2008/04/27
JOHOR BARU: Sixteen people in Kampung Ulu Choh here have been diagnosed with chikungunya, a non-lethal viral fever with symptoms similar to dengue. .....
http://www.nst.com.my/Current_News/NST/Sunday/National/2224874/Article/index_html
2008年4月29日 星期二
2008年4月28日 星期一
Insects use plant like a telephone
Dutch ecologist Roxina Soler and her colleagues have discovered that subterranean and aboveground herbivorous insects can communicate with each other by using plants as telephones. Subterranean insects issue chemical warning signals via the leaves of the plant. This way, aboveground insects are alerted that the plant is already ‘occupied’........
http://www.nwo.nl/nwohome.nsf/pages/NWOA_7DLG9H_Eng?Opendocument
Larvicidal activity of tectoquinone isolated from red heartwood-type Cryptomeria japonica (柳杉) against two mosquito species
Bioresource Technology 99 (2008) 3617–3622
Sen-Sung Cheng a, Chin-Gi Huang b, Wei-June Chen c, Yueh-Hsiung Kuo d,Shang-Tzen Chang e,*
Abstract
Mosquito larvicidal activities of methanolic extracts from different plant parts of red heartwood-type Cryptomeria japonica D. Don against the fourth-instar larvae of Aedes aegypti and Aedes albopictus were examined. Results of mosquito larvicidal tests demonstrated that the n-hexane fraction of C. japonica sapwood methanolic extract had an excellent inhibitory effect against the larvae of A. aegypti and A. albopictus and its LC50 values were 2.4 and 3.3 μg/ml, respectively, in 24 h. Following the bioactivity-guided fractionation procedure, the active constituent isolated from C. japonica sapwood was characterized as tectoquinone by spectroscopic analyses. The LC50 values of tectoquinone against A. aegypti and A. albopictus in 24 h were 3.3 and 5.4 μg/ml, respectively. In addition, comparisons of mosquito larvicidal activity of anthraquinone congeners demonstrated that anthraquinone skeleton with a methyl group at C-2 position, such as tectoquinone, exhibited the strongest mosquito larvicidal activity. Results of this study show that the methanolic extract of C. japonica sapwood may be considered as a potent source and tectoquinone as a new natural mosquito larvicidal agent.
Keywords: Cryptomeria japonica; Aedes aegypti; Aedes albopictus; Tectoquinone; Mosquito larvicidal activity
Sen-Sung Cheng a, Chin-Gi Huang b, Wei-June Chen c, Yueh-Hsiung Kuo d,Shang-Tzen Chang e,*
Abstract
Mosquito larvicidal activities of methanolic extracts from different plant parts of red heartwood-type Cryptomeria japonica D. Don against the fourth-instar larvae of Aedes aegypti and Aedes albopictus were examined. Results of mosquito larvicidal tests demonstrated that the n-hexane fraction of C. japonica sapwood methanolic extract had an excellent inhibitory effect against the larvae of A. aegypti and A. albopictus and its LC50 values were 2.4 and 3.3 μg/ml, respectively, in 24 h. Following the bioactivity-guided fractionation procedure, the active constituent isolated from C. japonica sapwood was characterized as tectoquinone by spectroscopic analyses. The LC50 values of tectoquinone against A. aegypti and A. albopictus in 24 h were 3.3 and 5.4 μg/ml, respectively. In addition, comparisons of mosquito larvicidal activity of anthraquinone congeners demonstrated that anthraquinone skeleton with a methyl group at C-2 position, such as tectoquinone, exhibited the strongest mosquito larvicidal activity. Results of this study show that the methanolic extract of C. japonica sapwood may be considered as a potent source and tectoquinone as a new natural mosquito larvicidal agent.
Keywords: Cryptomeria japonica; Aedes aegypti; Aedes albopictus; Tectoquinone; Mosquito larvicidal activity
2008年4月26日 星期六
Use of a commercial enzyme immunoassay to monitor dengue virus replication
http://www.virologyj.com/content/5/1/51
Abstract (provisional)
Current methods for dengue virus quantitation are either time consuming, technically demanding or costly. As an alternative, the commercial enzyme immunoassay PlateliaTM Dengue NS1 AG (Bio-Rad Laboratories) was used to monitor semiquantitatively dengue virus replication in cultured cells. The presence of NS1 protein was evaluated in supernatants from Vero and C6/36 cells infected with dengue virus. The amount of NS1 detected in the supernatants of infected cells was proportional to the initial MOI used and to the time of post infection harvest. This immunoassay was also able to detect the presence of NS1 in the supernatants of infected human macrophages. Inhibition of dengue virus replication in C6/36 cells treated with lysosomotropic drugs was readily monitored with the use of this assay. These results suggest that the PlateliaTM Dengue NS1 AG kit can be used as a fast and reliable surrogate method for the relative quantitation of dengue virus replication in cultured cells.
Abstract (provisional)
Current methods for dengue virus quantitation are either time consuming, technically demanding or costly. As an alternative, the commercial enzyme immunoassay PlateliaTM Dengue NS1 AG (Bio-Rad Laboratories) was used to monitor semiquantitatively dengue virus replication in cultured cells. The presence of NS1 protein was evaluated in supernatants from Vero and C6/36 cells infected with dengue virus. The amount of NS1 detected in the supernatants of infected cells was proportional to the initial MOI used and to the time of post infection harvest. This immunoassay was also able to detect the presence of NS1 in the supernatants of infected human macrophages. Inhibition of dengue virus replication in C6/36 cells treated with lysosomotropic drugs was readily monitored with the use of this assay. These results suggest that the PlateliaTM Dengue NS1 AG kit can be used as a fast and reliable surrogate method for the relative quantitation of dengue virus replication in cultured cells.
2008年4月24日 星期四
2008年4月22日 星期二
Herpes virus morphogenesis
After leaving the nucleus by a budding-fusion mechanism, nucleocapsids gain their final tegument and envelope in the cytoplasm by budding into trans-Golgi network vesicles. These are then transported to the plasma membrane, where vesicle and plasma membrane fuse and virions are released from the cell.
(繼續閱讀)....
(繼續閱讀)....
The role of lipid rafts in HIV-1 replication
For reading only~~~
Advances in cell biology revealed that the plasma membrane is not a homogenous sea of lipid, but consists of various types of microdomains with specific sets of protein and lipid components. One such microdomain is the cholesterol-rich lipid raft. Rafts facilitate various cellular functions, such as signal transduction and protein trafficking, often by providing concentration platforms for promoting protein-protein interactions. A top priority of our research is to fully understand the roles that rafts play throughout the replication cycle of HIV-1 and other retroviruses.
HIV-1 Gag, the major building block of virus particles, has been identified as a raft-associated protein. Moreover, raft disruption severely impairs HIV-1 virus particle production and infectivity of released progeny virions. These findings suggest that rafts play important role(s) in both virus assembly and particle infectivity. We are currently identifying the steps in the assembly/release pathway at which rafts are involved. Future studies will be aimed at determining the molecular mechanisms by which rafts promote virus assembly as well as the nature of the raft subsets involved in infectious virus particle production.
Virus transmission at the interface between two cells is a markedly more efficient mechanism of virus spread than cell-free transmission and likely represents the major mode of transmission for HIV-1 in infected individuals. However, the mechanism of cell-to-cell transmission has not been well studied. Interestingly, we observed that, when a producer cell contacts a target cell, lipid rafts and Gag colocalize at the cell-cell contact interface (see Fig. 1). These results suggest that lipid rafts play a key role in cell-to-cell HIV-1 transmission. The laboratory will further characterize raft-rich contact structures and examine their role(s) in virus spread.
~~~~cited from materials of Ono Lab, University of Michigan Medical School
http://sitemaker.umich.edu/ono.lab/lipid_rafts_and_hiv-1_replication
Advances in cell biology revealed that the plasma membrane is not a homogenous sea of lipid, but consists of various types of microdomains with specific sets of protein and lipid components. One such microdomain is the cholesterol-rich lipid raft. Rafts facilitate various cellular functions, such as signal transduction and protein trafficking, often by providing concentration platforms for promoting protein-protein interactions. A top priority of our research is to fully understand the roles that rafts play throughout the replication cycle of HIV-1 and other retroviruses.HIV-1 Gag, the major building block of virus particles, has been identified as a raft-associated protein. Moreover, raft disruption severely impairs HIV-1 virus particle production and infectivity of released progeny virions. These findings suggest that rafts play important role(s) in both virus assembly and particle infectivity. We are currently identifying the steps in the assembly/release pathway at which rafts are involved. Future studies will be aimed at determining the molecular mechanisms by which rafts promote virus assembly as well as the nature of the raft subsets involved in infectious virus particle production.
Virus transmission at the interface between two cells is a markedly more efficient mechanism of virus spread than cell-free transmission and likely represents the major mode of transmission for HIV-1 in infected individuals. However, the mechanism of cell-to-cell transmission has not been well studied. Interestingly, we observed that, when a producer cell contacts a target cell, lipid rafts and Gag colocalize at the cell-cell contact interface (see Fig. 1). These results suggest that lipid rafts play a key role in cell-to-cell HIV-1 transmission. The laboratory will further characterize raft-rich contact structures and examine their role(s) in virus spread.
~~~~cited from materials of Ono Lab, University of Michigan Medical School
http://sitemaker.umich.edu/ono.lab/lipid_rafts_and_hiv-1_replication
北市近三千外勞有寄生蟲
有那麼嚴重嗎！ 人體試驗最佳對象！ 買些血，做陽性血清實驗...
一、 北市近三千外勞 有寄生蟲 (蘋果 大台北社區新聞A14)
二、 外勞健康問題 寄生蟲最嚴重 (自由 台北焦點A11)
三、 外勞健檢不合格 寄生蟲惹禍 (中時 北市新聞C2)
四、 北市外勞8.76%體檢不合格 (新生 要聞2)
五、 染肺結核 去年30外勞遣送出境 (民眾 北市新聞14)
六、 北市外勞健檢 8.76%不合格 (中華 醫藥資訊C2)
七、 衛生習慣好 可降低寄生蟲感染 (中華 醫藥資訊C2)
八、 Nine percent of foreign workers fail health check (Taipei Times台灣新聞2)
一、 北市近三千外勞 有寄生蟲 (蘋果 大台北社區新聞A14)
二、 外勞健康問題 寄生蟲最嚴重 (自由 台北焦點A11)
三、 外勞健檢不合格 寄生蟲惹禍 (中時 北市新聞C2)
四、 北市外勞8.76%體檢不合格 (新生 要聞2)
五、 染肺結核 去年30外勞遣送出境 (民眾 北市新聞14)
六、 北市外勞健檢 8.76%不合格 (中華 醫藥資訊C2)
七、 衛生習慣好 可降低寄生蟲感染 (中華 醫藥資訊C2)
八、 Nine percent of foreign workers fail health check (Taipei Times台灣新聞2)
長庚醫護宿舍 傳疑似登革熱病例
http://www.libertytimes.com.tw/2008/new/apr/22/today-south4.htm
〔記者方志賢／鳥松報導〕高雄長庚醫護人員宿舍傳出疑似登革熱疫情，一名牙醫因發燒、紅疹就醫，經通報疑似登革熱病例，雖第一次採血檢驗呈現陰性，仍須二次採血才能確定，高縣衛生局已緊急派員到宿舍噴藥消毒及清除病媒蚊孳生源。
該名牙醫住在醫院醫護人員宿舍，............
〔記者方志賢／鳥松報導〕高雄長庚醫護人員宿舍傳出疑似登革熱疫情，一名牙醫因發燒、紅疹就醫，經通報疑似登革熱病例，雖第一次採血檢驗呈現陰性，仍須二次採血才能確定，高縣衛生局已緊急派員到宿舍噴藥消毒及清除病媒蚊孳生源。
該名牙醫住在醫院醫護人員宿舍，............
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