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Marschall B. Berkes Joshua S. Dines Jacqueline F. Birnbaum Lionel E. Lazaro Tristan C. Lorich Milton T. M. Little Joseph T. Nguyen Dean G. Lorich 《HSS journal》2015,11(3):192-197
Background
Convention dictates that an axillary view be obtained when evaluating proximal humerus fractures (PHF). However, the axillary view is frequently omitted because of pain and technical considerations. Furthermore, its diagnostic utility is unclear in this setting.Questions/Purposes
The purpose of this study was to (1) determine the rate of obtaining an adequate axillary X-ray and complete shoulder series at a level I trauma center, (2) understand the cost of ordering and attempting an axillary radiograph, and (3) determine if axillary radiographs influence the management of PHF.Patients and Methods
PHF treated between 2009 and 2011 that were ordered for an AP, scapular Y, and axillary view was identified. The types of radiographs actually obtained were recorded. The cost of obtaining three views and a single view of the shoulder with X-ray was determined. Lastly, three surgeons reviewed 42 PHF, both with and without an axillary view (AV), and treatment recommendations were compared.Results
30% of PHF in this series had an adequate axillary view, and 14% received a complete trauma series. No factors could be identified that were associated with successfully obtaining an axillary view. Reviewers demonstrated substantial intraobserver reliability (κ = 0.759–0.808) regarding treatment recommendations for PHF with and without the axillary view. The addition of the AV had minimal influence on treatment recommendations.Conclusion
Considering that the axillary view for PHF is painful, labor-intensive, costly, and does not appear to provide additional diagnostic value, orthopedic surgeons can consider foregoing the use of the axillary view when evaluating and treating PHF, particularly if other advanced imaging is utilized.Electronic supplementary material
The online version of this article (doi:10.1007/s11420-015-9445-9) contains supplementary material, which is available to authorized users. 相似文献54.
Leppik IE Bergey GK Ramsay RE Rowan AJ Gidal BE Birnbaum AK Elliott MB 《Geriatrics》2004,59(12):14-8, 22-4
Incidence of epilepsy increases rapidly after age 65; recent studies indicate that approximately 10% of nursing home residents are being treated with antiepileptic drugs (AEDs). Almost all are being treated with first generation AEDs. The average nursing home patient receives six medications, has age-related changes in protein binding, decreases in hepatic and renal clearance, and may have alterations in gastrointestinal absorption. AEDs that do not have drug-drug interactions, are not metabolized by the liver, and are readily absorbed may offer benefits in this population. New studies are demonstrating that the first generation AEDs have a number of shortcomings for treating older patients, whereas some of the newer AEDs may overcome these limitations. This paper reviews the present knowledge base and compares properties of the first generation AEDs with newer agents to develop a more rational approach for drug selection in older adults. 相似文献
55.
Tuvia Bengal Itzhak Herz Alejandro Solodky Yochai Birnbaum Samuel Sclarovsky Alex Sagie 《Clinical cardiology》1998,21(6):399-404
Background: The correlation between ST elevation in lead V1 during anterior wall acute myocardial infaction (AMI) and the culprit lesion site in the left anterior descending (LAD) coronary artery is poor. Hypothesis: The study was undertaken to assess the electrocardiographic (ECG) characteristics and angiographic significance of ST-segment elevation in lead V1 during anterior wall acute myocardial infarction (AMI). Methods: Data from 115 patients with anterior wall AMI, who underwent coronary angiography within 14 days of hospitalization, were studied. The admission 12-lead ECG was examined and the coronary angiogram was evaluated for the nature of the conal branch of the right coronary artery (RCA) and for the culprit lesion site in the left anterior descending (LAD) coronary artery. Results: Mean ST-segment deviation and the frequency of patients with ST-segment elevation > 0.1 mV were significantly lower in lead V i than in lead V2 (0.136 $$ 0.111 mV vs. 0.421 $$ 0.260 mV, and 37 vs. 96%, for leads Vi and Vi, respectively). A small conal branch not reaching the interventricular septum (IVS) was more prevalent among patients with ST-segnicni elevation >0.1 mV in lead Vi (67%), whereas a large conal branch was more prevalent in patients with ST-segment deviation (1 mV in that lead (83%, p<0.001). No relation was found between ST-segment deviation in lead V i during anterior wall AMI and the culprit lesion site in the LAD. Conclusion: ST-segment elevation in lead V1 during first anterior wall AMI was found in one third of the patients, and its magnitude was lower than that in the other precordial leads. ST-segment elevation in lead V1 favors the presence of a small conal branch of the RCA that does not reach the IVS. 相似文献
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Antonio Bayés de Luna MD PhD Wojciech Zareba MD PhD Miquel Fiol MD PhD Kjell Nikus MD PhD Yochai Birnbaum MD PhD Rafael Baranowski MD PhD Diego Goldwasser MD Paul Kligfield MD PhD Ryszard Piotrowicz MD PhD Günter Breithardt MD PhD Hein Wellens MD PhD 《Annals of noninvasive electrocardiology》2014,19(5):426-441
58.
Yochai Birnbaum Miguel Fiol Kjell Nikus Javier Garcia Niebla Ljuba Bacharova Sergio Dubner Wojciech Zareba Peter W. Macfarlane Antonio Luiz Ribeiro Iwona Cygankiewicz Antoni Bayes de Luna 《Annals of noninvasive electrocardiology》2020,25(5)
The Fourth Universal Definition of Myocardial Infarction (FUDMI) focuses on the distinction between nonischemic myocardial injury and myocardial infarction (MI), along with the role of cardiovascular magnetic resonance, in order to define the etiology of myocardial injury. As a consequence, there is less emphasis on updating the parts of the definition concerning the electrocardiographic (ECG) changes related to MI. Evidence of myocardial ischemia is a prerequisite for the diagnosis of MI, and the ECG is the main available tool for (a) detecting acute ischemia, (b) triage, and (c) risk stratification upon presentation. This review focuses on multiple aspects of ECG interpretation that we firmly believe should be considered for incorporation in any future update to the Universal Definition of MI. 相似文献
59.
Kjell Nikus Yochai Birnbaum Markku Eskola Samuel Sclarovsky Zhan Zhong-qun Olle Pahlm 《Current Cardiology Reviews》2014,10(3):229-236
The electrocardiogram (ECG) findings in acute coronary syndrome should always be interpreted in the context of the clinical findings and symptoms of the patient, when these data are available. It is important to acknowledge the dynamic nature of ECG changes in acute coronary syndrome. The ECG pattern changes over time and may be different if recorded when the patient is symptomatic or after symptoms have resolved. Temporal changes are most striking in cases of ST-elevation myocardial infarction. With the emerging concept of acute reperfusion therapy, the concept ST-elevation/non-ST elevation has replaced the traditional division into Q-wave/non-Q wave in the classification of acute coronary syndrome in the acute phase.
Keypoints:
In acute coronary syndrome, in addition to the traditional electrocardiographic risk markers, such as ST depression, the 12-lead ECG contains additional, important diagnostic and prognostic information. Clinical guidelines need to acknowledge certain high-risk ECG patterns to improve patient care. 相似文献60.
Michael E. Birnbaum Richard Berry Yu-Shan Hsiao Zhenjun Chen Miguel A. Shingu-Vazquez Xiaoling Yu Deepa Waghray Suzanne Fischer James McCluskey Jamie Rossjohn Thomas Walz K. Christopher Garcia 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(49):17576-17581
αβ T-cell receptor (TCR) activation plays a crucial role for T-cell function. However, the TCR itself does not possess signaling domains. Instead, the TCR is noncovalently coupled to a conserved multisubunit signaling apparatus, the CD3 complex, that comprises the CD3εγ, CD3εδ, and CD3ζζ dimers. How antigen ligation by the TCR triggers CD3 activation and what structural role the CD3 extracellular domains (ECDs) play in the assembled TCR–CD3 complex remain unclear. Here, we use two complementary structural approaches to gain insight into the overall organization of the TCR–CD3 complex. Small-angle X-ray scattering of the soluble TCR–CD3εδ complex reveals the CD3εδ ECDs to sit underneath the TCR α-chain. The observed arrangement is consistent with EM images of the entire TCR–CD3 integral membrane complex, in which the CD3εδ and CD3εγ subunits were situated underneath the TCR α-chain and TCR β-chain, respectively. Interestingly, the TCR–CD3 transmembrane complex bound to peptide–MHC is a dimer in which two TCRs project outward from a central core composed of the CD3 ECDs and the TCR and CD3 transmembrane domains. This arrangement suggests a potential ligand-dependent dimerization mechanism for TCR signaling. Collectively, our data advance our understanding of the molecular organization of the TCR–CD3 complex, and provides a conceptual framework for the TCR activation mechanism.T cells are key mediators of the adaptive immune response. Each αβ T cell contains a unique αβ T-cell receptor (TCR), which binds antigens (Ags) displayed by major histocompatibility complexes (MHCs) and MHC-like molecules (1). The TCR serves as a remarkably sensitive driver of cellular function: although TCR ligands typically bind quite weakly (1–200 μM), even a handful of TCR ligands are sufficient to fully activate a T cell (2, 3). The TCR does not possess intracellular signaling domains, uncoupling Ag recognition from T-cell signaling. The TCR is instead noncovalently associated with a multisubunit signaling apparatus, consisting of the CD3εγ and CD3εδ heterodimers and the CD3ζζ homodimer, which collectively form the TCR–CD3 complex (4, 5). The CD3γ/δ/ε subunits each consist of a single extracellular Ig domain and a single immunoreceptor tyrosine-based activation motif (ITAM), whereas CD3ζ has a short extracellular domain (ECD) and three ITAMs (6–11). The TCR–CD3 complex exists in 1:1:1:1 stoichiometry for the αβTCR:CD3εγ:CD3εδ:CD3ζζ dimers (12). Phosphorylation of the intracellular CD3 ITAMs and recruitment of the adaptor Nck lead to T-cell activation, proliferation, and survival (13, 14). Understanding the underlying principles of TCR–CD3 architecture and T-cell signaling is of therapeutic interest. For example, TCR–CD3 is the target of therapeutic antibodies such as the immunosuppressant OKT3 (15), and there is increasing interest in manipulating T cells in an Ag-dependent manner by using naturally occurring and engineered TCRs (16).Assembly of the TCR–CD3 complex is primarily driven by each protein’s transmembrane (TM) region, enforced through the interaction of evolutionarily conserved, charged, residues in each TM region (4, 5, 12). What, if any, role interactions between TCR and CD3 ECDs play in the assembly and function of the complex remains controversial (5): there are several plausible proposed models of activation, which are not necessarily mutually exclusive (5, 17–19). Although structures of TCR–peptide–MHC (pMHC) complexes (2), TCR–MHC-I–like complexes (1), and the CD3 dimers (6–10) have been separately determined, how the αβ TCR associates with the CD3 complex is largely unknown. Here, we use two independent structural approaches to gain an understanding of the TCR–CD3 complex organization and structure. 相似文献