Overexpression of the MYB29 transcription factor affects aliphatic glucosinolate synthesis in Brassica oleracea

Plant Molecular Biology - Overexpression of BoMYB29 gene up-regulates the aliphatic glucosinolate pathway in Brassica oleracea plants increasing the production of the anti-cancer metabolite...     

Role of Langerhans cells in the immunity of leishmaniasis

Immune response induced against Leishmania parasites is influenced by several factors, one of the most important being the type of Antigen Presenting Cell (APC). Langerhans cells, a subpopulation of APC, are sentinel cells for detecting invader microorganisms; they reside in skin tissues at levels where the phlebotomine fly vector inoculates Leishmania parasites. Presence of microorganisms can induce activation of Langerhans cells, leading to their maturation and migration towards lymph nodes. There, Langerhans cells present antigens to T cells for their subsequent activation and specific differentiation into effector cells. Early after a Leishmania infection, few T cells have been observed at sites of infection, suggesting that infected macrophages have little opportunity to locate T cells specific for elimination of Leishmania parasites. However, Langerhans cells may be the cells available to provide signals for the stimulation of parasite-specific T-cell responses in the lymph node and for inducing T-cell migration to the infected skin. Herein, the main characteristics of Langerhans cells are reviewed, with special emphasis on their participation in cutaneous inflammatory response. The role of these cells in infections caused by protozoan parasites of the Leishmania genus is discussed.     

Minor- and trace-element intra-shell variations in Santonian inoceramids (Basque-Cantabrian Basin,northern Spain): diagenetic and primary causes

Santonian deep- and platform-marine facies inoceramids from the Basque-Cantabrian Basin show clear saw-toothed intra-shell variations with respect to Mg/Ca, Sr/Ca, Na/Ca, Ba/Ca, Fe/Ca and Mn/Ca ratios. Under cathodoluminescence, the most luminescent zones in all the inoceramids present lower Mg/Ca and Sr/Ca (up to 48% and 35% lower values, respectively) and higher Fe/Ca and Mn/Ca ratios (up to 362% and 819% higher values, respectively), which is indicative of diagenetic modification. In contrast, the least luminescent zones show higher Mg/Ca and Sr/Ca ratios and lower Fe/Ca and Mn/Ca. These findings, along with the presence of frequent, well-correlated Mg/Ca, Sr/Ca and Na/Ca ratios, inversely related to Fe/Ca and Mn/Ca, in the weakest luminescent zones suggest major retention of the primary intra-shell variations in these zones. Moreover, Ba/Ca profiles, not connected with the general cathodoluminescence behaviour of the shells, also point towards partial retention of the primary patterns. The saw-toothed intra-shell variations are thought to be caused by the distinct geochemical signals acquired originally by the inoceramid alternating clear and dark growth lines. The deposition of the growth lines and thus the saw-toothed intra-shell variations may be mainly related to periodically changing palaeoenvironmental conditions, such as seawater temperature variations and phytodetritus rainfall. This interpretation is supported by the appearance of highly similar chemical saw-toothed variations in the extant shallow-marine Atrina rigida shell.     

Optimization of culture conditions to obtain maximal growth of penicillin-resistant <Emphasis Type="Italic">Streptococcus pneumoniae</Emphasis>

Background  

Streptococcus pneumoniae, particularly penicillin-resistant strains (PRSP), constitute one of the most important causes of serious infections worldwide. It is a fastidious microorganism with exquisite nutritional and environmental requirements to grow, a characteristic that prevents the development of useful animal models to study the biology of the microorganism. This study was designed to determine optimal conditions for culture and growth of PRSP.     

Survival Tests for r Groups

In this paper we give the generalization of the score tests covering the case of ties and we give examples where the expressions in matrix form are completely specified for the weighted tests and the score tests for the case of r groups. It is worth mentioning that although the score tests are not generally included in the commercial software, these tests should be used if it can be assumed that the censoring mechanism is equal in the r groups or if there is no censoring (Lawless , 1982). We establish the equivalence between “numerators” of these families of tests. As result of this equivalence we define four new tests that complete the classification of score and weighted tests. The Kruskal‐Wallis test (1952) appears as a particular case of the score tests for the case of non‐censoring. A simulation study has been done in order to compare the performance of the tests described in this paper. An example is included to make the understanding of the paper easier.