ABSTRACT
Thermal and photoinduced processes accompanying complexation of photochromic spiropyrans (SPP) with Zn ions in acetone solution were characterized by means of UV-vis and X-ray absorption spectroscopies in operando regime. SPP ligands are usually transparent at λ > 350 nm, but after mixing with Zn ions, they produce a stable colored (ε = 32 000-38 000 M-1 cm-1) complex with maximum absorption at 525 nm, which makes them a powerful tool for monitoring metal-ion concentration in solution. The complex revealed fluorescence and photochromic behavior under static irradiation with visible light with constant photoreaction quantum yield across its characteristic absorption band. Zn K-edge X-ray absorption spectra show prominent changes in Zn local atomic structure between free Zn ions and Zn complex. The pump-flow-probe scheme was adapted to measure operando changes in Zn coordination upon light irradiation. Within experimental time resolution, we have determined that 20 µs after light irradiation, Zn ion is released out of the complex. This is the first example of the direct spectroscopic probe of the Zn photorelease from the spiropyran complex.
ABSTRACT
Healthy miners demonstrated increased relative levels of lysophosphatidyl choline and especially phosphatidyl inositol subunits. Metabolism of the latter could result in membrane accumulation of inositol triphosphate leading to cytoplasmic calcium increase and to bronchial smooth muscles contraction. Oral 20% choline chloride solution lowers bronchospasm in dust bronchitis patients with decreased serum subunits of phosphatidyl inositol and increased serum levels of phosphatidyl choline.
Subject(s)
Bronchitis/etiology , Bronchoconstriction , Dust/adverse effects , Mining , Occupational Diseases/etiology , Chronic Disease , Constriction, Pathologic/etiology , Humans , Occupational Diseases/epidemiology , Russia/epidemiologyABSTRACT
The morphology peculiarities of thymus epithelial canals of 120 Wistar-line rats with thymosin have been observed. Thymosin-5 introduction during 3 days after birth in the dosage of 50 g proved to eliminate the epithelial canals of rat thymus in 3, 7 days of the postnatal period. In this period the epithelial canals have been found in thymus of all intact and control physiological solution injected rats. In 14, 30 days after birth the epithelial canals in experimental rats are found more often than in control ones. Thus, for the first time the evidence of thymosin-dependent characteristics of thymus epithelial canals has been obtained. The possible influence of epithelial canals on the regulation of T-forerunners entrance thymus has been discussed.
Subject(s)
Thymosin/physiology , Thymus Gland/anatomy & histology , Aging/drug effects , Aging/physiology , Animals , Animals, Newborn , Epithelium/anatomy & histology , Epithelium/drug effects , Epithelium/metabolism , Rats , Rats, Inbred Strains , Thymosin/analogs & derivatives , Thymosin/pharmacology , Thymus Gland/drug effects , Thymus Gland/metabolismABSTRACT
By means of 3H-thymidine, radioautographic investigation of lymphocytopoiesis has been performed in the cortex and medulla of the rat thymus for 2 weeks after birth. In the newborn animals the index of labelled nuclei (ILN) in the medulla is higher than in the cortex. By the 14th day after birth a progressive drop of lymphocytes including the isotope takes place in the medulla. The decrease of ILN in the medulla occurs against the background of increasing amount of epithelioreticulocytes with vacuoles and dystrophic changes in the nucleus and cytoplasm, that make groups of Hassal's bodies.
Subject(s)
Animals, Newborn/immunology , T-Lymphocytes/cytology , Thymus Gland/immunology , Animals , Animals, Newborn/anatomy & histology , Cell Differentiation , Rats , T-Lymphocytes/immunology , Thymus Gland/cytologyABSTRACT
Morphological reactions of the thymus to penetration of foreign antigens into the organism should be further investigated. In the work presented, morphometric, histological and histochemical methods have been applied to study specific thymic reactions of the rat fetuses to antenatal antigenic stimulation. The antigenic stimulation of the fetuses results in an increased thymic function. The changes observed in it resemble, in general, an accidental involution. A specific feature of the fetal thymic reaction is an essential enlargement of the medullary substance volume and appearance of the thymic bodies (Hassall's bodies) that demonstrates an accelerated maturation of the thymus.
