Neurotensin is an antagonist of the human neurotensin NT2 receptor expressed in Chinese hamster ovary cells

The human levocabastine-sensitive neurotensin NT2 receptor was cloned from a cortex cDNA library and stably expressed in Chinese hamster ovary (CHO) cells in order to study its binding and signalling characteristics. The receptor binds neurotensin as well as several other ligands already described for neurotensin NT1 receptor. It also binds levocabastine, a histamine H1 receptor antagonist that is not recognised by neurotensin NT1 receptor. Neurotensin binding to recombinant neurotensin NT2 receptor expressed in CHO cells does not elicit a biological response as determined by second messenger measurements. Levocabastine, and the peptides neuromedin N and xenin were also ineffective on neurotensin NT2 receptor activation. Experiments with the neurotensin NT1 receptor antagonists SR48692 and SR142948A, resulted in the unanticipated discovery that both molecules are potent agonists on neurotensin NT2 receptor. Both compounds, following binding to neurotensin NT2 receptor, enhance inositol phosphates (IP) formation with a subsequent [Ca2+]i mobilisation; induce arachidonic acid release; and stimulate mitogen-activated protein kinase (MAPK) activity. Interestingly, these activities are antagonised by neurotensin and levocabastine in a concentration-dependent manner. These activities suggest that the human neurotensin NT2 receptor may be of physiological importance and that a natural agonist for the receptor may exist.     

Biodegradable hollow fibres containing drug‐loaded nanoparticles as controlled release systems

A ‘multiple’ delivery system was studied, consisting of hollow microfibres containing drug‐loaded nanoparticles. Both fibres and nanoparticles are made of biodegradable polymers, so that the system does not need any surgical operation to be removed. The main advantage of the system is that it allows the contemporaneous release of different kinds of drugs. Copolymers of poly(lactic acid) and ?‐caprolactone were used for the preparation of the fibres through both wet and dry–wet spinning procedures. Two types of nanoparticles, gelatin and poly(DL ‐lactide‐co‐glycolide) nanoparticles, were prepared by simple water‐in‐oil and oil‐in‐water emulsions, respectively. Drugs such as dexamethasone and methotrexate were used to load the particles. The technique employed for the preparation of the nanoparticles filled fibres was described and the drug release characteristics of this system were investigated and compared with those of the free nanoparticles. © 2002 Society of Chemical Industry     

A simple polarimetric field characterisation in reverberating chambers

A reverberating chamber (RC) is an electrically large cavity in which the electromagnetic field is properly randomised. The randomisation process generates a non-planar field. Here, the recent polarimetric characterisation of non-planar fields is first introduced to describe the field in an RC. The approach is simple and effective and is used on measured data acquired at the mode-stirred RC available at the Universita degli Studi di Napoli Parthenope, formerly Istituto Universitario Navale (IUN). The approach provides a quantitative evaluation of the RC field randomisation process.     

Condom use in clients of prostitutes in Spain

Live eosinophils when mixed with Acridine Orange solution and viewed microscopically using u.v. light show very intense colours of their granules (yellow, orange and red) and green nuclear staining. Their active movement, translocation of granules and degranulation can be observed in vitro. Using this method, live eosinophils can be easily differentiated and enumerated.     

The contributions of “minimum primary emissions” and “new particle formation enhancements” to the particle number concentration in urban air

In an urban site affected by fresh vehicle exhaust emissions, the ambient air number concentrations of particles coarser than 3 nm (N) was split into two components, N=N1+N2. This was done using a method based on the high correlation between black-carbon (BC) and number (N) concentrations which is typically observed in ambient air and is the result of vehicle exhaust emissions. The component N1 accounts for “those aerosol components directly emitted in the particle phase” and “those components nucleating immediately after emission”. The component N2 accounts for the new particle formation enhancements during the “dilution and cooling of the vehicle exhaust” and is also influenced by “in situ new particle formation in ambient air”. The contribution of N1 to N exhibits a maximum of 55% during the morning rush hours (07:00–08:00). The contribution of N2 to N exhibits a daily evolution with a broad maximum during daylight (as solar radiation intensity), while for about 7 h (11:00–17:00) the N2 contribution to N is about 70%. During some “afternoon N2 events”, N2 contributions exceeded 90%. Enhancements in the new particle formation processes may increase the N/BC concentrations ratio in one order of magnitude, from 4.82×10⁶ particles/ng BC to 47×10⁶ particles/ng BC and during some events up to 97×10⁶ particles/ng BC. The results show evidence of the high potential of the vehicle exhausts and of the urban atmosphere to trigger new particle formation if the ambient air conditions are favourable. The method used in this study is useful in assessing future changes in the number to BC relationship due to forthcoming regulations in the vehicle exhaust emissions.     

Mixing local and global information for community detection in large networks

Clustering networks play a key role in many scientific fields, from Biology to Sociology and Computer Science. Some clustering approaches are called global because they exploit knowledge about the whole network topology. Vice versa, so-called local methods require only a partial knowledge of the network topology. Global approaches yield accurate results but do not scale well on large networks; local approaches, vice versa, are less accurate but computationally fast. We propose CONCLUDE (COmplex Network CLUster DEtection), a new clustering method that couples the accuracy of global approaches with the scalability of local methods. CONCLUDE generates random, non-backtracking walks of finite length to compute the importance of each edge in keeping the network connected, i.e., its edge centrality. Edge centralities allow for mapping vertices onto points of a Euclidean space and compute all-pairs distances between vertices; those distances are then used to partition the network into clusters.     

Stress Measurement Technique to Monitor Porous Silicon Processing

Macroscopic stress measurements are used to monitor Porous Silicon processing. Silicon wafer of 1 cm resistivity, n-type and 1 0 0 orientation were used as starting material. Porous Silicon layers with a porosity of 57% and a thickness of 85 m, fabricated by electrochemical anodisation, were differently dried, then the evolution of the wafer deflection has been followed with storage time in air. Thermal treatments both in inert and oxidant atmosphere have been performed up to 1000°C. The stress behaviour vs. temperature allows to estimate the hydrogen desorption activation energy.     

Multi-Input Second-Order Sliding-Mode Hybrid Control of Constrained Manipulators

This paper deals withthe hybrid position/force control of constrainedmanipulators subjected to uncertainties. A solution is proposedthat is based on sliding-mode control theory, which proved tobe highly effective in counteracting uncertainties for some classesof nonlinear systems. Specific problems involved in this techniqueare chattering elimination and the algebraic coupling betweenconstraint forces and possibly discontinuous control signals.Both the problems are addressed in this paper by exploiting therobustness properties of a second-order sliding-mode controlalgorithm. This algorithm, recently proposed by the authors forsolving the single-input hybrid control problem, is generalizedin this paper to deal with the class of multi-input differentialalgebraic systems describing the behaviour of constrained mechanicalsystems.     

Comments on "Fusion of body surface potential and body surface Laplacian signals for electrocardiographic imaging"

D.B. Geselowitz and J. Ferrara comment on a paper by R.D. Throne and L.G. Olson which was published in ibid., vol.47, p. 452-62 (2000). Throne and Olson reply to these comments. The discussion concerns the use of a spherical model and a body surface Laplacian in the solution of the electrocardiographic inverse problem and the influence of noise     

Selective hydrogenation of sunflower oil over Ni catalysts

This work focuses on the influence of the support and the preparation method on the activity and selectivity of nickel catalysts in the hydrogenation of sunflower oil. Catalysts were prepared over silica and alumina supports following the incipient wetness impregnation and deposition-precipitation techniques. The activation process was followed by temperature-programmed reduction (TPR). Precipitation-deposition method allowed a stronger metal-support interaction than incipient wetness impregnation. A precipitation-deposition time of 14 h (which allowed a Ni loading of about 20wt%) was deemed as the most adequate from the standpoint of high specific surface area and strong Ni-support interaction. The selectivity to oleic acid was not affected by the preparation method, but it was significantly influenced by the type of support. In this regard, the catalysts prepared on silica are more active and produce less saturated fatty acids.