Platelets contribute to COVID-19 clinical manifestations, of which microclotting in the pulmonary vasculature has been a prominent symptom. To investigate the potential diagnostic contributions of ...overall platelet morphology and their α-granules and mitochondria to the understanding of platelet hyperactivation and micro-clotting, we undertook a 3D ultrastructural approach. Because differences might be small, we used the high-contrast, high-resolution technique of focused ion beam scanning EM (FIB-SEM) and employed deep learning computational methods to evaluate nearly 600 individual platelets and 30 000 included organelles within three healthy controls and three severely ill COVID-19 patients. Statistical analysis reveals that the α-granule/mitochondrion-to-plateletvolume ratio is significantly greater in COVID-19 patient platelets indicating a denser packing of organelles, and a more compact platelet. The COVID-19 patient platelets were significantly smaller -by 35% in volume - with most of the difference in organelle packing density being due to decreased platelet size. There was little to no 3D ultrastructural evidence for differential activation of the platelets from COVID-19 patients. Though limited by sample size, our studies suggest that factors outside of the platelets themselves are likely responsible for COVID-19 complications. Our studies show how deep learning 3D methodology can become the gold standard for 3D ultrastructural studies of platelets.
Background Previous intraoperative nerve monitoring (IONM) studies have demonstrated modest-to-no benefit and did not include a nationwide sample of hospitals representative of broad thyroidectomy ...practices. This national study was designed to compare vocal cord paralysis (VCP) rates between thyroidectomy with IONM and without monitoring (conventional). Study Design We performed a retrospective analysis of 243,527 thyroidectomies during 2008 to 2011 using the Nationwide Inpatient Sample. Results Use of IONM increased yearly throughout the study period (2.6% 2008, 5.6% 2009, 6.1% 2010, 6.9% 2011) and during this time, VCP rates in the IONM group initially increased year-over-year (0.9% 2008, 2.4% 2009, 2.5% 2010, 1.4% 2011). In unadjusted analyses, IONM was associated with significantly higher VCP rates (conventional 1.4% vs IONM 1.9%, p < 0.001). After propensity score matching, IONM remained associated with higher VCP rates in partial thyroidectomy and lower VCP rates for total thyroidectomy with neck dissection. Hospital-level analysis revealed that VCP rates were not explained by differential laryngoscopy rates, decreasing the likelihood of ascertainment bias. Additionally, for hospitals in which IONM was applied to more than 50% of thyroidectomies, lower VCP rates were observed (1.1%) compared with hospitals that applied IONM to less than 50% (1.6%, p = 0.016). Higher hospital volume correlated with lower VCP rates in both groups (<75, 75 to 299, >300 thyroidectomies/year: IONM, 2.1%, 1.7%, 1.7%; conventional, 1.5%, 1.3%, 1.0%, respectively). Conclusions According to this study, IONM has not been broadly adopted into practice. Overall, IONM was associated with a higher rate of VCP even after correction for numerous confounders. In particular, low institutional use of IONM and use in partial thyroidectomies are associated with higher rates of VCP. Further studies are warranted to support the broader application of IONM in patients where benefit can be reliably achieved.
Background With increasing use of thyroid ultrasonography, thyroid nodules have been found to be extremely common. For over 25 years, fine needle aspiration (FNA) has been the pivotal diagnostic test ...to discriminate benign from potentially malignant thyroid nodules. Recently, false negative rates exceeding 10% have led to recommendations that thyroid nodules ≥4 cm should be resected regardless of cytology results. Our aim was to determine the false negative rate of FNA cytology on thyroid nodules ≥3 cm interpreted as benign at our institution. Methods A retrospective review was performed at Mayo Clinic from January 2002 through December 2006. Results From 6,921 ultrasonographic-guided thyroid FNAs, 742 were interpreted as benign and ≥3 cm. A definitive histologic diagnosis was available for 145 (20%) patients who underwent thyroidectomy: 1 (0.7%) was false negative. No additional thyroid malignancies were identified in 550 index nodules with average follow-up of 3 years. Conclusion With precise ultrasonographic-guided aspiration, strict adherence to guidelines for adequacy of the sample, proper cytologic preparation, and most importantly, expert cytologic analysis, a diagnosis of benign is extremely reliable for thyroid nodules, regardless of size. Resection for diagnosis is not necessary, and a size ≥3 cm should not be an independent indication for resection.
Objectives This study evaluated the effect of the fellowship interview process in a cohort of general surgery residents. We hypothesized that the interview process would be associated with ...significant clinical time lost, monetary expenses, and increased need for shift coverage. Design An online anonymous survey link was sent via e-mail to general surgery program directors in June 2014. Program directors distributed an additional survey link to current residents in their program who had completed the fellowship interview process. Setting United States allopathic general surgery programs. Participants Overall, 50 general surgery program directors; 72 general surgery residents. Results Program directors reported a fellowship application rate of 74.4%. Residents most frequently attended 8 to 12 interviews (35.2%). Most (57.7%) of residents reported missing 7 or more days of clinical training to attend interviews; these shifts were largely covered by other residents. Most residents (62.3%) spent over $4000 on the interview process. Program directors rated fellowship burden as an average of 6.7 on a 1 to 10 scale of disruption, with 10 being a significant disruption. Most of the residents (57.3%) were in favor of change in the interview process. We identified potential areas for improvement including options for coordinated interviews and improved content on program websites. Conclusions The surgical fellowship match is relatively burdensome to residents and programs alike, and merits critical assessment for potential improvement.
Dissolution and assay of neptunium oxide Xu, N.; Tandon, L.; Gallimore, D. ...
Journal of radioanalytical and nuclear chemistry,
04/2013, Letnik:
296, Številka:
1
Journal Article
Recenzirano
A case study for dissolution and assay of neptunium oxide is presented in this paper. A simple analytical method for completely dissolving neptunium oxide is described. Addition of 12 M HNO
3
is ...sufficient to dissolve neptunium oxide without precipitate formation. Various analytical chemistry methods were evaluated for neptunium assay including controlled potential coulometry, gas proportional counting/alpha spectrometry, gamma spectrometry using a high purity germanium detector, inductively coupled plasma-mass spectrometry, and isotope dilution-inductively coupled plasma-mass spectrometry. The precision and uncertainty of each analytical method is discussed.
Abstract Background Emotional intelligence (EI) has been associated with improved work performance and job satisfaction in several industries. We evaluated whether EI was associated with higher ...measures of work performance and job satisfaction in surgical residents. Methods We distributed the validated Trait EI Questionnaire and job satisfaction survey to all general surgery residents at a single institution in 2015. EI and job satisfaction scores were compared with resident performance using faculty evaluations of clinical competency–based surgical milestones and standardized test scores including the United States Medical Licensing Examination (USMLE) and American Board of Surgery In-Training Examination (ABSITE). Statistical comparison was made using Pearson correlation and simple linear regression adjusting for postgraduate year level. Results The survey response rate was 68.9% with 31 resident participants. Global EI was associated with scores on USMLE Step 2 ( r = 0.46, P = 0.01) and Step 3 ( r = 0.54, P = 0.01) but not ABSITE percentile scores ( r = 0.06, P = 0.77). None of the 16 surgical milestone scores were significantly associated with global EI or EI factors before or after adjustment for postgraduate level. Global EI was associated with overall job satisfaction ( r = 0.37, P = 0.04). Of the facets of job satisfaction, global EI was significantly associated with views of supervision ( r = 0.42, P = 0.02) and nature of work ( r = 0.41, P = 0.02). Conclusions EI was associated with job satisfaction and USMLE performance but not ACGME competency–based milestones or ABSITE scores. EI may be an important factor for fulfillment in surgical training that is not currently captured with traditional in-training performance measures.
Lead is a hazardous substance, making it a disposal and industrial hygiene problem. The potential for creating mixed waste or mixed TRU waste exists if the lead becomes contaminated. The disposal of ...either waste stream is extremely difficult and costly. Bismuth is a non-hazardous material with shielding characteristics similar to lead. An HPGe was characterized using detector shielding composed of lead and polyethylene-based-bismuth to compare the shielding efficacy of both materials. Polymer-bismuth bricks may be recommended as gamma spectrometer shielding for sensitive low-energy measurements.
Simulation and Faculty Development Rogers, David A; Peterson, Dawn Taylor; Ponce, Brent A ...
The Surgical clinics of North America,
08/2015, Letnik:
95, Številka:
4
Journal Article
Recenzirano
As members of the faculty, surgeons take on a variety of roles related to the use of simulation. Surgeons will continue to interact with simulation as learners given the emerging role of simulation ...in continuing medical education. Surgeons who regularly teach others will also be using simulation because of its unique properties as an instructional method. Leading a simulation effort requires vision, creativity in resource management, and team leadership skills. Surgeons can use simulation to innovate in surgical patient care and in surgical education.
A variety of unique radioactive samples have been measured recently at Los Alamos National Laboratory (LANL) using an electrically-cooled high-purity germanium detector. In each case the purpose of ...the measurements included one or more of the following objectives: (1) an accurate determination of the isotopic weight fractions of different plutonium or uranium materials; (2) an accurate determination of the isotopic quantity in the absence of relevant calibration standards; and (3) a qualitative determination of various sample impurities for additional forensic information. This paper discusses how simple modifications to the PC-FRAM parameter sets enabled a better determination of the isotopic content of the following samples: (1) high-purity plutonium metal, (2) plutonium-beryllium (PuBe) neutron sources, (3) neutron-irradiated natural uranium, and (4) re-processed HEU fuel with elevated
236
U content. The isotopic quantity in a variety of samples was determined using a combination of the Spectral Nondestructive Assay Platform (SNAP™) routine from Eberline Services and the Monte Carlo Neutral Particle (MCNP) code developed at LANL. The non-traditional sources that were quantified with these gamma ray modeling codes included dozens of neutron-irradiated targets of natural uranium, several plutonium-beryllium neutron sources, and three high-purity samples of plutonium metal.
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