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Spinal instability neoplastic score: an analysis of reliability and validity from the spine oncology study group.
No full textPurposeStandardized indications for treatment of tumor-related spinal instability are hampered by the lack of a valid and reliable classification system. The objective of this study was to determine the interobserver reliability, intraobserver reliability, and predictive validity of the Spinal Instability Neoplastic Score (SINS).MethodsClinical and radiographic data from 30 patients with spinal tumors were classified as stable, potentially unstable, and unstable by members of the Spine Oncology Study Group. The median category for each patient case (consensus opinion) was used as the gold standard for predictive validity testing. On two occasions at least 6 weeks apart, each rater also scored each patient using SINS. Each total score was converted into a three-category data field, with 0 to 6 as stable, 7 to 12 as potentially unstable, and 13 to 18 as unstable.ResultsThe κ statistics for interobserver reliability were 0.790, 0.841, 0.244, 0.456, 0.462, and 0.492 for the fields of location, pain, bone quality, alignment, vertebral body collapse, and posterolateral involvement, respectively. The κ statistics for intraobserver reliability were 0.806, 0.859, 0.528, 0.614, 0.590, and 0.662 for the same respective fields. Intraclass correlation coefficients for inter- and intraobserver reliability of total SINS score were 0.846 (95% CI, 0.773 to 0.911) and 0.886 (95% CI, 0.868 to 0.902), respectively. The κ statistic for predictive validity was 0.712 (95% CI, 0.676 to 0.766).ConclusionSINS demonstrated near-perfect inter- and intraobserver reliability in determining three clinically relevant categories of stability. The sensitivity and specificity of SINS for potentially unstable or unstable lesions were 95.7% and 79.5%, respectively
The Logic of Government’s Response to Protests in China New Evidence from Protests Recorded in Social Media
No full textScholarship on protests in China, though prolific in recent years, faces serious data issues. Since there is no comprehensive dataset for a systematic analysis of protests in China, previous scholars can only quantitatively study the pattern of repression of protests. Most studies related to the protest outcomes or government responses in China can only use qualitative methods. Drawing on an original dataset of 508 protests I collected from the Wickdonna website, this article first offers a systematic analysis of the response pattern to protests in China. My paper shows that domestic media coverage and the government's perception of political threats and economic costs are the most significant determinants of the government's response to a protest. While the size of the protest, the disruptiveness of the protest, and the geographical location of the protest have no direct impact on the government's results, they significantly increase the odds of media coverage of a protest. Overall, my paper contributes to a more comprehensive understanding of daily contentions in authoritarian China.</p
ASFA Category IV becomes Category I: Idiopathic thrombotic thrombocytopenic purpura in a patient with presumed gemcitabine-induced thrombotic microangiopathy.
No full textIn the implementation of American Society for Apheresis national guidelines, the decision for therapeutic plasma exchange may be confounded by a clinical presentation that fits both a Category I and IV designation. We report the case of a 45-year-old female who presented with concern for a Category IV disorder, gemcitabine-induced thrombotic microangiopathy, and was ultimately diagnosed with a Category I disorder, idiopathic thrombotic thrombocytopenic purpura. This case highlights the importance of ruling out idiopathic TTP by a thorough evaluation for ADAMTS13 activity and inhibitor, even when an alternate thrombotic microangiopathy diagnosis may be likely
A Deep Learning Model for V50%, V60%, and V66.7% Prediction in LINAC-based Treatment Planning of Single-Iso-Multiple-Targets (SIMT) Stereotactic Radiosurgery (SRS)
No full textBrain metastases are a common complication of many types of cancer, including lung, breast, and melanoma. Approximately 30-40% of patients develop brain metastases that originate from primary systemic tumors during the course of cancer treatment. One treatment method is a LINAC-based single-isocenter multiple-target (SIMT) stereotactic radiosurgery (SRS). High plan quality has been one of the important goals in radiotherapy treatment planning. Generation of a high quality SRS treatment plan, particularly a SIMT plan, usually requires planners’ extensive planning experience, multiple runs of planning and trial-and-error, and frequent communication among planners, physicians and other radiation oncology team members. In clinical practice with potentially limited resources, SIMT SRS planning could be time-consuming and may have large variations in plan dosimetric quality. Therefore, an estimation of achievable dosimetric outcome can help reduce plan quality variation and improve planning efficiency. Assuming 20Gy in a single fraction of treatment, the volume of normal brain tissue receiving 10Gy (V50%), 12Gy (V60%), and 13Gy (V66.7%) are known predictors of brain tissue toxicity, or radionecrosis. We developed deep learning networks for the prediction of V50%, V60%, and V66.7% based on each patient’s target delineation. A prediction of achievable V10Gy, V12Gy, and V13Gy (assuming 20Gy x 1fx) can assist physicians in the determination of fractionation schemes (i.e., single fx vs. multiple fx). Such predictions can be used as guidelines for planners to generate a SIMT plan more rapidly with reduced dosimetric variability. A key technical innovation of this work is the spherical projection design: by projecting target distribution on a spherical surface, the target distribution in 3D is collapsed to a polar-azimuthal angular distribution map. This transformation enables a dimensional reduction for deep learning input without losing volumetric information.
Our results indicate promising potential but there is a need for further work to improve the accuracy of our predictions.</p
The Solution Structures and Interaction of SinR and SinI: Elucidating the Mechanism of Action of the Master Regulator Switch for Biofilm Formation in Bacillus subtilis.
No full textBacteria have developed numerous protection strategies to ensure survival in harsh environments, with perhaps the most robust method being the formation of a protective biofilm. In biofilms, bacterial cells are embedded within a matrix that is composed of a complex mixture of polysaccharides, proteins, and DNA. The gram-positive bacterium Bacillus subtilis has become a model organism for studying regulatory networks directing biofilm formation. The phenotypic transition from a planktonic to biofilm state is regulated by the activity of the transcriptional repressor, SinR, and its inactivation by its primary antagonist, SinI. In this work, we present the first full-length structural model of tetrameric SinR using a hybrid approach combining high-resolution solution nuclear magnetic resonance (NMR), chemical cross-linking, mass spectrometry, and molecular docking. We also present the solution NMR structure of the antagonist SinI dimer and probe the mechanism behind the SinR-SinI interaction using a combination of biochemical and biophysical techniques. As a result of these findings, we propose that SinI utilizes a residue replacement mechanism to block SinR multimerization, resulting in diminished DNA binding and concomitant decreased repressor activity. Finally, we provide an evidence-based mechanism that confirms how disruption of the SinR tetramer by SinI regulates gene expression
Complications and intercenter variability of three-column osteotomies for spinal deformity surgery: a retrospective review of 423 patients.
No full textObjectThree-column resection osteotomies (3COs) are commonly performed for sagittal deformity but have high rates of reported complications. Authors of this study aimed to examine the incidence of and intercenter variability in major intraoperative complications (IOCs), major postoperative complications (POCs) up to 6 weeks postsurgery, and overall complications (that is, both IOCs and POCs). They also aimed to investigate the incidence of and intercenter variability in blood loss during 3CO procedures.MethodsThe incidence of IOCs, POCs, and overall complications associated with 3COs were retrospectively determined for the study population and for each of 8 participating surgical centers. The incidence of major blood loss (MBL) over 4 L and the percentage of total blood volume lost were also determined for the study population and each surgical center. Complication rates and blood loss were compared between patients with one and those with two osteotomies, as well as between patients with one thoracic osteotomy (ThO) and those with one lumbar or sacral osteotomy (LSO). Risk factors for developing complications were determined.ResultsRetrospective review of prospectively acquired data for 423 consecutive patients who had undergone 3CO at 8 surgical centers was performed. The incidence of major IOCs, POCs, and overall complications was 7%, 39%, and 42%, respectively, for the study population overall. The most common IOC was spinal cord deficit (2.6%) and the most common POC was unplanned return to the operating room (19.4%). Patients with two osteotomies had more POCs (56% vs 38%, p = 0.04) than the patients with one osteotomy. Those with ThO had more IOCs (16% vs 6%, p = 0.03), POCs (58% vs 34%, p ConclusionsGiven the complexity of 3COs for spinal deformity, it is important for spine surgeons to understand the risk factors and complication rates associated with these procedures. In this study, the overall incidence of major complications following 3CO procedures was 42%. Risks for developing complications included an older age (> 60 years), two osteotomies, ThO, and MBL
Modulating the Dynamics of Charged and Photoexcited-States in Nanoscale Systems
No full text Light-matter interactions are fundamental to many critical emerging technologies – such as photovoltaics, photonic sensing, and information transmission – that rely upon the efficient capture of light and its conversion to useful energetic states. However, to realize these technologies as a viable future we must first understand the fundamental processes which govern and dictate the energetic, spatial, and temporal identity of materials following photoexcitation. As is suggested by the term “light-matter” both the qualities of the light and the structural composition of the material will influence these characteristics resulting from their interaction. This dissertation investigates how photoexcitation conditions and material structure can be leveraged to modulate the energetic and charged states, and the dynamics thereof, which arise following photoexcitation of nanoscale and molecular systems. Employing ultrafast pump-probe transient absorption spectroscopy, this work characterizes the transient states which arise from photoexcitation of: (i) single-walled carbon nanotubes (SWNTs) wrapped by aryleneethynylene semiconducting polymers; (ii) covalently linked ethyne bridged porphyrin donor, rylene acceptor, molecular “ratchets” and (iii) rylene chromophores covalently linked to amino acid models. In nanoscale systems, this work highlights how the electronic structure of 1-dimensional SWNTs: (i) enable a complex interplay of excitation fluence dependent multi-body interactions, arising from the multitude of photogenerated energetic states, which may be harnessed to modulate the nature and lifetime of charge separated states and; (ii) give rise to a collection of heretofore ill-defined photoexcited-states with low energy optical transitions. At a molecular level, this work demonstrates how molecular structures can be engineered to: (i) utilize quantum coherence in a donor-acceptor “ratchet” which exhibit excitation frequency dependent uphill energy transfer, via vibronic mixing, to undergo electronically irreversible charge transfer and; (ii) selectively photooxidize amino acid analogues in biologically reminiscent photoreactions. These findings presented herein may be used to guide optoelectronic designs which efficiently guide and harness the charged and energetic species which arise from photoexcitation.</p
Characterization of the <i>tilt (tt)</i> phenotype in <i>Drosophila melanogaster</i>.
No full textIn the early 20th century, Calvin Bridges and Thomas Morgan identified a number of spontaneous mutations that displayed visible phenotypes in adult flies and subsequent analysis of these mutations over the past century have provided fundamental insights into subdisciplines of biology such as genetics, developmental, and cell biology. One of the mutations they identified in 1915 was named tilt ( tt ) and was described by Bridges and Morgan as having two visible phenotype characteristics in the wing. The wings were "held out at a wider angle from the body" and had a break in wing vein L3. Subsequent analysis of the tilt phenotype identified another phenotype: the wings were missing a varying number of campaniform sensilla on L3. Though Bridges and Morgan provided an ink drawing of the wing posture phenotype, only the vein and campaniform sensilla loss images have been published. Here we confirm and document the tilt phenotypes that have been previously described. We also show the penetrance of these phenotypes: the vein break and the distinct outward wing posture have decreased since its discovery
Crossing the river by feeling for the stones: contesting models of marketization and the development of China’s long-term care services
No full textProbable trauma associated sleep disorder in post-9/11 US Veterans
No full textAbstractStudy ObjectivesThe purpose of this study was to (1) estimate trauma associated sleep disorder (TASD) prevalence among post-9/11 era veterans and to describe differences in service and comorbid mental health clinical characteristics among individuals with and without probable TASD, and (2) estimate TASD prevalence and characteristics of reported traumatic experiences stratified by sex.MethodsWe used cross-sectional data from the post-deployment mental health study of post-9/11 veterans, which enrolled and collected baseline data from 2005 to 2018. We classified veterans as having probable TASD using self-reported measures: traumatic experiences from the traumatic life events questionnaire (TLEQ) and items from the Pittsburgh sleep quality index with Addendum for posttraumatic stress disorder (PTSD) mapped to TASD diagnostic criteria and ascertained mental health diagnoses (PTSD, major depressive disorder [MDD]) via Structured Clinical Interview for DSM-IV. We calculated effect sizes as prevalence ratios (PR) for categorical variables and Hedges’ g for continuous variables.ResultsOur final sample included 3618 veterans (22.7% female). TASD prevalence was 12.1% (95% CI: 11.1% to 13.2%) and sex-stratified prevalence was similar for female and male veterans. Veterans with TASD had a much higher comorbid prevalence of PTSD (PR: 3.72, 95% CI: 3.41 to 4.06) and MDD (PR: 3.93, 95% CI: 3.48 to 4.43). Combat was the highest reported most distressing traumatic experience among veterans with TASD (62.6%). When stratifying by sex, female veterans with TASD had a wider variety of traumatic experiences.ConclusionsOur results support the need for improved screening and evaluation for TASD in veterans, which is currently not performed in routine clinical practice.</jats:sec