C expression vectors with different untranslated regions and synthesized corresponding mRNAs. By comparing expression efficiency of these vectors and their mRNAs at different time points and in different cell lines, we found that the mRNA P12A3C-UTR3 had the best expression and universality. This study laid a foundation for the development of mRNA vaccines against FMD and provided a theoretical basis for the optimal sequence design of efficient mRNA.
Foot-and-Mouth Disease Virus/genetics* ; Animals ; RNA, Messenger/biosynthesis* ; Foot-and-Mouth Disease/immunology* ; Antigens, Viral/biosynthesis* ; Viral Vaccines/biosynthesis* ; Genetic Vectors/genetics* ; Cell Line ; Vaccines, DNA/immunology*

OBJECTIVES: To study the effect of breastfeeding on immune function in infants with human cytomegalovirus (HCMV) infection. METHODS: A retrospective analysis was performed on the medical data of 135 infants with HCMV infection who were admitted to Children's Hospital Affiliated to Zhengzhou University from January 2021 to May 2022, and all these infants received breastfeeding. According to the results of breast milk HCMV-DNA testing, the infants were divided into two groups: breast milk HCMV positive (n=78) and breast milk HCMV negative (n=57). According to the median breast milk HCMV-DNA load, the infants in the breast milk HCMV positive group were further divided into two subgroups: high viral load and low viral load (n=39 each). Related indicators were compared between the breast milk positive and negative HCMV groups and between the breast milk high viral load and low viral load subgroups, including the percentages of peripheral blood lymphocyte subsets (CD3⁺ T cells, CD3⁺CD4⁺ T cells, CD3⁺CD8⁺ T cells, and CD19⁺ B cells), CD4⁺/CD8⁺ ratio, IgG, IgM, IgA, and urine HCMV-DNA load. RESULTS: There were no significant differences in the percentages of CD3⁺ T cells, CD3⁺CD4⁺ T cells, CD3⁺CD8⁺ T cells, and CD19⁺ B cells, CD4⁺/CD8⁺ ratio, IgG, IgM, IgA, and urine HCMV-DNA load between the breast milk HCMV positive and HCMV negative groups, as well as between the breast milk high viral load and low viral load subgroups (P>0.05). CONCLUSIONS Breastfeeding with HCMV does not affect the immune function of infants with HCMV infection.
Female ; Child ; Humans ; Infant ; Breast Feeding ; Cytomegalovirus Infections ; CD8-Positive T-Lymphocytes ; Retrospective Studies ; Infectious Disease Transmission, Vertical ; Milk, Human ; Cytomegalovirus ; Immunity ; Immunoglobulin A ; Immunoglobulin G ; Immunoglobulin M

Objective: To study the incubation period of the infection with 2019-nCoV Omicron variant BA.5.1.3. Methods: Based on the epidemiological survey data of 315 COVID-19 cases and the characteristics of interval censored data structure, log-normal distribution and Gamma distribution were used to estimate the incubation. Bayes estimation was performed for the parameters of each distribution function using discrete time Markov chain Monte Carlo algorithm. Results: The mean age of the 315 COVID-19 cases was (42.01±16.54) years, and men accounted for 30.16%. A total of 156 cases with mean age of (41.65±16.32) years reported the times when symptoms occurred. The log-normal distribution and Gamma distribution indicated that the M (Q₁, Q₃) of the incubation period from exposure to symptom onset was 2.53 (1.86, 3.44) days and 2.64 (1.91, 3.52) days, respectively, and the M (Q₁, Q₃) of the incubation period from exposure to the first positive nucleic acid detection was 2.45 (1.76, 3.40) days and 2.57 (1.81, 3.52) days, respectively. Conclusions: The incubation period by Bayes estimation based on log-normal distribution and Gamma distribution, respectively, was similar to each other, and the best distribution of incubation period was Gamma distribution, the difference between the incubation period from exposure to the first positive nucleic acid detection and the incubation period from exposure to symptom onset was small. The median of incubation period of infection caused by Omicron variant BA.5.1.3 was shorter than those of previous Omicron variants.
Male ; Humans ; Adult ; Middle Aged ; SARS-CoV-2 ; COVID-19 ; Bayes Theorem ; Infectious Disease Incubation Period ; Nucleic Acids

Objective: To understand the current status of fertility safety cognition among married HIV-infected people aged 18-45 years and to provide evidence for fertility safety intervention in HIV-infected families. Methods: Six districts in Chongqing and Zigong City in Sichuan Province were selected. A questionnaire survey was conducted among married HIV-infected people aged 18-45 years who were followed up from November 2021 to April 2022 to collect their general demographic characteristics, histories of sex experience, fertility intention, and knowledge of birth safety. Unconditional logistic regression and Poisson regression were used to analyze the factors affecting the cognition of birth safety. Results: A total of 266 HIV-infected people were included in the study; 58.3% (155/266) were women, and 48.9% (130/266) had fertility desire. The cognition rate of knowledge of birth safety was 59.4% (158/266). The cognition rate of women's knowledge of birth safety was 2.14 (95%CI: 1.25-3.66) times that of men's. The cognition rate of knowledge of birth safety among HIV-infected persons with a high school education level or above was 1.88 (95%CI: 1.08-3.27) times that of those with a low education level. The cognition rate of knowledge of reproductive safety among HIV-infected people with fertility intention was 1.88 (95%CI: 1.10-3.22) times that of those without fertility intention. The cognition rate of knowledge of birth safety among HIV-infected persons who received AIDS knowledge promotion and education was 9.06 (95%CI: 2.46-33.32) times that of those who did not. The cognition rate of measures of birth safety was 5.3% (14/266). The Poisson regression analysis showed no significant difference in the cognition rate of specific measures among gender, age, education and other factors. Conclusions: HIV-infected people aged 18-45 years and married with a spouse have a low awareness of birth safety, and there are risks of HIV transmission between couples and mother-to-child in the family. Targeted birth safety education and intervention should be strengthened to reduce HIV transmission.
Male ; Humans ; Female ; HIV Infections ; Spouses ; Infectious Disease Transmission, Vertical ; Fertility ; Surveys and Questionnaires ; Cognition

Humans ; Iran/epidemiology* ; Drug Users ; Disease Transmission, Infectious ; HIV Infections/epidemiology*

Objective To study the expression of selenoprotein genes in human immunodeficiency virus(HIV)infection and its mother-to-child transmission,so as to provide a theoretical basis for the prevention,diagnosis,and treatment of acquired immunodeficiency syndrome.Methods The dataset GSE4124 was downloaded from the Gene Expression Omnibus(GEO).Two groups of HIV-positive mothers(n=25)and HIV-negative mothers(n=20)were designed.HIV-positive mothers included a subset of transmitter(TR)mothers(n=11)and non-transmitter(NTR)mothers(n=14).Then,t-test was carried out to compare the expression levels of selenoprotein genes between the four groups(HIV-positive vs. HIV-negative,NTR vs. HIV-negative,TR vs. HIV-negative,TR vs. NTR).Univariate and multivariate Logistic regression were adopted to analyze the effects of differentially expressed genes on HIV infection and mother-to-child transmission.R software was used to establish a nomogram prediction model and evaluate the model performance.Results Compared with the HIV-negative group,HIV-positive,NTR,and TR groups had 8,5 and 8 down-regulated selenoprotein genes,respectively.Compared with the NTR group,the TR group had 4 down-regulated selenoprotein genes.Univariate Logistic regression analysis showed that abnormally high expression of GPX1,GPX3,GPX4,TXNRD1,TXNRD3,and SEPHS2 affected HIV infection and had no effect on mother-to-child transmission.The multivariate Logistic regression analysis showed that the abnormally high expression of TXNRD3(OR=0.032,95%CI=0.002-0.607,P=0.022)was positively correlated with HIV infection.As for the nomogram prediction model,the area under the receiver-operating characteristic curve for 1-year survival of HIV-infected patients was 0.840(95%CI=0.690-1.000),and that for 3-year survival of HIV-infected patients was 0.870(95%CI=0.730-1.000).Conclusions Multiple selenoprotein genes with down-regulated expression levels were involved in the regulation of HIV infection and mother-to-child transmission.The abnormal high expression of TXNRD3 was positively correlated with HIV infection.The findings provide new ideas for the prevention,diagnosis,and treatment of acquired immunodeficiency syndrome.
Humans ; Female ; HIV Infections ; Acquired Immunodeficiency Syndrome ; Infectious Disease Transmission, Vertical ; Nomograms ; Selenoproteins/genetics*

Objective: To analyze the association between different treatment timings and adverse neonatal outcomes (premature birth, death, congenital syphilis) in syphilis-infected pregnant women. Methods: The National Management Information System for Prevention of HIV, Syphilis and HBV Mother-to-Child Transmission was used to collect information on the detection and treatment of syphilis-infected pregnant women and their newborns in Guangdong Province from October 2011 to December 2021. According to the gestational weeks of syphilis-infected pregnant women receiving penicillin treatment for the first time, they were divided into four groups: treatment in the first trimester, treatment in the second trimester, treatment in the third trimester, and no treatment during pregnancy. Multivariate logistic regression was used to analyze the association between different treatment timings and adverse neonatal outcomes in syphilis-infected pregnant women. Results: A total of 22 483 syphilis-infected pregnant women were included. The number of pregnant women who started treatment in the first trimester, second trimester, and third trimester and did not receive treatment during pregnancy were 4 549 (20.23%), 8 719 (38.78%), 2 235 (9.94%) and 6 980 (31.05%), respectively. Compared with pregnant women who started treatment in the first trimester, pregnant women who did not receive anti-syphilis treatment during pregnancy had increased risks of neonatal preterm birth (OR=1.42, 95%CI: 1.24-1.62), death (OR=4.27, 95%CI: 1.64-14.69) and congenital syphilis (OR=12.26, 95%CI: 6.35-27.45). At the same time, the risk of congenital syphilis in the newborns of pregnant women who started anti-syphilis treatment in the second trimester (OR=2.68, 95%CI: 1.34-6.16) and third trimester (OR=6.27, 95%CI: 2.99-14.80) also increased. Conclusion: Early initiation of anti-syphilis treatment during pregnancy in patients with syphilis can improve neonatal outcomes.
Pregnancy ; Female ; Infant, Newborn ; Humans ; Pregnant Women ; Syphilis/diagnosis* ; Pregnancy Complications, Infectious/drug therapy* ; Syphilis, Congenital/drug therapy* ; Premature Birth ; Infectious Disease Transmission, Vertical/prevention & control*

Objective: To analyze the incidence and related factors of drug resistance in HIV-infected pregnant and postpartum women in some areas of three western provinces of China from 2017 to 2019. Methods: From April 2017 to April 2019, face-to-face questionnaires and blood sample testing were conducted in all health care institutions providing maternal and perinatal care and midwifery-assisted services in 7 prevention of mother-to-child transmissi project areas in Xinjiang, Yunnan and Guangxi provinces/autonomous regions. Information was collected during the perinatal period and viral load, CD4⁺T lymphocytes and drug resistance genes were detected at the same time. The multivariate logistic regression model was used to analyze the relationship between different factors and drug resistance in HIV-infected pregnant and postpartum women. Results: A total of 655 HIV-infected pregnant and postpartum women were included in this study. The incidence of drug resistance was 3.4% (22/655), all of whom were cross-drug resistant. The rate of low, moderate and high drug resistance was 2.1% (14/655), 1.2% (8/655) and 0.8% (5/655), respectively. The drug resistance rate in the people who had previously used antiviral drugs was 1.9% (8/418), and the drug resistance rate in the people who had not used drugs was 5.9% (14/237). The NNRTI drug resistance accounted for 2.8% (18/655) and the NRTI drug resistance rate was 2.5% (16/655). The multivariate logistic regression model showed that the risk of HIV resistance was lower in pregnant women who had previously used antiviral drugs (OR=0.32, 95%CI: 0.11-0.76). Conclusion: Strengthening the management of antiviral drug use and focusing on pregnant and postpartum women who have not previously used antiviral drugs can help reduce the occurrence of drug-resistant mutations. Personalized antiviral therapy should be considered to achieve viral inhibition effects in clinical practice.
Female ; Humans ; Pregnancy ; HIV Infections/drug therapy* ; Incidence ; China/epidemiology* ; Infectious Disease Transmission, Vertical/prevention & control* ; Postpartum Period ; Drug Resistance, Viral/genetics* ; Antiviral Agents/therapeutic use*

Objective: To analyze the association between different treatment timings and adverse neonatal outcomes (premature birth, death, congenital syphilis) in syphilis-infected pregnant women. Methods: The National Management Information System for Prevention of HIV, Syphilis and HBV Mother-to-Child Transmission was used to collect information on the detection and treatment of syphilis-infected pregnant women and their newborns in Guangdong Province from October 2011 to December 2021. According to the gestational weeks of syphilis-infected pregnant women receiving penicillin treatment for the first time, they were divided into four groups: treatment in the first trimester, treatment in the second trimester, treatment in the third trimester, and no treatment during pregnancy. Multivariate logistic regression was used to analyze the association between different treatment timings and adverse neonatal outcomes in syphilis-infected pregnant women. Results: A total of 22 483 syphilis-infected pregnant women were included. The number of pregnant women who started treatment in the first trimester, second trimester, and third trimester and did not receive treatment during pregnancy were 4 549 (20.23%), 8 719 (38.78%), 2 235 (9.94%) and 6 980 (31.05%), respectively. Compared with pregnant women who started treatment in the first trimester, pregnant women who did not receive anti-syphilis treatment during pregnancy had increased risks of neonatal preterm birth (OR=1.42, 95%CI: 1.24-1.62), death (OR=4.27, 95%CI: 1.64-14.69) and congenital syphilis (OR=12.26, 95%CI: 6.35-27.45). At the same time, the risk of congenital syphilis in the newborns of pregnant women who started anti-syphilis treatment in the second trimester (OR=2.68, 95%CI: 1.34-6.16) and third trimester (OR=6.27, 95%CI: 2.99-14.80) also increased. Conclusion: Early initiation of anti-syphilis treatment during pregnancy in patients with syphilis can improve neonatal outcomes.
Pregnancy ; Female ; Infant, Newborn ; Humans ; Pregnant Women ; Syphilis/diagnosis* ; Pregnancy Complications, Infectious/drug therapy* ; Syphilis, Congenital/drug therapy* ; Premature Birth ; Infectious Disease Transmission, Vertical/prevention & control*