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Notes: Abstract: The time course of changes in the tissue impedance and the levels of extracellular transmitter and non-transmitter amino acids was studied in the striatum and hippocampus of the unanesthetized rat after cardiac arrest. Electrodes were implanted for the continuous measurement of tissue impedance so that a measure of the volume of extracellular space was provided. Alternatively, bilateral dialysis probes were used for monitoring levels of extracellular amino acids in subsequent 30-s samples using an automated precolumn derivatization technique for reversed-phase HPLC analysis and fluorimetric detection. The impedance started to rise ∼1.2 min following cardiac arrest, increased rapidly during the first 5 min, and increased almost linearly thereafter. After 15 min, a decrease of ∼50% in the extracellular space was calculated. The impedance rose more steeply in the striatum than in the hippocampus. The extracellular levels of taurine, which increased 〉300% within 5 min after cardiac arrest, most closely resembled the time course of the change in impedance. Glutamate and aspartate levels did not increase until 5 min after circulatory arrest, and at 15 min they had risen to a level of 465 and 265% for the striatum and 298 and 140% for the hippocampus of the resting release, respectively. The release of γ-aminobutyric acid (GABA) was multiphasic and did not resemble that of any of the other—putative—transmitter amino acids. Fifteen minutes after cardiac arrest, the levels of GABA were 617 and 774% of the resting release in the striatum and hippocampus, respectively. Glycine and ala-nine efflux substantially increased (232 and 151% in striatum and 141 and 154% in hippocampus, respectively) 15 min postmortem, whereas the glutamine level was slightly increased and levels of asparagine, histidine, threonine, ethanolamine, serine, arginine, and tyrosine were inconsistently higher in the two brain regions. At this time, the extracellular levels of glutamate, GABA, and aspartate were only slightly lower, as expected from the tissue levels and from levels of the other amino acids, an observation indicating that all the amino acids may diffuse through postmortem brain tissue to a nearly similar extent. This study provides evidence that extracellular levels of taurine reflect changes in distribution of electrolytes (and in membrane potentials), that the postmortem release of transmitter amino acids is multiphasic with a delay of at least 1 min, that postmortem shrinkage in extracellular volume cannot account for the increase in the content of transmitter amino acids in the dialysate, and that the massive overflow of glutamate, aspartate, GABA, and taurine seen during ischemia is the result of both release and the failure of uptake. Possible implications of the present findings for excitotoxic damage of the brain are discussed.

Notes: We present measurements on multichannel acceleration of intense, low-energy ion beams with a multiple electrostatic quadrupole array linear accelerator. The beam properties are investigated for different transverse and longitudinal focusing strengths, which can be adjusted independently in the accelerator. A maximum He+ ion current of four times 2 mA has been accelerated from 40 to 115 keV with an acceleration efficiency of 50%. Measurements and computer simulations suggest that the current is limited by transverse fields and by mismatch and misalignment of the beams, whereas longitudinal fields are of minor importance. The energy spread in the bunches is roughly three times the gap voltage.

Notes: Bone marrow derived stromal cells are of mesenchymal origin and precursor cells for skeletal tissue components such as chondroblasts and osteoblasts. Furthermore, under experimental conditions, a differentiation potency into myogenic and neuronal cells could be demonstrated. Because of their multipotency these cells represent a population of non-haematogen stem cells that can be regarded as an alternative to human embryonic stem cells for future autologous cell replacement therapies. For a closer look at the differentiation capacity of these cells, rat and human bone marrow stromal cells were isolated from the femur bone and kept in the cell culture applying different cultivation protocols. In a cultivation medium with a serum content of 20%, the majority of these cells express a variety of neuronal markers such as ß-III Tubulin and NeuN as well as the astrocyte marker GFAP, while a minority of about 20% express the marker for neural precursor cells nestin. Cultivation in a chemically defined serum free medium results in the differentiation of a markedly higher percentage of nestin positive neural precursor-like cells. Using bFGF in combination with B27 these cells can be forced to form three dimensionally organized spheres. In order to elucidate a possible therapeutical potency of the bone marrow derived cells the synthesis of neurotrophic factors such as BDNF and NGF were analysed using the ELISA technique. Furthermore, they can be infected using a third generation adenoviral vector with high efficiency and show migratory activity in vitro. After injection of bone marrow derived mesenchymal stem cells into the lateral ventricle of adult rats they adhere to the ependymocytes and pass the ependymal barrier in order to settle in the subventricular space.

Notes: Brain injury remains a significant and potentially devastating outcome of cardiopulmonary bypass (CPB) under circulatory arrest. These outcomes caused by a microvasculature embolization are associated with increased mortality, longer hospital stays and increased use of intermediate or long term care facilities. The administration of heparin in heart surgery during deep hypothermic cardiopulmonary bypass is the basic prophylactic strategy for reducing or even preventing, microvasculature embolization. Unfortunately, an incidence of neuropsychological impairments (NPI) is found in as many as 25 % of the survivors. As it is suspected that these impairments are correlated with morphological alterations, in our study we use the GP IIb-IIIa receptor blocker Eptifibatide for the inhibition of platelet aggregation, in order to look for a reduction of tissue damage compared to the standard treatment. Two groups of 11 piglets (mean body weight of 15±5 kg) underwent 10-minute normothermic bypass, 40-minute cooling on cardiopulmonary bypass, 60-minutes deep hypothermic circulatory arrest (DHCA) at 15°C, and 40-minute rewarming to 37°C. Group 1 was treated only with unfractionated heparin (UFH), whereas Group 2 was medicated with Eptifibatide, in addition to the UFH-treatment group 1. After rewarming, all animals underwent bilateral carotid perfusion with 4% paraformaldehyde. Histological investigations of semi thin sections reveal a marked decrease of hippocampal alterations by using the GP IIb-IIIa receptor blocker in addition to standard UFH treatment. We detect a reduction of degenerative areas in perivascular (vessels with 10–30 μm in diameter) tissue. These semi-quantitative data are confirmed by ultrastructural findings.

Notes: Zusammenfassung Die Geschmacksdifferenz für Phenylthiocarbamid, einMendelsches Merkmal, dessen Erbweise durch umfangreiche Untersuchungen größerer Bevölkerungsgruppen sowie durch Zwillings- und Familienuntersuchungen gesichert und bekannt ist, wird bedingt durch ein Genpaar Gg. Die Anwesenheit von G bedingt den bitteren Geschmack für Phenylthiocarbamid: Gg oder GG. Bei Abwesenheit von G wird Phenylthiocarbamid als geschmacklos empfunden: gg. Die gerichtsmedizinische Bedeutung ergibt sich aus der Tatsache, daß aus einer Elternverbindung, in der beide Phenylthiocarbamid nicht schmecken, nur nichtschmeckende Kinder zu erwarten sind. Die wenigen bisher bekannten Ausnahmen lassen sich entweder durch Fehlbestimmungen oder bei Familienuntersuchungen durch Illegitimität erklären. Bei der gerichtsmedizinischen Bestimmung der Geschmacksdifferenz für Phenylthiocarbamid ist zu berücksichtigen: a) Es sollen gleichzeitig und kreuzweise Kontrollbestimmungen mit abgestuften Lösungen von Chininsulfat und Saccharin so durchgeführt werden, daß die zu untersuchende Person nicht weiß, welche Substanz geprüft wird. b) Eine Ermüdung ist durch längere Pausen während der Untersuchung zu vermeiden. c) Die Bestimmung ist vor dem 6. Lebensjahre unsicher und deshalb nicht auswertbar. d) Es bestehen Unterschiede in der Empfindlichkeit für Phenylthiocarbamid auf der rechten und linken Zungenseite. e) Es kann schwierig Sein, schwache Schmecker sicher von Nichtschmeckern abzugrenzen. f) Bei lokalen Erkrankungen der Mundhöhle, Zahnlosigkeit, künstlichem Zahnersatz einschließlich großen Metallbrücken ist ebenso wie bei Allgemein- oder Nervenerkrankungen aus Sicherheitsgründen das Merkmal nicht verwertbar, vor allem, wenn es um die Bestimmung eines Nichtschmeckers geht. Der Ausschluß eines bestimmten Mannes allein auf Grund der Geschmacksdifferenz gegen Phenylthiocarbamid, theoretisch möglich, sollte praktisch, wenigstens vorläufig, nicht ausgesprochen werden, außer wenn durch weitere Merkmale die Erzeugerschaft unwahrscheinlich ist. Die Entdeckung weiterer genabhängiger Geschmacksdifferenzen eröffnet gerichtsmedizinisch neue Ausschlußmöglichkeiten.

Notes: Zusammenfassung Es wird eine einfache Methode der Dünnschichtchromatographie in Glasröhren (Tubes) mit folgenden Vorteilen beschrieben: 1. Durch die exakte Einstellbarkeit des Wassergehaltes der Schicht sind die Rf-Werte besser als mit den bisher üblichen Methoden reproduzierbar. 2. Die vorgefertigten beschichteten Röhrchen (inaktive Tubes) ermöglichen, bei verschiedenen Temperaturen aktiviert, die Auswahl jeweils günstigster Trennungsbedingungen. 3. Die standardisierten Bedingungen erlauben den unmittelbaren Vergleich der Ergebnisse verschiedener Untersuchungen. Die beschichteten, aktivierten und lufttrockenen tubes sowie das nötige Zubehör können jetzt von C. Desaga (Heidelberg) bezogen werden.

Notes: Abstract Lambda hyperons fromv p and $$\bar v$$ p charged current interactions have been analysed for polarization. A significant polarization is observed for Λ particles in the quasi-elastic region for both types of interactions. Part of this polarization is due to the decay of highly polarized Σ(1385) resonances. The results are compared with simple predictions of the quark parton model.