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Notes: Light emitting devices with a sandwich structure: metal/EC6T/indium-tin-oxide, using end-capped sexithiophene (EC6T) as active organic material were fabricated by vapor deposition. Current and intensity of electroluminescence (EL) of the EC6T layers were measured as a function of voltage for various metals (Ca, Mg, Al, In, Ag) in a wide range of temperatures (4–300 K) and thicknesses of the EC6T layers (40–350 nm). External quantum efficiencies (10−6–10−3) and rectification ratios significantly depend on the metal contact which is compatible with a Schottky barrier. Electron injection from the metal at higher voltages correlates with the onset of significant EL. Current–voltage (I–V) curves exhibit a strong temperature and thickness dependence, mainly due to the charge transport across the EC6T layer. At low temperatures I–V curves show space charge limited currents. Modeling including double injection and trap states is performed. Results are discussed under the aspect of further device optimization. © 1997 American Institute of Physics.

Notes: Abstract The facilities for photon scattering experiments at the Mainz electron linear accelerator are described. They include an energy analyzing system, the bremsstrahlung target and a photon spectrometer (NaI-crystals). The question of background elimination is discussed. The scattered photon spectrum from a carbon target is presented.

Notes: Summary A total of 351 drug-users (127 in-patients of the university hospital for nervous diseases Frankfurt a. Main, 124 out-patients of the special health centre in the city of Frankfurt a. Main) were steadily investigated between the years 1969/70 with the aid of a fixed catalogue consisting of 386 single criterions with quantitative and qualitative alternatives. The informations for instance on the development of the drug-user, his familiar and social situation, sexuality, drug-use, vegetative nervous system, constitution were registered by widely pre-defined lists of data. The psychological investigation was done among other examinations by the modified Hamburg-Wechsler-intelligence-test. Subsequently the facts of the investigation were evaluated with the aid of an electronic computing station; the analysis of the data obtained took place by aspects of statistical correlations. Complementary to our study Hausner investigated in the same way 100 drug-users directly accosted at the so-called “scene”. General characteristics of the drug-users: 80% were aged between 16 and 24 years (just under 25% till 16, 50% till 21, 25% above 25 years). There were each 20% female drug-users among the in- and out-patients, but 40% among the population of the “scene”. Only 3% of all drug-users exclusively took cannabis, just under 50% in addition halluzinogenic drugs, some more than the half opiates too. All drug-users took stimulants, most often the opiate-users; in number: two thirds of the stimulants were taken by them. 60% were addicted or respectively suspected. According to the particular social level there was a special affinity to certain drugs (working people prefered stimulants, pupils and students cannabis and halluzinogenic drugs). University education of the father was dominating at the users of hallucinogenic drugs, half of them became addicted during the time of observation. Opiate-users more often had fathers without university education, they planned their profession more frequently not themselves and had more often a social decline. Social situations of the drug-users: 36% were pupils or students, 12% in vocational training, 8% professional active. 42% pursued no more any job. The so-called “drop-outs” more frequently had stopped going to school or stopped their professional course of education, they planned their profession more often not themselves and their future more seldom longtermed, pupils of secondary schools or students had only an average or even more modest intelligence-quotient. Overstrain and absence of suitable helps for the choice of profession seem to be important factors as to a disadvantageous progress of the drug-career. Only 50% of the drug-users visiting secondary schools or universities had the intelligence-quotient required. The drug-use seems to become encouraged by conflicts concerning high demands standards combined with actual overstrain. 43% of the drug-users had a social decline in comparison with their descent family. Hence follow level-specific endangering patterns to the development of addictions which primary are multidimensional applied. 49% of all drug-users investigated were likely to have a progressive course of their drug-career. This average-probability augmented to 68%, when the parents were left in conflicts, and declined to 40%, when there was a harmonic atmosphere in the parent's house. Only 1% of the drug-users was not impaired in their social connections after a drug-use of 6 months. The following factors were able to inhibit these social detractions: The factor retardation (including a corresponding reaction of the environment) and the factor constitution. Further on it appeared that the taking of drugs in community decreased to 50% in the last 6 months of the drug-use compared with more than 80% in the first half year of the drug-use. That means: The operation of drugs does not lead to the primary intended partner-ship but to a disappearing in the world of own experiences. 19% of the investigated people were criminal before starting the drug-use (special concerning prosperity delicts); after that 52% were criminal, special concerning violations of the narcotic law, 25% of them because of dealing with drugs. In general it is to say that there are to consider interactions for instance between negative social development and drug operation on the central nervous system when analysing the constellations of risks in direction of adverse progresses.

Notes: Summary In 26 patients (aged 43–74 years) polygraphic night sleep recordings, prior to and following long term administration ofl-DOPA, were performed. These results were correlated with the neurological, psychiatric and psychological test findings registered in each patient. There is a correlation between sleep disturbances and clinical symptoms: marked signs of Parkinson's disease are associated with a significant delay in the onset of sleep, prolonged waking periods and a reduction of light synchronous sleep. There are also correlations between pathological results in reaction time and tests of mood and intellectual functions, prolonged time before onset of sleep, longer waking periods and a reduction of REM sleep. Long term administration ofl-DOPA — alone or combined with a decarboxylase inhibitor — causes an increase in REM sleep as well as NREM sleep, corresponding with a marked improvement in the clinical symptoms of Parkinson's disease. This effect ofl-DOPA on sleep is attributed to regained mobility. There is also a specific influence ofl-DOPA on REM sleep, viz., prolongation of REM latency with an REM rebound in the second half of the night. The differentiation of a specific inhibitory effect ofl-DOPA on REM sleep and a nonspecific one on both stages of sleep in Parkinsonian patients may explain the diverse results of many authors. Thus, in patients without motor disability, general effects on the course of sleep with an increase of NREM sleep should not be expected. In such cases the inhibitory effect ofl-DOPA on REM sleep is to be seen, especially when administered just before the onset of sleep. Likewise there was no effect on NREM sleep after a single dose ofl-DOPA in patients in whom there was not already, definite improvement in the clinical signs of parkinsonism, but rather, an inhibitory influence on REM sleep occurred.

Notes: Abstract Analysis of facular contrast ΔI/I qs from Extreme Limb Photometer (ELP) data of the summer of 1983 yield a mean contrast of 0.91 ± 0.19% and 1.57 ± 0.16% for apertures 1 and 2 located at μ= 0.198 and at μ = 0.111, respectively. The ratio of the mean contrast in the outer aperture (closer to the limb) to that of the inner one is 1.71 ± 0.40, indicating an increase in the mean facular contrast toward the limb. This result is in agreement with observations made in 1975, 1979, and 1982. The errors are dominated by the random presence of solar active regions. The combined results from all seasons follow an approximately μ −1 curve. Facular excess solar oblateness signals for 1983 are 33.8 ± 6.6 arc ms and 16.5 ± 2.1 arc ms for ELP apertures 1 and 2, respectively, in reasonable agreement with the 1983 excess solar oblateness results of Dicke, Kuhn, and Libbrecht (1985).

Notes: Abstract Aims/hypothesis. The Karlsburg Type I (insulin-dependent) diabetes risk study on schoolchildren aims to evaluate the predictive diagnostic value of diabetes-associated autoantibodies in the general population. Methods. We took capillary serum from 9419 schoolchildren, aged 6–17 years, for testing of autoantibodies (AAbs) to glutamic acid decarboxylase (GADA), protein tyrosine phosphatase (IA2A) and insulin (IAA) by 125I-antigen binding. We also tested for autoantibodies to cytoplasmic islet cell antigens (ICA) immunohistochemically. Results. By testing of 9419 sera for the four AAbs at cut-off at or greater than the 98th centile for the radioassayed AAbs and at or greater than 10 Juvenile Diabetes Foundation (JDF) units for ICA, 8.1 % of schoolchildren had at least one AAb. We found that 3.04, 2.97, 2.35, and 0.86 % had IAA, GADA, IA2A or ICA, respectively. 7.3 % had only one AAb and 0.8 % (75) had two or more AAbs, reflecting a risk to develop diabetes. Thus, by primary screening by combined testing of GADA and IA2A, 98.7 % (74/75) would be identified. At high AAb levels, cut-off at or greater than the 99.8th centile and at or greater than 40 JDF units for ICA, 0.23 % (22/9419) of schoolchildren, similar to the disease prevalence of 0.3 %, had two or more AAbs. Ten of 17 children tested had reduced (p 〈 0.001) first-phase insulin secretion by intravenous glucose tolerance test. Six of 22 subjects developed Type I diabetes within a follow-up of 19 ± 10 months. Conclusion/interpretation. For children older than 5 years the combined anti-GAD/IA2 test with cut-off at or greater than the 98th centile should be used for primary screening followed by testing for IAA and ICA. Subjects at risk for diabetes have two or more AAbs at or greater than the 98th centile. Subjects at risk for rapid progression to Type I diabetes have two or more AAbs at or greater than the 99.8th centile. [Diabetologia (1999) 42: 661–670]

Notes: Summary The non-specific activation of the immune system by administration of complete Freund's adjuvant was examined in Wistar rats as a possible means of amplification of the specific immune response directed to pancreatic β cells caused by low dose non-diabetogenic multiple injections of streptozotocin. Rats were given intraperitoneally 0.5 ml of complete Freund's adjuvant to induce polyclonal lymphocyte activation and, 1 day later, the animals were given an intraperitoneal injection of 15 mg streptozotocin/kg body weight (group 1). This combined treatment was given twice at weekly intervals. In two further groups, rats were treated with complete Freund's adjuvant alone (group 2) or streptozotocin alone (group 3) with the same doses and at the same times. Only the rats in group 1 developed delayed but severe and persistent hyperglycaemia. In addition, significant complement-dependent cytotoxicity was detected in nine out of 15 rats (60%) in group 1 in islet cells, but not in spleen lymphocytes. The pancreatic insulin content of the rats in group 1 was depleted by up to 3.1 ± 0.5%. With these experiments, a new animal model for insulin-dependent diabetes is described; complete Freund's adjuvant/streptozotocin diabetes. In many aspects, this model of diabetes parallels the development of insulin-dependent diabetes in man, including the humoral autoimmunity to islet cell antigens.

Notes: Summary Eleven patients with Huntington's disease were treated with high doses of isoniazid. In addition to the clinical assessment, the functional capacity was evaluated quantitatively. The symptoms of four of the patients showed a marked improvement and their functional capacity increased. The condition of one patient with the rigid form (Westphal's variant) deteriorated, and the remaining six patients showed no change. Patients with prominent mental disturbances appeared to respond best to isoniazid therapy.

Notes: Abstract To study the immune response to glutamic acid decarboxylase (GAD) in insulin-dependent diabetes mellitus, monoclonal GAD antibodies after fusion of splenocytes from a nondiabetes-susceptible BALB/c mouse immunized with human recombinant GAD65 were generated. Of the 44 monoclonals, 35 are specific for the GAD65 isoform, whereas 9 also react with GAD67. Some 37 monoclonals, including all GAD65/67 reactive antibodies, react with GAD by Western blot analysis. The remaining 7 GAD65 monoclonals bind GAD only in an immunoprecipitation assay, which implies that they target epitopes dependent on the conformation of the GAD molecule. The125I-GAD binding of the GAD65 monoclonals reactive on Western blotting was significantly diminished by all 3 sera from Stiff-man syndrome patients but only by 3/30 (10%) sera from type 1 diabetic patients. In contrast, the 7 monoclonal antibodies reactive with a conformation-dependent GAD epitope were competitive with 83% of GAD-autoantibody-positive sera from these diabetic patients. Using chimeric GAD65/67 proteins, the epitope region targeted by these monoclonals was mapped to the middle of GAD65 (amino acids 221–442). This central conformation-dependent GAD region was also targeted by sera from patients with type 1 diabetes. In conclusion, our data show that evne after common immunization of a nondiabetes-susceptible mouse strain, monoclonals were obtained which preferentially react with the GAD65 linear amino-terminus (amino acids 4–17) and a conformation-dependent region located in the middle of GAD targeted by autoantibodies, indicating that this GAD region is not restricted to the autoimmune response associated with the Stiff-man syndrome and the bete-cell destruction in type 1 diabetes mellitus.

Notes: Abstract The influence of beta cell activity on cytokineinduced functional and structural impairments as well as the ability of those damaged cells to recover were investigated. Rat islets cultured for 4 days in the presence of 5, 10, and 30 mmol/l glucose were exposed to interferon-γ (IFN, 500 U/ml) and tumor necrosis factor-α (TNF, 250 U/ml) for the last 24 h. After cytokine removal islets were allowed to recover spontaneously in culture medium containing 10 mmol/l glucose for a further 7 days. Cytokines significantly inhibited insulin release into culture medium, insulin storage, glucose-stimulated insulin secretion, protein, and DNA synthesis. In the presence of cytokines there was a six- to eightfold increase in nitrite production by the islets. The functional impairments were more pronounced in metabolically stimulated beta cells. In addition, cytokines caused membrane alterations as indicated by increased spontaneous chromium-51 release. The cytokines specifically induced the synthesis of two proteins (72 and 88 kDa, respectively). By immunoblotting, the 72-kDa protein was identified as heat shock protein. After a 1-week recovery period, insulin storage and stimulated insulin secretion of cytokine-treated islets were still significantly diminished. However, protein and DNA synthesis of cytokine-exposed islets returned to pre-exposure levels. In conclusion, high beta cell activity increases islet susceptibility to TNF+IFN. Cytokine-induced, longlasting, inhibitory effects are primarily directed to betacell-specific functions, while general vital cell functions clearly recover after cytokine removal. The induction of certain proteins and the increased protein synthesis and replication rate after cytokine removal might reflect activated repair processes.