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Notizen: In previous works, the size-consistent self-consistent matrix dressing method has been applied to single reference as well as to complete active space singles and doubles configuration interaction. The wave function of the dressed state was assumed to be dominated by a closed shell determinant. Here, the method has been extended to systems where the dressed state is a single-configurational doublet. The method allows for the accurate calculation of energies and wave functions of other electronic states of the same system, having or not the same symmetry, as well as in the case of closed shell systems. This statement has been thoroughly assessed by the calculation of vertical ionization energies corresponding to a few low lying states of HF+ that are compared to full CI results obtained with the cc-pVDZ basis set. The method has been applied, using larger basis sets, to the calculation of vertical ionization potentials (VIP) of HF, H2CO, N2, and NH3. The results are compared to experimental VIP values. The effects of selecting different CAS spaces and using pseudonatural adapted MO's obtained from the CASSCF matrix densities are shown and discussed. Mean absolute error (MAE) for the calculated states is about 0.07 eV. The difficulties to improve this precision limit are shown. However, the mean signed absolute errors, that measure accuracy, can be made smaller. Small MAE can be obtained using simultaneously VTZ basis sets and intermediate levels of calculation. The possibility of this effect to be assigned to a fortuitous cancellation of errors is pointed out. © 2000 American Institute of Physics.

Notizen: The clinical features of idiopathic stabbing headache (“jabs and jolts syndrome”) were studied in 38 patients who were diagnosed throughout a 1-year period. Mean age at the onset of symptoms was 47.1 years ± 14.5 (SD), and a clear female preponderance was demonstrated (female/male ratio=6.6), Painful attacks were ultrashort, i.e. virtually all attacks in more than two thirds of cases lasted only one second. The frequency of attacks varied immensely, ranging from 1 attach per year to 50 attacks daily. The pain paroxysms usually occurred with an irregular or sporadic temporal pattern. The localization of painful attacks was reported frequently as unifocal, usually in the orbital area, but also multifocal patterns were observed, the attacks frequently changing location from one area to the next. The majority of attacks occurred spontaneously, and accompanying phenomena were reported only rarely. Indomethacin treatment (75 mg daily) seemed to have a complete or partial effect in most patients treated as such (n = 17).

Notizen: Abstract: Recent studies have shown that the pharmacologicaltolerance observed after prolonged exposure to synthetic or plant-derivedcannabinoids in adult rats is accompanied by down-regulation/desensitizationof brain cannabinoid receptors. However, no evidence exists on possiblechanges in the contents of the endogenous ligands of cannabinoid receptors inthe brain of cannabinoid-tolerant rats. The present study was designed toelucidate this possibility by measuring, by means of isotope dilution gaschromatography/mass spectrometry, the contents of both anandamide(arachidonoylethanolamide; AEA) and its biosynthetic precursor,N-arachidonoylphosphatidylethanolamine (NArPE), and2-arachidonoylglycerol (2-AG) in several brain regions of adult male ratstreated daily with Δ9-tetrahydrocannabinol(Δ9-THC) for a period of 8 days. The areas analyzed includedcerebellum, striatum, limbic forebrain, hippocampus, cerebral cortex, andbrainstem. The same regions were also analyzed for cannabinoid receptorbinding and WIN-55,212-2-stimulatedguanylyl-5′-O-(γ-[35S]thio)-triphosphate([35S]GTPγS) binding to test the development of the wellknown down-regulation/desensitization phenomenon. Results were as follows: Asexpected, cannabinoid receptor binding and WIN-55,212-2-stimulated[35S]GTPγS binding decreased in most of the brain areas ofΔ9-THC-tolerant rats. The only region exhibiting no changesin both parameters was the limbic forebrain. This same region exhibited amarked (almost fourfold) increase in the content of AEA after 8 days ofΔ9-THC treatment. By contrast, the striatum exhibited adecrease in AEA contents, whereas no changes were found in the brainstem,hippocampus, cerebellum, or cerebral cortex. The increase in AEA contentsobserved in the limbic forebrain was accompanied by a tendency of NArPE levelsto decrease, whereas in the striatum, no significant change in NArPE contentswas found. The contents of 2-AG were unchanged in brain regions fromΔ9-THC-tolerant rats, except for the striatum where they dropped significantly. In summary, the present results show that prolonged activation of cannabinoid receptors leads to decreased endocannabinoid contents and signaling in the striatum and to increased AEA formation in the limbic forebrain. The pathophysiological implications of these findings are discussed in view of the proposed roles of endocannabinoids in the control of motor behavior and emotional states.

Notizen: Six isolates of plum pox potyvirus from different Mediterranean countries were compared by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), peptide mapping and Western blotting after improved purification of virions using a protease inhibitor cocktail that reduced coat protein degradation. One isolate (Spanish isolate 3.3 from plum) differed from the others in possessing a smaller coat protein (approximately 34 instead 36 kDa) with a possible deletion in the surface-exposed amino-terminal region. Infectivity of the viruses after proteolysis, assessed using a local lesion host, was significantly reduced. Protease digestion conditions were established to generate a 28 kDa resistant core of the viral coat protein. Such conditions (longer incubation times or an increase in the enzyme concentration) differed from the milder ones reported for other potyviruses. Implications of the results in relation to the production and screening of virus-specific monoclonal antibodies are discussed.

Notizen: Abstract The environment has emerged as an important determinant of the performance of the modern chemical industry. This paper reviews approaches for incorporating environmental issues into the design of new processes and manufacturing facilities. The organizational framework is the design process itself, which includes framing the problem and generating, analyzing, and evaluating alternatives. A historical perspective on the chemical process synthesis problem illustrates how both performance objectives and the context of the design have evolved to the point where environmental issues must be considered throughout the production chain. In particular, the review illustrates the need to view environmental issues as part of the design objectives rather than as constraints on operations. A concluding section identifies gaps in the literature and opportunities for additional research.

Notizen: A case of circle hairs is reported and the literature on the subject reviewed. Differential diagnoses are discussed as well as some theories on the nature of circle hairs.

Notizen: The responsiveness of prolactin release to regulatory inputs depends on the functional state of the lactotrophs. In the present study, we have examined the effects of luteinizing hormone-releasing hormone (LHRH; 10–7 or 10–6 M) on the release of prolactin in vitro from hyperplastic pituitaries of estrogen-treated male Fischer rats, ectopic pituitary transplants and in situ pituitaries of grafted and control rats. The effects of dopamine (10–8 or 10–7 M) in this system were also examined. The extent of inhibition of prolactin release by dopamine was not related to the amounts of prolactin secreted under basal conditions or to plasma prolactin levels. LHRH significantly suppressed prolactin secretion in all groups but its effect was most pronounced in the ectopic pituitary transplants and in the hyperplastic pituitaries of animals after chronic exposure to estrogen followed by a period of recovery. Thus, the effects of LHRH on prolactin release appear to be related to the secretory activity and/or to the absolute or relative number of the lactotrophs.