209 research outputs found
Mathematical modeling and experimental validation of the spatial distribution of boron in the root of arabidopsis thaliana identify high boron accumulation in the tip and predict a distinct root tip uptake function
Boron, an essential micronutrient, is transported in roots of Arabidopsis thaliana mainly by two different types of transporters, BORs and NIPs (nodulin26-like intrinsic proteins). Both are plasma membrane localized, but have distinct transport properties and patterns of cell type-specific accumulation with different polar localizations, which are likely to affect boron distribution. Here, we used mathematical modeling and an experimental determination to address boron distributions in the root. A computational model of the root is created at the cellular level, describing the boron transporters as observed experimentally. Boron is allowed to diffuse into roots, in cells and cell walls, and to be transported over plasma membranes, reflecting the properties of the different transporters. The model predicts that a region around the quiescent center has a higher concentration of soluble boron than other portions. To evaluate this prediction experimentally, we determined the boron distribution in roots using laser ablation-inductivity coupled plasma-mass spectrometry. The analysis indicated that the boron concentration is highest near the tip and is lower in the more proximal region of the meristem zone, similar to the pattern of soluble boron distribution predicted by the model. Our model also predicts that upward boron flux does not continuously increase from the root tip toward the mature region, indicating that boron taken up in the root tip is not efficiently transported to shoots. This suggests that root tip-absorbed boron is probably used for local root growth, and that instead it is the more mature root regions which have a greater role in transporting boron toward the shoots
Treatment of wounds colonized by multidrug resistant organisms in immune-compromised patients: a retrospective case series.
Immune-compromised patients incur a high risk of surgical wound dehiscence and colonization by multidrug resistant organisms. Common treatment has been debridement and spontaneous secondary healing.All immune-compromised patients referred to our Institution between March 1, 2010 and November 30, 2011 for dehiscent abdominal wounds growing multidrug resistant organisms were treated by serial wound debridements and negative pressure dressing. They were primarily closed, despite positive microbiological cultures, when clinical appearance was satisfactory.Nine patients were treated by direct wound closure, five had been treated previously by secondary intention healing.According to our results, fast healing can be safely obtained by closure of a clinically healthy wound, despite growth of multidrug resistant organisms, even in immune-compromised patients
Immune-inflammatory and clinicopathologic prognostic factors in a Western cohort of resected gastric cancers (GCs)
A user-friendly nomogram to predict relapse-free survival (RFS) in western patients with resected gastric cancer (GC)
Reproducibility of acute pulmonary vein isolation guided by the ablation index.
BACKGROUND: Atrial fibrillation (AF) ablation outcome is still operator dependent. Ablation Index (AI) is a new lesion quality marker that has been demonstrated to allow acute durable pulmonary vein (PV) isolation followed by a high single-procedure arrhythmia-free survival. This prospective, multicenter study was designed to evaluate the reproducibility of acute PV isolation guided by the AI. METHODS: A total of 490 consecutive patients with paroxysmal (80.4%) and persistent AF underwent first time PV encircling and were divided in four study groups according to operator preference in choosing the ablation catheter (a contact force [ST] or contact force surround flow [STSF] catheter) and the AI setting (330 at posterior and 450 at anterior wall or 380 at posterior and 500 at anterior wall). Radiofrequency was delivered targeting interlesion distance ≤6 mm. RESULTS: The rate of first-pass PV isolation (ST330 90 ± 16%, ST380 87 ± 19%, STSF330 90 ± 17%, STSF380 91 ± 15%, P = .585) was similar among the four study groups, whereas procedure (ST330 129 ± 44 minutes, ST380 144 ± 44 minutes, STSF330 120 ± 72 minutes, STSF380 125 ± 73 minutes, P < .001) and fluoroscopy time (ST330 542 ± 285 seconds, ST380 540 ± 416 seconds, STSF330 257 ± 356 seconds, STSF380 379 ± 454 seconds, P < 0.001) significantly differed. The difference in the rate of first-pass isolation was not statistical different (P = .06) among the 12 operators that performed at least 15 procedures. CONCLUSIONS: An ablation protocol respecting strict criteria for contiguity and quality lesion results in high and comparable rate of acute PV isolation among operator performing ablation with different catheters, AI settings, procedure, and fluoroscopy times
Multicentre validation of an immune-inflammation-based nomogram to predict survival in western resectable gastroesophageal adenocarcinoma: The NOMOGAST
Development and Multicenter Validation of a Novel Immune-Inflammation-Based Nomogram to Predict Survival in Western Resectable Gastric and Gastroesophageal Junction Adenocarcinoma (GEA): The NOMOGAST
Background. More than 50% of operable GEA relapse after curative-intent resection. We aimed at externally validating a nomogram to enable a more accurate estimate of individualized risk in resected GEA. Methods. Medical records of a training cohort (TC) and a validation cohort (VC) of patients undergoing radical surgery for c/uT2-T4 and/or node-positive GEA were retrieved, and potentially interesting variables were collected. Cox proportional hazards in univariate and multivariate regressions were used to assess the effects of the prognostic factors on OS. A graphical nomogram was constructed using R software’s package Regression Modeling Strategies (ver. 5.0-1). The performance of the prognostic model was evaluated and validated. Results. The TC and VC consisted of 185 and 151 patients. ECOG:PS > 0 (p < 0.001), angioinvasion (p < 0.001), log (Neutrophil/Lymphocyte ratio) (p < 0.001), and nodal status (p = 0.016) were independent prognostic values in the TC. They were used for the construction of a nomogram estimating 3- and 5-year OS. The discriminatory ability of the model was evaluated with the c-Harrell index. A 3-tier scoring system was developed through a linear predictor grouped by 25 and 75 percentiles, strengthening the model’s good discrimination (p < 0.001). A calibration plot demonstrated a concordance between the predicted and actual survival in the TC and VC. A decision curve analysis was plotted that depicted the nomogram’s clinical utility. Conclusions. We externally validated a prognostic nomogram to predict OS in a joint independent cohort of resectable GEA; the NOMOGAST could represent a valuable tool in assisting decision-making. This tool incorporates readily available and inexpensive patient and disease characteristics as well as immune-inflammatory determinants. It is accurate, generalizable, and clinically effectivex
Reproducibility of pulmonary vein isolation guided by the ablation index: 1-year outcome of the AIR registry
Measurement of the atmospheric muon flux with the NEMO Phase-1 detector
The NEMO Collaboration installed and operated an underwater detector
including prototypes of the critical elements of a possible underwater km3
neutrino telescope: a four-floor tower (called Mini-Tower) and a Junction Box.
The detector was developed to test some of the main systems of the km3
detector, including the data transmission, the power distribution, the timing
calibration and the acoustic positioning systems as well as to verify the
capabilities of a single tridimensional detection structure to reconstruct muon
tracks. We present results of the analysis of the data collected with the NEMO
Mini-Tower. The position of photomultiplier tubes (PMTs) is determined through
the acoustic position system. Signals detected with PMTs are used to
reconstruct the tracks of atmospheric muons. The angular distribution of
atmospheric muons was measured and results compared with Monte Carlo
simulations.Comment: Astrop. Phys., accepte
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