Trennung von Tocopherolen und Tocotrienolen durch HPLC

HPLC Separation of Tocopherols and Tocotrienols The four tocopherols (T) and four tocotrienols (T3) as well as plastochromanol-8 (P-8) and BHA were separated completely by eluting them from a HPLC diol-column with n-hexane/methyl tert-butylether (96 : 4, v/v). Even for the β- and γ-tocopherol and -tocotrienol isomers, baseline separation was achieved. The method was verified. The method was verified with success on several plant seed oils which were injected directly without any clean-up. For cereals a simplified extraction method was developed and the T, T3 and P-8 content of 9 cereal crops was determined. The separation system showed a long-term stability over six month.     

An explicit immunogenetic model of gastrointestinal nematode infection in sheep

Gastrointestinal nematodes are a global cause of disease and death in humans, wildlife and livestock. Livestock infection has historically been controlled with anthelmintic drugs, but the development of resistance means that alternative controls are needed. The most promising alternatives are vaccination, nutritional supplementation and selective breeding, all of which act by enhancing the immune response. Currently, control planning is hampered by reliance on the faecal egg count (FEC), which suffers from low accuracy and a nonlinear and indirect relationship with infection intensity and host immune responses. We address this gap by using extensive parasitological, immunological and genetic data on the sheep–Teladorsagia circumcincta interaction to create an immunologically explicit model of infection dynamics in a sheep flock that links host genetic variation with variation in the two key immune responses to predict the observed parasitological measures. Using our model, we show that the immune responses are highly heritable and by comparing selective breeding based on low FECs versus high plasma IgA responses, we show that the immune markers are a much improved measure of host resistance. In summary, we have created a model of host–parasite infections that explicitly captures the development of the adaptive immune response and show that by integrating genetic, immunological and parasitological understanding we can identify new immune-based markers for diagnosis and control.     

Stormwater and fire as sources of black carbon nanoparticles to Lake Tahoe

Emitted to the atmosphere through fire and fossil fuel combustion, refractory black carbon nanoparticles (rBC) impact human health, climate, and the carbon cycle. Eventually these particles enter aquatic environments, where they may affect the fate of other pollutants. While ubiquitous, the particles are still poorly characterized in freshwater systems. Here we present the results of a study determining rBC in waters of the Lake Tahoe watershed in the western United States from 2007 to 2009. The study period spanned a large fire within the Tahoe basin, seasonal snowmelt, and a number of storm events, which resulted in pulses of urban runoff into the lake with rBC concentrations up to 4 orders of magnitude higher than midlake concentrations. The results show that rBC pulses from both the fire and urban runoff were rapidly attenuated suggesting unexpected aggregation or degradation of the particles. We find that those processes prevent rBC concentrations from building up in the clear and oligotrophic Lake Tahoe. This rapid removal of rBC soon after entry into the lake has implications for the transport of rBC in the global aquatic environment and the flux of rBC from continents to the global ocean.     

LAIR1, an ITIM-Containing Receptor Involved in Immune Disorders and in Hematological Neoplasms

Leukocyte-associated immunoglobulin (Ig)-like receptor 1 (LAIR1, CD305) belongs to the family of immune-inhibitory receptors and is widely expressed on hematopoietic mature cells, particularly on immune cells. Four different types of ligands of LAIR1 have been described, including collagens, suggesting a potential immune-regulatory function on the extracellular matrix. By modulating cytokine secretion and cellular functions, LAIR1 displays distinct patterns of expression among NK cell and T/B lymphocyte subsets during their differentiation and cellular activation and plays a major negative immunoregulatory role. Beyond its implications in physiology, the activity of LAIR1 can be inappropriately involved in various autoimmune or inflammatory disorders and has been implicated in cancer physiopathology, including hematological neoplasms. Its action as an inhibitory receptor can result in the dysregulation of immune cellular responses and in immune escape within the tumor microenvironment. Furthermore, when expressed by tumor cells, LAIR1 can modulate their proliferation or invasion properties, with contradictory pro- or anti-tumoral effects depending on tumor type. In this review, we will focus on its role in normal physiological conditions, as well as during pathological situations, including hematological malignancies. We will also discuss potential therapeutic strategies targeting LAIR1 for the treatment of various autoimmune diseases and cancer settings.     

In Vitro Rescue of the Bile Acid Transport Function of ABCB11 Variants by CFTR Potentiators

ABCB11 is responsible for biliary bile acid secretion at the canalicular membrane of hepatocytes. Variations in the ABCB11 gene cause a spectrum of rare liver diseases. The most severe form is progressive familial intrahepatic cholestasis type 2 (PFIC2). Current medical treatments have limited efficacy. Here, we report the in vitro study of Abcb11 missense variants identified in PFIC2 patients and their functional rescue using cystic fibrosis transmembrane conductance regulator potentiators. Three ABCB11 disease-causing variations identified in PFIC2 patients (i.e., A257V, T463I and G562D) were reproduced in a plasmid encoding an Abcb11-green fluorescent protein. After transfection, the expression and localization of the variants were studied in HepG2 cells. Taurocholate transport activity and the effect of potentiators were studied in Madin–Darby canine kidney (MDCK) clones coexpressing Abcb11 and the sodium taurocholate cotransporting polypeptide (Ntcp/Slc10A1). As predicted using three-dimensional structure analysis, the three variants were expressed at the canalicular membrane but showed a defective function. Ivacaftor, GLP1837, SBC040 and SBC219 potentiators increased the bile acid transport of A257V and T463I and to a lesser extent, of G562D Abcb11 missense variants. In addition, a synergic effect was observed when ivacaftor was combined with SBC040 or SBC219. Such potentiators could represent new pharmacological approaches for improving the condition of patients with ABCB11 deficiency due to missense variations affecting the function of the transporter.     

MECHANICAL INTRODUCTION OF BARIUM TO CLAY BODIES1

Several methods of introducing barium to clay bodies are discussed. These include addition (1) in a wet dilute solution, (2) in a wet concentrated solution, (3) dry by sprinkling on to the raw clay in the car before grinding. (4) dry to the dry pan or crusher in proportion to the speed of the machine. (5) dry from a disk feeder applying the clay to the pug mill.     

Functional interactions of genes mediating convergent extension, knypek and trilobite, during the partitioning of the eye primordium in zebrafish

Vertebrate eye development in the anterior region of the neural plate involves a series of inductive interactions dependent on the underlying prechordal plate and signals from the midline of the neural plate, including Hedgehog. The mechanisms controlling the spatiotemporal expression pattern of hedgehog genes are currently not understood. Cyclopia is observed in trilobite (tri) and knypek (kny) mutants with affected convergent extension of the embryonic axis during gastrulation. Here, we demonstrate that tri mutants show a high frequency of partial or complete cyclopia, kny mutants exhibit cyclopia infrequently, while knym119 trim209 double-mutant embryos have dramatically reduced convergent extension and are completely cyclopic. We analyzed the relationships between the convergent extension defect, the expression of hedgehog and prechordal plate genes, and the formation of cyclopia in knym119 and trim209 mutants. Our results correlate the cyclopia phenotype with the abnormal location of hh-expressing cells with respect to the optic primordium. We show that cyclopia in these mutants is not due to an incompetence of tri and kny cells to respond to Hedgehog signaling. Rather, it is a consequence of exceeding a critical distance (>40-50 micrometer) between hedgehog-expressing cells and the prospective eye field. We hypothesize that at this distance, midline cells are not in an appropriate position to physically separate the eye field and that HH and other signals do not reach the appropriate target cells. Furthermore, tri and kny have overlapping functions in establishing proper alignment of the anterior neural plate and midline cells expressing shh and twhh genes when the partitioning of the eye primordium takes place.     

Assessment of cerebral blood flow and CO2 reactivity after controlled cortical impact by perfusion magnetic resonance imaging using arterial spin-labeling in rats

We measured CBF and CO2 reactivity after traumatic brain injury (TBI) produced by controlled cortical impact (CCI) using magnetic resonance imaging (MRI) and spin-labeled carotid artery water protons as an endogenous tracer. Fourteen Sprague-Dawley rats divided into TBI (CCI; 4.02 +/- 0.14 m/s velocity; 2.5 mm deformation), sham, and control groups were studied 24 hours after TBI or surgery. Perfusion maps were generated during normocarbia (Paco2 30 to 40 mm Hg) and hypocarbia (PaCO2 15 to 25 mm Hg). During normocarbia, CBF was reduced within a cortical region of interest (ROI, injured versus contralateral) after TBI (200 +/- 82 versus 296 +/- 65 mL.100 g-1.min-1, P < 0.05). Within a contusion-enriched ROI, CBF was reduced after TBI (142 +/- 73 versus 280 +/- 64 mL.100 g-1.min-1, P < 0.05). Cerebral blood flow in the sham group was modestly reduced (212 +/- 112 versus 262 +/- 118 mL.100 g-1.min-1, P < 0.05). Also, TBI widened the distribution of CBF in injured and contralateral cortex. Hypocarbia reduced cortical CBF in control (48%), sham (45%), and TBI rats (48%) versus normocarbia, P < 0.05. In the contusion-enriched ROI, only controls showed a significant reduction in CBF, suggesting blunted CO2 reactivity in the sham and TBI group. CO2 reactivity was reduced in the sham (13%) and TBI (30%) groups within the cortical ROI (versus contralateral cortex). These values were increased twofold within the contusion-enriched ROI but were not statistically significant. After TBI, hypocarbia narrowed the CBF distribution in the injured cortex. We conclude that perfusion MRI using arterial spin-labeling is feasible for the serial, noninvasive measurement of CBF and CO2 reactivity in rats.