10 research outputs found
Biologic pathways associated with relapse in childhood acute lymphoblastic leukemia: a Children's Oncology Group study
Outcome for children with childhood acute lymphoblastic leukemia (ALL) who relapse is poor. To gain insight into the mechanisms of relapse, we analyzed gene-expression profiles in 35 matched diagnosis/relapse pairs as well as 60 uniformly treated children at relapse using the Affymetrix platform. Matched-pair analyses revealed significant differences in the expression of genes involved in cell-cycle regulation, DNA repair, and apoptosis between diagnostic and early-relapse samples. Many of these pathways have been implicated in tumorigenesis previously and are attractive targets for intervention strategies. In contrast, no common pattern of changes was observed among late-relapse pairs. Early-relapse samples were more likely to be similar to their respective diagnostic sample while we noted greater divergence in gene-expression patterns among late-relapse pairs. Comparison of expression profiles of early- versus late-relapse samples indicated that early-relapse clones were characterized by overexpression of biologic pathways associated with cell-cycle regulation. These results suggest that early-relapse results from the emergence of a related clone, characterized by the up-regulation of genes mediating cell proliferation. In contrast, late relapse appears to be mediated by diverse pathways
A Novel Fluorine Incorporated Band Engineered (BE) Tunnel (SiO2/ HfSiO/ SiO2) TANOS with Excellent Program/Erase & Endurance to 10^5 Cycles
We demonstrate for the first time a fluorine incorporated band- engineered (BE) tunnel oxide (SiO2/HfSiO/SiO2) TANOS with excellent program / erase (P/E) characteristics and endurance to 105 cycles. Incorporating fluorine in the tunnel dielectric improves Si/SiO2 interface resulting in excellent endurance of nearly constant over 3 V P/E window for at least 105 cycles. Fluorine also reduces interface state generation during retention by ~20%. Furthermore, Fluorine passivates bulk traps leading to as much as ~10times higher charge to breakdown (Qbd) and ~10-50times lower interface state density (Dit). Fluorine passivation for BE-TANOS is significant because it improves reliability assisting implementation of TANOS flash NVM beyond the 20 nm node
Tunable and reversible drug control of protein production via a self-excising degron
An effective method for direct chemical control over the production of specific proteins would be widely useful. We describe Small Molecule-Assisted Shutoff (SMASh), a technique in which proteins are fused to a degron that removes itself in the absence of drug, leaving untagged protein. Clinically tested HCV protease inhibitors can then block degron removal, inducing rapid degradation of subsequently synthesized protein copies. SMASh allows reversible and dose-dependent shutoff of various proteins in multiple mammalian cell types and in yeast. We also used SMASh to confer drug responsiveness onto a RNA virus for which no licensed inhibitors exist. As SMASh does not require permanent fusion of a large domain, it should be useful when control over protein production with minimal structural modification is desired. Furthermore, as SMASh only involves a single genetic modification and does not rely on modulating protein-protein interactions, it should be easy to generalize to multiple biological contexts
Delayed colorectal cancer care during covid-19 pandemic (decor-19). Global perspective from an international survey
Background
The widespread nature of coronavirus disease 2019 (COVID-19) has been unprecedented. We sought to analyze its global impact with a survey on colorectal cancer (CRC) care during the pandemic.
Methods
The impact of COVID-19 on preoperative assessment, elective surgery, and postoperative management of CRC patients was explored by a 35-item survey, which was distributed worldwide to members of surgical societies with an interest in CRC care. Respondents were divided into two comparator groups: 1) ‘delay’ group: CRC care affected by the pandemic; 2) ‘no delay’ group: unaltered CRC practice.
Results
A total of 1,051 respondents from 84 countries completed the survey. No substantial differences in demographics were found between the ‘delay’ (745, 70.9%) and ‘no delay’ (306, 29.1%) groups. Suspension of multidisciplinary team meetings, staff members quarantined or relocated to COVID-19 units, units fully dedicated to COVID-19 care, personal protective equipment not readily available were factors significantly associated to delays in endoscopy, radiology, surgery, histopathology and prolonged chemoradiation therapy-to-surgery intervals. In the ‘delay’ group, 48.9% of respondents reported a change in the initial surgical plan and 26.3% reported a shift from elective to urgent operations. Recovery of CRC care was associated with the status of the outbreak. Practicing in COVID-free units, no change in operative slots and staff members not relocated to COVID-19 units were statistically associated with unaltered CRC care in the ‘no delay’ group, while the geographical distribution was not.
Conclusions
Global changes in diagnostic and therapeutic CRC practices were evident. Changes were associated with differences in health-care delivery systems, hospital’s preparedness, resources availability, and local COVID-19 prevalence rather than geographical factors. Strategic planning is required to optimize CRC care