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91.
Livia G. R. P. Macêdo Milena Carvalho-Silva Gabriela K. Ferreira Júlia S. Vieira Natália Olegário Renata C. Gonçalves Francieli S. Vuolo Gustavo C. Ferreira Patrícia F. Schuck Felipe Dal-Pizzol Emilio L. Streck 《Neurochemical research》2013,38(12):2625-2630
Tyrosinemia type II, also known as Richner–Hanhart syndrome, is an autosomal recessive inborn error of metabolism caused by a deficiency of hepatic cytosolic tyrosine aminotransferase, and is associated with neurologic and development difficulties in numerous patients. Considering that the mechanisms underlying the neurological dysfunction in hypertyrosinemic patients are poorly known and that studies demonstrated that high concentrations of tyrosine provoke oxidative stress in vitro and in vivo in the cerebral cortex of rats, in the present study we investigate the oxidative stress parameters (enzymatic antioxidant defenses, thiobarbituric acid-reactive substances and protein carbonyl content) in cerebellum, hippocampus and striatum of 30-old-day rats after acute administration of l-tyrosine. Our results demonstrated that the acute administration of l-tyrosine increased the thiobarbituric acid reactive species levels in hippocampus and the carbonyl levels in cerebellum, hippocampus and striatum. In addition, acute administration of l-tyrosine significantly decreased superoxide dismutase activity in cerebellum, hippocampus and striatum, while catalase was increased in striatum. In conclusion, the oxidative stress may contribute, along with other mechanisms, to the neurological dysfunction characteristic of hypertyrosinemia and the administration of antioxidants may be considered as a potential adjuvant therapy for tyrosinemia, especially type II. 相似文献
92.
93.
Djermanovic Mirjana Baralic Ivana Pejic Snezana 《Biological trace element research》2020,194(2):545-551
Biological Trace Element Research - The mercury concentration was quantified in frozen and canned fish found in the market of the Republic of Srpska, Bosnia and Herzegovina. Using the method of... 相似文献
94.
Andersen JR Zein I Wenzel G Krützfeldt B Eder J Ouzunova M Lübberstedt T 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,114(2):307-319
Forage quality of maize is influenced by both the content and structure of lignin in the cell wall. Phenylalanine Ammonia-Lyase (PAL) catalyzes the first step in lignin biosynthesis in plants; the deamination of L-phenylalanine to cinnamic acid. Successive enzymatic steps lead to the formation of three monolignols, constituting the complex structure of lignin. We have cloned and sequenced a PAL genomic sequence from 32 maize inbred lines currently employed in forage maize breeding programs in Europe. Low nucleotide diversity and excessive linkage disequilibrium (LD) was identified at this PAL locus, possibly reflecting selective constrains resulting from PAL being the first enzyme in the monolignol, and other, pathways. While the association analysis was affected by extended LD and population structure, several individual polymorphisms were associated with neutral detergent fiber (not considering population structure) and a single polymorphism was associated with in vitro digestibility of organic matter (considering population structure). 相似文献
95.
96.
Gorodkin J Cirera S Hedegaard J Gilchrist MJ Panitz F Jørgensen C Scheibye-Knudsen K Arvin T Lumholdt S Sawera M Green T Nielsen BJ Havgaard JH Rosenkilde C Wang J Li H Li R Liu B Hu S Dong W Li W Yu J Wang J Staefeldt HH Wernersson R Madsen LB Thomsen B Hornshøj H Bujie Z Wang X Wang X Bolund L Brunak S Yang H Bendixen C Fredholm M 《Genome biology》2007,8(4):R45-16
97.
Milena R. Martelli Fran?ois Brygo Philippe Delaporte Xavier Rouau C??cile Barron 《Food biophysics》2011,6(4):433-439
During the wheat milling process, the bran fractionation is related to its mechanical properties, which are measured using
tensile tests on hand-isolated tissues. However, the dissection of wheat tissues implies a soaking stage in water that can
modify tissue properties. New methodologies are required to evaluate wheat tissue properties directly on native grains. The
aim of this work was to estimate wheat grain tissue cohesion by the ionization effectiveness via laser-induced breakdown spectroscopy
(LIBS) technique. Isolated bran tissues and wheat grains were submitted to LIBS analysis using a pulsed argon fluoride (193 nm,
15 ns, 1 Hz, 2 J cm−2) excimer laser and a compact optic fiber spectrometer (HR2000). The first approach was to correlate the ratios of ionic to
atomic emission lines (MgII/MgI and CaII/CaI) of isolated tissues to their mechanical measurements. The energy needed to rupture
the tissue was correlated to MgII/MgI (R
2 = 0.72). Secondly, native grains were irradiated and chemometrics was applied to discriminate tissue spectra. The aleurone
layer isolated after the soaking step presented a higher MgII/MgI than the aleurone layer from native grains, indicating a
possible water effect on the tissue cohesion. In conclusion, the LIBS technique may be a potential method for rapid structural
analysis of vegetal material allowing wheat population screening of both compositional and mechanical properties. 相似文献
98.
Amir Malaki Nik Marcela Alexander Vaino Poysa Lorna Woodrow Milena Corredig 《Food biophysics》2011,6(1):26-36
The effect of soy protein subunit composition on the acid-induced aggregation of soymilk was investigated by preparing soymilk
from different soybean lines lacking specific glycinin and β-conglycinin subunits. Acid gelation was induced by glucono-δ-lactone
(GDL) and analysis was done using diffusing wave spectroscopy and rheology. Aggregation occurred near pH 5.8 and the increase
in radius corresponded to an increase in the elastic modulus measured by small deformation rheology. Diffusing wave spectroscopy
was also employed to follow acid gelation, and data indicated that particle interactions start to occur at a higher pH than
the pH of onset of gelation (corresponding to the start of the rapid increase in elastic modulus). The protein subunit composition
significantly affected the development of structure during acidification. The onset of aggregation occurred at a higher pH
for soymilk samples containing group IIb (the acidic subunit A3) of glycinin, than for samples prepared from Harovinton (a commercial variety containing all subunits) or from genotypes
null in glycinin. The gels made from lines containing group I (A1, A2) and group IIb (A3) of glycinin resulted in stiffer acid gels compared to the lines containing only β-conglycinin. These results confirmed that
the ratio of glycinin/β-conglycinin has a significant effect on gel structure, with an increase in glycinin causing an increase
in gel stiffness. The type of glycinin subunits also affected the aggregation behavior of soymilk. 相似文献
99.
100.
Chakravorty A Awad MM Hiscox TJ Cheung JK Carter GP Choo JM Lyras D Rood JI 《PloS one》2011,6(7):e22762
Clostridium perfringens is the causative agent of clostridial myonecrosis or gas gangrene and produces many different extracellular toxins and enzymes, including the cysteine protease α-clostripain. Mutation of the α-clostripain structural gene, ccp, alters the turnover of secreted extracellular proteins in C. perfringens, but the role of α-clostripain in disease pathogenesis is not known. We insertionally inactivated the ccp gene C. perfringens strain 13 using TargeTron technology, constructing a strain that was no longer proteolytic on skim milk agar. Quantitative protease assays confirmed the absence of extracellular protease activity, which was restored by complementation with the wild-type ccp gene. The role of α-clostripain in virulence was assessed by analysing the isogenic wild-type, mutant and complemented strains in a mouse myonecrosis model. The results showed that although α-clostripain was the major extracellular protease, mutation of the ccp gene did not alter either the progression or the development of disease. These results do not rule out the possibility that this extracellular enzyme may still have a role in the early stages of the disease process. 相似文献