[Theoretical models for influenza vaccination behavior at the individual level]

Influenza imposes a significant disease burden on society and individuals annually, and influenza vaccination is considered a significant public health measure to prevent influenza and reduce influenza-related severe disease and death. The low influenza vaccination rate in China is partly due to certain factors affecting the willingness and behavior of individuals to receive them. Scientific research and targeted interventions on these factors can effectively improve the vaccination situation. Commonly used individual-level theoretical models for influenza vaccination behavior include the health belief model, protection motivation theory, and theory of planned behavior. This study reviews theoretical models commonly employed in researching influenza vaccination willingness and behavior. An overview of these practical applications and challenges models is presented to provide references for relevant research and intervention programs in China.

[Progress in research of influenza vaccination in pregnant women]

Influenza is an acute respiratory infectious disease caused by influenza virus. Pregnancy is associated with physiologic and immunological changes that may increase the risk for influenza virus infection and influenza-related complications. Influenza vaccination is the most effective way to prevent influenza virus infection. WHO and many countries have classified pregnant women as a priority population for influenza vaccination, however, there are still many challenges for promoting influenza vaccination in pregnant women in China, influenza vaccination coverage in pregnant women remains low and some influenza vaccine package inserts list pregnancy as an absolute contraindication. In this paper, we summarize the research progress in the effects of influenza infection and influenza vaccination during pregnancy both at home and abroad, then discuss the strategies to promote influenza vaccination in pregnancy for the purpose of providing reference for the related research and policy development in China.

[Thoughts and suggestions on co-administration of seasonal influenza vaccine and COVID-19 vaccine]

In the context of the global pandemic of COVID-19, the epidemic intensity, epidemic characteristics and infection risk of influenza have presented new features. COVID-19 and influenza have simultaneously emerged in many regions of the world. COVID-19 and influenza are similar in terms of transmission mode, clinical symptoms and other aspects. There are also similarities in the mechanism of influenza virus and novel coronavirus on cells. At the same time, it is feasible and significant to do a good job in the prevention and control of COVID-19 and influenza. This paper discusses the relevant strategies and measures for the joint prevention and control of influenza and novel coronavirus from the aspects of influenza vaccination to prevent co-infection, simultaneous vaccination of influenza vaccine and novel coronavirus vaccine, etc., and puts forward corresponding thoughts and suggestions, in order to provide scientific support for the formulation of strategies on seasonal influenza vaccine and novel coronavirus vaccination.

[Financing strategies and cost estimates of influenza vaccination for the elderly in China: explore a multi-party co-payment mechanism]

The disease burden and economic burden of seasonal influenza is substantial in China, and the Coronavirus disease 2019 (COVID-19) pandemic has brought new challenges to the prevention and control of influenza. As a priority group of influenza vaccination, the elderly are at higher risk of influenza-associated severe symptoms and deaths, and they are more price-sensitive vaccine users with better cost-effectiveness of vaccination program. Therefore, a reasonable financing mechanism of influenza vaccination should be designed for the elderly to increase their vaccination rate. This study proposes three financing strategies of influenza vaccination for the elderly in China, trying to explore the distribution of vaccination costs among individuals, central government and local governments under different financing strategies, including the individual-central-local mechanism (strategy 1), the central-local mechanism (strategy 2), and the local payment mechanism (strategy 3). Strategy 1 is feasible and sustainable for most regions in the short term. Strategy 2 is conducive to further increasing the vaccine coverage rate of the elderly. Strategy 3 encourages local fiscal payments to help relieve the financial pressure of the central government. The results revealed a relatively heavy financial burden of influenza vaccination for the elderly, and it is recommended to promote the development of a multiparty co-payment mechanism gradually based on local conditions.

[Analysis of the time for observation and related factors at clinics after vaccination among children's parents]

Objective: To understand the time for observation and related factors in the clinics after vaccination among children's parents. Methods: From December 2019 to January 2020, parents of children aged 0-3 years were recruited by multiple-stage sampling from 34 vaccination clinics in 12 districts and counties in 6 provinces (Shandong, Guangdong, Henan, Sichuan, Inner Mongolia, and Liaoning). A questionnaire survey on the time of observation after vaccination was conducted. A multivariate logistic regression model was used to analyze the related factors of parental observation time after vaccination. Results: A total of 3 292 parents of 0-3 year's old children were selected, and 3 178 parents were finally included in the analysis. 87.85%(2 792/3 178) of the parents reported that the observation time after vaccination at clinics was ≥30 minutes. Multivariate logistic regression analysis showed that, after adjusting for the regions, the main factors affecting the observation time at clinics after vaccination among parents appeared as observation time informed by physicians at the clinic appeared ≥30 minutes (OR=31.622, 95%CI: 19.847-50.384), parents were medical personnel (OR=2.779, 95%CI: 1.505-5.133), parents being volunteers working on vaccination-related publicity and education activities (OR=1.986, 95%CI: 1.438-2.743), parents aged 35 years old or above (OR=1.900, 95%CI: 1.215-2.971), being parents of the first child (OR=1.663, 95%CI: 1.282-2.156), per capita annual income of the family as 8 000- Yuan (OR=1.646, 95%CI: 1.168-2.319), children aged 0-12 months old (OR=1.646, 95%CI: 1.203-2.252) or 13-24 months old (OR=1.506, 95%CI: 1.064-2.133), obedient to physicians' advice at the clinic (OR=1.481, 95%CI: 1.067-2.055). Conclusions: The proportions of parents observed for ≥30 minutes at the clinics of vaccination were high. When the information was from the physicians at the vaccination clinic, the observation time was the most critical factor for parents to observe at clinics as required.

Nephroprotective effect of gastrodin against lead-induced oxidative stress and inflammation in mice by the GSH, Trx, Nrf2 antioxidant system, and the HMGB1 pathway

Gastrodin (GAS), the main phenolic glycoside derivative from Gastrodiaelata Blume, has several bio-activities. However, the molecular mechanisms of these protective actions currently remain unclear. This study aimed to investigate the mechanisms of GAS on lead (Pb)-induced oxidative stress and inflammation in the kidneys and primary kidney mesangial cells. Results indicated that GAS improved Pb-induced renal dysfunction and morphological changes in mice. GAS ameliorated Pb-induced inflammation in kidneys by reducing the TNF-α and IL-6 levels. GAS inhibited Pb-induced oxidative stress by regulating the glutathione, thioredoxin (Trx), and Nrf2 antioxidant systems. Furthermore, GAS supplementation increased the activation of SOD, GPx, HO-1, and NQO1 in the kidneys. GAS decreased the expression levels of HMGB1, TLR4, RAGE, MyD88, and NF-κB. These results were further confirmed in primary kidney mesangial cells. Collectively, this study demonstrated that GAS alleviated Pb-induced kidney oxidative stress and inflammation by regulating the antioxidant systems and the Nrf2 signaling pathway. Highlights Gastrodin ameliorated Pb-induced kidney injury in mice.Gastrodin inhibited oxidative stress and inflammation in kidneys.Gastrodin activated the GSH, Trx and Nrf2 antioxidant system in kidneys.Gastrodin inhibited the activities of HMGB1. RAGE, TLR4, and MyD88.

[Advance on the infectivity of SARS-CoV-2 infection at different stages]

The studies on infectiousness of person infected with SARS-CoV-2 at different stages of illness are an important basis for making effective prevention and control measures such as investigating the infectious source, determining the scope of close contacts and the timing of case isolation. This review discusses the infectiousness of cases infected with SARS-CoV-2 in the incubation period, symptomatic period and convalescent period by reviewing national and international literatures, technical and professional guidelines. Existing researches suggest that the infectious viruses could be isolated at the end of the incubation period as well as since illness onset, and viral load in upper respiratory tract swabs reached the peak on day 4-6 after illness onset and thereafter began to decline, implying the infectiousness was relatively strong at the end of incubation period and within one week after illness onset. Although there were a few cases who tested positive for SARS-CoV-2 after recovery, no evidence was found to indicate these cases can cause the transmission.

[Epidemiological study design of asymptomatic infection of the 2019 novel coronavirus]

COVID-19 is caused by the 2019 novel coronavirus (2019-nCoV). COVID-19 clinical cases are considered as the principal source of infection, however, asymptomatic cases may also play a role in the transmission. Significant gap exists in terms of the proportion or prevalence and transmissibility of asymptomatic cases. This study design plans to use data from areas with different epidemiological profiles to investigate the COVID-19 epidemic in China. In each selected region, both general community residents and key populations at high risk of COVID-19 infection, including recovered COVID-19 cases, close contacts of confirmed COVID-19 cases, medical professionals, investigators at CDCs, and visitors to fever clinics, will be recruited and examined for viral RNA of 2019-nCoV and serum antibodies. Prevalence and characterization of asymptomatic cases will be determined, stratified by varied demographics and exposure risk. During the follow-up, the change in the serum antibodies will be studied prospectively in the symptomatic and asymptomatic cases to address the scientific and public health concerns of infectivity and transmissibility of 2019-nCoV.

[Early containment strategies and core measures for prevention and control of novel coronavirus pneumonia in China]

In December 2019, novel coronavirus pneumonia epidemic occurred in Wuhan, Hubei Province, and spread rapidly across the country. In the early stages of the epidemic, China adopted the containment strategy and implemented a series of core measures around this strategic point, including social mobilization, strengthening case isolation and close contacts tracking management, blocking epidemic areas and traffic control to reduce personnel movements and increase social distance, environmental measures and personal protection, with a view to controlling the epidemic as soon as possible in limited areas such as Wuhan. This article summarizes the background, key points and core measures in the country and provinces. It sent prospects for future prevention and control strategies.

[Strengthen operational researches on influenza polices, and promote influenza vaccination in China]

This year of 2019 is the 10(th) anniversary of the 2009 H1N1 influenza pandemic, and a series of paper on epidemiology, disease burden, vaccine usage and adverse events following immunization (AEFI) incidences, cost-effectiveness of influenza vaccination, are forming an important topic of "influenza disease burden and vaccine policies" in this journal, which provide evidences and options for China's influenza prevention and control. We should continue to strengthen the operational researches on influenza prevention and control polices, increase the influenza vaccine coverage in high-risk groups, and improve the capacities of control and pandemic preparedness.

The function of microRNA-34a in osteoarthritis

AIM

To discuss the effects and mechanism of microRNA-34a in cell apoptosis induced by osteoarthritis.

METHODS

Collection of the normal and osteoarthritis synovial tissues and measurements of the miRNA-34a and TGIF2 gene expression. In the cell experiment, the cells were divided into Control, Blank and miRNA inhibitor group. The cell proliferation and apoptosis of the different groups were measured by MTT and flow cytometry and the TGIF2 protein expression in the different groups was evaluated by WB assay. The correlation between TGIF2 and miRNA-34a was analyzed by Double luciferase experiment.

RESULTS

Compared with normal synovial tissues, the miRNA-34a gene expression was significantly up-regulated and TGIF2 gene expression was significantly suppressed in osteoarthritis synovial tissues (p < 0.001, respectively). The cell proliferation was significantly depressed and the cell apoptosis rate was significantly increased in miRNA inhibitor group compared with the Control group (p < 0.001, respectively). Using the WB assay it was shown that the TGIF2 protein expression of miRNA inhibitor group was significantly suppressed compared with that of Control group (p < 0.01). By Double luciferase assay, TGIF2 gene was one target gene of miRNA-34a.

CONCLUSION

miRNA-34a could induce osteoarthritis synovial cell apoptosis via regulation of TGIF2 in vitro (Fig. 6, Ref. 29).

[Technical guidelines for seasonal influenza vaccination in China, 2018-2019]

Seasonal influenza vaccination is the most effective way to prevent influenza virus infection and its complications. Currently, China has licensed trivalent (IIV3) and quadrivalent inactivated influenza vaccine (IIV4), including split-virus influenza vaccine and subunit vaccine. In most parts of China, influenza vaccine is a category Ⅱ vaccine, which means influenza vaccination is voluntary, and recipients need to pay for it. To strengthen the technical guidance for prevention and control of influenza and the operational research on influenza vaccination in China, the National Immunization Advisory Committee (NIAC), Influenza Vaccine Technical Working Group (TWG), updated the 2014 technical guidelines and compiled the "Technical guidelines for seasonal influenza vaccination in China (2018-2019)" , based on most recent existing scientific evidences. The main updates include: epidemiology and disease burden of influenza, types of influenza vaccines, northern hemisphere influenza vaccination composition for the 2018-2019 season, and, IIV3 and IIV4 vaccines'major immune responses, durability of immunity, immunogenicity, vaccine efficacy, effectiveness, safety, cost-effectiveness and cost-benefit. The recommendations include: Points of Vaccination clinics (PoVs) should provide influenza vaccination to all persons aged 6 months and above who are willing to be vaccinated and do not have contraindications. No preferential recommendation is made for any influenza vaccine product for persons who can accept ≥1 licensed, recommended, and appropriate products. To decrease the risk of severe infections and complications due to influenza virus infection among high risk groups, the recommendations prioritize seasonal influenza vaccination for children aged 6-60 months, adults ≥60 years of age, persons with specific chronic diseases, healthcare workers, the family members and caregivers of infants <6 months of age, and pregnant women or women who plan to pregnant during the influenza season. Children aged 6 months to 8 years old require 2 doses of influenza vaccine administered a minimum of 4 weeks apart during their first season of vaccination for optimal protection. If they were vaccinated in previous influenza season, 1 dose is recommended. People ≥ 9 years old require 1 dose of influenza vaccine. It is recommended that people receive their influenza vaccination by the end of October. Influenza vaccination should be offered as soon as the vaccination is available. Influenza vaccination should continue to be available for those unable to be vaccinated before the end of October during the whole season. Influenza vaccine is also recommended for use in pregnant women during any trimester. These guidelines are intended for CDC members who are working on influenza control and prevention, PoVs members, healthcare workers from the departments of pediatrics, internal medicine, and infectious diseases, and members of maternity and child care institutions at all levels.

[Technical guidelines for seasonal influenza vaccination in China (2018-2019)]

Seasonal influenza vaccination is the most effective way to prevent influenza virus infection and complications from infection. Currently, China has licensed trivalent inactivated influenza vaccine (IIV3) and quadrivalent inactivated influenza vaccine (IIV4), including split-virus influenza vaccine and subunit vaccine. Except for a few major cities, influenza vaccine is a category Ⅱ vaccine, which means influenza vaccination is voluntary, and recipients must pay for it. To strengthen the technical guidance for prevention and control of influenza and operational research on influenza vaccination in China, the National Immunization Advisory Committee (NIAC) Influenza Vaccine Technical Working Group (TWG), updated the 2014 technical guidelines and compiled the "Technical guidelines for seasonal influenza vaccination in China (2018-2019)" . The main updates in this version include: epidemiology, disease burden, types of influenza vaccines, northern hemisphere influenza vaccination composition for the 2018-2019 season, IIV3 and IIV4 immune response, durability of immunity, immunogenicity, vaccine efficacy, effectiveness, safety, cost-effectiveness and cost-benefit. The influenza vaccine TWG provided the recommendations for influenza vaccination for the 2018-2019 influenza season based on existing scientific evidence. The recommendations described in this report include the following: Points of Vaccination clinics (PoVs) should provide influenza vaccination to all persons aged 6 months and above who are willing to be vaccinated and do not have contraindications. No preferential recommendation is made for one influenza vaccine product over another for persons for whom more than one licensed, recommended, and appropriate product is available. To decrease the risk of severe infections and complications due to influenza virus infection among high risk groups, the recommendations prioritize seasonal influenza vaccination for children aged 6-59 months, adults ≥60 years of age, persons with specific chronic diseases, healthcare workers, the family members and caregivers of infants <6 months of age, and pregnant women or women who plan to become pregnant during the influenza season. Children aged 6 months through 8 years require 2 doses of influenza vaccine administered a minimum of 4 weeks apart during their first season of vaccination for optimal protection. If they were vaccinated in 2017-2018 influenza season or a prior season, 1 dose is recommended. People more than 8 years old require 1 dose of influenza vaccine. It is recommended that people receive their influenza vaccination by the end of October. Influenza vaccination should be offered as soon as the vaccination is available. For the people unable to be vaccinated before the end of October, influenza vaccination will continue to be offered for the whole season. Influenza vaccine is also recommended for use in pregnant women during any trimester. These guidelines are intended for use by staff members of the Centers for Disease Control and Prevention at all levels who work on influenza control and prevention, PoVs staff members, healthcare workers from the departments of pediatrics, internal medicine, and infectious diseases, and staff members of maternity and child care institutions at all levels.

[Seasonal, avian and pandemic influenza: are we prepared?]

China experienced a very high and severe influenza seasonal epidemics during the past winter and spring of 2017-2018 season. This year of 2018 is the 100(th) anniversary of the 1918 "Spanish influenza" pandemic, a series of papers under the topic "One Hundred Years of Influenza Pandemics" are produced to demonstrate the impact, characteristics and responses of the past influenza pandemics in global and China, to review the progress and experiences of influenza surveillance, prevention and control strategies, vaccination and antivirus in China, and to discuss the gap and challenges of the prevention, control and response to the seasonal influenza, human avian influenza infection and influenza pandemics. We hope this series could help to raise the awareness of the seasonal and pandemic influenza in publics, and to improve the pandemic preparedness in China.

miRNA-31 over-expression improve synovial cells apoptosis induced by RA

OBJECTIVE

The aim of this study was to evaluate the effects and mechanism of miRNA-31 in synovial cells apoptosis induced by RA.

METHODS

The miRNA-31 gene expressions were extracted from synovial tissues of normal and RA patients by RT-PCR and H et E staining. The synovial cells of RA patients were isolated and randomly divided into Control, Blank and miRNA groups. The cell apoptosis of difference groups were measured by flow cytometry; the TNF-α and IL-1β concentrations of difference groups were measured by Elisa assay; TLR4 and NF-κB proteins expressions were measured by WB assay and the correlation between TLR4 and miRNA-31 were evaluated by double luciferase target experiment.

RESULTS

The miRNA-31 gene expression was significantly suppressed in RA tissues (p<0.001); Compared with control group, the cell apoptosis rate of miRNA group was significantly suppressed (p<0.001); TNF-α and IL-1β concentrations were significantly down-regulation in culture fluid (p<0.001, respectively) and TLR4 and NF-κB proteins expressions were significantly depressed (p<0.001, respectively) in miRNA group. By double luciferase target experiment, the TLR4 was a target gene of miRNA-31.

CONCLUSION

miRNA-31 is a key role in synovial cells apoptosis induced by RA (Fig. 7, Ref. 23).

Dihydromyricetin Inhibits Lead-Induced Cognitive Impairments and Inflammation by the Adenosine 5'-Monophosphate-Activated Protein Kinase Pathway in Mice

Dihydromyricetin (DHM), a natural flavonoid derived from the medicinal and edible plant Ampelopsis grossedentata, exhibits antioxidant, antiapoptosis, antitumor, and anti-inflammatory bioactivities. This study evaluated the effects of DHM on Pb-induced neurotoxicity and explored the underlying mechanisms. DHM significantly ameliorated behavioral impairments of Pb-induced mice. It decreased the levels of lipid peroxidation and protein carbonyl and increased the activities of superoxide dismutase and catalase in the brains. DHM suppressed Pb-induced apoptosis, as indicated by the decreased levels of Bax and cleaved caspase-3. DHM also decreased inflammatory cytokines in the brains of Pb-treated mice. DHM decreased amyloid-beta (Aβ) level and nuclear factor-κB nuclear translocation. Moreover, DHM induced the adenosine 5'-monophosphate-activated protein kinase (AMPK) phosphorylation and inhibited the activation of p38, Toll-like receptor 4, myeloid differentiation factor 88, and glycogen synthase kinase-3. Collectively, this is the first report indicating that DHM could improve Pb-induced cognitive functional impairment by preventing oxidative stress, apoptosis, and inflammation and that the protective effect was mediated partly through the AMPK pathway.

Association of changes in ER stress-mediated signaling pathway with lead-induced insulin resistance and apoptosis in rats and their prevention by A-type dimeric epigallocatechin-3-gallate

A-type dimeric epigallocatechin-3-gallate (A-type-EGCG-dimer, AEd), a new proanthocyanidins dimer from persimmon fruits, has been shown to have health benefit effects. However, A-type-EGCG-dimer affects gluose metabolism in the liver and the underlying mechanism is not clarified. The present study aims to examine the protective effects of A-type-EGCG-dimer on Pb-induced hepatic insulin resistance, endoplasmic reticulum (ER) stress and apoptosis in rats. Male wistar rats exposed to 0.05% w/v Pb acetate in the drinking water with or without A-type-EGCG-dimer coadministration (200 mg/kg body weight/day, intragastrically) for three months. We found that A-type-EGCG-dimer and pioglitazone supplementation significantly deceased glucose and insulin levels in plasma as compared with the Pb group. A-type-EGCG-dimer markedly prevents Pb-induced oxidative stress, ER stress and apoptosis in livers. A-type-EGCG-dimer and pioglitazone reduced the expression levels of the GRP78, PEPCK, G6Pase, p-PERK, p-IRE1, p-JNK, ATF4, CHOP and increased p-AKT in livers of the Pb group. Moreover, A-type-EGCG-dimer reduced ROS production and restored the activities of SOD and GPx in livers. A-type-EGCG-dimer decreased Bax, cytosolic cytochrome c and cleaved caspase-3 and increased Bcl-2 in livers of Pb-exposed rats. Our results suggest that A-type-EGCG-dimer might be a potential natural candidate for the prevention of hepatic insulin resistance and apoptosis induced by Pb.

Wolbachia Infection Dynamics in Tribolium confusum (Coleoptera: Tenebrionidae) and Their Effects on Host Mating Behavior and Reproduction

Wolbachia interact with their hosts in a broad variety of relationships that range from parasitism to mutualism. To improve the understanding of complex relationships between Wolbachia and host, we performed not only mating and crossing experiments to investigate effects of Wolbachia on mate choice, mating performance, and reproduction in the confused flour beetles Tribolium confusum (Jacquelin du Val), but also quantitative PCR to determine Wolbachia spatiotemporal infection density dynamics within beetles. Wolbachia induced strong cytoplasmic incompatibility, but had no effects on male mate choice and mating performance. Compared with Wolbachia-uninfected females, infected females had very high fecundity irrespective of male's infection status. Wolbachia infection densities in beetles were higher in eggs and adults and in the reproductive tissues and abdomens, whereas Wolbachia density in adults did not differ between sexes and among different ages. These results suggest that Wolbachia have evolved mutualistic interactions with T. confusum, which provides the first evidence of Wolbachia mutualisms in this beetle species. We discussed these findings and their evolutionary implications in light of Wolbachia-host interactions.

Proanthocyanidins improves lead-induced cognitive impairments by blocking endoplasmic reticulum stress and nuclear factor-κB-mediated inflammatory pathways in rats

Proanthocyanidins (PCs), a class of naturally occurring flavonoids, had been reported to possess a variety of biological activities, including anti-oxidant, anti-tumor and anti-inflammatory. In this study, we examined the protective effect of PCs against lead-induced inflammatory response in the rat brain and explored the potential mechanism of its action. The results showed that PCs administration significantly improved behavioral performance of lead-exposed rats. One of the potential mechanisms was that PCs decreased reactive oxygen species production and increased the total antioxidant capacity in the brains of lead-exposed rats. Furthermore, the results also showed that PCs significantly decreased the levels of tumor necrosis factor-α, interleukin 1β and cyclooxygenase-2 in the brains of lead-exposed rats. Moreover, PCs significantly decreased the levels of beta amyloid and phosphorylated tau in the brains of lead-treated rats, which in turn inhibited endoplasmic reticulum (ER) stress. PCs also decreased the phosphorylation of protein kinase RNA-like ER kinase, eukaryotic translation initiation factor-2, inositol-requiring protein-1, c-Jun N-terminal kinase, p38 and inhibited nuclear factor-κB nuclear translocation in the brains of lead-exposed rats. In conclusion, these results suggested that PCs could improve cognitive impairments by inhibiting brain oxidative stress and inflammatory response.

Nickel-induced oxidative stress and apoptosis in Carassius auratus liver by JNK pathway

Nickel (Ni) is ubiquitous in the biosphere and is a common component of natural fresh waters. When present in high concentrations, it becomes toxic to aquatic organisms. It is known that Ni toxicity may induce oxidative stress and apoptosis. However, the precise mechanism and the pathways that are activated in fish are still unclear. Thus, this study aimed to assess which apoptotic pathways are triggered by Ni in Carassius auratus liver, the main target of waterborne pollutants. Fish were exposed to 10, 25, 50 and 100mg/L of nickel sulfate for 96 h. Our data showed that Ni exposure caused fish weight loss (by 10-12%) and decreased locomotory activity (by 1-25%). Ni exposure significantly decreased the relative lymphocyte count (by 1-24%) and increased the relative count of monocytes (by 25-111%) and neutrophils (by 10-322%) as compared to controls. Ni induced oxidative stress, as evidenced by increasing of lipid peroxidation level (29-91%) and depleting of the glutathione levels (7-79%) in fish liver. Ni also suppressed the activities of superoxide dismutase (by 39-55%) and glutathione peroxidase (16-24%) and decreased ATP levels (13-51%) in livers. Moreover, liver caspase-3, one of the key executioners of apoptosis, was markedly activated by the Ni exposure. Ni exposure also increased expression levels of phosphorylated Jun N-terminal kinases (JNK) in liver, which in turn activated pro-apoptotic signaling events by breaking the balance between pro-apoptotic and anti-apoptotic Bcl-2 proteins. In conclusion, these results suggested that Ni induced oxidative stress and apoptosis, at least, via the JNK signaling pathway.

Detection of human cytomegalovirus in the atherosclerotic cerebral arteries in Han population in China

The association of atherosclerosis (AS) and Human cytomegalovirus (HCMV) infection was studied. AS plays an important role in the brain stroke and HCMV infection is supposed to be involved in the process of atherosclerotic formation. The presence of HCMV DNA and antigens was examined in the internal carotid arteries collected from 35 patients with ischemic stroke and from 20 patients from the control population. All patients belonged to the ethnic Han population in China. Three methods, immunohistochemistry (IHC), hybridization in situ (HIS), and PCR were used to detect the HCMV immediate early (IE) and late (L) antigens as well as viral DNA in vessel walls. Levels of HCMV IE gene/protein were significantly higher in the stroke group than in control group detected by the three methods (IHC 34.3% vs. 10.0%; HIS 40.0% vs. 10.0; PCR 60.0% vs. 30.0%). However, there was no significant difference in the levels of HCMV L gene/protein between these two groups of patients (IHC 11.4% vs. 5.0%; HIS 11.4% vs. 10.0%; PCR 20.0% vs. 20.0%). We concluded that the presence of HCMV IE antigen and HCMV DNA in the vessel wall was associated with the pathological process of AS formation.

Herpes simplex virus 1 inhibits apoptosis through a caspase-3-dependent pathway in primary cultures of cortical neuronal cells of fetal mice

We could induce apoptosis in primary cultures of cortical neurons of fetal mice with ceramide or sorbitol. The induction was accompanied by an increase in caspase-3 (CAS-3) activity and depolarization of the inner mitochondrial membrane of neuronal cells which both could be reversed by Herpes simplex virus 1 (HSV-1) infection. We conclude tha HSV-1 infection inhibited the apoptosis, induced in neuronal cells by sorbitol or ceramide, via a CAS-dependent pathway.

[Studies on the Robertsonian translocation of Microtus mandarinus]

The type of chromosome No. 1 and chromosome number from 53 individuals of Microtus mandarinus have been studied and compared in three sex types: XY, XX, XO. We found that the first pair of autosomes are very unstable, and there are three types: (1) M, M (With a double metacentric chromosome), (2) M, T, T, (With single metacentric chromosome). (3) T, T, T, T (Without metacentric chromosome). The chromosome number of the same sex individuals changes regularly with the type change of chromosome No. 1, that is, the increase of one chromosome in 2n number is always accompanied by the increase of two T and the decrease of one M, and vice versa. The synaptonemal complexes (SCs) of spermatocyte in pachytene nuclei from the males (2n = 51) were analysed by the electron microscopy. The SCs studies demonstrate that there are 23 fully paired autosomal bivalents, XY-bivalent and an autosomal trivalent. This trivalent is formed by one metacentric and two telocentric elements and characterized by the presence of two short side-arms. Meanwhile, all trivalents are in a cis configuration. The study of G-banding also demonstrates that the No. 1 autosome polymorphism is caused by Robertsonian translocation. Robertsonian fission is the main reason of the polymorphism of chromosome No. 1 and of variation of chromosome number in M. mandarinus.

Establishment of a human malignant T lymphoma cell line carrying retrovirus-like particles with RT activity

We have established an IL-2 independent malignant lymphoma line (CM-1) from peripheral T lymphocytes donated by a female patient with nervous system disease, the biological characteristics of CM-1 cells was studied in this paper. Another T lymphocytes, such as peripheral T lymphocytes donated by a male patient with multiple sclerosis, could be transformed into a malignant lymphoma line by using filtered supernatant of the CM-1 cultured medium, thus the CM-2 cell line was established. The CM-1 and CM-2 cells were transplanted by subcutaneous inoculation into nude mice, and could cause the occurrence of typical malignant lymphoma. The observation of electron micrographs suggested the existence of virions in the CM-1 and CM-2 cells, and these virions were similar to retrovirus in the ultra-structure characteristics. It was found that this virus possesses reverse transcriptase activity. Results obtained from serological assay, molecular hybridization and PCR excluded the existence of other human viruses, which were commonly used in our laboratory. The unknown virus possesses strong transformation activity, and probably is a new retrovirus. Meanwhile, the work on the clone and sequence analysis of this virus are being carried out.