Transport of Kinetin-814C in Petioles

Several differences in the translocation pattern of radioactive kinetin in plant petioles were determined. Radioactivity from kinetin-8-¹⁴C (Kn*) moved from donor agar blocks through petioles of bean and cocklebur but not of cotton. There was no difference in basipetal or acropetal movement of radioactivity from Kn* in cocklebnr petioles, but there was in bean petioles. In bean petioles this movement was preferentially basipetal, but it was influenced by the age of the petiole and by the presence of added indoleactic acid. The combination treatment accelerated the basipetal movement of radioactivity from Kn* in young bean petioles and not in old ones. All data is based on radioactivity translocated into receiver agar blocks which were assayed individually in a liquid scintillation spectrometer. The results show that plant species, direction of transport, age of tissue, and presence of IAA can all influence the translocation of Kn* in petioles.     

Structure of apolipoprotein A-I N terminus on nascent high density lipoproteins

Apolipoprotein A-I (apoA-I) is the major protein component of high density lipoproteins (HDL) and a critical element of cholesterol metabolism. To better elucidate the role of the apoA-I structure-function in cholesterol metabolism, the conformation of the apoA-I N terminus (residues 6-98) on nascent HDL was examined by electron paramagnetic resonance (EPR) spectroscopic analysis. A series of 93 apoA-I variants bearing single nitroxide spin label at positions 6-98 was reconstituted onto 9.6-nm HDL particles (rHDL). These particles were subjected to EPR spectral analysis, measuring regional flexibility and side chain solvent accessibility. Secondary structure was elucidated from side-chain mobility and molecular accessibility, wherein two major α-helical domains were localized to residues 6-34 and 50-98. We identified an unstructured segment (residues 35-39) and a β-strand (residues 40-49) between the two helices. Residues 14, 19, 34, 37, 41, and 58 were examined by EPR on 7.8, 8.4, and 9.6 nm rHDL to assess the effect of particle size on the N-terminal structure. Residues 14, 19, and 58 showed no significant rHDL size-dependent spectral or accessibility differences, whereas residues 34, 37, and 41 displayed moderate spectral changes along with substantial rHDL size-dependent differences in molecular accessibility. We have elucidated the secondary structure of the N-terminal domain of apoA-I on 9.6 nm rHDL (residues 6-98) and identified residues in this region that are affected by particle size. We conclude that the inter-helical segment (residues 35-49) plays a role in the adaptation of apoA-I to the particle size of HDL.     

A monoclonal antibody specific for non-reducing terminal Galα1-4Gal residues

A mouse monoclonal antibody (87.5) against Gal1-4Gal has been obtained after immunization with the disaccharide glycosidically coupled to a protein. The specificity was determined by studying its binding to a number of glycoconjugates and oligosaccharides.The antibody which was found to be highly specific for terminal Gal1-4Gal residues is a powerful tool for the detection of this structure in glycoproteins and glycolipids by immunochemicalin vitro methods. It is also useful forin vitro quantification of the free disaccharide.A thin layer chromatographic overlay assay using glycolipids and an immunoperoxidase technique is also described. The antibody 87.5 is used in this assay to identify human uroepithelium glycolipids with terminal Gal1-4Gal residues.Abbreviations Lactosylceramide Gal1-4GlcCer - globotriaosylceramide GbOse₃-ceramide, Gal1-4Gal1-4GlcCer - globotetraosylceramide globoside, GbOse₄-ceramide, GalNAc1-3Gal1-4Gal1-4GlcCer     

Spring Time and Fall Time Effects of 1,25-Dihydroxyvitamin D3, Cobalt (II) and (CoCl2(1,25(OH)2D3)4) Complex on Renal and Cerebral Enzymatic Markers in Rats

In this work, we studied the chronesthesia of 1,25-dihydroxyvitamin D 3 (1,25(OH) 2 D 3 ), cobalt (II) chloride and of the complex [CoCl 2 (1,25(OH) 2 D 3 ) 4 ]. The study was carried out in spring and autumn on AP and ?-GT activities in brain and kidney of rats during the rodents' active period. In rat brain, in both seasons, 1,25(OH) 2 D 3 enhanced AP activity by 59 % in spring and 21 % in autumn and ?-GT by 39 and 35 % respectively. Cobalt (II) stimulated AP activity by 34 and 29 % respectively. The complex was mainly active on ?-GT activity (70 and 36 %) showing a synergic effect on ?-GT activity in June. In rat kidney, during spring, the induction of AP activity for 1,25(OH) 2 D 3 , cobalt (II) chloride and their complex was, respectively 21, 18 and 12 %. The ?-GT activity was not modified during this period, whereas in autumn, it was inhibited by -33, -50 and -28 %. The AP activity in autumn was not altered. We conclude that the effects on the two enzymatic markers of the three compounds 1,25(OH) 2 D 3 , cobalt (II) chloride and [CoCl 2 (1,25(OH) 2 D 3 ) 4 ] are quite different in Spring and Autumn, and this is explained on the basis of chronesthesia.     

Biochemical and antiviral activities of enzymatic hydrolysates from different invasive French seaweeds

Proliferations of green, brown and red algae appear in shallow sandy bays in North Brittany (France), and they represent a real economic constraint for the affected communities. In addition to the nuisance for residents and tourist activity, the communities must carry out systematic collection. The collected algae are spread on agricultural land spreading or composted, but these solutions reach their limits rapidly, bringing little added value to the collected algae. Seaweeds are potentially excellent sources of bioactive metabolites that could represent useful leads in the development of new functional ingredients in pharmaceutical and cosmetic industries. The aim of this study was to propose the use of an enzyme-assisted extraction as a tool to improve the extraction efficiency of antiviral compounds from three invasive French seaweeds. We selected the red Solieria chordalis, the green Ulva sp. and the brown Sargassum muticum as models for these experiments. In comparison with water extraction at 50 °C for the same time of treatment, enzymatic hydrolysis increased the yields. The data suggest the potential of enzymatic hydrolysis for producing active fractions in the function of the algal biomass, the behaviour of the cell wall, the selectivity and the action of the enzyme. Enzymatic hydrolysis appeared less effective for polyphenol recovery, but was a promising softer technique for recovering proteins, neutral sugars, uronic acids and sulphate groups. The solvent-free process, higher extraction rate and higher yields, coupled to time-saving and lower cost, make this method economical and sustainable. By using a cell viability assay, all hydrolysate fractions tested were shown to be non-toxic to Vero cells. After 3 days of treatment, no microscopically visible alteration of normal cell morphology was observed even at 500 μg mL^?1. S. chordalis extracts have an effective antiviral activity with EC₅₀ between 23.0 and 101.1 μg mL^?1 at a multiplicity of infection of 0.001 ID₅₀/cells; 100 % and 98 % cellular protection were obtained for 500 μg mL^?1 of hydrolysate extracts carbohydrase C3 and blank, respectively. Other extracts from S. chordalis inhibited viral production less effectively.     

Cardiac troponin I levels in canine pyometra

Background  

Myocardial injury may contribute to unexpected deaths due to pyometra. To detect myocardial damage, measurement of cardiac troponin I (cTnI) is currently the most sensitive and specific method. The aims of the present study were to evaluate presence of myocardial damage in canine pyometra by analysis of cTnI, to explore whether myocardial injury was associated with systemic inflammatory response syndrome (SIRS) and to evaluate whether other clinical or laboratory parameters were associated with cTnI increase.     

The fibrillogenic L178H variant of apolipoprotein A-I forms helical fibrils

A number of amyloidogenic variants of apoA-I have been discovered but most have not been analyzed. Previously, we showed that the G26R mutation of apoA-I leads to increased β-strand structure, increased N-terminal protease susceptibility, and increased fibril formation after several days of incubation. In vivo, this and other variants mutated in the N-terminal domain (residues 26 to ～90) lead to renal and hepatic accumulation. In contrast, several mutations identified within residues 170 to 178 lead to cardiac, laryngeal, and cutaneous protein deposition. Here, we describe the structural changes in the fibrillogenic variant L178H. Like G26R, the initial structure of the protein exhibits altered tertiary conformation relative to wild-type protein along with decreased stability and an altered lipid binding profile. However, in contrast to G26R, L178H undergoes an increase in helical structure upon incubation at 37°C with a half time (t(1/2)) of about 12 days. Upon prolonged incubation, the L178H mutant forms fibrils of a diameter of 10 nm that ranges in length from 30 to 120 nm. These results show that apoA-I, known for its dynamic properties, has the ability to form multiple fibrillar conformations, which may play a role in the tissue-specific deposition of the individual variants.     

Genomic structure, polymorphism and expression of ACCN1 and ACCN3 genes in the horse

A category of cation gate proteins was shown to be present in sensory neurons and act as receptors of protons present in tissues such as muscles. The Amiloride-sensitive Cation Channel, Neuronal (ACCN) gene family is known to play a role in the transmission of pain through specialized pH sensitive neurons. Muscles from horses submitted to strenuous exercises produce lactic acid, which may induce variable pain through ACCN differential properties. The sequences of the equine cDNAs were determined to be 2.6 kb in length with an open reading frame of 1539 bp for ACCN1 and 2.1 kb in length with an open reading frame of 1602 bp for ACCN3. The ACCN1 gene is 990 kb long and contains 10 exons, and the ACCN3 gene is 4.2 kb long and contains 11 exons. The equine ACCN1 and ACCN3 genes have an ubiquitous expression but ACCN1 is more highly expressed in the spinal cord. We identified one alternative ACCN3 splicing variant present in various equine tissues. These mRNA variants may encode two different protein isoforms 533 and 509 amino acids long. Ten single nucleotide polymorphisms (SNPs) were detected for ACCN1; five in the coding and five in the non-coding region, with no amino acid change, while the three SNPs identified in the coding region of the ACCN3 gene introduce amino acid changes. The equine in silico promoter sequence reveals a structure similar to those of other mammalian species, especially for the ACCN1 gene.