转基因生物对我们来说是好的么——人类学家对这场争论的贡献

转基因生物是有望带来巨大益处的新的生物体,同时也会带来诸多风险。人类学能够在看待转基因农作物和食品问题上提供重要的批判视角。为了对有关转基因生物的问题给出令人信服的回答,区分公共转基因生物和公司转基因生物十分必要,并且还必须坚持关注新技术的社会维度和政治维度。     

Artemisinins target the SERCA of Plasmodium falciparum

Artemisinins are extracted from sweet wormwood (Artemisia annua) and are the most potent antimalarials available, rapidly killing all asexual stages of Plasmodium falciparum. Artemisinins are sesquiterpene lactones widely used to treat multidrug-resistant malaria, a disease that annually claims 1 million lives. Despite extensive clinical and laboratory experience their molecular target is not yet identified. Activated artemisinins form adducts with a variety of biological macromolecules, including haem, translationally controlled tumour protein (TCTP) and other higher-molecular-weight proteins. Here we show that artemisinins, but not quinine or chloroquine, inhibit the SERCA orthologue (PfATP6) of Plasmodium falciparum in Xenopus oocytes with similar potency to thapsigargin (another sesquiterpene lactone and highly specific SERCA inhibitor). As predicted, thapsigargin also antagonizes the parasiticidal activity of artemisinin. Desoxyartemisinin lacks an endoperoxide bridge and is ineffective both as an inhibitor of PfATP6 and as an antimalarial. Chelation of iron by desferrioxamine abrogates the antiparasitic activity of artemisinins and correspondingly attenuates inhibition of PfATP6. Imaging of parasites with BODIPY-thapsigargin labels the cytosolic compartment and is competed by artemisinin. Fluorescent artemisinin labels parasites similarly and irreversibly in an Fe2+-dependent manner. These data provide compelling evidence that artemisinins act by inhibiting PfATP6 outside the food vacuole after activation by iron.     

GC/MS法追踪摇头丸杂质体系

本文运用GS/MS的总离子流法,选择离子法,对南京地区常见的几种摇头丸进行全面分析,找出与合成途径相关的痕量杂质,根据杂质情况初步确定其合成途径.     

Oxygen consumption of genetically obese rats

Zusammenfassung Der Sauerstoffverbrauch genetisch fettleibiger Ratten ist auffallend niedriger als derjenige von Normalratten (littermates), die nach Hypothalamusverletzung fettleibig wurden.

---

---

J.Mayer, R. E.Russell, M. W.Bates and M. M.Dickie, Endocrinology56, 318 (1952).

---

The author thanks Dr. E. B.Astwood for his continuing support and encouragement.