The Role of the Spleen in Lymphocyte Migration

In all species studied so far it was found that more lymphocytes migrate to the spleen than to all the lymph nodes together. Specific molecules on lymphocytes and endothelial cells regulate their entry into lymph nodes, but none of the known molecules play a role in homing to the spleen. The splenic compartments, comprising the red pulp, marginal zone, periarterial lymphatic sheath (PALS) and follicles, all show different kinetics for migrating lymphocytes. By combining 51Cr lymphocyte labeling with morphometry and two color immunohistochemistry, the migratory route of lymphocyte subsets can be followed through the spleen and absolute numbers of lymphocytes calculated in each compartment. T lymphocytes home preferentially to the PALS and B lymphocytes home not only to follicles but also in large numbers to the marginal zone and red pulp. CD4+ and CD8+ lymphocytes migrate similarly at early time points, but at 24 hours CD4+ lymphocytes are preferentially found in the PALS with CD8+ lymphocytes in the red pulp and marginal zone. The functional significance of the different routes of lymphocytes through the spleen has yet to be defined in relationship to specific immune functions and regulatory factors on splenic lymphocyte homing

What is the clinical relevance of different lung compartments?

The lung consists of at least seven compartments with relevance to immune reactions. Compartment 1 - the bronchoalveolar lavage (BAL), which represents the cells of the bronchoalveolar space: From a diagnostic point of view the bronchoalveolar space is the most important because it is easily accessible in laboratory animals, as well as in patients, using BAL. Although this technique has been used for several decades it is still unclear to what extent the BAL represents changes in other lung compartments. Compartment 2 - bronchus-associated lymphoid tissue (BALT): In the healthy, BALT can be found only in childhood. The role of BALT in the development of the mucosal immunity of the pulmonary surfaces has not yet been resolved. However, it might be an important tool for inhalative vaccination strategies. Compartment 3 - conducting airway mucosa: A third compartment is the bronchial epithelium and the submucosa, which both contain a distinct pool of leukocytes (e.g. intraepithelial lymphocytes, IEL). This again is also accessible via bronchoscopy. Compartment 4 - draining lymph nodes/Compartment 5 - lung parenchyma: Transbronchial biopsies are more difficult to perform but provide access to two additional compartments - lymph nodes with the draining lymphatics and lung parenchyma, which roughly means "interstitial" lung tissue. Compartment 6 - the intravascular leukocyte pool: The intravascular compartment lies between the systemic circulation and inflamed lung compartments. Compartment 7 - periarterial space: Finally, there is a unique, lung-specific space around the pulmonary arteries which contains blood and lymph capillaries. There are indications that this "periarterial space" may be involved in the pulmonary host defense

Carbon radio recombination lines from gigahertz to megahertz frequencies towards Orion A

Context. The combined use of carbon radio recombination lines (CRRLs) and the 158 $\mu$m-[CII] line is a powerful tool for the study of the energetics and physical conditions (e.g., temperature and density) of photodissociation regions (PDRs). However, there are few observational studies that exploit this synergy. Aims. Here we explore the relation between CRRLs and the 158 $\mu$m-[CII] line in light of new observations and models. Methods. We present new and existing observations of CRRLs in the frequency range 0.15--230 GHz with ALMA, VLA, the GBT, Effelsberg 100m, and LOFAR towards Orion~A (M42). We complement these observations with SOFIA observations of the 158 $\mu$m-[CII] line. We studied two PDRs: the foreground atomic gas, known as the Veil, and the dense PDR between the HII region and the background molecular cloud. Results. In the Veil we are able to determine the gas temperature and electron density, which we use to measure the ionization parameter and the photoelectric heating efficiency. In the dense PDR, we are able to identify a layered PDR structure at the surface of the molecular cloud to the south of the Trapezium cluster. There we find that the radio lines trace the colder portion of the ionized carbon layer, the C$^{+}$/C/CO interface. By modeling the emission of the $158$~$\mu$m-[CII] line and CRRLs as arising from a PDR we derive a thermal pressure $>5\times10^{7}$ K cm$^{-3}$ and a radiation field $G_{0}\approx10^{5}$ close to the Trapezium. Conclusions. This work provides additional observational support for the use of CRRLs and the 158 $\mu$m-[CII] line as complementary tools to study dense and diffuse PDRs, and highlights the usefulness of CRRLs as probes of the C$^{+}$/C/CO interface.Comment: 18 pages, 16 figures, accepted for publication in A&

Probing of local ferroelectricity in BiFeO3 thin films and (BiFeO3)m(SrTiO3)m superlattices

Ferroelectric BiFeO3 thin films and artificial superlattices of (BiFeO3)m(SrTiO3)m (m~ 1 to 10 unit cells) were fabricated on (001)-oriented SrTiO3 substrates by pulsed laser ablation. The variation of leakage current and macroscopic polarization with periodicity was studied. Piezo force microscopy studies revealed the presence of large ferroelectric domains in the case of BiFeO3 thin films while a size reduction in ferroelectric domains was observed in the case of superlattice structures. The results show that the modification of ferroelectric domains through superlattice, could provide an additional control on engineering the domain wall mediated functional properties.Comment: 14 pages, To be published in J. Mag. Mag Mater. proceedings of EMRS 200

Consumers’ reactions to nutrition and ingredient labelling for wine – A cross-country discrete choice experiment

The purpose of this study is to examine consumers' reactions to the introduction of nutrition and ingredient labelling for wine, a product that is so far still exempt from mandatory nutrition and ingredient labelling. It also analyses the effect of positive and negative information about the use of ingredients in wine on consumers' choice. Representative samples for wine consumers from three distinctly different countries representing old and new wine markets (Australia, n = 745; Germany, n = 716; Italy, n = 715) completed a discrete choice experiment (DCE) with graphically simulated wine back labels. For each country, respondents were randomly allocated to a reference group and two different treatment conditions where they received newspaper-like information (positive, negative) before making choices. Results for the reference condition show that consumers across all three countries have a significant positive utility for detailed nutrition information. Instead, ingredient information only receives a positive utility in Italy, whereas German and Australian respondents do not receive utility from ingredient labelling. When consumers in the treatment group are confronted with negative media information the attribute importance of ingredients significantly increases across all three countries, clean labelled products without ingredients are preferred, and a significantly higher share of consumers in Germany and Italy prefer not to buy any wine. The treatment effect of positive media information on consumers’ wine choice is lower than that of negative information. The results of the study have implications for the pending new regulation of wine labelling and for communication strategies of the wine industry that should actively inform consumers about the necessity of ingredients in wine production