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1.
Comput Inform Nurs ; 40(5): 317-324, 2022 May 01.
Article in English | MEDLINE | ID: mdl-35523228

ABSTRACT

The COVID-19 pandemic has made decisions about resource allocation and reallocation real possibilities even in high-resource settings. In April 2020, in preparation for such an eventuality, Atlantic Health System began to develop a real-time instrument built into the EMR to assist with such decisions. The instrument calculated the modified Sequential Organ Failure Assessment for all patients admitted, in real time, to assist triage teams make decisions if crisis standards of care were declared. A pilot assessment of the instrument was performed using retrospective data by nine members of the triage teams, who were asked to identify the six patients at highest risk of reallocation. Agreement about which patients were at highest risk of resource reallocation was good, but not perfect. All raters agreed on five of the six patients, but only seven of nine agreed on the final patient. Among the six consensus selections for reallocation, five died prior to hospital discharge. All patients at highest risk of reallocation had a predicted life expectancy of less than 1 year. In conclusion, the instrument was easy to use, and the concordance among raters was good but not perfect. Predicted life expectance was a major determinant of the triage score.


Subject(s)
COVID-19 , Pandemics , Electronics , Humans , Retrospective Studies , Triage
2.
Nat Commun ; 12(1): 4659, 2021 Aug 03.
Article in English | MEDLINE | ID: mdl-34344883

ABSTRACT

The lunar surface is ancient and well-preserved, recording Solar System history and planetary evolution processes. Ancient basin-scale impacts excavated lunar mantle rocks, which are expected to remain present on the surface. Sampling these rocks would provide insight into fundamental planetary processes, including differentiation and magmatic evolution. There is contention among lunar scientists as to what lithologies make up the upper lunar mantle, and where they may have been exposed on the surface. We review dynamical models of lunar differentiation in the context of recent experiments and spacecraft data, assessing candidate lithologies, their distribution, and implications for lunar evolution.

3.
J Clin Oncol ; 35(7): 718-726, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28068178

ABSTRACT

Purpose Squamous cell carcinoma of the anal canal (SCCAC) is characterized by high locoregional failure (LRF) rates after sphincter-preserving definitive chemoradiation (CRT) and is typically associated with anogenital human papilloma virus infection. Because cetuximab enhances the effect of radiation therapy in human papilloma virus-associated oropharyngeal squamous cell carcinoma, we hypothesized that adding cetuximab to CRT would reduce LRF in SCCAC. Methods Sixty-one patients with stage I to III SCCAC received CRT including cisplatin, fluorouracil, and radiation therapy to the primary tumor and regional lymph nodes (45 to 54 Gy) plus eight once-weekly doses of concurrent cetuximab. The study was designed to detect at least a 50% reduction in 3-year LRF rate (one-sided α, 0.10; power 90%), assuming a 35% LRF rate from historical data. Results Poor risk features included stage III disease in 64% and male sex in 20%. The 3-year LRF rate was 23% (95% CI, 13% to 36%; one-sided P = .03) by binomial proportional estimate using the prespecified end point and 21% (95% CI, 7% to 26%) by Kaplan-Meier estimate in a post hoc analysis using methods consistent with historical data. Three-year rates were 68% (95% CI, 55% to 79%) for progression-free survival and 83% (95% CI, 71% to 91%) for overall survival. Grade 4 toxicity occurred in 32%, and 5% had treatment-associated deaths. Conclusion Although the addition of cetuximab to chemoradiation for SCCAC was associated with lower LRF rates than historical data with CRT alone, toxicity was substantial, and LRF still occurs in approximately 20%, indicating the continued need for more effective and less toxic therapies.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Anus Neoplasms/drug therapy , Anus Neoplasms/radiotherapy , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/radiotherapy , Adult , Aged , Anus Neoplasms/immunology , Anus Neoplasms/pathology , Carcinoma, Squamous Cell/immunology , Carcinoma, Squamous Cell/pathology , Cetuximab/administration & dosage , Chemoradiotherapy , Cisplatin/administration & dosage , Disease-Free Survival , Female , Fluorouracil/administration & dosage , Humans , Immunocompetence , Male , Middle Aged , Neoplasm Staging , Survival Rate
4.
Methods ; 103: 128-37, 2016 07 01.
Article in English | MEDLINE | ID: mdl-27090005

ABSTRACT

Designing self-assembling RNA ring structures based on known 3D structural elements connected via linker helices is a challenging task due to the immense number of motif combinations, many of which do not lead to ring-closure. We describe an in silico solution to this design problem by combinatorial assembly of RNA 3-way junctions, bulges, and kissing loops, and tabulating the cases that lead to ring formation. The solutions found are made available in the form of a web-accessible Ring Catalog. As an example of a potential use of this resource, we chose a predicted RNA square structure consisting of five RNA strands and demonstrate experimentally that the self-assembly of those five strands leads to the formation of a square-like complex. This is a demonstration of a novel "design by catalog" approach to RNA nano-structure generation. The URL https://rnajunction.ncifcrf.gov/ringdb can be used to access the resource.


Subject(s)
RNA/chemistry , Databases, Nucleic Acid , Dimerization , Nanostructures , Nucleic Acid Conformation , Software
5.
Biochim Biophys Acta ; 1774(1): 78-85, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17118726

ABSTRACT

Factor for inversion stimulation (FIS) is a 98-residue homodimeric DNA-binding protein involved in several different cellular processes including DNA inversion and the regulation of multiple genes. FIS contains a flexible and functionally important N-terminus followed by four helices (A-D), the last two of which consist of the DNA-binding region. Helix B, which comprises the main dimerization interface has a 20 degrees kink at its center that was originally thought to be caused by the presence of a proline at position 61. However, it was later shown that the kink remained largely intact and that FIS retained its native-like function when the proline was mutated to an alanine. We previously showed that the P61A mutation increased the stability of FIS, but decreased its equilibrium denaturation cooperativity apparently due to preferential stabilization of the B-helix. Here we studied a peptide of P61A FIS, corresponding to residues 26-71 (26-71(A3) FIS), which encompasses the dimer interface (helices A and B). Circular dichroism (CD) and size-exclusion chromatography/multi-angle light scattering showed that the peptide was alpha-helical and dimeric, respectively, as expected based on the 3D structure of FIS. Urea-induced equilibrium denaturation experiments monitored by far-UV CD revealed a concentration-dependent transition, and data analysis based on a N2<-->2U model yielded a DeltaG of approximately -10 kcal/mol. Our results suggest that 26-71(A3) FIS can form a stable dimeric structure despite lacking the N- and C-terminus of native FIS.


Subject(s)
Factor For Inversion Stimulation Protein/chemistry , Factor For Inversion Stimulation Protein/genetics , Peptide Fragments/chemistry , Amino Acid Sequence , Amino Acid Substitution , Circular Dichroism , Dimerization , Models, Molecular , Molecular Sequence Data , Protein Denaturation , Protein Structure, Secondary
6.
Protein Sci ; 11(7): 1671-80, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12070319

ABSTRACT

The Factor for Inversion Stimulation (FIS) is a dimeric DNA binding protein found in enteric bacteria that is involved in various cellular processes, including stimulation of certain specialized DNA recombination events and transcription regulation of a large number of genes. The intracellular FIS concentration, when cells are grown in rich media, varies dramatically during the early logarithmic growth phase. Its broad range of concentrations could potentially affect the nature of its quaternary structure, which in turn, could affect its ability to function in vivo. Thus, we examined the stability of FIS homodimers under a wide range of concentrations relevant to in vivo expression levels. Its urea-induced equilibrium denaturation was monitored by far- and near-UV circular dichroism (CD), tyrosine fluorescence, and tyrosine fluorescence anisotropy. The denaturation transitions obtained were concentration-dependent and showed similar midpoints (C(m)) and m values, suggesting a two-state denaturation process involving the native dimer and unfolded monomers (N(2) <--> 2U). The DeltaG(H(2)O) for the unfolding of FIS determined from global and individual curve fitting was 14.2 kcal/mole. At concentrations <9 microM, the FIS dimer began to dissociate, as noted by the change in CD signal and size-exclusion high-pressure liquid chromatography retention times and peak width. The estimated dimer dissociation constant based on the CD and size-exclusion chromatography data is in the micromolar range, resulting in a DeltaG(H(2)O) of at least 5 kcal/mole less than that calculated from the urea denaturation data. This discrepancy suggests a deviation from a two-state denaturation model, perhaps due to a marginally stable monomeric intermediate. These observations have implications for the stability and function of FIS in vivo.


Subject(s)
Escherichia coli Proteins/chemistry , Escherichia coli/metabolism , Factor For Inversion Stimulation Protein/chemistry , Chromatography, High Pressure Liquid , Circular Dichroism , Escherichia coli Proteins/physiology , Factor For Inversion Stimulation Protein/physiology , Fluorescence , Fluorescence Polarization , Kinetics , Protein Denaturation , Tyrosine/metabolism , Urea/metabolism
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