Coronaviruses contain a positive-sense singlestranded genomic (g) RNA, which encodes nonstructural proteins. Several subgenomic mRNAs (sgmRNAs) encoding structural proteins are generated by template switching from the body transcription regulatory sequence (TRS) to the leader TRS. The process preferentially generates shorter sgmRNA. Appropriate readthrough of body TRSs is required to produce longer sgmRNAs and full-length gRNA. We find that phosphorylation of the viral nucleocapsid (N) by host glycogen synthase kinase-3 (GSK-3) is required for template switching. GSK-3 inhibition selectively reduces the generation of gRNA and longer sgmRNAs, but not shorter sgmRNAs. N phosphorylation allows recruitment of the RNA helicase DDX1 to the phosphorylated-N-containing complex, which facilitates template readthrough and enables longer sgmRNA synthesis. DDX1 knockdown or loss of helicase activity markedly reduces the levels of longer sgmRNAs. Thus, coronaviruses employ a unique strategy for the transition from discontinuous to continuous transcription to ensure balanced sgmRNAs and full-length gRNA synthesis.

PurposeTo retrospectively evaluate the clinical and technical factors related to the outcomes of endovascular management in patients with head-and-neck cancers associated with post-irradiated carotid blowout syndrome (PCBS).Materials and MethodsBetween 2000 and 2013, 96 patients with PCBS underwent endovascular management. The 40 patients with the pathological lesions located in the external carotid artery were classified as group 1 and were treated with embolization. The other 56 patients with the pathological lesions located in the trunk of the carotid artery were divided into 2 groups as follows: group 2A comprised the 38 patients treated with embolization, and group 2B comprised the 18 patients treated with stent-graft placement. Fisher’s exact test was used to examine endovascular methods, clinical severities, and postprocedural clinical diseases as predictors of outcomes.ResultsTechnical success and immediate hemostasis were achieved in all patients. The results according to endovascular methods (group 1 vs 2A vs 2B) were as follows: technical complication (1/40[2.5%] vs 9/38[23.7%] vs 9/18[50.0%], P = 0.0001); rebleeding (14/40[35.0%] vs 5/38[13.2%] vs 7/18[38.9%]), P = 0.0435). The results according to clinical severity (acute vs ongoing PCBS) were as follows: technical complication (15/47[31.9%] vs 4/49[8.2%], P = 0.0035); rebleeding (18/47[38.3%] vs 8/49[16.3%], P = 0.0155). The results according to post-procedural clinical disease (regressive vs progressive change) were as follows: alive (14/21[66.7%] vs 8/75[10.7%], P<0.0001); survival time (34.1±30.6[0.3–110] vs 3.6±4.0[0.07–22] months, P<0.0001).ConclusionThe outcomes of endovascular management of PCBS can be improved by taking embolization as a prior way of treatment, performing endovascular intervention in slight clinical severity and aggressive management of the post-procedural clinical disease.

An efficient and morphologically stable pyrimidine-containing spirobifluorene-cored oligoaryl, 2,7-bis͓2-͑4-tert-butylphenyl͒pyrimidine-5-yl͔-9,9Ј-spirobifluorene ͑TBPSF͒, as an emitter or a host for blue organic light-emitting devices ͑OLEDs͒, is reported. The steric hindrance inherent with the molecular structure renders the material a record-high neat-film photoluminescence ͑PL͒ quantum yield of 80% as a pure blue emitter ͑PL peak at 430 nm͒ of low molecular weight, and a very high glass-transition temperature (T g) of 195°C. Blue OLEDs employing this compound as the emitter or the emitting host exhibit unusual endurance for high currents over 5000 mA/cm 2. When TBPSF is used as a host for perylene in a blue OLED, maximal brightness of ϳ80 000 cd/m 2 had been achieved, representing the highest values reported for blue OLEDs under dc driving.

Spiro-FPA, a novel blue emitter, in which two identical anthracene luminophores are linked orthogonally around a spirobifluorene core, has been synthesized and characterized. The introduction of a spiro linkage into the structure of spiro-FPA leads to a reduction in crystallization tendency and an increase in glass transition temperature relative to the monomeric units. In addition, the tetrahedral nature of the carbon atom at the spiro center preserves the optical and electrochemical characteristics of the pristine anthracene units. As demonstrated by AFM measurements, high-quality amorphous films of spiro-FPA with good morphological stability can be prepared by vapor deposition. Organic EL devices constructed using a 1.0-wt % TBP-doped spiro-FPA emitting layer produce bright blue emissions with a high luminescence efficiency of 4.9 cd/A (2.07 lm/W).