Entamoeba histolytica: Lipid rafts are involved in adhesion of trophozoites to host extracellular matrix components

Adhesion is an important virulence function for Entamoeba histolytica, the causative agent of amoebic dysentery. Lipid rafts, cholesterol-rich domains, function in compartmentalization of cellular processes. In E. histolytica, rafts participate in parasite–host cell interactions; however, their role in parasite–host extracellular matrix (ECM) interactions has not been explored. Disruption of rafts with a cholesterol extracting agent, methyl-β-cyclodextrin (MβCD), resulted in inhibition of adhesion to collagen, and to a lesser extent, to fibronectin. Replenishment of cholesterol in MβCD-treated cells, using a lipoprotein–cholesterol concentrate, restored adhesion to collagen. Confocal microscopy revealed enrichment of rafts at parasite–ECM interfaces. A raft-resident adhesin, the galactose/N-acetylgalactosamine-inhibitable lectin, mediates interaction to host cells by binding to galactose or N-acetylgalactosamine moieties on host glycoproteins. In this study, galactose inhibited adhesion to collagen, but not to fibronectin. Together these data suggest that rafts participate in E. histolytica–ECM interactions and that raft-associated Gal/GalNAc lectin may serve as a collagen receptor

Isolation of nine microsatellite loci in Dolichogenidea homoeosomae (Hymenoptera) a parasitoid of the sunflower moth Homoeosoma electellum (Lepidoptera)

Nine microsatellite loci were isolated from the insect Dolichogenidea homoeosomae (Hymenoptera: Braconidae), an important parasitoid of the sunflower moth Homosoeosoma electellum (Lepidoptera: Pyralidae), and assayed for polymorphism. All nine loci were polymorphic within the five populations tested, with two to 14 alleles per locus. Expected and observed heterozygosities ranged from 0.39 to 0.90 and 0.25 to 0.72 respectively. These are the first microsatellite primers developed for D. homeosomae and will be useful for studies of population dynamics and connectivity. © 2006 Blackwell Publishing Ltd

Analysis of the OSU-MASLWR 001 and 002 tests by using the TRACE code

The Oregon State University (OSU) has constructed, under a U.S. Department of Energy grant, a scaled integral test facility to examine natural circulation phenomena characterizing the Multi-Application Small Light Water Reactor (MASLWR) design. The MASLWR is a small modular PWR relying on natural circulation during both steady-state and transient operation, which includes an integrated helical coil steam generator within the reactor pressure vessel. Testing has been conducted in order to assess the operation of the prototypical MASLWR under normal full pressure and full temperature conditions and to assess the passive safety systems performance. The experimental data produced are useful also for the assessment of the computational tools necessary for the operation, design and safety analysis of nuclear reactors. This report describes the assessment of TRACE code predictions, conducted under the NRC CAMP program, against the MASLWR tests OSU-MASLWR-001 and the OSU-MASLWR-002, respectively. This activity has been conducted in collaboration with the Italian National Agency for the New Technologies, Energy and Sustainable Economic Development (ENEA), the Department of Energy of the University of Palermo, the Gruppo di Ricerca Nucleare San Piero a Grado (GRNSPG) of University of Pisa, the Department of Nuclear Engineering and Radiation Health Physics at OSU and NuScale Power Inc. In particular the OSU-MASLWR-001 test, an inadvertent actuation of one submerged ADS valve, investigates the primary system to containment coupling under design basis accident conditions; the OSU-MASLWR-002 test, a natural circulation test, investigates the primary system flow rates and secondary side steam superheat for a variety of core power levels and feed water flow rates. The assessment against experimental data shows that the TRACE code predicts the main phenomena of interest of the selected tests reasonably well for most condition

(3-Anilino-1-phenyl­imino­thio­ureato)chloridodimethyl­tin(IV)

In the title compound, [Sn(CH3)2(C13H11N4S)Cl], the Sn atom is five-coordinated in a distorted trigonal-bipyramidal geometry, with two methyl groups and one S atom in the equatorial plane, and one N atom and the Cl atom occupying the apical positions

Spin-state driven ferromagnetic and spin glass states in layered LaSrCoO4_4

Famous for its spin-state puzzle, LaSrCoO$_4$ (Co$^{3+}$) is an intermediate between antiferromagnetic (AFM) La$_2$CoO$_4$ (Co$^{2+}$) and ferromagnetic (FM) Sr$_2$CoO$_4$ (Co$^{4+}$). The appearance of the Co$^{3+}$ valence state (not present in the end compounds) is intriguing because of the spin-state transitions associated with it. In this work, we report two magnetic transitions in LaSrCoO$_4$: (i) a transition at T $=$ T$_c$ $\simeq$ 225 K, from the paramagnetic state to a state with an inhomogeneous long-range ferromagnetic (FM) order wherein finite FM clusters coexist with infinite FM matrix in the percolation sense, and (ii) the transition to the cluster spin glass (CSG) state at T $=$ T$_g$ $\simeq$ 8 K. Finite FM clusters (which at low temperatures give rise to the cluster spin glass state) and infinite FM matrix are formed due to the spin-spin interactions brought about by the inhomogeneously distributed Co$^{3+}$ high spin (HS) and Co$^{3+}$ low spin (LS) ions. A firm support to the presence of an unconventional (inhomogeneous) ferromagnetic order comes from the anomalous values of the critical exponents $\beta$, $\gamma$ and $\delta$ for the spontaneous magnetization, `zero-field' magnetic susceptibility and the critical M - H isotherm, while the coexistence of HS Co$^{3+}$ and LS Co$^{3+}$ ions is confirmed by the results of the extended X-ray absorption fine structure spectroscopy.Comment: 18 pages, 6 figure