A sea-floor spreading event captured by seismometers     

Tolstoy M  Cowen JP  Baker ET  Fornari DJ  Rubin KH  Shank TM  Waldhauser F  Bohnenstiehl DR  Forsyth DW  Holmes RC  Love B  Perfit MR  Weekly RT  Soule SA  Glazer B 《Science (New York, N.Y.)》2006,314(5807):1920-1922

Two-thirds of Earth's surface is formed at mid-ocean ridges, yet sea-floor spreading events are poorly understood because they occur far beneath the ocean surface. At 9 degrees 50'N on the East Pacific Rise, ocean-bottom seismometers recently recorded the microearthquake character of a mid-ocean ridge eruption, including precursory activity. A gradual ramp-up in activity rates since seismic monitoring began at this site in October 2003 suggests that eruptions may be forecast in the fast-spreading environment. The pattern culminates in an intense but brief (approximately 6-hour) inferred diking event on 22 January 2006, followed by rapid tapering to markedly decreased levels of seismicity.  相似文献   

Differential targeting of Gbetagamma-subunit signaling with small molecules     

Bonacci TM  Mathews JL  Yuan C  Lehmann DM  Malik S  Wu D  Font JL  Bidlack JM  Smrcka AV 《Science (New York, N.Y.)》2006,312(5772):443-446

G protein betagamma subunits have potential as a target for therapeutic treatment of a number of diseases. We performed virtual docking of a small-molecule library to a site on Gbetagamma subunits that mediates protein interactions. We hypothesized that differential targeting of this surface could allow for selective modulation of Gbetagamma subunit functions. Several compounds bound to Gbetagamma subunits with affinities from 0.1 to 60 muM and selectively modulated functional Gbetagamma-protein-protein interactions in vitro, chemotactic peptide signaling pathways in HL-60 leukocytes, and opioid receptor-dependent analgesia in vivo. These data demonstrate an approach for modulation of G protein-coupled receptor signaling that may represent an important therapeutic strategy.  相似文献   

Losartan, an AT1 antagonist, prevents aortic aneurysm in a mouse model of Marfan syndrome     

Habashi JP  Judge DP  Holm TM  Cohn RD  Loeys BL  Cooper TK  Myers L  Klein EC  Liu G  Calvi C  Podowski M  Neptune ER  Halushka MK  Bedja D  Gabrielson K  Rifkin DB  Carta L  Ramirez F  Huso DL  Dietz HC 《Science (New York, N.Y.)》2006,312(5770):117-121

Aortic aneurysm and dissection are manifestations of Marfan syndrome (MFS), a disorder caused by mutations in the gene that encodes fibrillin-1. Selected manifestations of MFS reflect excessive signaling by the transforming growth factor-beta (TGF-beta) family of cytokines. We show that aortic aneurysm in a mouse model of MFS is associated with increased TGF-beta signaling and can be prevented by TGF-beta antagonists such as TGF-beta-neutralizing antibody or the angiotensin II type 1 receptor (AT1) blocker, losartan. AT1 antagonism also partially reversed noncardiovascular manifestations of MFS, including impaired alveolar septation. These data suggest that losartan, a drug already in clinical use for hypertension, merits investigation as a therapeutic strategy for patients with MFS and has the potential to prevent the major life-threatening manifestation of this disorder.  相似文献   

Clinical features and outcomes of phacoemulsification in 39 horses: a retrospective study (1993-2003)     

Fife TM  Gemensky-Metzler AJ  Wilkie DA  Colitz CM  Bras ID  Klages DC 《Veterinary ophthalmology》2006,9(5):361-368

OBJECTIVE: To identify visual outcome and postoperative complications following phacoemulsification of equine cataracts. ANIMALS: Records of 39 horses (55 eyes) with cataracts were reviewed. METHODS: Eyes with cataracts removed by phacoemulsification were included in the study. Data collected included age, breed, sex, stage and etiology of cataract, unilateral vs. bilateral involvement, and ultrasound findings. Horses were grouped by etiology of the cataract. Visual outcome and complications were evaluated for each group and the overall population. RESULTS: Immediately postoperatively 46 out of 47 eyes (98%) were sighted. Four weeks postoperatively 23 of 29 operated eyes (79%) were sighted [13/18 (72%) eyes with congenital/juvenile onset, 6/6 (100%) eyes with traumatic and 4/5 (90%) eyes with uveitis-induced cataracts], with 18 eyes lost to follow-up. The most common postoperative complications included corneal edema (19 eyes/40%), fibrin in the anterior chamber (11 eyes/23%), postoperative ocular hypertension (9 eyes/19%), synechia/dyscoria (9 eyes/19%), and hyphema (7 eyes/15%). CONCLUSIONS: Prognosis for vision is favorable for horses following phacoemulsification and planned posterior continuous tear circular capsulorrhexis. Success rates depend on age of patient, cause of cataract and pre-existing intraocular disease. The highest success rate occurred in eyes with traumatic cataracts.  相似文献