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1.
Systemic effects of chronically administered methyl prednisolonate and methyl 17-deoxyprednisolonate
The systemic activities of methyl prednisolonate and methyl 17-deoxyprednisolonate (1) were studied in rats. Methyl 17-deoxyprednisolonate produced significant changes in the amount of sodium ion (decreased) and potassium ion (increased) in urine; however, methyl prednisolonate had no effect on electrolyte balance. Both methyl prednisolonate and methyl 17-deoxyprednisolonate had no effect on liver glycogen content, plasma corticosterone level and relative adrenal weight. In contrast, the parent compound prednisolone caused a significant decrease in liver glycogen content, plasma corticosterone level and relative adrenal weight. 相似文献
2.
Two multi-dimensional heteronuclear NMR experiments are described for assigning the resonances in uniformly 15N- and 13C-labeled proteins. In one experiment (HCNH-TOCSY), the amide nitrogen and proton are correlated to the side-chain protons and carbons of the same and preceding residue. In a second triple resonance experiment (HC(CO)NH-TOCSY), the amide nitrogen and proton of one residue is correlated exclusively with the side-chain proton and carbon resonances of the preceding residue by transferring magnetization through the intervening carbonyl. The utility of these two experiments for making sequential resonance assignments in proteins is illustrated for [U-15N,13C]FKBP (107 residues) complexed to the immunosuppressant, ascomycin. 相似文献
3.
3JH alpha,H beta and 3JN,H beta coupling constants were measured for isotopically labeled FKBP when bound to the immunosuppressant, ascomycin, using a 1H-coupled 3D HCCH-TOCSY and 15N-coupled 3D HSQC-TOCSY experiment, respectively. From an analysis of these two sets of coupling constants, stereospecific beta-proton assignments and chi 1 rotamers for FKBP have been obtained. All of the chi 1 rotamers were consistent with the chi 1 angles measured in the X-ray crystal structure of the FKBP/FK506 complex, suggesting that the structures of the two complexes are similar. 相似文献
4.
The midgut epithelial cells of many invertebrates may possess microorganisms which act as symbionts or pathogens (bacteria, microsporidia, viruses). During our previous studies on Isohypsibius granulifer granulifer Thulin, 1928 (Tardigrada, Eutardigrada), which examined alterations of the midgut epithelium during oogenesis, we found that some of the specimens were infected with microsporidia. All stages of pathogens occurred in the cytoplasm of the digestive cells in the midgut epithelium of I. g. granulifer that were infected with microsporidia: meronts, sporonts, sporoblasts, and spores. The cytoplasm of the digestive cells was rich in mitochondria, cisterns of rough endoplasmic reticulum (RER), and Golgi complexes. Autophagy in the digestive cells of the dorsal midgut was much more intensive in comparison with noninfected specimens. Membranes of phagophores surrounded the pathogens forming autophagosomes. These latter structures fused with lysosomes forming autolysosomes and residual bodies appeared. Neither glycogen granules nor droplets of varying electron density, which accumulated in digestive cells during vitellogenesis and choriogenesis, appeared in individuals with microsporidia. While the midgut epithelium in noninfected specimens takes part in vitellogenesis and choriogenesis, in infected specimens, midgut cells are involved in the process of autophagy as a survival strategy. 相似文献
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Agnieszka Saamaszyska‐Guz Izabela Serafiska Pawe Bcal Stephen Douthwaite 《Cellular microbiology》2020,22(7)
Campylobacter jejuni is a bacterial pathogen that is generally acquired as a zoonotic infection from poultry and animals. Adhesion of C. jejuni to human colorectal epithelial cells is weakened after loss of its cj0588 gene. The Cj0588 protein belongs to the type I group of TlyA (TlyAI) enzymes, which 2′‐O‐methylate nucleotide C1920 in 23S rRNA. Slightly longer TlyAII versions of the methyltransferase are found in actinobacterial species including Mycobacterium tuberculosis, and methylate not only C1920 but also nucleotide C1409 in 16S rRNA. Loss of TlyA function attenuates virulence of both M. tuberculosis and C. jejuni. We show here that the traits impaired in C. jejuni null strains can be rescued by complementation not only with the original cj0588 (tlyA I) but also with a mycobacterial tlyA II gene. There are, however, significant differences in the recombinant phenotypes. While cj0588 restores motility, biofilm formation, adhesion to and invasion of human epithelial cells and stimulation of IL‐8 production in a C. jejuni null strain, several of these properties are further enhanced by the mycobacterial tlyA II gene, in some cases to twice the original wild‐type level. These findings strongly suggest that subtle changes in rRNA modification patterns can affect protein synthesis in a manner that has serious consequences for bacterial pathogenicity. 相似文献
8.
Abstract Various phophorodithioates derived from thionucleosides were synthesis by the reaction anhydronucleosides with phosphorodithioic acids 相似文献
9.
Artur Kaminski Grzegorz Gut Izabela Uhrynowska-Tyszkiewicz Ewa Olender 《Cell and tissue banking》2013,14(1):141-145
Personnel directly involved in the donation, procurement, testing, processing, preservation, storage and distribution of human tissues and cells should be appropriately qualified and provided with timely and relevant training according to EU directives. In the time of new tissue and cells regulations implementation such a training system existed in Poland only at a local level. The first training programme outlines for various groups of health professionals engaged in tissue banking practice was created in co-operation with the Institute for LifeLong Learning at University of Barcelona in 2006. This initial training courses were financially supported by EU Transition Facility Programme 2004. Then, starting from 2006, based on previous experience, system of advanced training courses was created. This training programme was financially supported by the National Programme for the Development of Transplantation Medicine 2006–2009—POLGRAFT financed by Polish Ministry of Health. During 2006 and 2007 first set of tissue banking initial training courses were provided according to TF 2004 project. Over 200 pathologists, forensic medicine specialists and other medical doctors responsible for donor screening and classification, medical directors of tissue establishments, technical staff; tissue graft users: orthopaedic surgeons, neurosurgeons, cardiosurgeons and ophthalmologists were trained. Between 2006 and 2009 there were organized 8 advanced tissue banking training courses according to POLGRAFT programme. There were organized both theoretical and practical courses on various aspects of tissue for over 350 persons. We present our experience in organisation of international and national tissue banking training courses. 相似文献
10.
Tumor differentiation factor (TDF) is a protein produced by the pituitary and secreted into the blood stream. The mechanism of its action has still not been elucidated, although the associated protein receptor was identified. Furthermore, the TDF protein does not have any homology with other known proteins, and the crystal structure of TDF also is not available at this time. To gain some insight into the structure of this rather underexplored protein, we have performed a molecular dynamics simulation of a model TDF structure. The structural stability of this protein is evaluated as a function of time. The time dependent structural changes of four cysteine residues present in this structure also are explored. 相似文献