197 research outputs found
Salt-dependent regulation of a CNG channel subfamily in Arabidopsis
<p>Abstract</p> <p>Background</p> <p>In <it>Arabidopsis thaliana</it>, the family of cyclic nucleotide-gated channels (CNGCs) is composed of 20 members. Previous studies indicate that plant CNGCs are involved in the control of growth processes and responses to abiotic and biotic stresses. According to their proposed function as cation entry pathways these channels contribute to cellular cation homeostasis, including calcium and sodium, as well as to stress-related signal transduction. Here, we studied the expression patterns and regulation of <it>CNGC19 </it>and <it>CNGC20</it>, which constitute one of the five CNGC subfamilies.</p> <p>Results</p> <p>GUS, GFP and luciferase reporter assays were used to study the expression of <it>CNGC19 </it>and <it>CNGC20 </it>genes from <it>Arabidopsis thaliana </it>in response to developmental cues and salt stress. <it>CNGC19 </it>and <it>CNGC20 </it>were differentially expressed in roots and shoots. The <it>CNGC19 </it>gene was predominantly active in roots already at early growth stages. Major expression was observed in the phloem. <it>CNGC20 </it>showed highest promoter activity in mesophyll cells surrounding the veins. Its expression increased during development and was maximal in mature and senescent leaves. Both genes were upregulated in the shoot in response to elevated NaCl but not mannitol concentrations. While in the root, <it>CNGC19 </it>did not respond to changes in the salt concentration, in the shoot it was strongly upregulated in the observed time frame (6-72 hours). Salt-induction of <it>CNGC20 </it>was also observed in the shoot, starting already one hour after stress treatment. It occurred with similar kinetics, irrespective of whether NaCl was applied to roots of intact plants or to the petiole of detached leaves. No differences in K and Na contents of the shoots were measured in homozygous T-DNA insertion lines for <it>CNGC19 </it>and <it>CNGC20</it>, respectively, which developed a growth phenotype in the presence of up to 75 mM NaCl similar to that of the wild type.</p> <p>Conclusion</p> <p>Together, the results strongly suggest that both channels are involved in the salinity response of different cell types in the shoot. Upon salinity both genes are upregulated within hours. <it>CNGC19 </it>and <it>CNGC20 </it>could assist the plant to cope with toxic effects caused by salt stress, probably by contributing to a re-allocation of sodium within the plant.</p
Transition from van-der-Waals to H Bonds dominated Interaction in n-Propanol physisorbed on Graphite
Multilayer sorption isotherms of 1-propanol on graphite have been measured by
means of high-resolution ellipsometry within the liquid regime of the adsorbed
film for temperatures ranging from 180 to 260 K. In the first three monolayers
the molecules are oriented parallel to the substrate and the growth is roughly
consistent with the Frenkel-Halsey-Hill-model (FHH) that is obeyed in
van-der-Waals systems on strong substrates. The condensation of the fourth and
higher layers is delayed with respect to the FHH-model. The fourth layer is
actually a bilayer. Furthermore there is indication of a wetting transition.
The results are interpreted in terms of hydrogen-bridge bonding within and
between the layers.Comment: 4 pages, 3 figure
Impact of different antithrombotics on the microcirculation and viability of perforator-based ischaemic skin flaps in a small animal model
The effects of antithrombotic drugs on random and free flap survival have been investigated in the past, but the experimental and clinical results are not in agreement. A perforator-based critical ischaemia model was used to evaluate the effects of different perioperatively administered pharmaceutical agents on tissue ischaemia and to assess the potential additional haemorheological or vasodilative effects of antithrombotics on flap microcirculation. Combined laser Doppler flowmetry and remission spectroscopy revealed an increase in certain microcirculation parameters in most groups in comparison with saline controls, and these changes correlated with flap survival. Clopidogrel and hirudin significantly improved the amount of viable flap tissue in comparison with controls, while unfractioned heparin had a negative effect on flap survival. Low molecular weight heparin, aspirin, pentoxifylline, and hydroxyethyl starch had no impact on the amount of viable flap tissue. A higher complication rate was observed in all experimental groups, but only clopidogrel had a negative impact on the flap viability. Our results add to the body of evidence supporting the conclusion that perioperative antithrombotic treatment improves flap survival. Clopidogrel and hirudin are effective pharmacological agents that significantly increased the viability of perforator-based skin flaps in rats, but at a higher risk of postoperative bleeding
Impact of different antithrombotics on the microcirculation and viability of perforator-based ischaemic skin flaps in a small animal model
The effects of antithrombotic drugs on random and free flap survival have been investigated in the past, but the experimental and clinical results are not in agreement. A perforator-based critical ischaemia model was used to evaluate the effects of different perioperatively administered pharmaceutical agents on tissue ischaemia and to assess the potential additional haemorheological or vasodilative effects of antithrombotics on flap microcirculation. Combined laser Doppler flowmetry and remission spectroscopy revealed an increase in certain microcirculation parameters in most groups in comparison with saline controls, and these changes correlated with flap survival. Clopidogrel and hirudin significantly improved the amount of viable flap tissue in comparison with controls, while unfractioned heparin had a negative effect on flap survival. Low molecular weight heparin, aspirin, pentoxifylline, and hydroxyethyl starch had no impact on the amount of viable flap tissue. A higher complication rate was observed in all experimental groups, but only clopidogrel had a negative impact on the flap viability. Our results add to the body of evidence supporting the conclusion that perioperative antithrombotic treatment improves flap survival. Clopidogrel and hirudin are effective pharmacological agents that significantly increased the viability of perforator-based skin flaps in rats, but at a higher risk of postoperative bleeding
Comparison of three-dimensional imaging of the nose using three different 3D-photography systems: an observational study
New 3D technologies for superficial soft tissue changes, especially in plastic and reconstructive surgical procedures, can improve the planning and documentation of facial surgeries. The purpose of this study was to compare and determine the applicability and feasibility of three different 3D-photography systems in clinical practice imaging the nose
«Diseño para todos» en la investigación social sobre personas con discapacidad
[EN] Social studies on disability have increased in number and importance in
Spain and other countries over the last few years. Nevertheless, the
majority of the available sources and studies do not adequately
represent this heterogeneous group, which currently makes up about 9
per cent of the Spanish population. The implementation of social
measures requires representative sources and studies containing
relevant information. The aim of this paper is to identify the main
diffi culties involved in designing and developing social research
methods concerning persons with disabilities, and offer proposals and
recommendations in order to advance towards a more inclusive social
research using the concepts of accessibility and design for all.[ES] Los estudios sociales sobre la discapacidad han aumentado en número e
importancia en España y otros países durante los últimos años. Sin
embargo, la mayoría de fuentes de información y estudios disponibles no
recogen de manera adecuada la realidad de un colectivo muy heterogéneo,
que supone en la actualidad aproximadamente el 9 por ciento de la
población española. La implementación de medidas sociales requiere de
fuentes y estudios representativos que aporten información precisa
acerca de estas personas. El objetivo de esta nota es identifi car las
principales difi cultades que se plantean a la hora de diseñar y llevar
a la práctica metodologías de investigación social adecuadas hacia las
personas con discapacidad, así como ofrecer propuestas y recomendaciones
para avanzar hacia una investigación social más inclusiva,
mediante los conceptos de accesibilidad y diseño para todos.Work carried out as part of the framework of research projects: “Qualitative Tracking with Young Disabled in European States. Quali-TYDES” (European Science Foundation, 09-ECRP-032) and “Hidden Innovation: paradigm shift in innovation studies” (Spanish Ministry of Economy and Competitiveness, FFI2011-25475).Peer reviewe
Development of a template tool for facilitating fibula osteotomy in reconstruction of mandibular defects by digital analysis of the human mandible
Abstract
Objectives
Mandibular reconstruction after segmental mandibulectomy can be challenging without virtual surgical planning and osteotomy guides. The purpose of this study was to analyze anatomic parameters to facilitate the evaluation of ideal fibula wedge osteotomies to reconstruct the neomandibula in a simple and cost-effective manner without the need for preoperative virtual planning.
Materials and methods
Computed tomography scans were acquired from randomly selected patients, and all images were obtained from routine clinical diagnostics, e.g., tumor staging, or preoperatively before reconstruction. Data was used to calculate stereolithographic models of the mandible for length and angle measurements. Statistical analysis was performed (p < 0.05).
Results
CT scans of 100 patients were analyzed: 39 were female and 61 were male patients, mean age was 59.08a. The mandibular arch angle proved to be constant with 241.07 ± 2.39°. The outside B-segment length was 80.05 ± 5.16 mm; the anterior S-segment length was 27.69 ± 3.16 mm. The angle of the mandibular arch showed differences in means (p = 0.004) between age groups, but effect was proved low. No relevant statistical significances were detected.
Conclusions
The development of a mandible reconstruction template tool would benefit the majority of head and neck patients, which is due to a constant mandibular arch angle and symphysis segment length throughout the general patient population, allowing the mimicking of a harmonic mandibular arch with up to three fibula segments.
Clinical relevance
The developed mandible reconstruction template tool can facilitate the fibula wedge osteotomies necessary for reconstruction of an ideal neomandibula providing a novel approach which is simple and cost-effective
Measurement of electron beam transverse flux density distribution
The work presents experimental measurements of electron beam transverse flux density distribution. Experimental data is recorded during the multiple beam scanning in different directions with the particular angle step by the thin scintillation strip. The intensity of the light generated in the scintillator is proportional to the intensity of the radiation going through the strip. Generated photons is guided by the optical fiber to the photomultiplier and registered by the analyzer. The result of the work is the experimental data demonstrated dependence of the radiation intensity on detecting strip position and angle orientation. This dependence is transformed to the radiation intensity dependence on the coordinates in the beam transverse plane using special mathematical processing
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