Ischemic preconditioning phosphorylates mitogen-activated kinases and heat shock protein 27 in the diabetic rat heart

Diabetes mellitus blocks protection by ischemic preconditioning (IPC), but the mechanism is not known. We investigated the effect of ischemic preconditioning on mitogen-activated protein kinases (extracellular signal-regulated kinases 1 and 2, c-Jun N-terminal kinases, p38 mitogen-activated kinase) and heat shock protein 27 phosphorylation in diabetic and nondiabetic rat hearts in vivo. Two groups of anaesthetized nondiabetic and diabetic rats underwent a preconditioning protocol (3 cycles of 3 min coronary artery occlusion and 5 min of reperfusion). Two further groups served as untreated controls. Hearts were excised for protein measurements by Western blot. Four additional groups underwent 25 min of coronary occlusion followed by 2 h of reperfusion to induce myocardial infarction. In these animals, infarct size was measured. IPC reduced infarct size in the nondiabetic rats but not in the diabetic animals. In diabetic rats, IPC induced phosphorylation of the mitogen-activated protein kinases and of heat shock protein 27. We conclude that protection by IPC is blocked by diabetes mellitus in the rat heart in vivo without affecting phosphorylation of mitogen-activated protein kinases or heat shock protein 27. Therefore, the blockade mechanism of diabetes mellitus is downstream of mitogen-activated kinases and heat shock protein 27.

Protection against cephalosporin-induced lipid peroxidation and nephrotoxicity by (+)-cyanidanol-3 and vitamin E

The ability of the clinically used cephalosporins: cephalothin, cefotaxime and cefotiam to induce lipid peroxidation (LPO) and renal damage was compared to that of nephrotoxic cephaloridine under in vivo conditions. Glutathione was measured in rat liver or in renal cortex as non-protein sulfhydryls. LPO was measured in plasma, renal cortex and liver by the generation of malondialdehyde or as the increase in renal cortical concentration of conjugated dienes. Impairment of renal function was measured as the decrease in renal cortical accumulation of the organic anion p-aminohippurate (PAH). Administration of cephalosporins to rats as a single dose (2000 mg/kg, ip) induced a significant glutathione-depletion in the renal cortex with cephaloridine, and in the liver with cephaloridine, cephalothin and cefotiam. Treatment of rats with cephaloridine, cephalothin and cefotiam (200, 500, or 1000 mg kg-1 day-1, ip) for 5 days resulted in a dose-dependent increase of LPO in the renal cortex. While cephaloridine induced the highest concentration of conjugated diene, cefotaxime had no effect. Measurements of PAH accumulation in renal cortical slices from cephalosporin-treated rats showed a dose-dependent decrease in the renal cortical accumulation of PAH. Pretreatment with the antioxidants vitamin E or cyanidanol (400 mg kg-1 day-1, ip) 1 h before treatment with cephaloridine, cephalothin or cefotiam (1000 mg kg-1 day-1, ip) for 3 days inhibited cephalosporin-induced LPO and significantly reduced the impairment of renal cortical accumulation of PAH. The potential of different cephalosporins for inducing LPO and reducing PAH accumulation was ranked as follows: cephaloridine > cephalothin > cefotiam > cefotaxime.

Superfluid-helium converter for accumulation and extraction of ultracold neutrons

We report the first successful extraction of accumulated ultracold neutrons (UCN) from a converter of superfluid helium, in which they were produced by downscattering neutrons of a cold beam from the Munich research reactor. Windowless UCN extraction is performed in vertical direction through a mechanical cold valve. This prototype of a versatile UCN source is comprised of a novel cryostat designed to keep the source portable and to allow for rapid cooldown. We measured time constants for UCN storage and extraction into a detector at room temperature, with the converter held at various temperatures between 0.7 and 1.3 K. The UCN production rate inferred from the count rate of extracted UCN is close to the theoretical expectation.

The Influence of Fluoroquinolone Drugs on the Bacterial Growth of S. epidermidis Utilizing the Unique Potential of Vibrational Spectroscopy

Increasing resistance of many antibiotics has made the design of new drugs necessary. To assist a target-oriented search for new structures and for the elucidation of the mode of action of existing drugs, powerful analytical techniques are required. In this work, vibrational spectroscopy is used to shed more light on the as-yet elusive interaction of gyrase inhibitors of the fluoroquinolone type with their biological target inside the Gram-positive bacterium Staphylococcus epidermidis by investigating whole-cell changes that occur as a result of the presence of the drug moxifloxacin. IR absorption and Raman spectra with excitation off resonance (lambda exc = 532 nm) and in resonance with the biological targets DNA and the aromatic amino acids of gyrase (lambda exc = 244 nm) were recorded for unperturbed bacteria and bacteria in varying drug concentrations (0.08, 0.16, 0.27, and 0.62 microg moxifloxacin/mL bacterial culture). The spectral changes caused by the action of the drug were analyzed with the help of statistical methods, such as hierarchical cluster analysis (HCA), principal component analysis (PCA), and Fisher's linear discriminant analysis (LDA) combined with variable selection. The wavenumbers mostly affected by the action of the drug could be assigned to protein and DNA moieties, supporting the proposed mechanisms of a tertiary complex of the fluoroquinolone, the enzyme gyrase, and DNA.

[Obsessive-compulsive disorders and religion in contemporary perspective]

After a retrospect on former viewpoints about the relationship between psychiatry and religion, especially concerning obsessive-compulsive disorders (S. Freud; "Ekklesiogenic Neurosis") a contemporary perspective shows: religion is hardly mentioned in German-speaking psychiatry textbooks. Pathogenic interaction between religion and psychological disorders is discussed in plurifactorial perspective. Religious views can be distorted by psychic disorders and adapted to the disorders. Starting from an anthropological definition of religion (C. Geertz), the paper presents three functions of religion and explains the relationship of Christian faith and obsessions/compulsions. Teaching programs for students and psychiatrists seem indicated for a better understanding of religion (and its absence) in the context of psychological disorders.