A theoretical model of inflammation- and mechanotransduction- driven asthmatic airway remodelling

Inflammation, airway hyper-responsiveness and airway remodelling are well-established hallmarks of asthma, but their inter-relationships remain elusive. In order to obtain a better understanding of their inter-dependence, we develop a mechanochemical morphoelastic model of the airway wall accounting for local volume changes in airway smooth muscle (ASM) and extracellular matrix in response to transient inflammatory or contractile agonist challenges. We use constrained mixture theory, together with a multiplicative decomposition of growth from the elastic deformation, to model the airway wall as a nonlinear fibre-reinforced elastic cylinder. Local contractile agonist drives ASM cell contraction, generating mechanical stresses in the tissue that drive further release of mitogenic mediators and contractile agonists via underlying mechanotransductive signalling pathways. Our model predictions are consistent with previously described inflammation-induced remodelling within an axisymmetric airway geometry. Additionally, our simulations reveal novel mechanotransductive feedback by which hyper-responsive airways exhibit increased remodelling, for example, via stress-induced release of pro-mitogenic and procontractile cytokines. Simulation results also reveal emergence of a persistent contractile tone observed in asthmatics, via either a pathological mechanotransductive feedback loop, a failure to clear agonists from the tissue, or a combination of both. Furthermore, we identify various parameter combinations that may contribute to the existence of different asthma phenotypes, and we illustrate a combination of factors which may predispose severe asthmatics to fatal bronchospasms

P3HT-Based Solar Cells: Structural Properties and Photovoltaic Performance

Each year we are bombarded with B.Sc. and Ph.D. applications from students that want to improve the world. They have learned that their future depends on changing the type of fuel we use and that solar energy is our future. The hope and energy of these young people will transform future energy technologies, but it will not happen quickly. Organic photovoltaic devices are easy to sketch, but the materials, processing steps, and ways of measuring the properties of the materials are very complicated. It is not trivial to make a systematic measurement that will change the way other research groups think or practice. In approaching this chapter, we thought about what a new researcher would need to know about organic photovoltaic devices and materials in order to have a good start in the subject. Then, we simplified that to focus on what a new researcher would need to know about poly-3-hexylthiophene:phenyl-C61-butyric acid methyl ester blends (P3HT: PCBM) to make research progress with these materials. This chapter is by no means authoritative or a compendium of all things on P3HT:PCBM. We have selected to explain how the sample fabrication techniques lead to control of morphology and structural features and how these morphological features have specific optical and electronic consequences for organic photovoltaic device applications

The Synthesis, Self-Assembly and Self-Organisation of Polysilane Block Copolymers

Block copolymers containing polysilane blocks are unique in that the polysilane components possess electro-active properties and are readily photodegradable. This review will discuss and assess the two major approaches to the synthesis of polysilane block copolymers via pre-formed polymer chain coupling and living polymerisation techniques. The self-organisation of polysilane block copolymers and the morphologies adopted in thin films are reviewed. Amphiphilic polysilane-containing block copolymers self-assemble in solvents selective for one block and a number of examples are highlighted. The versatility of these materials is highlighted by recent significant applications including the preparation of hollow crosslinked micellar aggregates in aqueous solutions and in patterned thin film generation subsequently employed as templates for the growth of cell cultures and CaCO (3.

Mouse Lung Tissue Slice Culture

Precision-cut lung slices (PCLS) represent an ex vivo model widely used in visualizing interactions between lung structure and function. The major advantage of this technique is that the presence, differentiation state, and localization of the more than 40 cell types that make up the lung are in accordance with the physiological situation found in lung tissue, including the right localization and patterning of extracellular matrix elements. Here we describe the methodology involved in preparing and culturing PCLS followed by detailed practical information about their possible applications.</p

Nuclear medicine procedures in neuroblastoma

In NB diagnostic setting, nuclear medicine procedures have demonstrated major accuracy for both staging and treatment response assessments, including the evaluation of bone and bone marrow involvement. 123I-MIBG scintigraphy has been extensively used in research and clinical practice for over 35 years, representing the most important functional imaging modality in NB assessment. Furthermore, therapy with 131I-MIBG has been extensively employed in neuroblastoma since the late 1980s, with a systematic review analyzing 1121 patients treated with 131I-MIBG. 131I-MIBG was used as single agent (monotherapy) in patients with a poor prognosis, in particular those with recurrent/refractory disease, as a palliative treatment. So far, 131I-MIBG therapy is included in multicentric trials on high-risk neuroblastoma patients. However, in recent years, different types of “new” PET tracers have been introduced in the diagnostic workup of NB showing very promising results [21, 22]. In this new diagnostic scenario, it seems important to identify strengths and limitation of each different functional diagnostic modality. The aim of this chapter is to analyze, in terms of availability and accuracy, the principal nuclear medicine procedures used in NB. In addition, the prevalent or complementary role of each functional imaging method is highlighted

Origin, causes and effects of increased nitrite concentrations in aquatic environments

Literature frequently mentions increased nitrite concentrations along with its inhibitory effect towards bacteria and aquatic life. Nitrite accumulation has been studied for decades, and although numerous causal factors have already been commented on in literature, the mechanism of nitrite accumulation is not always clear. From the broad range of parameters and environmental factors reviewed in this paper, it is obvious that the causes and consequences of nitrite accumulation are not yet completely understood. Among others, pH, dissolved oxygen, volatile fatty acids, phosphate and reactor operation have been found to play a role in nitrite accumulation, which results from differential inhibition or disruption of the linkage of the different steps in both nitrification and denitrification. In the case of nitrification, this differential inhibition could lead to the displacement or unlinking of the ammonia oxidisers and nitrite oxidisers. In this paper, the idea is formulated that the nitrifier population forms a role model for the total microbial community. Increased nitrite concentrations would in this aspect not only signal a disruption of nitrifiers, but possibly also of the total configuration of the microbial community. [KEYWORDS: denitrification, nitrification, nitrite accumulation, nitrite toxicity]