Blank field sources (BFS) are good candidates for hosting dim isolated neutron stars (DINS). The results of a search of BFS in the ROSAT HRI images are revised. We then focus on transient BFS, ...arguing that they belong to a rather large population. The perspectives of future research on DINS are then discussed.
The aim of our study was to investigate the occurrence of osteonecrosis of the jaw (ONJ) after implementation of dental preventive measures before starting bisphosphonates (BPs) therapy and during ...treatment. All consecutive patients with bone lesions eligible for BPs treatment were prospectively evaluated. Before starting BPs, each patient underwent a strict dental preventive program with a specialized odontoiatric team. The odontoiatric evaluation identified patients with oral pathologies or inadequate oral hygiene and provided a dental preventive treatment. From April 2007 to April 2012, 254 patients were enrolled. After excluding patients due to previous BPs treatment, 212 patients with a mean age of 74 years (range 37–95) were included. On average, patients received 9.7 treatment cycles (range 1–48). No ONJ was recorded (0.0 %; 95 % confidence interval CI 0.0–1.4). Comparing this risk with that observed in a previous cohort who did not receive dental prevention (16/186, 8.6 %; 95 % CI 4.2–15.3 %), we observed clear efficacy in preventing ONJ (relative risk reduction: 100 %, 95 % CI 86–100 %,
P
< 0.0001). We developed a strict three-step prevention program that is able to decrease ONJ incidence and the need for destructive surgery with permanent sequelae. We demonstrated that ONJ could be effectively prevented. We recommend a mandatory preventive program involving a multidisciplinary team for all patients starting BPs.
Background: In patients with digestive endocrine tumours, complete pre-operative staging is essential in planning proper management and evaluating treatment efficacy. To date, somatostatin receptor ...scintigraphy (SRS) is considered the ‘gold standard’ imaging procedure, and very few data are available concerning the use of helical computed tomography (hCT). This study aimed to determine the diagnostic accuracy and the ability to modify the surgical management of hCT, alone or combined with SRS. Patients and methods: Sixty patients were staged before surgery by hCT, SRS and tumour markers, and included in group 1 if suitable for radical surgery, otherwise in group 2. All patients underwent laparotomy followed by subsequent re-staging. Results: SRS sensitivity was 77%, 48% and 67% for primary, lymph-node and liver lesions, respectively. hCT sensitivity was 94%, 69% and 94% for primary, lymph-node and liver lesions, respectively (P = 0.02 versus SRS, for liver lesions). During pre-operative evaluation, hCT correctly staged 92% and SRS 75% of patients (P = 0.02). hCT provided additional information in 17% of patients. Conclusions: Since hCT has been shown to be extremely accurate, providing essential information for the planning of surgical treatment compared with that of SRS, both techniques should be used in the pre-operative work-up of digestive endocrine tumours.
Previous resistance analyses of Arabidopsis thaliana mutants knocked out for eukaryotic translation initiation factors showed that disruption of the At-eIF(iso)4E or both the At-eIF(iso)4G1 and ...At-eIF(iso)4G2 genes resulted in resistance against turnip mosaic virus (TuMV). This study selected TuMV virulent variants that overcame this resistance and showed that two independent mutations in the region coding for the viral genome-linked protein (VPg) were sufficient to restore TuMV virulence in At-eIF(iso)4E and At-eIF(iso)4G1xAt-eIF(iso)4G2 knockout plants. As a VPg–eIF(iso)4E interaction has been shown previously to be critical for TuMV infection, a systematic analysis of the interactions between A. thaliana eIF4Es and VPgs of virulent and avirulent TuMVs was performed. The results suggest that virulent TuMV variants may use an eIF4F-independent pathway.
Kincaid Shelter (Uvalde County, Texas) contains a sequence of vertebrate and cultural remains spanning from the late Pleistocene to Historic. Kincaid Shelter perhaps is best known for its Paleoindian ...component, including a cobblestone floor interpreted as a Clovis habitation surface. Zone 3 lacustrine sediments are beneath that cobblestone floor and yielded a diverse late Pleistocene vertebrate fauna. Recovered in 1948, the assemblage has never been formally studied or described. The current analysis focuses on the composition, paleoecology, and taphonomy of the Zone 3 faunal assemblage to establish and clarify this important late Pleistocene record. Sixteen vertebrate taxa are represented. Large mammals predominate, but reptiles, including American alligator, and a bird also occur. The presence of Bison antiquus and Panthera atrox indicate a late Pleistocene (Rancholabrean Land Mammal Age) age for the faunal assemblage. The Zone 3 faunal composition is typical of latest Pleistocene faunas from the Great Plains and supports an interpretation of a grassland biome.
We report the results of Swift X-Ray Telescope (XRT) observations of GRB 050318. This event triggered the Burst Alert Telescope (BAT) aboard Swift and was followed-up with XRT and UVOT for ...11 consecutive orbits starting from 54 min after the trigger. A previously unknown fading X-ray source was detected and accurately monitored. The source was found to decrease in intensity with time and a clear temporal break occurring at ~18 000 s after the trigger was observed. The X-ray light curve was found to be consistent with a broken power-law with decay indices $-1.17\pm 0.08$ and $-2.10^{+0.22}_{-0.24}$ before and after the break. The spectrum of the X-ray afterglow was well described by a photoelectrically absorbed power-law with energy index of $-1.09\pm0.09$. No evidence of spectral evolution was found. We compare these results with those obtained with UVOT and separately reported and refine the data analysis of BAT. We discuss our results in the framework of a collimated fireball model and a synchrotron radiation emission mechanism. Assuming the GRB redshift derived from the farthest optical absorption complex ($z = 1.44$), the event is fully consistent with the $E_{\rm{p}}$–$E_{\rm{iso}}$ correlation.
Sphingosine kinase 1 (SK1) catalyses the generation of sphingosine 1-phosphate (S1P), a bioactive phospholipid that influences a diverse range of cellular processes, including proliferation, ...survival, adhesion, migration, morphogenesis and differentiation. SK1 is controlled by various mechanisms, including transcriptional regulation, and post-translational activation by phosphorylation and protein–protein interactions which can regulate both the activity and localisation of this enzyme. To gain a better understanding of the regulatory mechanisms controlling SK1 activity and function we performed a yeast two-hybrid screen to identify SK1-interacting proteins. Using this approach we identified that SK1 interacts with subunit 7 (η) of cytosolic chaperonin CCT (chaperonin containing t-complex polypeptide, also called TRiC for TCP-1 ring complex), a hexadecameric chaperonin that binds unfolded polypeptides and mediates their folding and release in an ATP-dependent manner. Further analysis of the SK1–CCTη interaction demonstrated that other CCT/TRiC subunits also associated with SK1 in HEK293T cell lysates in an ATP-sensitive manner, suggesting that the intact, functional, multimeric CCT/TRiC complex associated with SK1. Furthermore, pulse-chase studies indicated that CCT/TRiC binds specifically to newly translated SK1. Finally, depletion of functional CCT/TRiC through the use of RNA interference in HeLa cells or temperature sensitive CCT yeast mutants reduced cellular SK1 activity. Thus, combined this data suggests that SK1 is a CCT/TRiC substrate, and that this chaperonin facilitates folding of newly translated SK1 into its mature active form.
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