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The practice of contrast-enhanced magnetic resonance angiography (CEMRA) has changed significantly in the span of a decade. Concerns regarding gadolinium (Gd)-associated nephrogenic systemic fibrosis in those with severely impaired renal function spurred developments in low-dose CEMRA and non-contrast MRA as well as efforts to seek alternative MR contrast agents. Originally developed for MR imaging use, ferumoxytol (an ultra-small superparamagnetic iron oxide nanoparticle), is currently approved by the US Food and Drug Administration for the treatment of iron deficiency anaemia in adults with renal disease. Since its clinical availability in 2009, there has been rising interest in the scientific and clinical use of ferumoxytol as an MR contrast agent. The unique physicochemical and pharmacokinetic properties of ferumoxytol, including its long intravascular half-life and high r1 relaxivity, support a spectrum of MRI applications beyond the scope of Gd-based contrast agents. Moreover, whereas Gd is not found in biological systems, iron is essential for normal metabolism, and nutritional iron deficiency poses major public health challenges worldwide. Once the carbohydrate shell of ferumoxytol is degraded, the elemental iron at its core is incorporated into the reticuloendothelial system. These considerations position ferumoxytol as a potential game changer in the field of CEMRA and MRI. In this paper, we aim to summarise our experience with the cardiovascular applications of ferumoxytol and provide a brief synopsis of ongoing investigations on ferumoxytol-enhanced MR applications.

A Vietnamese domestic plant namely Solanum nigrum (S. nigrum) was subjected to test for larvicidal activity on two majors Dengue hemorrhagic fever (DHF) vectors Aedes aegypti (Ae. aegypti) and Aedes albopictus (Ae. albopictus). The plant was processed to get infusions in hot water or extracted in ethanol. Laboratory and field larval strains of two Aedes species were exposed to the infusions and extract at increasing concentrations for one hour and followed-up intensively for up to 72 hours. The obtained results of bioassay showed larvicidal effects of extract on all mosquito strains. The effects on laboratory strain of Ae. aegypti larvae were correlated with infusions and extract concentrations. Chopped plant infusions in hot water indicated mortality up to 77.3% of larvae. Ground plant infusions killed all of exposed larvae at day 3 postexposure. Median lethal concentrations (LC50,s) of chopped and ground plant infusions were 10.25 and 7.54%, respectively. Ethanolic extract had very strong effect on experimental subjects. Within 72 hours, 100% of laboratory strain of Ae. aegypti larvae died after exposure to extract at 100 parts per million (ppm) or higher concentrations. Ethanolic plant extract showed similar larvicidal effect on field strains of Ae. aegypti and Ae. albopictus. The percentage mortality of field strains larvae reached 100% after exposure to 100 ppm of plant extract. At concentrations of 1000 ppm, 100% of exposed larvae died with 8 hours. LC50 on tested larvae was 25.07-33.60 ppm. Strong larvicidal activity of S. nigrum suggests the possible application in DHF vector control effort. [ABSTRACT FROM AUTHOR]

Coupled slope and scintillation detection and ranging (CO-SLIDAR) is a very promising technique for the metrology of near ground C n 2 profiles. It exploits both phase and scintillation measurements obtained with a dedicated wavefront sensor and allows profiling on the full line of sight between pupil and sources. This technique is applied to an associated instrument based on a mid-IR Shack-Hartmann wavefront sensor coupled to a 0.35 m telescope, which observes two cooperative sources. This paper presents what we believe is the first comprehensive description of the CO-SLIDAR method in the context of near-ground optical turbulence metrology. It includes the presentation of the physics principles underlying the measurements of our unsupervised C n 2 profile reconstruction strategy together with the error bar estimation on the reconstructed values. The application to data acquired in a heterogeneous rural landscape during an experimental campaign in Lannemezan, France, demonstrates the ability to obtain profiles with a sampling pitch of about 220 m over a 2.7 km line of sight. The retrieved C n 2 profiles are presented and their variability in space and time is discussed.

Background: Vineyard workers (VW) are exposed to various respiratory allergens. The aims of the study were to determine the prevalence of work related respiratory symptoms (WRS) in Champagne VW in France and to analyze the relationships between symptoms, occupational exposure and sensitization profile., Methods: VW of Reims area were prospectively recruited between 2007 and 2010. Demographic and occupational characteristics were recorded. Respiratory symptoms were scored for each month of the past year. Results of respiratory functional tests and skin prick tests for common respiratory allergens, grape moulds and vine pollen were recorded., Results: 307 subjects were included. The prevalence of WRS was 11%. Compared to subjects with symptoms unrelated to work, subjects with WRS were more frequently sensitized to gramineae (34% vs 18%, p = 0.05), described ocular itching (74% vs 37%, p < 0.001) and seasonal symptoms (88% vs 69%, p = 0.03) mainly during lifting and trellising (57% vs 17%, p < 0.001)., Conclusion: WRS are frequent in Champagne WV and are associated with a sensitization to gramineae and with activities performed close to vine in late spring.

Helical multi-wire cables are widely used in bridges (suspended or prestressed) and anchored retaining wall constructions. Such structures can be damaged or degraded due to corrosion and fatigue. Non destructive evaluation techniques are required to reveal defects inside cable structures. Among these numerous techniques, elastic guided waves are of potential interest owing to their ability to propagate over long distances. However in civil engineering, cables are often buried or grouted in large solid media that can be considered as unbounded. Waves can strongly attenuate along the guide axis due to the energy leakage into the surrounding medium, which reduces the propagating distance. This energy leakage can be enhanced in helical structures, which further complicates their inspection. Searching modes with low attenuation becomes necessary. The goal of this work is to propose a numerical approach to compute modes in embedded helical structures, combining the so-called semi analytical finite element method and a radial perfectly matched layer technique. Two types of radial perfectly matched layer, centered and off-centered, are considered. Both are implemented in a twisting coordinate system which preserves translational invariance. The centered configuration is validated thanks to the twisted cylinder test case. The effect of twist on the eigenspectrum is briefly discussed. Then, an embedded helical wire of circular cross-section is considered. The off-centered configuration is shown to give the same results as the centered one. The effect of twist on modal attenuation is investigated. Finally, computations are performed for a seven-wire strand embedded into concrete, widely used in civil engineering cables., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The steps of the standard method to determine soluble aluminium concentration are filtering, followed by acidifying, then analysing with the atomic absorption spectrophotometer (AAS). When applied to alkaline humic water, acidification gives rise to the formation of humic acid as a brown particulate matter. Of the total soluble aluminium in the original water, 49-61% forms complexes with the particulate humic acid upon acidification. Although the AAS is capable of detecting the binding aluminium, the particulate nature of humic acid easily induces inaccurate readings as a result of the non-uniform distribution of the particulate matter. A more precise analysis of soluble aluminium concentration of alkaline humic water is shown to be achievable in basicified solutions instead. Basicified solutions keep humic acid in the soluble form; hence maintain the homogeneity of the sample.

In patients with type I diabetes mellitus, clinical studies have demonstrated decreased secretion of pancreatic juice by the pancreatic excretory duct system. The cause of this decrease is unknown, but could involve changes in initial signal transduction pathways or one or more of the electrolyte transport components that subserve regulated fluid secretion. We have compared responsiveness to secretin in pancreatic ducts isolated from healthy and diabetic Hartley guinea pigs and also have compared the expression of CFTR and Na+, K(+)-ATPase in these two groups, as the activities of these two proteins are essential for secretion of pancreatic juice. The increases in cyclic AMP levels evoked by exposure to either 0.1 nM or 0.1 microM secretin were not significantly different in pancreatic ducts isolated from healthy and diabetic guinea pigs nor were levels of CFTR or Na+, K(+)-ATPase expression. By contrast, Na+, K(+)-ATPase activity in pancreatic ducts isolated from diabetic guinea pigs was decreased by 70%, suggesting a change in the enzyme's catalytic properties in the diabetic tissues. The observed decrease would be expected to seriously compromise the production of pancreatic juice.

Background: The diagnosis of chronic sinusitis is dependent on the radiographic evidence of sinus disease., Methods: We evaluated the performance of radiographs and computed tomographic (CT) scans for the examination of the paranasal sinuses of 91 patients of both sexes, ranging in age from 2 to 17 years, who had chronic upper respiratory tract symptoms for at least 3 months. The CT scan findings were categorized as no disease; minimal disease, and mild, moderate, and severe sinusitis., Results: Fifty-eight patients (63%) had chronic sinusitis: CT scan abnormalities were minimal in 17%, mild in 19%, moderate in 21%, and severe in 43%. There was a statistically significant correlation between rhinorrhea (r = 0.25, p = 0.01), cough (r = 0.27, p = 0.009), and the severity of sinus abnormality as determined by CT scan. Clinical presentation in the mild, moderate, and severe sinusitis groups (p < 0.05) was significantly different from that of the no disease group, whereas the minimal disease group had subclinical presentation (p = 0.11). Clinically significant chronic sinusitis often occurred at multiple sites: 44% of patients had pansinusitis, 50% had disease involvement of at least two sinuses, and 6% had disease in a single sinus. When sinus radiographs were compared with CT scans (n = 70 cases), radiographs could not identify minimal disease. For clinically significant sinusitis, sinus radiographs detected disease in 1 of 5 (20%) frontal sinuses, 0 of 12 (0%) sphenoidal sinuses, and 17 of 31 (54%) ethmoidal sinuses. With the minimal criteria of 40% to 50% opacification or fluid level filling of the maxillary antrum, radiographs detected disease in 37 of 49 (75%) cases. The sensitivity and specificity for a Waters view to confirm clinically significant chronic sinusitis without specifying the sites and severity were acceptable at 76% and 81%, respectively. When limited sinus CT scans were compared with full CT evaluation (n = 49 cases), limited studies detected 5 of 5 (100%) frontal, 9 of 11 (82%) sphenoidal, 14 of 19 (73%) ethmoidal, and 39 of 40 (97%) cases of maxillary sinusitis. The overall agreement was 88%., Conclusions: A single Waters view is an acceptable part of the initial evaluation of pediatric chronic sinusitis; however, a limited CT scan is a better alternative.

We examined the prevalence of chronic sinusitis among children who presented to allergy clinics with chronic (> or = 3 months) respiratory symptoms. Ninety-one patients, ranging from 2 to 17 years of age with 62% male and 72% white, completed the study. Fifty-nine percent of patients had positive skin test results, and 25.3% had chronic asthma. Paranasal sinuses were examined by coronal sinus computed tomographic scan. Sixty-three percent (58 to 91) had chronic sinusitis, 5.5% (5 of 91) had concha bullosa, 1% (1 of 91) had foreign body, and 19% (19 of 91) had deviated nasal septums. Among symptoms of sneezing, nasal congestion, postnasal drip, coughing, wheezing, rhinorrhea, and headache, no single symptom was an acceptable predictor of abnormality on computed tomographic scan examinations. Combining the symptoms of moderate to severe rhinorrhea and cough with minimum sneezing had a specificity of 95% and a sensitivity of 38% in predicting the presence of chronic sinusitis. Allergic rhinitis (p = 0.27), mild deviated nasal septum (p = 0.11), unobstructive concha bullosa (p = 0.13), and passive exposure to cigarette smoke (p = 0.53) were not risk factors associated with sinus abnormalities. Age (r = 0.30, p = 0.004) in pediatric patients with chronic respiratory symptoms was the single risk factor significantly associated with abnormalities on sinus computed tomographic scan. Seventy-three percent of children 2 to 6 years of age, 74% of children 6 to 10 years of age, and 38% of children older than 10 had chronic sinusitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Basophils from approximately one fifth of the population were found to be unresponsive (nonreleasers), in terms of both histamine and leukotriene release, to an IgE cross-linking stimulus, such as anti-IgE antibody. Although unresponsive to any IgE-mediated stimulation, these basophils responded to non-IgE-mediated stimuli, such as the phorbol ester, 12-o-tetradecanoyl phorbol-13 acetate, the calcium ionophore, A23187, and to formyl-methionyl-leucyl-phenylalanine peptide. These stimuli produced equal dose-response curves in both releaser (basophils able to respond with greater than 5% histamine release to anti-IgE antibody) and nonreleaser basophils. Nonreleaser basophils possessed statistically similar densities of cell-surface IgE antibody (287,000 versus 400,000 IgE molecules per basophil for releaser and nonreleaser basophils, respectively), and with 12-o-tetradecanoyl phorbol-13 acetate as a probe of anti-IgE-induced cross-linking, the IgE on nonreleaser basophils was found to be cross-linked by the polyclonal anti-IgE antibody used for these studies. Interleukin-3 (IL-3) has previously been demonstrated to enhance markedly both histamine and leukotriene release in human basophils. However, IL-3 was unable to convert nonreleasing basophils into releasing basophils, as measured by anti-IgE antibody. IL-3 equivalently enhanced formyl methionine peptide-induced release in both releaser and nonreleaser basophils, suggesting that the lack of an effect on anti-IgE-induced release was not due to a lack of IL-3 receptors. Although there are several possible interpretations of these data, these results and results of our previous studies of protein kinase C activation and cytosolic Ca++ elevations in human basophils suggest that nonreleasing basophils have a defect in early signal transduction, possibly involving the influx of Ca++.