Background/aims: Several randomised controlled trials (RCTs) have raised concerns about potential harm associated with erythropoiesis-stimulating agents (ESAs) in chronic kidney disease patients, especially when haemoglobin (Hb) levels above 13 g/dl were targeted. We report the relationship between Hb levels and outcomes in the methoxy polyethylene glycol-epoetin beta RCT programme.
Methods: We assessed the association between Hb and a composite end point, as well as its components [all-cause mortality, myocardial infarction (MI) or cerebrovascular events (CVE)], in multiple post hoc analyses of 9 prospective RCTs (3,405 chronic kidney disease patients).
This paper describes a microfluidic quenched flow platform for the investigation of ligand-mediated cell surface processes with unprecedented temporal resolution. A roll-slip behavior caused by cell-wall-fluid coupling was documented and acts to minimize the compression and shear stresses experienced by the cell. This feature enables high-velocity (100-400 mm/s) operation without impacting the integrity of the cell membrane.
View Article and Find Full Text PDFSince November 2009, Germany's first full-scale ozonation plant for tertiary treatment of secondary effluent is in continuous operation. A kinetic model was developed and combined with the commercial computational fluid dynamics (CFD) software ANSYS(®) CFX(®) to simulate the removal of micropollutants from secondary effluents. Input data like reaction rate constants and initial concentrations of bulk components of the effluent organic matter (EfOM) were derived from experimental batch tests.
View Article and Find Full Text PDFAn experimental setup for the examination of single bubbles, rising in a liquid, is presented. Its main part is a rotating chamber, in which the bubble is spatially stabilized by a balance of buoyancy, drag, and lift forces. This allows for long observation periods in time.
View Article and Find Full Text PDFWe investigate the electrokinetic flow and transport within a micro-electrophoresis device. A mathematical model is set up, which allows to perform two-dimensional, time-dependent finite-element simulations. The model reflects the dominant features of the system, namely electroosmosis, electrophoresis, externally-applied electrical potentials, and equilibrium chemistry.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
August 2005
Electroosmosis, originating in the double-layer of a small liquid-filled pore (size R) and driven by a voltage V, is shown to be effective in pumping against the capillary pressure of a larger liquid droplet (size B) provided the dimensionless parameter sigmaR(2)/epsilon|zeta|VB is small enough. Here sigma is surface tension of the droplet liquid/gas interface, epsilon is the liquid dielectric constant, and zeta is the zeta potential of the solid/liquid pair. As droplet size diminishes, the voltage required to pump electroosmotically scales as V approximately R(2)/B.
View Article and Find Full Text PDFG-protein-gated inward rectifying potassium channels (GIRKs) are a newly identified gene family. These gene products are thought to form functional channels through the assembly of heteromeric subunits. Recently, it has been demonstrated that a point mutation in the GIRK2 gene, one of the GIRK family members, is the cause of the neurological and reproductive defects observed in the weaver (wv) mutant mouse.
View Article and Find Full Text PDFThere is increasing evidence that nerve growth factor (NGF) acts on cells of the immune system, apart from its neurotrophic effects. In human basophils, NGF potentiates mediator release and primes the cells to produce leukotriene C4 in response to C5a. It is, however, unknown whether other homologous neurotrophins also act outside the nervous system, and whether activation of basophils by NGF requires interaction with trk tyrosine kinase receptors, the low affinity NGF receptor (LNGFR), or both.
View Article and Find Full Text PDFMycotic aneurysm of the posterior tibial artery and pseudophlebitis: role of color Doppler sonography A case of a 78-year-old male patient presenting with endocarditis caused by Streptococcus bovis and pseudophlebitis of the left lower limb is described. Color Doppler sonography ruled out thrombophlebitis and showed a large pulsatile mass of the posterior compartment of the leg due to a mycotic aneurysm of the posterior tibial artery. This aneurysm was confirmed by angiography and treated by surgery.
View Article and Find Full Text PDFIncreasing evidence indicates that nerve growth factor (NGF), in addition to its neurotrophic actions, exerts specific effects on cells of the immune system. This report show that the CD4-positive T cell line 9/6 expresses trk protooncogene, the signal transducing receptor unit for NGF, after TCR-mediated activation by Ag and APC. This receptor is of functional importance because interaction of NGF with Ag-stimulated 9/6 T cells induced the transcriptional activation of the c-fos gene, a hallmark of the biochemical response to NGF.
View Article and Find Full Text PDFUsing reverse transcription followed by polymerase chain reaction, we examined the expression of mRNA for the tyrosine kinase receptors trk and trkB in rat sensory and sympathetic ganglia during postnatal development. While the levels of both trk and trkB mRNA in the dorsal root ganglia (DRG) decreased two-fold, they increased by seven and two times, respectively, in superior cervical ganglia. The developmentally regulated and tissue-specific expression of trk and trkB genes suggest that peripheral ganglia differ in their responsiveness to neurotrophins in neonatal and adult rats.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
December 1993
Recent evidence suggests that nerve growth factor (NGF), in addition to its neurotrophic functions, acts as an immunomodulator mediating "cross-talk" between neuronal and immune cells, including T lymphocytes. We have analyzed murine CD4+ T-cell clones for their ability to express transcripts encoding NGF, low-affinity NGF receptor, and trk protooncogene, the signal-transducing receptor subunit for NGF. We show that two CD4+ T-helper (Th) clones, Th0-type clone 8/37 and Th2-type clone D10.
View Article and Find Full Text PDFWe have used the human neuroblastoma cell line SH-SY5Y as a model system to investigate the expression and regulation of the receptors for brain-derived neurotrophic factor (BDNF), a member of the nerve growth factor (NGF) family of neurotrophins. We demonstrate that SH-SY5Y cells express transcripts encoding the low-affinity NGF receptor (LNGFR) and trkB, the signal transducing receptor unit for BDNF. Interaction of BDNF with SH-SY5Y cells increased the transcription of the c-fos gene, showing that these molecules encode functional BDNF receptors.
View Article and Find Full Text PDFThere is increasing evidence that neurotrophins, including nerve growth factor (NGF), exert specific effects on cells of the immune system in addition to their neurotrophic actions. This report shows that human monocytes express the trk protooncogene, encoding the signal-transducing receptor unit for NGF. This receptor is functional, since interaction of NGF with monocytes triggered a respiratory burst, the major component of monocyte cytotoxic activity.
View Article and Find Full Text PDFNaunyn Schmiedebergs Arch Pharmacol
September 1990
Using a monoclonal antibody against the human nerve growth factor (NGF) receptor (20.4 IgG), a specific immunoprecipitation assay for the quantitation of human NGF binding sites has been established. The procedure involves specific labeling of NGF receptors by covalent crosslinking to 125I-NGF with a carbodiimide reagent, and subsequent immunoprecipitation of the detergent-extracted 125I-NGF-receptor complexes with the 20.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
December 1989
Nerve growth factor (NGF) is known to affect peripheral sympathetic and sensory neurons as well as defined populations of neurons in the central nervous system. This paper presents evidence that NGF is also active in modulation of B-cell-mediated immune responses. NGF receptors were immunoprecipitated from highly purified human B-cell populations, and to a lesser extent, from T-cell populations, by using a monoclonal antibody recognizing NGF receptors present on neural cells.
View Article and Find Full Text PDFGlial cells have been shown previously to release factors that promote survival of central and peripheral neurons [neuronotrophic factors (NTFs)]. We have investigated the release of NTFs by C6 cells, a rat glioma cell line, under different modes of conditioning. Media conditioned in the presence or absence of serum [C6 cell conditioned media (C6CMs)] were analyzed using biological, biochemical, and immunological assays.
View Article and Find Full Text PDFNaunyn Schmiedebergs Arch Pharmacol
November 1987
In saphenous nerve neuromata of adult rats a long-term increase of immunoreactive nerve growth factor (irNGF) was detected after nerve transection. The occurrence of messenger RNA encoding NGF (NGF mRNA) in these proximal nerve stumps indicates local biosynthesis of NGF. In situ superfusion of neuromata revealed a constant release of irNGF which was significantly reduced by substance P (SP) but not affected by calcitonin gene related peptide (CGRP).
View Article and Find Full Text PDFJ Pharmacol Exp Ther
September 1986
The binding characteristics and pharmacological properties of o-isothiocyanate dihydropyridine [oNCS-DHP; 2,6-dimethyl-3,5-dicarbomethoxy-4-(2-isothiocyanatophenyl)-1, 4-dihydropyridine] were investigated in guinea pig heart and ileum. [3H]oNCS-DHP bound to a single population of high-affinity sites (Bmax = 107 fmol/mg of protein and Kd = 0.99 nM) in cardiac membranes, with a specificity characteristic of dihydropyridine receptors.
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