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131.
F. Suchentrunk H. Ben Slimen C. Stamatis H. Sert M. Scandura M. Apollonio Z. Mamuris 《Human Evolution》2006,21(2):151-165
Although only of medium size, and thus of little nutritional value compared to big game such as mammoths and ungulates, hares (Lepus spp.) probably have always been a food source for humans, as documented in archaeological finds. Nowadays, hares, particularly such species as the brown hare (L. europaeus), are among the most important game species in many European countries. For hunting, perhaps religious reasons, and in connection with certain myths, hares have been and are still being intentionally translocated. Ancient translocations by humans can be inferred from the presence of hares on islands that had no mainland connections, at least during the Pleistocene, the major evolutionary period of the genus Lepus. We review some of the literature on anthropogenic translocations of hares. We focus on three examples [the brown hare (L. europaeus), the Corsican hare (L. corsicanus), and the Sardinian hare (L. capensis)], where some molecular data could be used to trace the translocation routes and possible origins of introduced hare populations. Certain molecular marker systems, such as sequences of the hypervariable part I (HV-1) of the mitochondrial control region, show high variability in hare species and are thus promising for tracing both recent and ancient origins of translocated hares. Some other molecular marker systems as well as caveats connected with the use of such marker systems in the genus Lepus are also discussed. 相似文献
132.
Apostolos P. Apostolidis Demetrios Loukovitis Costas S. Tsigenopoulos 《Hydrobiologia》2008,600(1):169-176
In the present study, a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay was used to survey
variation in a 1450-bp mitochondrial DNA (mtDNA) segment which comprises part of the cytochrome oxidase III (COIII) and ATPase
subunit VI genes in 8 brown trout (Salmo trutta L) populations from the southern Balkans. In addition, a 300 bp fragment at the 5′ end of the control region was sequenced
from representatives of the populations studied providing the opportunity to assign PCR-RFLP haplotypes into major phylogenetic
lineages (i.e. Atlantic, Danubian, marmoratus, Adriatic and Mediterranean). The level of polymorphism found in the 1450 bp segment suggests that this PCR-RFLP assay may
be useful for future diagnostic analyses of mitochondrial DNA in brown trout populations. A reduced within-population genetic
variability but considerable among-population differentiation was observed. The results are in accordance with previous data
on phylogeography of Mediterranean brown trout suggesting that mitochondrial DNA haplotypes are distributed in a mosaic pattern
as a consequence of a complex evolutionary history. The present study shows that brown trout populations from the Southern
Balkans are highly divergent and possess a unique genetic profile that should be taken into account when establishing conservation
management programs.
Handling editor: C. Sturmbauer 相似文献
133.
George J. Tserevelakis Evgenia V. Megalou George Filippidis Barbara Petanidou Costas Fotakis Nektarios Tavernarakis 《PloS one》2014,9(1)
Elucidation of the molecular mechanisms regulating lipid storage and metabolism is essential for mitigating excess adiposity and obesity, which has been associated with increased prevalence of severe pathological conditions such as cardiovascular disorders and type II diabetes, worldwide. However, imaging fatty acid distribution and dynamics in vivo, at the cellular or organismal level is challenging. We developed a label-free method for visualizing lipid depositions in vivo, based on third harmonic generation (THG) microscopy. THG imaging requires a single pulsed-laser light source, alleviating the technical challenges of implementing coherent anti-Stokes Raman scattering spectroscopy (CARS) to detect fat stores in living cells. We demonstrate that THG can be used to efficiently and reliably visualize lipid droplets in Caenorhabditis elegans. Thus, THG microscopy offers a versatile alternative to fluorescence and dye-based approaches for lipid biology research. 相似文献
134.
135.
136.
Sereti Vasileia Lazaridou Athina Tananaki Chrysoula Biliaderis Costas G. 《Food biophysics》2021,16(3):365-380
Food Biophysics - Honey from cotton blossoms tends to crystallize rapidly resulting in a product with hard texture and low spreadability, even if it is processed via a controlled crystallization... 相似文献
137.
Twenty-five strains classified as Mycoplasma mycoides subsp. mycoides LC or subsp. capri have been compared by one-dimensional SDS-PAGE of their cellular proteins. A computerized numerical analysis revealed that the protein patterns of all but two aberrant strains formed one large phenon that separated clearly from representatives of the four other members of the 'M. mycoides cluster' at a similarity level (S) of 66% and which remained undivided at up to 78% S. At higher similarity levels, these strains fell heterogeneously into mixed sub-phenons containing strains of both subspecies. Serological comparisons by immunofluorescence largely confirmed the subspecies designations of the test strains, but also showed that some were serologically intermediate between subsp. mycoides and subsp. capri, being cross-reactive with both. These results confirm and enlarge upon those of our earlier studies indicating the protein-pattern inseparability of subsp. capri and subsp. mycoides LC strains and their distinctiveness from the classical M. mycoides subsp. mycoides SC strains and other members of the 'M. mycoides cluster'. As also recognized by other workers, subsp. mycoides LC and subsp. capri strains appear to comprise one large group, wherein those most readily identifiable as either type lie at either end of a serological spectrum that also contains serologically cross-reactive strains. Our observations therefore suggest the lines along which the three groups classified at present within the species M. mycoides (SC and LC strains of subsp. mycoides; subsp. capri) might eventually be reclassified, subject to direct genomic comparisons. 相似文献
138.
Costas D. Arvanitis Margaret S. Livingstone Natalia Vykhodtseva Nathan McDannold 《PloS one》2012,7(9)
The ability of ultrasonically-induced oscillations of circulating microbubbles to permeabilize vascular barriers such as the blood-brain barrier (BBB) holds great promise for noninvasive targeted drug delivery. A major issue has been a lack of control over the procedure to ensure both safe and effective treatment. Here, we evaluated the use of passively-recorded acoustic emissions as a means to achieve this control. An acoustic emissions monitoring system was constructed and integrated into a clinical transcranial MRI-guided focused ultrasound system. Recordings were analyzed using a spectroscopic method that isolates the acoustic emissions caused by the microbubbles during sonication. This analysis characterized and quantified harmonic oscillations that occur when the BBB is disrupted, and broadband emissions that occur when tissue damage occurs. After validating the system''s performance in pilot studies that explored a wide range of exposure levels, the measurements were used to control the ultrasound exposure level during transcranial sonications at 104 volumes over 22 weekly sessions in four macaques. We found that increasing the exposure level until a large harmonic emissions signal was observed was an effective means to ensure BBB disruption without broadband emissions. We had a success rate of 96% in inducing BBB disruption as measured by in contrast-enhanced MRI, and we detected broadband emissions in less than 0.2% of the applied bursts. The magnitude of the harmonic emissions signals was significantly (P<0.001) larger for sonications where BBB disruption was detected, and it correlated with BBB permeabilization as indicated by the magnitude of the MRI signal enhancement after MRI contrast administration (R2 = 0.78). Overall, the results indicate that harmonic emissions can be a used to control focused ultrasound-induced BBB disruption. These results are promising for clinical translation of this technology. 相似文献
139.
The percentages of formed cysts and growth rates were monthly estimated and analyzed rhythmometrically by cosinor for 5 clonal cultures of Scripsiella trochoidea Stein grown for 2 years under laboratory conditions, rended as constant as possible from the view point of environmental temperature (24 +/- 1 degree C), lighting (25 microEin m-2 s-1), and artificial seawater. A circannual rhythm is macroscopically apparent and microscopically (by cosinor) validated for 3 of 5 clones. The data of the other 2 clones did not allow rhythm detecting by the method used, suggesting differences in spectral structure of S. trochoidea strains both in terms of cyst formation and growth rate rhythms. 相似文献
140.
Rodríguez-Almazán C Torner FJ Costas M Pérez-Montfort R de Gómez-Puyou MT Puyou AG 《PloS one》2007,2(6):e497
The intracellular concentration of protein may be as high as 400 mg per ml; thus it seems inevitable that within the cell, numerous protein-protein contacts are constantly occurring. A basic biochemical principle states that the equilibrium of an association reaction can be shifted by ligand binding. This indicates that if within the cell many protein-protein interactions are indeed taking place, some fundamental characteristics of proteins would necessarily differ from those observed in traditional biochemical systems. Accordingly, we measured the effect of eight different proteins on the formation of homodimeric triosephosphate isomerase from Trypanosoma brucei (TbTIM) from guanidinium chloride unfolded monomers. The eight proteins at concentrations of micrograms per ml induced an important increase on active dimer formation. Studies on the mechanism of this phenomenon showed that the proteins stabilize the dimeric structure of TbTIM, and that this is the driving force that promotes the formation of active dimers. Similar data were obtained with TIM from three other species. The heat changes that occur when TbTIM is mixed with lysozyme were determined by isothermal titration calorimetry; the results provided direct evidence of the weak interaction between apparently unrelated proteins. The data, therefore, are strongly suggestive that the numerous protein-protein interactions that occur in the intracellular space are an additional control factor in the formation and stability of proteins. 相似文献