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91.
Ralf Hand Georgios N. Hadjikyriakou Charalambos S. Christodoulou Boo Frajman 《Botanical journal of the Linnean Society. Linnean Society of London》2015,179(2):295-307
The leafy spurges, Euphorbia subgenus Esula, have one of their diversity centres in the Mediterranean, which is considered to be one of the 25 biodiversity hot‐spots. The eastern Mediterranean, in particular, is characterized by its high species richness and is therefore considered to be a cradle for lineage diversification. However, the area remains neglected in phylogenetic studies. Using nuclear ribosomal internal transcribed spacer (ITS) and plastid trnT‐trnF sequences, we explored the phylogenetic relationships in the predominantly eastern Mediterranean E. hierosolymitana group, which is characterized by a woody habit. The widespread shrublets E. acanthothamnos, E. glabriflora and E. spinosa, which are similar in habit, are not most closely related, the last two forming a sister clade to other taxa. From the E. acanthothamnos alliance, dendroid shrubs evolved at least two, but possibly four, times, giving rise to widespread E. bivonae and E. hierosolymitana, the Cretan endemic E. sultan‐hassei and the here newly described and genetically most divergent E . lemesiana , endemic to Cyprus. We provide a taxonomic treatment and morphological comparison with the similar, but not most closely related, E. hierosolymitana. Our study underlines the phytogeographical peculiarity of Cyprus and contributes to our current knowledge on the diversification patterns in the eastern Mediterranean. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 295–307. 相似文献
92.
Arvanitis Nikolaos Kotzamanidis Charalambos Z. Skaracis George N. Karagouni Amalia D. 《World journal of microbiology & biotechnology》2004,20(3):291-296
The antimicrobial activities of five commercial disinfectants containing quaternary ammonium compound-isopropanol (D1), sodium
methyl dithiocarbamate (D2), sodium thiocarbamate (D3), sodium dimethyl dithiocarbamate (D4) and formaldehyde (D5) were studied
against three main saccharolytic indigenous isolates (Bacillus cereus, Lactobacillus plantarum and Leuconostoc mesenteroides) from a beet sugar extraction line. Preliminary studies suggested that although all the disinfectants were effective against
those isolates, the high economic cost in combination with large amounts of the disinfectants D2, D3 and D4 weaken their possibility
for industrial use. Therefore, the minimum inhibitory concentration (MIC) of the other two examined disinfectants D1 and D5
was determined and survivor curves were obtained, for a period of 7 days. Bacterial counts against time (h) suggested that
D1 was more effective than D5 against the microbial population. In particular, D1 was bacteriolytic above 7 mg/l for B. cereus and bactericidal above 80 mg/l for Lc. mesenteroides and above 100 mg/l for L. plantarum. The disinfectant D5 was bacteriolytic above 25 mg/l for B. cereus and bactericidal above 500 mg/l for Lc. mesenteroides and L. plantarum. Taking into consideration both features, i.e. high concentration and very low cost, the use of D5 (formaldehyde) appeared
more suitable to the concerned beet sugar processor.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
93.
SURF-6 is a bona fide nucleolar protein comprising an evolutionary conserved family that extends from human to yeast. The
expression of the mammalian SURF-6 has been recently found to be regulated during the cell cycle. In order to determine the
importance of SURF-6 in mammalian cells, we applied the Tet-On system to regulate conditionally, in response to tetracycline,
the expression of an antisense RNA (asRNA) that targets Surf-6 mRNA in mouse NIH/3T3 cells. Induced Surf-6 asRNA caused an effective depletion of SURF-6 protein resulted in cell death and in an apparent arrest in the G1 phase of
the cell cycle. These results provide for the first time evidence that expression of SURF-6 is essential for mammalian cell
viability, and suggest that SURF-6 might participate in the progression of cell cycle. 相似文献
94.
Background
Several molecular and cellular processes in the vertebrate brain exhibit differences between males and females, leading to sexual dimorphism in the formation of neural circuits and brain organization. While studies on large-scale brain networks provide ample evidence for both structural and functional sex differences, smaller-scale local networks have remained largely unexplored. In the current study, we investigate sexual dimorphism in cortical dynamics by means of spontaneous Up/Down states, a type of network activity that is exhibited during slow-wave sleep, quiet wakefulness, and anesthesia and is thought to represent the default activity of the cortex.Methods
Up state activity was monitored by local field potential recordings in coronal brain slices of male and female mice across three ages with distinct secretion profiles of sex hormones: (i) pre-puberty (17–21 days old), (ii) 3–9 adult (months old), and (iii) old (19–24 months old).Results
Female mice of all ages exhibited longer and more frequent Up states compared to aged-matched male mice. Power spectrum analysis revealed sex differences in the relative power of Up state events, with female mice showing reduced power in the delta range (1–4 Hz) and increased power in the theta range (4–8 Hz) compared to male mice. No sex differences were found in the characteristics of Up state peak voltage and latency.Conclusions
The present study revealed for the first time sex differences in intracortical network activity, using an ex vivo paradigm of spontaneously occurring Up/Down states. We report significant sex differences in Up state properties that are already present in pre-puberty animals and are maintained through adulthood and old age.95.
96.
Sofia M Billinis C Psychas V Birtsas P Sofianidis G Leontides L Knowles N Spyrou V 《Journal of wildlife diseases》2008,44(4):864-870
In 2002, postweaning multisystemic wasting syndrome (PMWS) was diagnosed in a European female wild boar (Sus scrofa), based on the detection of porcine circovirus 2 (PCV2) DNA in various organs, including the uterus, and on histopathologic lesions. This is the first detection of PCV2 DNA in the uterus of a wild boar. Three years later (2005), a wild boar < 6-8 mo of age was found moribund. It presented wasting and dyspnea and finally died. PCV2 DNA was detected in tissue samples, and histopathologic lesions consistent with PMWS were observed. Both wild boars were from neighboring hunting areas in central Greece. Two PCV2 strains from the wild boars were genetically characterized and compared to other reported PCV2 sequences from wild boars and domestic pigs. The PCV-2 sequences from the wild boars in this study were closely related to each other and were grouped with two isolates from wild boars from Hungary. The phylogenetic analysis revealed that the virus might be transmitted between hunting areas. In addition, PCV2 may spread from domestic pigs to wild boars and vice versa. 相似文献
97.
Katerina A. Moutou Evagelia A. Koutsogiannouli Costas Stamatis Charalambos Billinis Claudia Kalbe Massimo Scandura Zissis Mamuris 《Immunogenetics》2013,65(3):195-209
The Major Histocompatibility Complex (MHC) is a multigene family of outstanding polymorphism. MHC molecules bind antigenic peptides in the peptide-binding region (PBR) that consists of five binding pockets (P). In this study, we compared the genetic diversity of domestic pigs to that of the modern representatives of their wild ancestors, the wild boar, in two MHC loci, the oligomorphic DQA and the polymorphic DRB1. MHC nucleotide polymorphism was compared with the actual functional polymorphism in the PBR and the binding pockets P1, P4, P6, P7, and P9. The analysis of approximately 200 wild boars collected throughout Europe and 120 domestic pigs from four breeds (three pureblood, Pietrain, Leicoma, and Landrace, and one mixed Danbred) revealed that wild boars and domestic pigs share the same levels of nucleotide and amino acid polymorphism, allelic richness, and heterozygosity. Domestication did not appear to act as a bottleneck that would narrow MHC diversity. Although the pattern of polymorphism was uniform between the two loci, the magnitude of polymorphism was different. For both loci, most of the polymorphism was located in the PBR region and the presence of positive selection was supported by a statistically significant excess of nonsynonymous substitutions over synonymous substitutions in the PBR. P4 and P6 were the most polymorphic binding pockets. Functional polymorphism, i.e., the number and the distribution of pocket variants within and among populations, was significantly narrower than genetic polymorphism, indicative of a hierarchical action of selection pressures on MHC loci. 相似文献
98.
Mirko Pegoraro Shumaila Noreen Supriya Bhutani Avgi Tsolou Ralf Schmid Charalambos P. Kyriacou Eran Tauber 《PloS one》2014,9(1)
Genetic variations in circadian clock genes may serve as molecular adaptations, allowing populations to adapt to local environments. Here, we carried out a survey of genetic variation in Drosophila cryptochrome (cry), the fly’s dedicated circadian photoreceptor. An initial screen of 10 European cry alleles revealed substantial variation, including seven non-synonymous changes. The SNP frequency spectra and the excessive linkage disequilibrium in this locus suggested that this variation is maintained by natural selection. We focused on a non-conservative SNP involving a leucine - histidine replacement (L232H) and found that this polymorphism is common, with both alleles at intermediate frequencies across 27 populations surveyed in Europe, irrespective of latitude. Remarkably, we were able to reproduce this natural observation in the laboratory using replicate population cages where the minor allele frequency was initially set to 10%. Within 20 generations, the two allelic variants converged to approximately equal frequencies. Further experiments using congenic strains, showed that this SNP has a phenotypic impact, with variants showing significantly different eclosion profiles. At the long term, these phase differences in eclosion may contribute to genetic differentiation among individuals, and shape the evolution of wild populations. 相似文献
99.
Panagiotis Stathopoulos Serafim Papas Charalambos Pappas Vassilios Mousis Nisar Sayyad Vassiliki Theodorou Andreas G. Tzakos Vassilios Tsikaris 《Amino acids》2013,44(5):1357-1363
Alkylation of sensitive amino acids during synthesis of biologically important peptides is a common and well-documented problem in Fmoc-based strategy. Herein, we probed for the first time an unexpected S-alkylation of Cys-containing peptides that occur during the final TFA cleavage of peptides from the Wang solid support. Through a battery of approaches (NMR, UV and LC–MS) the formed by-product was assigned as the alkylation of the cysteine sulfydryl group by the p-hydroxyl benzyl group derived from the acidic Wang linker decomposition. Factors affecting this side reaction were monitored and a protocol that minimizes the presence of the by-product is reported. 相似文献
100.
Christos Hadjichristodoulou Spyros Pournaras Maria Mavrouli Andriani Marka Persefoni Tserkezou Agoritsa Baka Charalambos Billinis Antonios Katsioulis Anna Psaroulaki Anna Papa Nikos Papadopoulos Zissis Mamuris Athanasios Tsakris Jenny Kremastinou MALWEST Project 《PloS one》2015,10(11)
Cases of West Nile Virus (WNV) disease were recorded for three consecutive years in Greece following the year 2010 outbreak. A cross-sectional serologic survey was conducted to estimate the WNV seroprevalence and assess the ratio of infection to neuroinvasive disease. A stratified left-over sampling methodology was used including age and residence strata. A total of 3,962 serum samples was collected and tested for WNV Immunoglobulin G (IgG) antibodies by Enzyme–Linked Immunosorbent Assay (ELISA). All positive samples were further tested by Plaque Reduction Neutralization Test (PRNT) and WNV Immunoglobulin M (IgM) antibodies. WNV IgG antibodies were detected in 82 samples and 61 were also positive in PRNT representing a weighted seroprevalence of 2.1% (95% C.I.: 1.7–2.6) and 1.5% (95% C.I.: 1.2–2.0), respectively. Multivariable analysis showed that seroprevalence was associated with age and residence. The overall ratio of neuroinvasive disease to infected persons was estimated at 1:376 (95% C.I.: 1:421–1:338), while the elderly people had the highest ratio. This nationwide study provided valuable data regarding the epidemiology of WNV in Greece based on the fact that elderly people have higher risk of being both infected and having severe disease. 相似文献