Pentobarbital—Ein Abbauprodukt von Thiopental

Journal of Molecular Medicine -     

ADULT-syndrome: An autosomal-dominant disorder with pigment anomalies,ectrodactyly, nail dysplasia,and hypodontia

We describe a family with at least seven living persons who are affected by an hitherto undescribed autosomal-dominant syndrome with variable expression, bearing close resemblance to the EEC syndrome and related disorders. The main manifestations are hypodontia and/or early loss of permanent teeth, ectrodactyly, obstruction of lacrimal ducts, onychodysplasia, and excessive freckling. We propose the acronym ADULT (acro-der-mato-ungual-lacrimal-tooth)-syndrome for this condition. © 1993 Wiley-Liss, Inc.     

The effect of sodium ions on the light-induced86Rb release from the isolated crayfish retina

The effect of low external Na⁺ concentrations on the light-induced K⁺ release from crayfish photoreceptor cells was tested by labelling intracellular K⁺ with the isotope⁸⁶Rb. The amount of isotope released per light stimulus is roughly proportional to the external Na⁺ concentration if the osmolarity is kept constant by replacing Na⁺ with Tris, choline or sucrose. When sucrose is used to replace the depleted Na⁺ the light-induced K⁺ release is a linear function of the external Na⁺ concentration and is reduced by approx. 95% at an external Na⁺ concentration of 5 mmol/l. For choline and Tris substitutions the relationships are less clear but at Na⁺ concentrations 56 mmol/l it seems that in comparison with sucrose the light-induced K⁺ release is smaller in a Tris solution and larger in a choline solution. It is suggested that the light-induced K⁺ release is due mainly to an activation of voltage sensitive K⁺ channels.     

Effects of cyclosporin A on the immune system of the mouse. I. Evidence for a direct selective effect of cyclosporin A on B cells responding to anti-immunoglobulin antibodies

Previous in vivo studies have shown that the immunsuppressive peptide cyclosporin A (CsA) selectively suppresses antibody responses to nonmitogenic T-independent (TI-2) antigens, but not those to mitogenic (TI-1) antigens. This report demonstrates that in vitro CsA suppresses the polyclonal proliferative response of B cells to anti-Ig (anti-mu) antibodies at 300-400 fold lower doses than are required to inhibit B cell proliferation induced by lipopolysaccharide. Since the proliferative response to anti-mu requires neither T cells nor macrophages, it is concluded that CsA has a direct inhibitory effect on the B cells responding to this mitogen. The data support the concept that the B cells responding to TI-2 antigens are contained within the population which is stimulated polyclonally by anti-mu, and that lipopolysaccharide stimulates a distinct B cell subpopulation. They do not, however, exclude the possibility that anti-mu and lipopolysaccharide stimulate the same B cell population via two biochemically distinct triggering mechanisms, one of which is CsA-sensitive and the other CsA-resistant.     

Cardiomyopathy associated with Leigh's disease

Summary Clinical and postmortem findings in a female infant, suffering from Leigh's disease and cardiomegaly are described. The cardiac enlargement was due to symmetrical thickening of both ventricular walls and the septum. On light microscopy a widespread fibre disarray with a slight predilection for the ventricular septum was observed. Ultrastructural changes included an extreme reduction in the number of myofibrils and an excess of mitochondria. Abnormalities of the mitochondrial structure with tubular and myelinic transformation of the cristae suggested that a mitochondriopathy is responsible for the cardiomegaly in Leigh's disease.Dedicated to Prof. Dr. Waldemar Hort on the occasion to his 60th birthday     

Novel KChIP2 isoforms increase functional diversity of transient outward potassium currents

Kv4.3 channels conduct transient outward K⁺ currents in the human heart and brain where they mediate the early phase of action potential repolarization. KChIP2 proteins are members of a new class of calcium sensors that modulate the surface expression and biophysical properties of Kv4 K⁺ channels. Here we describe three novel isoforms of KChIP2 with an alternatively spliced C-terminus (KChIP2e, KChIP2f) or N-terminus (KChIP2g). KChIP2e and KChIP2f are expressed in the human atrium, whereas KChIP2g is predominantly expressed in the brain. The KChIP2 isoforms were coexpressed with Kv4.3 channels in Xenopus oocytes and currents recorded with two-microelectrode voltage-clamp techniques. KChIP2e caused a reduction in current amplitude, an acceleration of inactivation and a slowing of the recovery from inactivation of Kv4.3 currents. KChIP2f increased the current amplitude and slowed the rate of inactivation, but did not alter the recovery from inactivation or the voltage of half-maximal inactivation of Kv4.3 channels. KChIP2g increased current amplitudes, slowed the rate of inactivation and shifted the voltage of half-maximal inactivation to more negative potentials. The biophysical changes induced by these alternatively spliced KChIP2 proteins differ markedly from previously described KChIP2 proteins and would be expected to increase the diversity of native transient outward K⁺ currents.     

Temperature dependence of M pilus formation as demonstrated by electron microscopy

The formation of IncM plasmid encoded pili is dependent on the incubation temperature of the corresponding host strains. By labelling the short, rigid M pili with the donor specific bacteriophage luminal diameter M, the presence of pili at 30 degrees C but not at 37 degrees C incubation temperature could be demonstrated for E. coli K12 substrains carrying different IncM group plasmids. In contrast, such a temperature dependence of M pilus formation is not observed in S. typhimurium substrains.