Impact of mobile clinical analyzers on disaster medicine: a lesson from crush syndrome in the 1995 Hanshin-Awaji earthquake

The Great Hanshin-Awaji earthquake caused many people to develop crush syndrome. Analysis of these patients revealed that the severity is not related to their hemodynamics but to hematocrit, base deficits, and potassium concentrations soon after their extrications. In the disaster site, these parameters can only be measured using whole-blood samples by mobile instruments. The present study was made to evaluate the possibility of uses of a mobile measuring device, ABL77, for the triage of crush syndrome patients in disaster sites. Heparin-added blood samples and serum samples were collected from patients admitted to Senshu Critical Care Medical Center. Blood gases, electrolytes, and hematocrit of the heparin-added blood samples were measured using ABL77 and compared with those measured using the stationary device ABL725. Potassium concentrations of the heparin-added blood samples measured by the ABL77 were compared with those of the serum samples measured by the stationary EA06T. Significant correlations were observed between the measurements. We conclude that the ABL77 was satisfactorily compatible with stationary devices in the hospital. Medical institutions should have simplified, mobile measuring devices as a precaution against disasters, so that they can get ready to take appropriate action promptly.     

Ring nitrogen-substituted non-steroidal estrogens: pyridine and pyrimidine analogs of the phenol in deoxyhexestrol experience resonance constraints on preferred ligand conformation

To develop compounds selective for estrogen receptor beta (ERbeta), we substituted hydroxypyridine and pyrimidine heteroaryl groups for the characteristic phenol ring of non-steroidal estrogens. The unexpectedly low affinity showed by some of these compounds is ascribed, in part, to a resonance-enforced conformational constraint that prevents their optimal accommodation in the ER ligand binding pocket.     

The Chapman-Enskog procedure for an age-structured population model: initial, boundary and corner layer corrections

We consider a mathematical model of an age-structured population of some fisheries (for example, anchovies, sardines or soles). Two time scales are involved in the problem: the fast time scale for the migration dynamics and the slow time scale for the demographic process. At a first step, we study the so called 'aggregated' system by means of the semigroups theory. Then, we study the asymptotic behaviour of the model by using the Chapman-Enskog procedure. In particular, we study initial, boundary and corner layer effects in order to obtain the exact initial and boundary conditions the approximated solution has to satisfy.     

The group B streptococcal beta and pneumococcal Hic proteins are structurally related immune evasion molecules that bind the complement inhibitor factor H in an analogous fashion

Complement evasion by different mechanisms is important for microbial virulence and survival in the host. One strategy used by pathogenic bacteria is to bind the soluble complement inhibitor factor H (fH) to their surfaces. In group B streptococci and pneumococci, fH binding has been shown to be mediated by the surface proteins beta and Hic, respectively. We showed previously that Hic binds to the middle region of fH and protects the pneumococcus from opsonophagocytosis. As the beta protein and Hic are structurally closely related, we wanted to compare the fH binding characteristics of these two proteins. By using direct binding assays with radiolabeled proteins and surface plasmon resonance analysis we show that both beta and Hic bind to the short consensus repeats 8-11 and 12-14 in the middle region of fH. Peptide mapping analysis suggested that the fH-binding sites on beta and Hic were composed of discontinuous and partially homologous sequences. Thus, the bacterial virulence proteins use multiple binding sites on fH to secure high avidity. Also, the functionally active sites on fH are thereby left free to inhibit C3b deposition and opsonophagocytosis. These results reveal the evolutionary conservation of an analogous immune evasion strategy in different types of pathogenic streptococci. Importantly, the respective virulence factors could be exploited in the development of protein-based vaccines against these pathogens.     

Interdomain contact regions and angles between adjacent short consensus repeat domains

The short consensus repeat domain (SCR, complement control protein module, sushi-domain) is a structural unit found in multiple adjacent copies in more than 40 human proteins. Each bead-like domain is composed of approximately 60 residues and the adjacent domains are connected in a head-to-tail fashion with linkers that consist of two to 12 amino acid residues. Based on experimentally determined structures the neighbouring SCR domains interact with each other at the so-called hinge or interdomain contact region. The functions mediated by the SCR domains have been studied using mutagenesis but the possible effects of the mutations on the hinge regions and interdomain angles have not been analysed. In this study, the linker and three loops in conserved locations were found to be responsible for the interdomain contact regions of all the solved experimental structures. The interdomain contact regions were identified in sequences of 140 human SCR domain pairs, and distinct hydrophobic and charge features were found in different subsets of SCR proteins and functional domains. To compare the possible associations of the interdomain contact region characteristics to the interdomain orientations all the experimentally solved SCR structures were subjected to a uniform calculation of tilt, twist, and skew angles that define the interdomain orientation. The twist and skew angles were found to have a linear correlation and the spatial location of one loop of the N-terminal domain (N#1) was found to have an effect on the skew angle. Thus, we describe location of the interdomain contact regions in primary structures of SCR domains and report that the orientation of adjacent SCR domains is not random and depends partially on the interdomain contact regions. On the basis of these results, mutations within the interdomain contact regions and subsequent loss-of-function effects caused by changes in the interdomain orientation can be avoided in mutagenesis studies.     

Exceptional resistance of human H2 glioblastoma cells to complement-mediated killing by expression and utilization of factor H and factor H-like protein 1

Of over 20 nucleated cell lines we have examined to date, human H2 glioblastoma cells have turned out to be the most resistant to complement-mediated cytolysis in vitro. H2 cells expressed strongly the membrane attack complex inhibitor protectin (CD59), moderately CD46 (membrane cofactor protein) and CD55 (decay-accelerating factor), but no CD35 (complement receptor 1). When treated with a polyclonal anti-H2 Ab, anti-CD59 mAb, and normal human serum, only 5% of H2 cells became killed. Under the same conditions, 70% of endothelial-like EA.hy 926 cells and 40% of U251 control glioma cells were killed. A combined neutralization of CD46, CD55, and CD59 increased H2 lysis only minimally, demonstrating that these complement regulators are not enough to account for the resistance of H2 cells. After treatment with Abs and serum, less C5b-9 was deposited on H2 than on U251 and EA.hy 926 cell lines. A reason for the exceptional resistance of H2 cells was revealed when RT-PCR and protein biochemical methods showed that the H2 cells, unlike the other cell lines tested, actively produced the soluble complement inhibitors factor H and factor H-like protein 1. H2 cells were also capable of binding human factor H from the fluid phase to their cell surface and promoted the cleavage of C3b to its inactive form iC3b more efficiently than U251 and EA.hy 926 cells. In accordance, anti-factor H mAbs enhanced killing of H2 glioblastoma cells. Taken together, our results show that production and binding of factor H and factor H-like protein 1 is a novel mechanism that these malignant cells utilize to escape complement-mediated killing.     

The surface protease PgtE of Salmonella enterica affects complement activity by proteolytically cleaving C3b, C4b and C5

Complement activity in mammalian serum is fundamentally based on three homologous components C3b, C4b and C5. During systemic infection, the gastrointestinal pathogen Salmonella enterica disseminates within host phagocytic cells but also extracellularly. Consequently, systemic Salmonella transiently confronts the complement system. We show here that the surface protease PgtE of S. enterica proteolytically cleaves C3b, C4b and C5 and that the expression of PgtE enhances bacterial resistance to human serum. Degradation of C3b was further enhanced by PgtE-mediated plasminogen activation.     

The complement regulator factor H binds to the surface protein OspE of Borrelia burgdorferi

Spirochete bacteria of the Borrelia burgdorferi sensu lato complex cause Lyme borreliosis. The three pathogenic subspecies Borrelia garinii, Borrelia afzelii, and Borrelia burgdorferi sensu stricto differ in their disease profiles and susceptibility to complement lysis. We investigated whether complement resistance of Borreliae could be due to acquisition of the main soluble inhibitors of the alternative complement pathway, factor H and the factor H-like protein 1. When exposed to nonimmune EDTA-plasma, the serum-resistant B. afzelii and B. burgdorferi sensu stricto strains bound factor H/factor H-like protein 1 to their surfaces. Assays with radiolabeled proteins showed that factor H bound strongly to the B. burgdorferi sensu stricto strain. To identify factor H ligands on the borrelial surface, we analyzed a panel of outer surface proteins of B. burgdorferi sensu stricto with the surface plasmon resonance technique. The outer surface lipoprotein OspE was identified as a specific ligand for factor H. Using recombinant constructs of factor H, the binding site for OspE was localized to the C-terminal short consensus repeat domains 15-20. Specific binding of factor H to B. burgdorferi sensu stricto OspE may help the pathogen to evade complement attack and phagocytosis.     

Soil Washing Feasibility at a Manufacturing Gas Plant Site

Bench-scale treatability tests were carried out in order to evaluate performances of “physical” soil washing (particle size classification aimed at “concentrating” contamination in the fine fraction of the soil) and of a surfactant-aided soil-washing process on a brownfield soil, contaminated by high-molecular-weight Polycyclic Aromatic Hydrocarbons (PAHs). In the first case, soil was classified by wet particle separation using water, whereas it was extracted by water + surfactant in the second case. The chemical agent was selected among non-ionic synthetic and anionic biogenic surfactants (Triton X-100, Igepal CA-720, Brij-30, JBR 325), evaluating the kinetics of the desorption process and the extraction efficiency for different time of contact with soil. Surfactant concentration was selected by evaluating the extraction efficiency at the optimal time of contact. A surfactant-aided soil-washing process was tested, where soil was sequentially treated by fresh soil-washing solution (water + surfactant), and soil-washing solution was recycled for other contaminated soil. Transfer efficiency of PAHs and recovery of surfactant solution were evaluated