The involvement of calmodulin and protein kinases in the upstream of cytosolic and nucleic calcium signaling induced by hypoosmotic shock in tobacco cells.

Changes in Ca2+ concentrations in cytosol ([Ca2+]C) or nucleus ([Ca2+]N) may play some vital roles in plants under hypoosmotic shock (Hypo-OS). Here, we observed that Hypo-OS induces biphasic increases in [Ca2+]C and [Ca2+]N in two tobacco cell lines (BY-2) expressing apoaequorin either in the cytosol or in the nucleus. Both [Ca2+]C and [Ca2+]N were sensitively modulated by the inhibitors of calmodulin and protein kinases, supporting the view that calmodulin suppresses the 1st peaks and and protein kinases enhance 2nd peaks in [Ca2+]C and [Ca2+]N. Data also suggested that the 1st and 2nd events depend on the internal and extracellular Ca2+ sources, respectively.

7,8-Dihydropterin-6-carboxylic acid as light emitter of luminous millipede, Luminodesmus sequoiae.

A luminous millipede. Luminodesmus sequoiae, emits light centered at a wavelength of 500 nm. To determine the light emitter of this bioluminescent system, fluorescent compounds were isolated from pulverized cuticles. NMR and MS spectra of these compounds showed them to be pterin derivatives. Furthermore, proton/deuterium (H/D) exchange experiments by ESI-Q-TOF-MS and -MS/MS measurements have proved to be a powerful tool for elucidating these heteroaromatic compounds. Finally, we have concluded that 7,8-dihydropterin-6-carboxylic acid, a new natural product, is the light emitter of Luminodesmus bioluminescence.

High incorporation of L-amino acids to cereulide, an emetic toxin from Bacillus cereus.

Cereulide is a principal toxin causing emetic syndrome produced by Bacillus cereus. This paper deals with biosynthetic studies on this unusual cyclic depsipeptide toxin from 13C labeled L-amino acid precursors (Val, Leu, Ala) upon cultivation in synthetic media. The analyses were made at atomic level of the constituent amino- or oxy-acids through NMR and ESI-MS/MS spectroscopic methods on cereulide and its hydrolysate dipeptides. The incorporation of the 13C atom was 95% in each O-Val, O-Leu and L-Val, while 40% in D-Ala of cereulide.

Synthesis of 13C-dehydrocoelenterazine and model studies on Symplectoteuthis squid bioluminescence.

In the photoprotein of an Okinawan squid bioluminescence of Symplectoteuthis oualaniensis L a dehydrocoelenterazine has been assigned as a chromophoric precursor to its apoprotein. To prove this mechanism, we have established new synthetic route to ca. 100%-13C incorporated dehydrocoelenterazine and coelenterazine at the neighboring carbon of the 2-position of 2,3-dihydroimidazo-[1,2a]-pyrazinone skeleton. This 13C enriched dehydrocoelenterazine readily converted in equilibrium between its adduct forms as a diastereomixture with glutathione (GSH) or dithiothreitol (DTT) compounds having sulfhydryl group. Structures of such adducts were fixed under acidic conditions and then discussed by NMR spectroscopy as well as absorbance and fluorescence spectra.

Nutricao parenteral prolongada: experiencia e valorizacao do metodo. / Prolonged parenteral nutrition: experience and value of the method

Os autores expoem sua experiencia numa terapeutica de alta oferta calorico-proteica. Enfatizando as indicacoes da nutricao parenteral, tecem comentarios sobre o emprego do metodo e suas dificuldades, apresentando os resultados obtidos numa casuistica diversificada nos ultimos 70 meses

[Radioimmunologic determination of total IgE and allergen-specific IgE-antibodies in diffuse neurodermitis]. / Radioimmunologische Bestimmung des Gesamt-IgE und allergenspezifischer IgE-Antikörper bei Neurodermitis diffusa

Total IgE levels in sera of 165 patients with atopic dermatitis and 79 patients with dermatoses as well as normal control patients were determined by radioimmunoassay (Phadebas, Pharmacia). Although the mean value for patients with atopic dermatitis was found far above the mean value for normal controls, 38% of patients showed total IgE serum levels within the normal range. Highest IgE serum levels were observed in patients with the generalized form of the disease and in patients with asthma and allergic rhinitis. No direct correlation however, to severity of disease could be found. In a series of 50 patients prick tests were compared to total IgE serum levels and to levels of allergen specific antibodies determined by radioallergosorbent-test (RAST). Extracts of grass pollens and of animal dandruff were used. There was complete agreement between results of skin testing and RAST in at least 80%. While cross reactions were common with grass pollen extracts in RAST, there was no cross-over with animal dandruff. No correlation was found between titer of allergen specific antibody and severity of skin lesions. IgE specific antibody could be detected in 48% of patients with normal total IgE serum levels and in 82% of patients with elevated values.