616 research outputs found
Experience with impacted upper ureteral Stones; should we abandon using semirigid ureteroscopes and pneumatic lithoclast?
<p>Abstract</p> <p>Introduction</p> <p>The AUA/EAU Ureteral Stones Guideline Panel reported that the stone free rate for the proximal ureteral stones is around 81% when treated by either SWL or ureteroscopy (URS).</p> <p>Complication rates, most notably ureteral perforation and long-term complications of URS such as stricture formation rates, have been reduced to < 5%. Moreover, impacted ureteral calculi are more difficult to fragment with SWL because of the lack of natural expansion space for stones, this result in a situation that is better managed by ureteroscopy. The aim of this study is to assess the efficacy, safety, and complications of impacted upper ureteral stone disintegration using semirigid ureteroscopes and pneumatic lithotripsy.</p> <p>Methods</p> <p>We retrospectively analyzed the records of 267 consecutive patients with impacted upper ureteral stones (9–20 mm) who were treated by semirigid ureteroscopes and pneumatic disintegration. The efficacy of treatment was estimated using the stone-free rate and all treatment related complications were analyzed.</p> <p>Results</p> <p>Except for 24 cases where the stone migrated to the kidney, the stone was successfully treated ureteroscopically, with a low rate of minimal complications such as mild hematuria (18.4%), short term low grade fever (13.5%). Only 3 patients (1.1%) had high grade fever and none had post operative stricture.</p> <p>Conclusion</p> <p>The use of semirigid URS and pneumatic lithotripsy in impacted upper ureteral stones in experienced hands has very satisfactory results with minimal complications. When Holmium laser and flexible URS are not available, semirigid URS and pneumatic lithotripsy is a good alternative that shouldn't, yet, be abandoned.</p
A microwave-based technique to determine saccharides and polyols contents in Spirulina (Arthrospira platensis)
The growing demand for Spirulina (Arthrospira platensis) as a dietary supplement suggests that a rapid and reliable method to determine its saccharides and polyols content would be of great interest. Additionally, the impact of these microalga growing conditions may have on such content would be really useful for Spirulina producers. This manuscript presents the development and validation of a new analytical microwave-assisted extraction (MAE) method as the first step in determining saccharides and polyols in spirulina samples. A Box Behnken design has been employed to evaluate three extraction variables, viz., temperature (x(1): 30, 55 and 80 degrees C), solvent composition (x(2): 0, 25, and 50% ethanol in water), and solvent to sample ratio (x(3): 10:1, 20:1, and 30:1 mL of solvent per g of sample). These extraction variables have been optimized by Response Surface Methodology (RSM). Under the optimal conditions that have been thereby established (i.e., 30 degrees C, 50% ethanol in water, and 30:1 solvent to sample ratio), a kinetic study has been performed with full recovery in 15 min. Subsequently, the developed MAE method was validated by determining the number of parameters, including linearity, LODs, LOQs, accuracy, and precision. Finally, the resulting MAE method was successfully applied to determine saccharides and polyols contents in a number of Spirulina samples that had been cultivated in varying salinity media. Five saccharides and polyols were identified in Spirulina, i.e., inositol, glycerol, sorbitol, glucose, and maltose. The total amount of the compounds of interest in the Spirulina that had been cultivated in a higher salinity media (17 and 25 g L-1 of sodium chloride in water) was six-folds higher than the one cultivated in low saline water (0 and 3 g L-1 of sodium chloride in water). This substantial content difference was mainly explained by the considerable increment in glycerol and glucose contents when grown in a more saline medium. Therefore, it has been demonstrated that the new method is suitable to determine saccharides and polyols contents in different Spirulina samples. (C) 2021 The Author(s). Published by Elsevier B.V
Effects of intranasal TNFα on granulocyte recruitment and activity in healthy subjects and patients with allergic rhinitis
<p>Abstract</p> <p>Background</p> <p>TNFα may contribute to the pathophysiology of airway inflammation. For example, we have recently shown that nasal administration of TNFα produces late phase co-appearance of granulocyte and plasma exudation markers on the mucosal surface. The objective of the present study was to examine indices of granulocyte presence and activity in response to intranasal TNFα challenge.</p> <p>Methods</p> <p>Healthy subjects and patients with allergic rhinitis (examined out of season) were subjected to nasal challenge with TNFα (10 μg) in a sham-controlled and crossover design. Nasal lavages were carried out prior to and 24 hours post challenge. Nasal biopsies were obtained post challenge. Nasal lavage fluid levels of myeloperoxidase (MPO) and eosinophil cationic protein (ECP) were analyzed as indices of neutrophil and eosinophil activity. Moreover, IL-8 and α<sub>2</sub>-macroglobulin were analyzed as markers of pro-inflammatory cytokine production and plasma exudation. Nasal biopsy numbers of neutrophils and eosinophils were monitored.</p> <p>Results</p> <p>Nasal lavage fluid levels of MPO recorded 24 hours post TNFα challenge were increased in healthy subjects (p = 0.0081) and in patients with allergic rhinitis (p = 0.0081) (<it>c.f</it>. sham challenge). Similarly, α<sub>2</sub>-macroglobulin was increased in healthy subjects (p = 0.014) and in patients with allergic rhinitis (p = 0.0034). Lavage fluid levels of ECP and IL-8 were not affected by TNFα challenge. TNFα increased the numbers of subepithelial neutrophils (p = 0.0021), but not the numbers of eosinophils.</p> <p>Conclusion</p> <p>TNFα produces a nasal inflammatory response in humans that is characterised by late phase (i.e., 24 hours post challenge) neutrophil activity and plasma exudation.</p
Theory and phenomenology of two-Higgs-doublet models
We discuss theoretical and phenomenological aspects of two-Higgs-doublet
extensions of the Standard Model. In general, these extensions have scalar
mediated flavour changing neutral currents which are strongly constrained by
experiment. Various strategies are discussed to control these flavour changing
scalar currents and their phenomenological consequences are analysed. In
particular, scenarios with natural flavour conservation are investigated,
including the so-called type I and type II models as well as lepton-specific
and inert models. Type III models are then discussed, where scalar flavour
changing neutral currents are present at tree level, but are suppressed by
either specific ansatze for the Yukawa couplings or by the introduction of
family symmetries. We also consider the phenomenology of charged scalars in
these models. Next we turn to the role of symmetries in the scalar sector. We
discuss the six symmetry-constrained scalar potentials and their extension into
the fermion sector. The vacuum structure of the scalar potential is analysed,
including a study of the vacuum stability conditions on the potential and its
renormalization-group improvement. The stability of the tree level minimum of
the scalar potential in connection with electric charge conservation and its
behaviour under CP is analysed. The question of CP violation is addressed in
detail, including the cases of explicit CP violation and spontaneous CP
violation. We present a detailed study of weak basis invariants which are odd
under CP. A careful study of spontaneous CP violation is presented, including
an analysis of the conditions which have to be satisfied in order for a vacuum
to violate CP. We present minimal models of CP violation where the vacuum phase
is sufficient to generate a complex CKM matrix, which is at present a
requirement for any realistic model of spontaneous CP violation.Comment: v3: 180 pages, 506 references, new chapter 7 with recent LHC results;
referee comments taken into account; submitted to Physics Report
Spry1 Is Expressed in Hemangioblasts and Negatively Regulates Primitive Hematopoiesis and Endothelial Cell Function
Development of the hematopoietic and endothelial lineages derives from a common mesodermal precursor, the Flk1(+) hemangioblast. However, the signaling pathways that regulate the development of hematopoietic and endothelial cells from this common progenitor cell remains incompletely understood. Using mouse models with a conditional Spry1 transgene, and a Spry1 knockout mouse, we investigated the role of Spry1 in the development of the endothelial and hematopoietic lineages during development.Quantitative RT-PCR analysis demonstrates that Spry1, Spry2, and Spry4 are expressed in Flk1(+) hemangioblasts in vivo, and decline significantly in c-Kit(+) and CD41(+) hematopoietic progenitors, while expression is maintained in developing endothelial cells. Tie2-Cre-mediated over-expression of Spry1 results in embryonic lethality. At E9.5 Spry1;Tie2-Cre embryos show near normal endothelial cell development and vessel patterning but have reduced hematopoiesis. FACS analysis shows a reduction of primitive hematopoietic progenitors and erythroblastic cells in Spry1;Tie2-Cre embryos compared to controls. Colony forming assays confirm the hematopoietic defects in Spry1;Tie2-Cre transgenic embryos. Immunostaining shows a significant reduction of CD41 or CD71 and dpERK co-stained cells in Spry1;Tie2-Cre embryos compared to controls, whereas the number of VEC(+) and dpERK co-stained cells is comparable. Compared to controls, Spry1;Tie2-Cre embryos also show a decrease in proliferation and an increase in apoptosis. Furthermore, loss of Spry1 results in an increase of CD41(+) and CD71(+) cells at E9.5 compared with controls.These data indicate that primitive hematopoietic cells derive from Tie2-expressing hemangioblasts and that Spry1 over expression inhibits primitive hematopoietic progenitor and erythroblastic cell development and expansion while having no obvious effect on endothelial cell development
Microwave processing of cement and concrete materials - towards an industrial reality?
Each year a substantial body of literature is published on the use of microwaves to process cement and concrete materials. Yet to date, very few if any have lead the realisation of a commercial scale industrial system and is the context under which this review has been undertaken. The state-of the–art is evaluated for opportunities, and the key barriers to the development of new microwave-based processing techniques to enhance production, processing and recycling of cement and concrete materials. Applications reviewed include pyro-processing of cement clinker; accelerated curing, non-destructive testing and evaluation (NDT&E), and end-of-life processing including radionuclide decontamination
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