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961.
962.
The localization of sialoglycosphingolipids in the plasma membrane of sea urchin spermatozoa was studied by employing immunological methods including immunolysis of liposomal model membranes. The antibodies produced against these complex lipids were found to agglutinate various sea urchin spermatozoa differently. Both species differences and species similarities in the agglutination were found in spermatozoa of the echinoderm, the sea urchin and the starfish. The agglutination of the sea urchin spermatozoa was inhibited specifically by ceratain carbohydrates. Only a limited number of molecular species of sialoglycosphingolipid were localized at the surface of the plasma membrane of sea urchin spermatozoa cells. Moreover, topographical differences were found in the localization of the sialoglycosphingolipids at the cell surface of spermatozoa. 相似文献
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965.
Toshikazu Shioiri Masashi Muroi Fumihiko Hatao Masato Nishida Toshihisa Ogawa Yoshikazu Mimura Yasuyuki Seto Michio Kaminishi Ken-ichi Tanamoto 《生物化学与生物物理学报:疾病的分子基础》2009,1792(10):1011-1018
Endothelial cell injury/dysfunction is considered to play a critical role in the pathogenesis of severe sepsis and septic shock. Although it is considered that endothelial cell apoptosis is involved in endothelial injury/dysfunction, physiological involvement remains ambiguous since the induction of apoptosis requires the inhibition of endogenous apoptosis inhibitors. Here we show that caspase-3 activation, a biological indicator of apoptosis, is observed in response to lipopolysaccharide (LPS) stimulation even under the influence of endogenous apoptosis inhibitors, and that activated caspase-3 is rapidly released from human umbilical vein endothelial cells (HUVEC). In the presence of cycloheximide (CHX), an increase in intracellular caspase-3/7 activity in response to LPS was not detected in HUVEC up to 24 h following stimulation even in the presence of LPS-binding protein (LBP), soluble CD14 and soluble MD-2, whereas the decrease in cell viability and increase in release of the cellular enzyme lactate dehydrogenase (LDH) were observed in a soluble CD14/LBP-dependent manner. On the other hand, even in the absence of CHX, a significant increase in caspase-3/7 activity and a cleaved caspase-3 fragment with a slight increase in LDH release was observed in culture supernatants in response to LPS. This increase in caspase-3/7 activity was observed even when LDH release was undetected. These results indicate that caspase-3 is activated by LPS under physiological conditions and suggest that HUVEC escape from cell death by rapidly releasing activated caspase-3 into extracellular space. Failure of this escape mechanism may result in endothelial injury/dysfunction. 相似文献
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Yuko Osawa Kazunori Ikebukuro Takenori Kumagai Hiroaki Motoki Takafumi Matsuo Michio Horiuchi Koji Sode 《Biotechnology letters》2009,31(5):735-733
We have detected PCR products from Salmonella spp. and Influenza A virus using Zn finger protein Zif268 and Sp1, respectively. Previously, we demonstrated a novel method
of rapid and specific detection of PCR products from Legionella pneumophila genome using Zn finger protein Sp1. In principle, this methodology might be applied to the detection of most bacteria and
viruses using various Zn finger proteins. Here, to demonstrate the wider applicability of our method, we detected PCR products
from Salmonella spp. and the Influenza A virus. BLAST data indicated the Zif268 and Sp1 recognition sequence were located on the gyrB gene of Salmonella spp. and the nucleoprotein gene of Influenza A virus, respectively. The PCR products from the oligonucleotide corresponding
to the gyrB gene of Salmonella spp. or the nucleoprotein gene of the Influenza A virus could be specifically detected by ELISA or fluorescence depolarization
measurement using Zif268 or Sp1. These results indicate the wide applicability of our novel methodology.
An erratum to this article can be found at 相似文献
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970.
Invasive alien species (IAS) pose serious threats to native ecosystems worldwide. In some regions, laws and/or lists related to alien species have been made, but their effects on actual measures against alien species have been little studied. In Japan the IAS act, which came into force in 2005, lists many harmful species under the heading “Designated IAS”. The importation, domestication, sale or release of these species is tightly regulated. In addition, other species are named as alerted alien species (AASs) on the “alien species alert list” to raise public awareness. In this paper we examined the situation in Japan as case study that is exposed to threats from alien species under such laws in recent year to evaluate the effects of that for public interesting. We conducted a survey of the effects of the legal designation and other classification of alien plant species, examining a number of aspects, including research publications, eradications and public awareness. In our analysis, the degree of harmfulness of IASs was considered on the basis of weed risk assessment (WRA). The results show that legal classification of IASs has led to increases in research focused on the designated species, eradication efforts and public awareness. Similar results were also apparent for some AASs, but there was a great deal of variability among the many sub-categories of AASs. This may be partly because AAS sub-categories are based on different premises, and partly because the identification of AASs is not necessarily linked to legal controls that affect the behavior of individuals. 相似文献