126 research outputs found
Water Towers, Pump Houses, and Mountain Streams: Students' Ideas about Watersheds
This study investigates students' ideas about watersheds and how these ideas change across grade level. A group of 95 students were each asked to draw a picture of a watershed and explain their drawings. The results revealed that, in general, students understand the concept of watersheds from a very limited scientific perspective. Sixth and some seventh grade students envisioned watersheds as a water storage facility or a facility that supplies water. Eighth and ninth grade students' ideas about a watershed focused on a mountainous stream. Older students also incorporated the hydrologic cycle, but rarely represented linkages between land and watercourses. For all students, humans do not appear to be a part of a watershed, but separate from it. Educational levels: Graduate or professional
The need for structured thoracic robotic training: the perspective of an American Association for Thoracic Surgery surgical robotic fellow
Since the initial experiences with robotic platforms in
thoracic surgery (1), the number of procedures performed
with this technique have continued to increase (2). Not
only have newer trainees demonstrated interest in the field,
but former open and VATS surgeons have also become
aware of the advantages that the robotic platform provides
(1,3). However, although some authors have implemented
robotic thoracic surgery safely (4,5) others still consider it
inefficient, citing the increased operative time (related to
the learning curve), the initial instrument cost, and the lack
of appropriate directed training (3)
Relationship between margin distance and local recurrence among patients undergoing wedge resection for small (â€2 cm) nonâsmall cell lung cancer
ObjectiveSuccessful pulmonary wedge resection for early-stage nonâsmall cell lung cancer requires a pathologically confirmed negative margin. To date, however, no clear evidence is available regarding whether an optimal margin distance, defined as the distance from the primary tumor to the closest resection margin, exists. Toward addressing this gap, we investigated the relationship between the margin distance and local recurrence risk.MethodsWe reviewed all adult patients who had undergone wedge resection for small (â€2 cm) nonâsmall cell lung cancer from January 2001 to August 2011, with follow-up through to December 31, 2011. The exclusion criteria included other active noncutaneous malignancies, bronchoalveolar carcinomas, lymph node or distant metastases at diagnosis, large cell cancer, adenosquamous cancer, multiple, multifocal, and/or metastatic disease, and previous chemotherapy or radiotherapy. Using Cox regression analysis, we examined the relationship between the margin distance and interval to local recurrence, adjusting for chronic obstructive pulmonary disease, forced expiratory volume in 1 second, smoking, diabetes, tumor size, tumor location, surgeon, open versus video-assisted thoracoscopic surgery, and whether the lymph nodes were sampled.ResultsOf 557 consecutive adult patients, 479 met our inclusion criteria. The overall, unadjusted 1- and 2-year local recurrences rate was 5.7% and 11.0%, respectively. From the adjusted analyses, an increased margin distance was significantly associated with a lower risk of local recurrence (P = .033). Patients with a 10-mm margin distance had a 45% lower local recurrence risk than those with a 5-mm distance (hazard ratio, 0.55; 95% confidence interval, 0.35-0.86). Beyond 15 mm, no evidence of additional benefit was associated with an increased margin distance.ConclusionsIn wedge resection for small nonâsmall cell lung cancer, increasing the margin distance â€15 mm significantly decreased the local recurrence risk, with no evidence of additional benefit beyond 15 mm
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Low Incidence of Chest Wall Pain with a Risk-Adapted Lung Stereotactic Body Radiation Therapy Approach Using Three or Five Fractions Based on Chest Wall Dosimetry
Purpose To examine the frequency and potential of dose-volume predictors for chest wall (CW) toxicity (pain and/or rib fracture) for patients receiving lung stereotactic body radiotherapy (SBRT) using treatment planning methods to minimize CW dose and a risk-adapted fractionation scheme. Methods: We reviewed data from 72 treatment plans, from 69 lung SBRT patients with at least one year of follow-up or CW toxicity, who were treated at our center between 2010 and 2013. Treatment plans were optimized to reduce CW dose and patients received a risk-adapted fractionation of 18 GyĂ3 fractions (54 Gy total) if the CW V30 was less than 30 mL or 10â12 GyĂ5 fractions (50â60 Gy total) otherwise. The association between CW toxicity and patient characteristics, treatment parameters and dose metrics, including biologically equivalent dose, were analyzed using logistic regression. Results: With a median follow-up of 20 months, 6 (8.3%) patients developed CW pain including three (4.2%) grade 1, two (2.8%) grade 2 and one (1.4%) grade 3. Five (6.9%) patients developed rib fractures, one of which was symptomatic. No significant associations between CW toxicity and patient and dosimetric variables were identified on univariate nor multivariate analysis. Conclusions: Optimization of treatment plans to reduce CW dose and a risk-adapted fractionation strategy of three or five fractions based on the CW V30 resulted in a low incidence of CW toxicity. Under these conditions, none of the patient characteristics or dose metrics we examined appeared to be predictive of CW pain
Enzymatic synthesis of chlorogenic acid glucoside using dextransucrase and its physical and functional properties
Chlorogenic acid, a major polyphenol in edible plants, possesses strong antioxidant activity, anti-lipid peroxidation and anticancer effects. It used for industrial applications; however, this is limited by its instability to heat or light. In this study, we, for the first time synthesized chlorogenic acid glucoside (CHG) via transglycosylation using dextransucrase from Leuconostoc mesenteroides and sucrose. CHG was purified and its structure determined by nuclear magnetic resonance and matrix-associated laser desorption ionizationâtime-of-flight mass spectroscopy. The production yield of CHG was 44.0% or 141 mM, as determined by response surface methodology. CHG possessed a 65% increase in water solubility and a 2-fold browning resistance and it displayed stronger inhibition of lipid peroxidation and of colon cancer cell growth by MTT assay, compared to chlorogenic acid. Therefore, this study may expand the industrial applications of chlorogenic acid as water-soluble or browning resistant compound (CHG) through enzymatic glycosylation
IFI27 transcription is an early predictor for COVID-19 outcomes, a multi-cohort observational study
PurposeRobust biomarkers that predict disease outcomes amongst COVID-19 patients are necessary for both patient triage and resource prioritisation. Numerous candidate biomarkers have been proposed for COVID-19. However, at present, there is no consensus on the best diagnostic approach to predict outcomes in infected patients. Moreover, it is not clear whether such tools would apply to other potentially pandemic pathogens and therefore of use as stockpile for future pandemic preparedness.MethodsWe conducted a multi-cohort observational study to investigate the biology and the prognostic role of interferon alpha-inducible protein 27 (IFI27) in COVID-19 patients.ResultsWe show that IFI27 is expressed in the respiratory tract of COVID-19 patients and elevated IFI27 expression in the lower respiratory tract is associated with the presence of a high viral load. We further demonstrate that the systemic host response, as measured by blood IFI27 expression, is associated with COVID-19 infection. For clinical outcome prediction (e.g., respiratory failure), IFI27 expression displays a high sensitivity (0.95) and specificity (0.83), outperforming other known predictors of COVID-19 outcomes. Furthermore, IFI27 is upregulated in the blood of infected patients in response to other respiratory viruses. For example, in the pandemic H1N1/09 influenza virus infection, IFI27-like genes were highly upregulated in the blood samples of severely infected patients.ConclusionThese data suggest that prognostic biomarkers targeting the family of IFI27 genes could potentially supplement conventional diagnostic tools in future virus pandemics, independent of whether such pandemics are caused by a coronavirus, an influenza virus or another as yet-to-be discovered respiratory virus
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