A short gamma-ray burst apparently associated with an elliptical galaxy at redshift z = 0.225

Gamma-ray bursts (GRBs) come in two classes: long (> 2 s), soft-spectrum bursts and short, hard events. Most progress has been made on understanding the long GRBs, which are typically observed at high redshift (z approximately 1) and found in subluminous star-forming host galaxies. They are likely to be produced in core-collapse explosions of massive stars. In contrast, no short GRB had been accurately (< 10') and rapidly (minutes) located. Here we report the detection of the X-ray afterglow from--and the localization of--the short burst GRB 050509B. Its position on the sky is near a luminous, non-star-forming elliptical galaxy at a redshift of 0.225, which is the location one would expect if the origin of this GRB is through the merger of neutron-star or black-hole binaries. The X-ray afterglow was weak and faded below the detection limit within a few hours; no optical afterglow was detected to stringent limits, explaining the past difficulty in localizing short GRBs.     

Antitumor activity of the Isodon diterpenoids: structural requirements for the activity.

A significant antitumor activity of oridonin (1) and lasiokaurin (2), the kaurene-type diterpenoids of Isodon species, was shown by their i.p. injection to the test mice inoculated by Ehrlich ascites carcinoma. Enmein (8), compounds 9 and 3 were also active under larger dose. Subsequently, the relationship between their chemical structure and antitumor activity was investigated, and the activity of oridonin (1) and lasiokaurin (2) was rationalized in terms of their structural feature.     

Antitumor activity of the isodon diterpenoids: Structural requirements for the activity

Summary A significant antitumor activity of oridonin (1) and lasiokaurin (2), the kaurene-type diterpenoids ofIsodon species, was shown by their i.p. injection to the test mice inoculated by Ehrlich ascites carcinoma. Enmein (8), compounds9 and3 were also active under larger dose. Subsequently, the relationship between their chemical structure and antitumor activity was investigated, and the activity of oridonin (1) and lasiokaurin (2) was rationalized in terms of their structural feature.     

Contraction of the large conductance coronary artery produced by acetylcholine in the mini pig

Summary In the mini pig, acetylcholine reduced the coronary blood flow and constricted the large coronary artery. These effects were abolished by atropine, but not by phentolamine, suggesting that cholinergic mechanisms may be involved in coronary artery vasoconstriction.     

Northern Hemisphere forcing of climatic cycles in Antarctica over the past 360,000 years

The Milankovitch theory of climate change proposes that glacial-interglacial cycles are driven by changes in summer insolation at high northern latitudes. The timing of climate change in the Southern Hemisphere at glacial-interglacial transitions (which are known as terminations) relative to variations in summer insolation in the Northern Hemisphere is an important test of this hypothesis. So far, it has only been possible to apply this test to the most recent termination, because the dating uncertainty associated with older terminations is too large to allow phase relationships to be determined. Here we present a new chronology of Antarctic climate change over the past 360,000 years that is based on the ratio of oxygen to nitrogen molecules in air trapped in the Dome Fuji and Vostok ice cores. This ratio is a proxy for local summer insolation, and thus allows the chronology to be constructed by orbital tuning without the need to assume a lag between a climate record and an orbital parameter. The accuracy of the chronology allows us to examine the phase relationships between climate records from the ice cores and changes in insolation. Our results indicate that orbital-scale Antarctic climate change lags Northern Hemisphere insolation by a few millennia, and that the increases in Antarctic temperature and atmospheric carbon dioxide concentration during the last four terminations occurred within the rising phase of Northern Hemisphere summer insolation. These results support the Milankovitch theory that Northern Hemisphere summer insolation triggered the last four deglaciations.     

HLA BW54 and B5 in Japanese diabetics with juvenile-onset and insulin-dependency (with special reference to the family history)

Summary The frequency of HLA BW54 and B5 in Japanese patients with JOD is increased and decreased, respectively. In JOD patients without a family history of MOD, the frequency of BW54 is significantly increased, whereas in JOD patients with a positive family history the frequency was not increased in a statistically significant manner.     

A direct link of the Mos-MAPK pathway to Erp1/Emi2 in meiotic arrest of Xenopus laevis eggs

In vertebrates, unfertilized eggs (or mature oocytes) are arrested at metaphase of meiosis II by a cytoplasmic activity called cytostatic factor (CSF). The classical Mos-MAPK pathway has long been implicated in CSF arrest of vertebrate eggs, but exactly how it exerts CSF activity remains unclear. Recently, Erp1 (also called Emi2), an inhibitor of the anaphase-promoting complex/cyclosome (APC/C) required for degradation of the mitotic regulator cyclin B (ref. 5), has also been shown to be a component of CSF in both Xenopus and mice. Erp1 is destroyed on fertilization or egg activation, like Mos. However, despite these similarities the Mos-MAPK (mitogen-activated protein kinase) pathway and Erp1 are thought to act rather independently in CSF arrest. Here, we show that p90rsk, the kinase immediately downstream from Mos-MAPK, directly targets Erp1 for CSF arrest in Xenopus oocytes. Erp1 is synthesized immediately after meiosis I, and the Mos-MAPK pathway or p90rsk is essential for CSF arrest by Erp1. p90rsk can directly phosphorylate Erp1 on Ser 335/Thr 336 both in vivo and in vitro, and upregulates both Erp1 stability and activity. Erp1 is also present in early embryos, but has little CSF activity owing, at least in part, to the absence of p90rsk activity. These results clarify the direct link of the classical Mos-MAPK pathway to Erp1 in meiotic arrest of vertebrate oocytes.