Hepatitis B virus (HBV) infection constitutes a serious global health problem. In countries with intermediate or high endemicity for HBV, exacerbations of chronic hepatitis B may be the first presentation of HBV infec...Hepatitis B virus (HBV) infection constitutes a serious global health problem. In countries with intermediate or high endemicity for HBV, exacerbations of chronic hepatitis B may be the first presentation of HBV infection. Some of these patients may be diagnosed mistakenly as having acute hepatitis B. Accurate diagnosis in these cases is very important for deciding whether to start treatment or not, because acute hepatitis B does not require therapy, while exacerbation of chronic hepatitis may benefit from it. Clinical and routine laboratory findings cannot help distinguishing between these two conditions. Therefore, several assays have been proposed for this purpose during the last few years. The presence of high levels of anti-HBe antibodies, HBsAg and HBV DNA are typical of chronic disease, whereas high titers of IgM anti-HBc, together with their high avidity index, characterize acute HBV infection. Starting from the description of a patient with acute hepatitis B-who recently came to our observation-we critically review the currently available assays that may help distinguishing between the different conditions and lead to the optimal management of each patient.展开更多
Karenia is one of the most harmful and representative red tide genus in a temperate zone. Blooms caused by this genus have resulted in massive fish death in the South China Sea and the East China Sea. However, the pot...Karenia is one of the most harmful and representative red tide genus in a temperate zone. Blooms caused by this genus have resulted in massive fish death in the South China Sea and the East China Sea. However, the potential effects of this dinoflagellate on human health through the transfer of toxins via marine food webs, and the mechanisms of toxicity, are still unknown. Therefore, we examined the toxic effects of a strain of K. mikimotoi (isolated from the South China Sea) on the proliferation and morphology of four mammalian cell lines (two normal cell lines and two cancer cell lines). In addition, we carried out a preliminary investigation on the mechanism of toxicity of the alga. The results show that the polar lipid-soluble component ofK. mikimotoi significantly inhibited proliferation of the four cell lines, and resulted in the ceils becoming spherical, swollen and damaged. The result of Annexin V and PI double-staining confirmed that cell membranes were disrupted. The malonaldehyde (MDA) contents in the medium of the four cell lines treated with the polar-lipid extracts all increased significantly, which indicates that the polar-lipid toxins produced by K. rnikimotoi could adversely affect mammalian cells by inducing lipid peroxidation. We conclude that K. mikimotoi is a potential threat to human health, and the comprehensive effect of this dinoflagellate and its mechanisms should be investigated further.展开更多
Objectives: To describe and analyze HIV/AIDS/STD-related high risk behaviors and affecting factors of men who have sex with men (MSM) in China's Mainland~ Methods: 426 self-administered or interview-based question...Objectives: To describe and analyze HIV/AIDS/STD-related high risk behaviors and affecting factors of men who have sex with men (MSM) in China's Mainland~ Methods: 426 self-administered or interview-based questionnaires collected from MSM were analyzed with SPSS or SAS Systems. Results: Of the MSM, four-fifths had engaged in oral-genital intercourse, about half had engaged in anal intercourse, and in the past year more than two-fifths had casual sexual partner(s).Very few maintained monogamous sexual relationships, and nearly half also had intercourse with women. One fourth had previously been diagnosed with a venereal diseases. One HIV+individual was found among the 40 who reported having been tested for HIV. Only two men consistently used condoms among the one-third who had ever used condoms, despite almost universal knowledge of HIV and its transmission. Conclusions: MSM in China's Mainland are very sexually active, highlighting the possibility of a serious HIV epidemic that may be directly spread to the female population. However,AIDS interventions targeting MSM face severe obstructions resulting from cultural bias and other factors.展开更多
A total of 100 H1N1 flu real-time-PCR positive throat swabs collected from fever patients in Zhejiang, Hubei and Guangdong between June and November 2009, were provided by local CDC laboratories. After MDCK cell cultu...A total of 100 H1N1 flu real-time-PCR positive throat swabs collected from fever patients in Zhejiang, Hubei and Guangdong between June and November 2009, were provided by local CDC laboratories. After MDCK cell culture, 57 Influenza A Pandemic (H1N1) viruses were isolated and submitted for whole genome sequencing. A total of 39 HA sequences, 52 NA sequences, 36 PB2 sequences, 31 PB1 sequences, 40 PA sequences, 48 NP sequences, 51 MP sequences and 36 NS sequences were obtained, including 20 whole genome sequences. Sequence comparison revealed they shared a high degree of homology (96%-99%) with known epidemic strains (A/Califomia/04/2009(H1N1). Phylogenetic analysis showed that although the sequences were highly conserved, they clustered into a small number of groups with only a few distinct strains. Site analysis revealed three substitutions at loop 220 (221-228) of the HA receptor binding site in the 39 HA sequences: A/Hubei/86/2009 PKVRDQEG→PKVRDQEA, A/Zhejiang/08/2009 PKVRDQEG→PKVRDQER, A/Hubei/75/2009 PKVRDQEG→PKVRDQGG, the A/Hubei/75/2009 was isolated from an acute case, while the other two were from patients with mild symptoms. Other key sites such as 119, 274, 292 and 294 amino acids of NA protein,627 of PB2 protein were conserved. Meanwhile, all the M2 protein sequences possessed the Ser32Asn mutation, suggesting that these viruses were resistant to adamantanes. Comparison of these sequences with other H1N1 viruses collected from the NCBI database provides insight into H1N1 transmission and circulation patterns.展开更多
Objective: To explore the effect of cellular immunity in halothane hepatitis. Methods: Hepatotoxicity model was established by exposing male Hartley guinea pigs to 1% halothane via inspiration for 4 h each time for 1 ...Objective: To explore the effect of cellular immunity in halothane hepatitis. Methods: Hepatotoxicity model was established by exposing male Hartley guinea pigs to 1% halothane via inspiration for 4 h each time for 1 or 3 times within a 42-day interval. Then their hepatocytes and lymphocytes were collected and divided into 2 parts for different cultures. Hepatocytes were cultivated with or without 1% halothane for 4 h and lymphocytes were cultivated with or without 12.5 μg/ml trifluoroacetylated guinea pig serum albumin (TFA-GSA). Then the 2 kinds of hepatocytes were co-cultivated with lymphocytes (1:100) with or without TFA-GSA induction respectively and the supernatant fluid was taken after 24, 48 and 72 h to determine the concentration of alanine aminotransferase (ALT). The halothane cultivated hepatocytes were co-cultivated with various proportion of TFA-GSA antigen induced lymphocytes and ALT was determined after 48 h to determine the proper proportion of hepatocytes and lymphocyte. Results: Lymphocytes of 3 times halothane induced guinea pigs caused a significant increase of ALT in hepatocytes with or without halothane induction. But the lymphocytes of 1 time halothane induced guinea pigs only caused a significant increase of ALT in hepatocytes with induction of halothane. The increase of ALT was only seen after 48- and 72-hour co-culture. The proper proportion of hepatocytes and lymphocytes was 1:100 for lymphocytes cytotoxicity. Conclusion: Lymphocytes is sensitized after inhalation of halothane and generates cytotoxicity to hepatocytes. The immune response of lymphocytes to hepatocytes will be enhanced by repeated inhalation of halothane. The cellular immunity may be one of the mechanisms of halothane induced hepatotoxicity.展开更多
文摘Hepatitis B virus (HBV) infection constitutes a serious global health problem. In countries with intermediate or high endemicity for HBV, exacerbations of chronic hepatitis B may be the first presentation of HBV infection. Some of these patients may be diagnosed mistakenly as having acute hepatitis B. Accurate diagnosis in these cases is very important for deciding whether to start treatment or not, because acute hepatitis B does not require therapy, while exacerbation of chronic hepatitis may benefit from it. Clinical and routine laboratory findings cannot help distinguishing between these two conditions. Therefore, several assays have been proposed for this purpose during the last few years. The presence of high levels of anti-HBe antibodies, HBsAg and HBV DNA are typical of chronic disease, whereas high titers of IgM anti-HBc, together with their high avidity index, characterize acute HBV infection. Starting from the description of a patient with acute hepatitis B-who recently came to our observation-we critically review the currently available assays that may help distinguishing between the different conditions and lead to the optimal management of each patient.
基金Supported by the National Basic Research Program of China (973 Program) (No. 2010CB428700)the National Natural Science Foundation of China (Nos. U0733006, 40821004)the Knowledge Innovation Program of the Chinese Academy of Sciences (No. KZCX2-YW-Q07-02)
文摘Karenia is one of the most harmful and representative red tide genus in a temperate zone. Blooms caused by this genus have resulted in massive fish death in the South China Sea and the East China Sea. However, the potential effects of this dinoflagellate on human health through the transfer of toxins via marine food webs, and the mechanisms of toxicity, are still unknown. Therefore, we examined the toxic effects of a strain of K. mikimotoi (isolated from the South China Sea) on the proliferation and morphology of four mammalian cell lines (two normal cell lines and two cancer cell lines). In addition, we carried out a preliminary investigation on the mechanism of toxicity of the alga. The results show that the polar lipid-soluble component ofK. mikimotoi significantly inhibited proliferation of the four cell lines, and resulted in the ceils becoming spherical, swollen and damaged. The result of Annexin V and PI double-staining confirmed that cell membranes were disrupted. The malonaldehyde (MDA) contents in the medium of the four cell lines treated with the polar-lipid extracts all increased significantly, which indicates that the polar-lipid toxins produced by K. rnikimotoi could adversely affect mammalian cells by inducing lipid peroxidation. We conclude that K. mikimotoi is a potential threat to human health, and the comprehensive effect of this dinoflagellate and its mechanisms should be investigated further.
文摘Objectives: To describe and analyze HIV/AIDS/STD-related high risk behaviors and affecting factors of men who have sex with men (MSM) in China's Mainland~ Methods: 426 self-administered or interview-based questionnaires collected from MSM were analyzed with SPSS or SAS Systems. Results: Of the MSM, four-fifths had engaged in oral-genital intercourse, about half had engaged in anal intercourse, and in the past year more than two-fifths had casual sexual partner(s).Very few maintained monogamous sexual relationships, and nearly half also had intercourse with women. One fourth had previously been diagnosed with a venereal diseases. One HIV+individual was found among the 40 who reported having been tested for HIV. Only two men consistently used condoms among the one-third who had ever used condoms, despite almost universal knowledge of HIV and its transmission. Conclusions: MSM in China's Mainland are very sexually active, highlighting the possibility of a serious HIV epidemic that may be directly spread to the female population. However,AIDS interventions targeting MSM face severe obstructions resulting from cultural bias and other factors.
基金The Ministry of Science and Technology of China (2010CB534005,2007FY210700, 2009ZX10004109)the National Natural Science Foundation of China (30970024,30900060)+2 种基金The National R&D Infrastructure and Facility Development Program of China under Grant No. BSDN2009-10 &18The Chinese Academy of Sciences (KSCX2-YW- N-065, KSCX2-YW-R-157, 158 and 159 INFO-115-C01-SDB3-01, INFO-115-C01-SDB4-21, IN-FO-115-D02, IN-FO- 115-C01-SDB2-02)
文摘A total of 100 H1N1 flu real-time-PCR positive throat swabs collected from fever patients in Zhejiang, Hubei and Guangdong between June and November 2009, were provided by local CDC laboratories. After MDCK cell culture, 57 Influenza A Pandemic (H1N1) viruses were isolated and submitted for whole genome sequencing. A total of 39 HA sequences, 52 NA sequences, 36 PB2 sequences, 31 PB1 sequences, 40 PA sequences, 48 NP sequences, 51 MP sequences and 36 NS sequences were obtained, including 20 whole genome sequences. Sequence comparison revealed they shared a high degree of homology (96%-99%) with known epidemic strains (A/Califomia/04/2009(H1N1). Phylogenetic analysis showed that although the sequences were highly conserved, they clustered into a small number of groups with only a few distinct strains. Site analysis revealed three substitutions at loop 220 (221-228) of the HA receptor binding site in the 39 HA sequences: A/Hubei/86/2009 PKVRDQEG→PKVRDQEA, A/Zhejiang/08/2009 PKVRDQEG→PKVRDQER, A/Hubei/75/2009 PKVRDQEG→PKVRDQGG, the A/Hubei/75/2009 was isolated from an acute case, while the other two were from patients with mild symptoms. Other key sites such as 119, 274, 292 and 294 amino acids of NA protein,627 of PB2 protein were conserved. Meanwhile, all the M2 protein sequences possessed the Ser32Asn mutation, suggesting that these viruses were resistant to adamantanes. Comparison of these sequences with other H1N1 viruses collected from the NCBI database provides insight into H1N1 transmission and circulation patterns.
基金the National Natural Science Foundation of China (39900140)
文摘Objective: To explore the effect of cellular immunity in halothane hepatitis. Methods: Hepatotoxicity model was established by exposing male Hartley guinea pigs to 1% halothane via inspiration for 4 h each time for 1 or 3 times within a 42-day interval. Then their hepatocytes and lymphocytes were collected and divided into 2 parts for different cultures. Hepatocytes were cultivated with or without 1% halothane for 4 h and lymphocytes were cultivated with or without 12.5 μg/ml trifluoroacetylated guinea pig serum albumin (TFA-GSA). Then the 2 kinds of hepatocytes were co-cultivated with lymphocytes (1:100) with or without TFA-GSA induction respectively and the supernatant fluid was taken after 24, 48 and 72 h to determine the concentration of alanine aminotransferase (ALT). The halothane cultivated hepatocytes were co-cultivated with various proportion of TFA-GSA antigen induced lymphocytes and ALT was determined after 48 h to determine the proper proportion of hepatocytes and lymphocyte. Results: Lymphocytes of 3 times halothane induced guinea pigs caused a significant increase of ALT in hepatocytes with or without halothane induction. But the lymphocytes of 1 time halothane induced guinea pigs only caused a significant increase of ALT in hepatocytes with induction of halothane. The increase of ALT was only seen after 48- and 72-hour co-culture. The proper proportion of hepatocytes and lymphocytes was 1:100 for lymphocytes cytotoxicity. Conclusion: Lymphocytes is sensitized after inhalation of halothane and generates cytotoxicity to hepatocytes. The immune response of lymphocytes to hepatocytes will be enhanced by repeated inhalation of halothane. The cellular immunity may be one of the mechanisms of halothane induced hepatotoxicity.