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91.
92.
Ficová M Betáková T Pančík P Václav R Prokop P Halásová Z Kúdelová M 《Microbial ecology》2011,62(4):862-867
The MHV-68 (designed as Murid herpesvirus 4 (MuHV 4) strain 68) isolated from two rodents, Myodes glareolus and Apodemus flavicollis, is considered as a natural pathogen of free-living murid rodents. Recently, the detection of MHV antibodies in the blood
of animals living in the same biotope as MHV-infected mice has suggested that ticks may have a role in the transmission of
this pathogen. Ixodes ricinus is one the most abundant tick species in Europe known to transmit multiple pathogens causing human and animal diseases. In
this study, nymphs and larvae feeding on 116 individuals of a temperate lizard species—the green lizard Lacerta viridis captured in the Slovak Karst National Park, were examined for MHV-68. The specific sequence of virion glycoprotein 150 was
amplified in DNA individually isolated from I. ricinus ticks using single-copy sensitive nested polymerase chain reaction. MHV-68 was detected in ten of 649 nymphs and in five
of 150 larvae, respectively. We found that 9.6% of green lizards fed at least one MHV-68-infected immature tick. Occurrence
of MHV-68 within all ticks tested was 1.8%. This study is first to show that immature I. ricinus ticks feeding on free-living lizards in a Central European region could be infected with gammaherpesvirus (MHV-68), naturally
infecting free-living murid rodents. Our results provide evidence supporting the hypothesis that ticks may play a mediating
role in circulation of MHV-68 in nature. 相似文献
93.
Andrade CM Lopez PL Noronha BT Wink MR Borojevic R Margis R Lenz G Battastini AM Guma FC 《Cell and tissue research》2011,344(2):279-286
Ecto-5′-nucleotidase (eNT/CD73, E.C.3.1.3.5) is a glycosyl phosphatidylinositol (GPI)-linked cell-surface protein with several
functions, including the local generation of adenosine from AMP, with the consequent activation of adenosine receptors and
the salvaging of extracellular nucleotides. It also apparently functions independently of this activity, e.g., in the mediation
of cell-cell adhesion. Liver fibrosis can be considered as a dynamic and integrated cellular response to chronic liver injury
and the activation of hepatic stellate cells (HSCs) plays a role in the fibrogenic process. eNT/CD73 and adenosine are reported
to play an important role in hepatic fibrosis in murine models. Knockdown of eNT/CD73 leads to an increase in mRNA expression
of tissue non-specific alkaline phosphatase (TNALP), another AMP-degrading enzyme and thus no alteration is seen in the total
ecto-AMPase activity of the cell. eNT/CD73 knockdown also leads to changes in the expression of collagen I and a clear alteration
of cell migration. We suggest that eNT/CD73 protein expression controls cell migration and collagen expression in a mechanism
independent of changes in nucleotide metabolism. 相似文献
94.
María Soledad Romero Bastías 《Invertebrate reproduction & development.》2014,58(4):278-283
The spawning and larval development of Tegula euryomphala (Jones, 1844) were studied under laboratory conditions. The release of gametes was stimulated by raising temperature from 16 to 19?°C, and could be induced during several months of the year. Males always spawned first. Eggs were 155.6?μm in diameter and remained unattached to each other. Development was similar to that described for other Trochoidea and lasted 3–5?days at 19?°C. Larvae hatched approximately 24 h post-fertilization at the pre-torsional veliger stage. The larval protoconch of the metamorphic veliger measured 247?μm and was ornamented with six spiral threads and weakly ordered granulation. Larvae metamorphose without any natural substratum. 相似文献
95.
Poojah Jawallapersand Samson Sitheni Mashele Lidija Kova?i? Jure Stojan Radovan Komel Suresh Babu Pakala Nada Kra?evec Khajamohiddin Syed 《PloS one》2014,9(9)
Cytochrome P450 monooxygenases (CYPs/P450s) are heme-thiolate proteins whose role as a drug target against pathogenic microbes has been explored because of their stereo- and regio-specific oxidation activity. We aimed to assess the CYP53 family''s role as a common alternative drug target against animal (including human) and plant pathogenic fungi and its role in fungal-mediated wood degradation. Genome-wide analysis of fungal species revealed the presence of CYP53 members in ascomycetes and basidiomycetes. Basidiomycetes had a higher number of CYP53 members in their genomes than ascomycetes. Only two CYP53 subfamilies were found in ascomycetes and six subfamilies in basidiomycetes, suggesting that during the divergence of phyla ascomycetes lost CYP53 P450s. According to phylogenetic and gene-structure analysis, enrichment of CYP53 P450s in basidiomycetes occurred due to the extensive duplication of CYP53 P450s in their genomes. Numerous amino acids (103) were found to be conserved in the ascomycetes CYP53 P450s, against only seven in basidiomycetes CYP53 P450s. 3D-modelling and active-site cavity mapping data revealed that the ascomycetes CYP53 P450s have a highly conserved protein structure whereby 78% amino acids in the active-site cavity were found to be conserved. Because of this rigid nature of ascomycetes CYP53 P450s'' active site cavity, any inhibitor directed against this P450 family can serve as a common anti-fungal drug target, particularly toward pathogenic ascomycetes. The dynamic nature of basidiomycetes CYP53 P450s at a gene and protein level indicates that these P450s are destined to acquire novel functions. Functional analysis of CYP53 P450s strongly supported our hypothesis that the ascomycetes CYP53 P450s ability is limited for detoxification of toxic molecules, whereas basidiomycetes CYP53 P450s play an additional role, i.e. involvement in degradation of wood and its derived components. This study is the first report on genome-wide comparative structural (gene and protein structure-level) and evolutionary analysis of a fungal P450 family. 相似文献
96.
Carles Chiapella Rodrigo D. Radovan Jos Antonio Moreno Lorena Casares Jordi Barb Montserrat Llagostera 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》2000,470(2):950
To know the mechanisms involved in the activation of promutagenic aromatic amines mediated by plants, we used Persea americana S117 system (S117) for the activation of 2-aminofluorene (2-AF) and m-phenylenediamine (m-PDA) in Ames assays. In these assays, the effect of the diphenylene iodonium (DPI), an inhibitor of flavin-containing monooxygenases (FMOs), of the 1-aminobenzotriazole (1-ABT), an inhibitor of cytochromes P450 (cyt-P450s) and of the methimazole, a high-affinity substrate for FMOs, was studied. The efficacy of both inhibitors and of the methimazole was verified to find that they did partially inhibit the mutagenesis of both aromatic amines, activated with rat liver S9. Similarly, both inhibitors and methimazole did produce a significant decrease in 2-AF and m-PDA mutagenesis, when the activation system was S117, indicating that, similar to what occurs in mammalian systems, plant FMOs and cyt-P450s can metabolize aromatic amines to mutagenic product(s). However, the affinity of both FMOs and cyt-P450s of plant for 2-AF and m-PDA was different. Data obtained indicate that the activities of plant FMOs must be the main enzymatic system of m-PDA activation while, in 2-AF activation, plant cyt-P450s have the most relevant activities. In addition, peroxidases of the S117 system must contribute to 2-AF activation and some isoforms of FMOs and/or cyt-P450s of the S117 system, uninhibited by the inhibitors used, must be the responsible for a partial activation of m-PDA. 相似文献
97.
A disbalance between beta-adrenergic and muscarinic responses caused by hydrogen peroxide in rat airways in vitro 总被引:3,自引:0,他引:3
K Kramer C J Doelman H Timmerman A Bast 《Biochemical and biophysical research communications》1987,145(1):357-362
The effect of hydrogen peroxide on adrenergic and muscarinic responses of rat airway smooth muscle was studied. The trachea muscle and the lung parenchymal strip were contracted with methacholine and relaxed with (-)-isoprenaline. Recording of three (-)-isoprenaline curves on the trachea muscle and the lung parenchymal strip was followed by treatment for 30 min with hydrogen peroxide (H2O2) (1mM) after which a new dose response curve for (-)-isoprenaline was constructed. Using the trachea muscle this treatment with H2O2 resulted in a decrease of 61% of the maximum contraction by methacholine compared with the control and a complete inhibition of the relaxation by (-)-isoprenaline. In the lung parenchymal strip preparation we found, after the same treatment no reduction of the contraction by methacholine and 61% reduction of the relaxation by (-)-isoprenaline, compared with the control. The results demonstrate that the adrenergic response in rat airways is more susceptible to hydrogen peroxide than the muscarinic response. 相似文献
98.
Attachment theory is a very influential general concept of human social and emotional development, which emphasizes the role of early mother-infant interactions for infant's adaptive behavioural and stress copying strategies, personality organization and mental health. Individuals with disrupted development of secure attachment to mother/primary caregiver are at higher risk of developing mental disorders. This theory consists of the complex developmental psycho-neurobiological model of attachment and emerges from principles of psychoanalysis, evolutionary biology, cognitive-developmental psychology, ethology, physiology and control systems theory. The progress of modern neuroscience enables interpretation of neurobiological aspects of the theory as multi-level neural interactions and functional development of important neural structures, effects of neuromediattors, hormones and essential neurobiological processes including emotional, cognitive, social interactions and the special key role of mentalizing. It has multiple neurobiological, neuroendocrine, neurophysiological, ethological, genetic, developmental, psychological, psychotherapeutic and neuropsychiatric consequences and is a prototype of complex neuroscientific concept as interpretation of modern integrated neuroscience. 相似文献
99.
376 leptocephali ofAnguilla anguilla (L., 1758) from the Iberian Basin were analysed. The observed horizontal trends of abundance and particularly the mean sizes
contradict the expectations based on the hypothesis of larvae distribution exclusively by drift with Gulf and North Atlantic
Currents, and support the hypothesis of an active larval migration also south of the Azores. 相似文献
100.
The trapezoidal Candoninae from the Turiec Basin in Slovakia referred to the Candona sitari- and to C. aculeata-groups have characters that contrast with the valves of the Recent central European Candonines. The particularities concern the degree of calcification, the zone of concrescence, the overlap, and the presence of protuberances, the dorsum and the tubercles. Within the sitari-group, these characters evolve simultaneously with rapid evolution of the valve outline from subtrapezoidal to trapezoidal in shape. The species of this group acquire valve contours similar to those of the trapezoidal Candoninae of the Lake Pannon and the recent fauna of the long-lived lakes. The trapezoidal Candoninae of the Turiec Basin are associated with candonines that have triangular and rectangular carapaces with a pointed posteroventral margin. These three morphotypes indicate relatively stable habitats with weak environmental fluctuations. The trapezoidal species are rare in the littoral facies in both the north and the marginal areas of the Turiec Basin, but very abundant in the centre and south of the Basin. They probably lived in a profundal environment and their evolution probably occurred in relation to both sexual reproduction and a benthonic mode of life. The two groups comprise 18 species, of which 15 are described as new. 相似文献