Abstract In April 2021, type Ⅰ vaccine-derived poliovirus (VDPV) was detected from two fecal samples of a male infant with acute flaccid paralysis (AFP) in Zhejiang Province when he was admitted to the Children's Hospital Affiliated to Fudan University in Shanghai, with 12 and 14 nucleotide mutations in the VP1 region, respectively. The case had a history of immunization with three doses of poliovirus vaccines, and grade Ⅲ proximal muscle strength and grade Ⅱ distal muscle strength of the right lower limb. After symptomatic treatment, the activity of the right lower limb and the muscle strength was significantly restored, thus he was discharged. VDPV was not detected from subsequent (the 8th to 12th) fecal samples of the case and fecal samples of close contacts. No similar cases were found in medical institutions in the county, surrounding areas, neighboring villages or towns. Since the case did not exhibit clinical symptoms of poliomyelitis caused by VDPV, poliomyelitis was excluded, and the case was diagnosed with hemophilia type A based on the epidemiological investigation, laboratory tests, and the history of poliomyelitis vaccination. This event involved cross-provincial (municipal) cooperation and was responsed promptly, preventing further spread of the virus. It suggested that the sensitivity of the AFP case surveillance system should be maintained, environmental monitoring methods should be increased, and the poliomyelitis vaccination should be promoted to prevent the spread of the virus.

L-citrulline is a nonprotein amino acid that plays an important role in human health and has great market demand. Although microbial cell factories have been widely used for biosynthesis, there are still challenges such as genetic instability and low efficiency in the biosynthesis of L-citrulline. In this study, an efficient, plasmid-free, non-inducible L-citrulline-producing strain of Escherichia coli BL21(DE3) was engineered by combined strategies. Firstly, a chassis strain capable of synthesizing L-citrulline was constructed by block of L-citrulline degradation and removal of feedback inhibition, with the L-citrulline titer of 0.43 g/L. Secondly, a push-pull-restrain strategy was employed to enhance the L-citrulline biosynthesis, which realized the L-citrulline titer of 6.0 g/L. Thirdly, the NADPH synthesis and L-citrulline transport were strengthened to promote the synthesis efficiency, which achieved the L-citrulline titer of 11.6 g/L. Finally, fed-batch fermentation was performed with the engineered strain in a 3 L fermenter, in which the L-citrulline titer reached 44.9 g/L. This study lays the foundation for the industrial production of L-citrulline and provides insights for the modification of other amino acid metabolic networks.
Citrulline/biosynthesis* ; Escherichia coli/genetics* ; Metabolic Engineering/methods* ; Fermentation ; NADP/biosynthesis*

LINGO-1，a Nogo receptor-interacting protein-1 rich in leucine repeat sequences and immunoglobulin structural domains，which is specifically expressed in neurological diseases. In recent years，more and more evidences indicate that LINGO-1 plays an important role in glial scar formation，cell death and inflammatory reaction. LINGO-1 inhibits oligodendrocyte activation，and prevents axon and myelin formation and functional recovery，and is therefore considered to be a negative regulator of neuronal survival，neurite extension and axon myelination. The change of LINGO-1 level is related to the occurrence and development of many neurological diseases. This article reviews the physiological function of LINGO-1 and summarizes the latest research progress of LINGO-1 in multiple sclerosis，spinal cord injury，neonatal brain injury and epilepsy，so as to explore new strategies for the treatment of neurological diseases.

Vasoinhibitory vasovagal syncope（VVS-VI）in children is the most common type of responses in vasovagal syncope（VVS）and has a high incidence. VVS-VI is a recurrent disorder caused by a malfunctioning autonomic nervous system. VVS-VI can be caused by a variety of stimuli such as strong emotions，sudden changes in posture，hot and stuffy environments and prolonged standing. It was found that VVS-VI is a benign disease without organic lesions and is self-limiting and reversible，but VVS-VI children often suffer irreversible consequences due to secondary injuries. VVS-VI seriously affects the life and academic performance of children，endangers their physical and mental health，and causes anxiety among parents，so the number of studies on VVS-VI has increased in recent years. This article summarizes the progress of diagnostic research on VVS-VI in children，and provides a reference for related research.

Objective: To analyze the strengths, weaknesses, opportunities and threats of the construction on intelligent vaccination clinics in Zhejiang Province, so as to provide countermeasures for promoting the construction of intelligent vaccination clinics in Zhejiang Province. Methods: By reviewing the annual reports of Zhejiang immunization planning, survey data from Zhejiang Centers for Disease Control and Prevention and Immunization Intelligent Service System, data of human resources of immunization planning, vaccine procurement, construction progress of intelligent vaccination clinics and vaccination were collected. The relevant literature was searched to gather information on the construction standards and norms of intelligent vaccination clinics. The analysis of the strengths, weaknesses, opportunities and threats (SWOT) of the construction of intelligent vaccination clinics was conducted, and corresponding countermeasures and suggestions were proposed. Results: The National Immunization Program reported vaccine rate in Zhejiang Province is more than 99%, and standardized vaccination clinics have been popularized throughout the province. The vaccination staff are professional, and a province-wide intelligent immunization service information system has been established, providing the resources and conditions for the construction of intelligent vaccination clinics. However, there are problems such as low data quality and matching efficiency in vaccination, insufficient data interoperability and sharing, unbalanced regional capabilities in intelligent transformation, and uneven distribution of talent and resources. It is crucial to seize the opportunities presented by the development of big data and artificial intelligence, rely on the regional development of the Internet and health industry, seize the opportunity of rapid growth in demand for intelligent vaccination services and high public acceptance, accelerate the construction of intelligent vaccination clinics, and establish intelligent vaccination service standards as soon as possible. Conclusion We should seize the opportunities presented by the digital reform and development, fully utilize the existing vaccination resources and strengths, address the shortcomings, and accelerate the construction of intelligent vaccination clinics in Zhejiang Province.

BACKGROUND:Premature birth is a major global health problem associated with high mortality and morbidity.White matter injury is the most common brain injury in preterm infants.Salvia miltiorrhiza is a traditional herbal plant that is commonly used to treat cardiovascular and cerebrovascular diseases in Asian countries. OBJECTIVE:To investigate the therapeutic effect of Salvia miltiorrhiza on white matter injury in preterm infants. METHODS:Eighteen neonatal male Sprague-Dawley rats at 3-day gestational age were selected and randomized into normal group,white matter injury group,and Salvia miltiorrhiza group.Animal models of preterm white matter injury were established by permanent ligation of the right common carotid artery in the latter two groups.Rats in the Salvia miltiorrhiza group were given intraperitoneal injection of Salvia miltiorrhiza(5 mg/kg·d)for 7 consecutive days.Normal group and white matter injury group were given the same volume of PBS for intervention.On the 14th day after modeling,the rats were sacrificed.Brains were pathologically observed by hematoxylin-eosin staining under microscope,and the expression levels of myelin basic protein and CC1 in brain tissue were visualized using immunofluorescence.Furthermore,liquid chromatography-tandem mass spectrometry was used to analyze possible pathways for the action of Salvia miltiorrhiza. RESULTS AND CONCLUSION:In the white matter injury group,the structure of the corpus callosum was irregular and the cells appeared swollen and necrotic.In addition,induction of white matter injury resulted in significantly reduced myelin formation,with irregular and loosely arranged nerve fibers and significantly decreased myelin sheaths.Interestingly,white matter injury rats treated with Salvia miltiorrhiza had reduced cellular swelling,reduced lesions,and increased myelin sheaths.The expression of myelin basic protein was closely related to myelin formation,and CC1 was a marker of myelin oligodendrocytes.Salvia miltiorrhiza significantly up-regulated the expressions of myelin basic protein and CC1 in white matter injury rats(P＜0.000 1),indicating that Salvia miltiorrhiza alleviated white matter injury.Liquid chromatography-tandem mass spectrometry analysis showed that the therapeutic effect of Salvia miltiorrhiza in the rat model of white matter injury was closely related to the regulation of complement and coagulation cascades.To conclude,Salvia miltiorrhiza may be a potential therapeutic agent for treating preterm white matter injury.

Objective:To evaluate the epidemiological characteristics and explore the associated factors of breakthrough cases (BC) from Public Health Emergency Events (PHEEs) of varicella in Zhejiang Province from 2019 to 2022.Methods:Data on cases were obtained from the China Information System for Disease Control and Prevention and the PHEEs Reporting Information Database of Varicella in Zhejiang Province. History records were matched through the Zhejiang Provincial Immunization Information System. Descriptive analysis and multiple logistic regression model with a bidirectional stepwise selection method were performed to explore associated factors for BC during 2019-2022.Results:A total of 144 276 varicella cases were reported from 2019 to 2022, with the annual reported incidence of 47.35-82.80 cases per 100 000 population. Among these cases, 109 172 were non-breakthrough cases (NBC, accounting for 75.67%), 34 517 were BC (23.92%), and the rest 587 cases had unclear vaccination history on varicella (0.41%). A total of 214 PHEEs of varicella were reported, of which 99.07% occurred in school settings. The proportion of PHEEs that occurred in high school increased significantly as time went on ( χ2trend=5.742, P=0.017). Multiple logistic regression model which focused on "BC vs. NBC (as the reference)" indicated that the year of onset ( OR=1.585, 95% CI:1.343-1.878), the month of onset (taking January as the reference, OR=2.311-15.652), city (taking Hangzhou as the reference, Jiaxing OR=2.370, Jinhua OR=2.197, Lishui OR=0.134), age ( OR=0.887, 95% CI: 0.826-0.944), PHEEs setting (taking "primary school and below" as the reference, "high school and above" OR=0.516, 95% CI: 0.305-0.897), and the number of rashes ( OR=0.569, 95% CI: 0.458-0.703) were associated factors. Multiple logistic regression model which focused on "two-dose BC vs. one-dose BC (as the reference)" showed that the age of initial vaccination ( OR=0.045, 95% CI: 0.014-0.107), the time interval from onset to the last dose ( OR=0.037, 95% CI: 0.011-0.087) and the age of onset ( OR=20.724, 95% CI: 8.383-72.485) were associated factors. Conclusion:During 2019-2022, the reported high-risk group of varicella in Zhejiang Province has shifted to adolescents and young adults. Although vaccination could not completely prevent the onset of VZV, it could relieve clinical symptoms and delay the age of onset.

Objective:To evaluate the epidemiological characteristics and explore the associated factors of breakthrough cases (BC) from Public Health Emergency Events (PHEEs) of varicella in Zhejiang Province from 2019 to 2022.Methods:Data on cases were obtained from the China Information System for Disease Control and Prevention and the PHEEs Reporting Information Database of Varicella in Zhejiang Province. History records were matched through the Zhejiang Provincial Immunization Information System. Descriptive analysis and multiple logistic regression model with a bidirectional stepwise selection method were performed to explore associated factors for BC during 2019-2022.Results:A total of 144 276 varicella cases were reported from 2019 to 2022, with the annual reported incidence of 47.35-82.80 cases per 100 000 population. Among these cases, 109 172 were non-breakthrough cases (NBC, accounting for 75.67%), 34 517 were BC (23.92%), and the rest 587 cases had unclear vaccination history on varicella (0.41%). A total of 214 PHEEs of varicella were reported, of which 99.07% occurred in school settings. The proportion of PHEEs that occurred in high school increased significantly as time went on ( χ2trend=5.742, P=0.017). Multiple logistic regression model which focused on "BC vs. NBC (as the reference)" indicated that the year of onset ( OR=1.585, 95% CI:1.343-1.878), the month of onset (taking January as the reference, OR=2.311-15.652), city (taking Hangzhou as the reference, Jiaxing OR=2.370, Jinhua OR=2.197, Lishui OR=0.134), age ( OR=0.887, 95% CI: 0.826-0.944), PHEEs setting (taking "primary school and below" as the reference, "high school and above" OR=0.516, 95% CI: 0.305-0.897), and the number of rashes ( OR=0.569, 95% CI: 0.458-0.703) were associated factors. Multiple logistic regression model which focused on "two-dose BC vs. one-dose BC (as the reference)" showed that the age of initial vaccination ( OR=0.045, 95% CI: 0.014-0.107), the time interval from onset to the last dose ( OR=0.037, 95% CI: 0.011-0.087) and the age of onset ( OR=20.724, 95% CI: 8.383-72.485) were associated factors. Conclusion:During 2019-2022, the reported high-risk group of varicella in Zhejiang Province has shifted to adolescents and young adults. Although vaccination could not completely prevent the onset of VZV, it could relieve clinical symptoms and delay the age of onset.

OBJECTIVES: Several countries have successfully eliminated measles, and China is making significant strides toward achieving this goal. This study focused on investigating the patterns of measles infections in Zhejiang Province, China, as well as control measures. The objective was to provide valuable insights that could contribute to the development of nationwide elimination strategies. METHODS: We analyzed measles surveillance data from 2005 to 2022 in Zhejiang Province. We utilized a joinpoint regression model to examine trends in measles. Additionally, we employed SaTScan version 9.5 to identify spatial-temporal clusters. Finally, we used an age-period-cohort model to assess the effects of age, period, and cohort. RESULTS: The age-standardized incidence rate (ASIR) of measles infection in Zhejiang Province from 2005 to 2022 was 5.24 per 100,000, showing a consistent and significant downward trend with an annual percentage change of -24.93% (p<0.05). After 2020, the ASIR for measles infection fell to below 0.1 per 100,000. The majority of measles cases occurred in individuals either without an immunization history or with an unknown immunization status, representing 41.06% and 41.40% of the cases from 2010 to 2022, respectively. According to data from the National Measles Surveillance System, the annual rate of discarded measles cases from 2009 to 2014, and the annual rate of discarded measles and rubella cases from 2015 to 2022, were both above 2 per 100,000, indicating the high sensitivity of the measles surveillance system. CONCLUSIONS The significant reduction in measles incidence from 2005 to 2022 demonstrates substantial progress in Zhejiang Province towards the elimination of measles.

OBJECTIVES: Several countries have successfully eliminated measles, and China is making significant strides toward achieving this goal. This study focused on investigating the patterns of measles infections in Zhejiang Province, China, as well as control measures. The objective was to provide valuable insights that could contribute to the development of nationwide elimination strategies. METHODS: We analyzed measles surveillance data from 2005 to 2022 in Zhejiang Province. We utilized a joinpoint regression model to examine trends in measles. Additionally, we employed SaTScan version 9.5 to identify spatial-temporal clusters. Finally, we used an age-period-cohort model to assess the effects of age, period, and cohort. RESULTS: The age-standardized incidence rate (ASIR) of measles infection in Zhejiang Province from 2005 to 2022 was 5.24 per 100,000, showing a consistent and significant downward trend with an annual percentage change of -24.93% (p<0.05). After 2020, the ASIR for measles infection fell to below 0.1 per 100,000. The majority of measles cases occurred in individuals either without an immunization history or with an unknown immunization status, representing 41.06% and 41.40% of the cases from 2010 to 2022, respectively. According to data from the National Measles Surveillance System, the annual rate of discarded measles cases from 2009 to 2014, and the annual rate of discarded measles and rubella cases from 2015 to 2022, were both above 2 per 100,000, indicating the high sensitivity of the measles surveillance system. CONCLUSIONS The significant reduction in measles incidence from 2005 to 2022 demonstrates substantial progress in Zhejiang Province towards the elimination of measles.