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101.
102.
Henryk Pospieszny Marta Budziszewska Beata Hasiów‐Jaroszewska Aleksandra Obrępalska‐Stęplowska Natasza Borodynko 《Journal of Phytopathology》2010,158(1):56-62
Three isolates of Tomato torrado virus (ToTV) were found in Poland. The isolates were characterized on the basis of their symptomatology on plant species, serological reactions, electron microscopy, and nucleotide and amino acid sequence analyses of coat protein subunit genes. In comparative tests, the Polish ToTV isolates were shown to be closely related to each other and also to the isolate from Spain. 相似文献
103.
104.
Here we report, for the first time, the results of detailed GC and GC/MS analyses of the essential oil of a rare taxon in Serbia, Hypericum elegans Stephan ex Willd . One hundred and sixty two constituents identified accounted for 98.6% of the oil. The major components of the oil were undecane (31.9%), α‐pinene (16.7%), nonane (6.1%), bicyclogermacrene (5.8%), 2‐methyloctane (3.7%), and germacrene D (3.6%). Non‐terpenoids as chemotaxonomic markers constituted the main fraction of H. elegans oil, whereby n‐alkanes were the most abundant contributors of this fraction. Based on these results and previously published ones, we performed an intrasectional multivariate statistical comparison of corresponding essential‐oil chemical compositions. Principal component analysis (PCA) and agglomerative hierarchical clustering (AHC) of the data on the volatile profiles of section Hypericum taxa revealed that H. elegans either represents an oil chemotype of its own (AHC) or could be considered related to H. perforatum (PCA). 相似文献
105.
Ageing can be defined as “a progressive, generalized impairment of function, resulting in an increased vulnerability to environmental challenge and a growing risk of disease and death”. Ageing is likely a multifactorial process caused by accumulated damage to a variety of cellular components. During the last 20 years, gerontological studies have revealed different molecular pathways involved in the ageing process and pointed out mitochondria as one of the key regulators of longevity. Increasing age in mammals correlates with increased levels of mitochondrial DNA (mtDNA) mutations and a deteriorating respiratory chain function. Experimental evidence in the mouse has linked increased levels of somatic mtDNA mutations to a variety of ageing phenotypes, such as osteoporosis, hair loss, graying of the hair, weight reduction and decreased fertility. A mosaic respiratory chain deficiency in a subset of cells in various tissues, such as heart, skeletal muscle, colonic crypts and neurons, is typically found in aged humans. It has been known for a long time that respiratory chain-deficient cells are more prone to undergo apoptosis and an increased cell loss is therefore likely of importance in the age-associated mitochondrial dysfunction. In this review, we would like to point out the link between the mitochondrial energy balance and ageing, as well as a possible connection between the mitochondrial metabolism and molecular pathways important for the lifespan extension. 相似文献
106.
Aleksandra Szczepankiewicz Anna Bręborowicz Paulina Sobkowiak Anna Popiel 《Clinical and molecular allergy : CMA》2010,8(1):1-6
Background
Histamine-metabolizing enzymes (N-methyltransferase and amiloride binding protein 1) are responsible for histamine degradation, a biogenic amine involved in allergic inflammation. Genetic variants of HNMT and ABP1 genes were found to be associated with altered enzyme activity. We hypothesized that alleles leading to decreased enzyme activity and, therefore, decreased inactivation of histamine may be responsible for altered susceptibility to asthma.Methods
The aim of this study was to analyze polymorphisms within the HNMT and ABP1 genes in the group of 149 asthmatic children and in the group of 156 healthy children. The genetic analysis involved four polymorphisms of the HNMT gene: rs2071048 (-1637T/C), rs11569723 (-411C/T), rs1801105 (Thr105Ile = 314C/T) and rs1050891 (1097A/T) and rs1049793 (His645Asp) polymorphism for ABP1 gene. Genotyping was performed with use of PCR-RFLP. Statistical analysis was performed using Statistica software; linkage disequilibrium analysis was done with use of Haploview software.Results
We found an association of TT genotype and T allele of Thr105Ile polymorphism of HNMT gene with asthma. For other polymorphisms for HNMT and ABP1 genes, we have not observed relationship with asthma although the statistical power for some SNPs might not have been sufficient to detect an association. In linkage disequilibrium analysis, moderate linkage was found between -1637C/T and -411C/T polymorphisms of HNMT gene. However, no significant differences in haplotype frequencies were found between the group of the patients and the control group.Conclusions
Our results indicate modifying influence of histamine N-methyltransferase functional polymorphism on the risk of asthma. The other HNMT polymorphisms and ABP1 functional polymorphism seem unlikely to affect the risk of asthma. 相似文献107.
Agnieszka Jazwa Paulina Kucharzewska Justyna Leja Anna Zagorska Aleksandra Sierpniowska Jacek Stepniewski Magdalena Kozakowska Hevidar Taha Takahiro Ochiya Rafal Derlacz Elisa Vahakangas Seppo Yla-Herttuala Alicja Jozkowicz Jozef Dulak 《Genetic vaccines and therapy》2010,8(1):1-16
Background
Impaired wound healing in diabetes is related to decreased production of growth factors. Hence, gene therapy is considered as promising treatment modality. So far, efforts concentrated on single gene therapy with particular emphasis on vascular endothelial growth factor-A (VEGF-A). However, as multiple proteins are involved in this process it is rational to test new approaches. Therefore, the aim of this study was to investigate whether single AAV vector-mediated simultaneous transfer of VEGF-A and fibroblast growth factor 4 (FGF4) coding sequences will improve the wound healing over the effect of VEGF-A in diabetic (db/db) mice.Methods
Leptin receptor-deficient db/db mice were randomized to receive intradermal injections of PBS or AAVs carrying β-galactosidase gene (AAV-LacZ), VEGF-A (AAV-VEGF-A), FGF-4 (AAV-FGF4-IRES-GFP) or both therapeutic genes (AAV-FGF4-IRES-VEGF-A). Wound healing kinetics was analyzed until day 21 when all animals were sacrificed for biochemical and histological examination.Results
Complete wound closure in animals treated with AAV-VEGF-A was achieved earlier (day 19) than in control mice or animals injected with AAV harboring FGF4 (both on day 21). However, the fastest healing was observed in mice injected with bicistronic AAV-FGF4-IRES-VEGF-A vector (day 17). This was paralleled by significantly increased granulation tissue formation, vascularity and dermal matrix deposition. Mechanistically, as shown in vitro, FGF4 stimulated matrix metalloproteinase-9 (MMP-9) and VEGF receptor-1 expression in mouse dermal fibroblasts and when delivered in combination with VEGF-A, enhanced their migration.Conclusion
Combined gene transfer of VEGF-A and FGF4 can improve reparative processes in the wounded skin of diabetic mice better than single agent treatment. 相似文献108.
109.
Swida A Czarna M Woyda-Płoszczyca A Kicinska A Sluse FE Jarmuszkiewicz W 《Journal of bioenergetics and biomembranes》2007,39(1):109-115
A profile of free fatty acid (FFA) specificity in Acanthamoeba castellanii mitochondrial uncoupling is described. The FFA uncoupling specificity was observed as different abilities to stimulate resting
respiration, to decrease resting membrane potential, and to decrease oxidative phosphorylation efficiency. Tested unsaturated
FFA (C18–20) were more effective as uncouplers and protonophores when compared to tested saturated FFA (C8–18), with palmitic
acid (C16:0) as the most active. As FFA efficiency in mitochondrial uncoupling is related to physiological changes of fatty
acid composition (and thereby FFA availability) during growth of amoeba cells, it could be a way to regulate the activity
of an uncoupling protein and thereby the efficiency of oxidative phosphorylation during a cell life of this unicellular organism.
Aleksandra Swida and Małgorzata Czarna contributed equally to this work. 相似文献
110.
Zalejska-Fiolka J Kasperczyk A Kasperczyk S Błaszczyk U Birkner E 《Biological trace element research》2007,120(1-3):195-204
Effect of garlic supplementation on blood antioxidant status, lipid peroxidation, and coronary plaque formation process was
investigated in oxidized oil-fed rabbits. Eighteen adult male mixed European rabbits were given a balanced diet (21 g% protein,
34 g% fat, 45 g% carbohydrate), which contained isocaloristic addition of nonoxidized or oxidized rapeseed oil in the presence
and absence of garlic. The experiment lasted 24 weeks. At the beginning and every 6 weeks, rabbits were weighed, and blood
was taken. To evaluate the antioxidant status of the rabbits, erythrocytes malondialdehyde (MDA) concentration, total superoxide
dismutase (t-SOD), and glutathione peroxidase (GPX) activations were determined. After the experiment was completed, aortas
were dissected for histological examinations. Changes in the contents of the above parameters and histological examinations
showed that oxidized rapeseed, oil administered to rabbits, caused the development of atherosclerotic changes and disturbed
antioxidant status. The addition of garlic in such diets inhibited atherosclerotic changes in the aorta wall, and it is related
to the homeostatic activity of antioxidative enzymes and lipid peroxidation. 相似文献