Spotted Fever Group <Emphasis Type="Italic">Rickettsiae</Emphasis> in Ticks in Cyprus

In two surveys conducted from March 1999 to March 2001 and from January 2004 to December 2006, a total of 3,950 ticks (belonging to ten different species) were collected from seven domestic and wild animals (goat, sheep, cattle, dog, fox, hare, and mouflon) from different localities throughout Cyprus. In order to establish their infection rate with Spotted Fever Rickettsiae (SFG), ticks were pooled and tested by polymerase chain reaction targeting gltA and ompA genes, followed by sequencing analysis. When tick pools tested positive, individual ticks were then tested one by one, and of the 3,950 ticks screened, rickettsial DNA was identified in 315 ticks (infection rate, 8%). Five SFG Rickettsiae were identified: Rickettsia aeschlimannii in Hyalomma marginatum marginatum, Rickettsia massiliae in Rhipicephalus turanicus and Rhipicephalus sanguineus, Rickettsia sibirica mongolotimonae in Hyalomma anatolicum excavatum, and a Rickettsia endosymbiont of Haemaphysalis sulcata (later described as Rickettsia hoogstraalii) in Haemaphysalis punctata. Two additional genes, 17 kDa and ompB, were targeted to characterize a new genotype of “Candidatus Rickettsia barbariae” genotype in R. turanicus, designated here as “Candidatus Rickettsia barbariae” Cretocypriensis. These results confirm the presence of a spectrum of SFG Rickettsiae on the island. Further studies are necessary to gain better knowledge on the epidemiology of SFG Rickettsiae in Cyprus.     

Effects of Interaction between Angiotensin I‐Converting Enzyme Polymorphisms and Lifestyle on Adiposity in Adolescent Greeks

Genetic variation in the human angiotensin I‐converting enzyme (ACE) gene has been associated with many heritable traits, including obesity. Herein, we report the results of a study of obesity‐related phenotypes and lifestyle in 1016 teen‐aged Greeks. We show that there is a strong association (p = 0.001) between subcutaneous fat and the ACE insertion/deletion (I/D) polymorphism in females, possession of genotypes containing the D allele being associated with increased fat thickness. This association is strongest in females who participate in no extra exercise and accounts for 6.5% of the phenotypic variance in fat thickness by ANOVA. The association is additive, with the mean phenotypic values in heterozygotes intermediate between the means of the two homozygotes, and the association acts at both extremes of the fat thickness distribution in a classical polygenic manner. Other ACE polymorphisms (rs4424958, rs4311) that define major haplotypes in European populations fail to provide stronger associations with the subcutaneous fat phenotype. Because ACE I/D is the polymorphism most strongly associated with circulating ACE levels in European populations, we propose that the functional allelic differences that influence circulating ACE levels also mediate the associations with the obesity‐related phenotypes studied here.     

Regulation of hyaluronan and versican deposition by growth factors in fibrosarcoma cell lines

Versican, a large chondroitin sulphate proteoglycan and hyaluronan (HA), a non-sulphated glycosaminoglycan are major constituents of the pericellular matrix. In many neoplastic tissues, changes in the expression of versican and HA affect tumour progression. Here, we analyse the synthesis of versican and hyaluronan by fibrosarcoma cells, and document how the latter is affected by PDGF-BB, bFGF and TGFB2, growth factors endogenously produced by these cells. Fibrosarcoma cell lines B6FS and HT1080 were utilised and compared with normal lung fibroblasts (DLF). The major versican isoforms expressed by DLF and B6FS cells were V0 and V1. Treatment of B6FS cells with TGFB2 showed a significant increase of V0 and V1 mRNAs. Versican expression in HT1080 cells was not significantly affected by any of the growth factors. In addition, TGFB2 treatment increased versican protein in DLF cells. HA, showed approximately a 2-fold and a 9-fold higher production in DLF cells compared to B6FS and HT1080 cells, respectively. In HT1080 cells, HA biosynthesis was significantly increased by bFGF, whereas, in B6FS cells it was increased by TGFB2 and PDGF-BB. Furthermore, analysis of HA synthases (HAS) expression indicated that HT1080 expressed similar levels of all three HAS isoforms in the following order: HAS2> HAS3> HAS1. bFGF shifted that balance by increasing the abundance of HAS1. The major HAS isoform expressed by B6FS cells was HAS2. PDGF-BB and TGFB2 showed the most prominent effects by increasing both HAS2 and HAS1 isoforms. In conclusion, these growth factors modulated, through upregulation of specific HAS isoforms, HA synthesis, secretion and net deposition to the pericellular matrix.     

Passive cigarette smoking increases isoprostane formation

Passive smoking has been demonstrated to exert a variety of deleterious effects eventually resulting in vascular damage. Isoprostanes, a reliable marker of in vivo oxidation injury, have been shown to increase in active cigarette smoking. Data for passive smoking are lacking. We were examining the isoprostane 8-epi-PGF2alpha in 12 smokers and non-smokers exposed daily to passive cigarette smoke for 12 days. Plasma samples stored at liquid nitrogen from people having been examined earlier were used. Prevalues of 8-epi-PGF2alpha are higher in cigarette smokers. Exposure to passive smoking causes a significant increase in 8-epi-PGF2alpha in non-smokers, while in smokers there is only a trendwise increase. After repeated passive smoke exposure, 8-epi-PGF2alpha in non-smokers approaches the respective values of smokers. There is a significant correlation of 8-epi-PGF2alpha to the thromboxane (plasma, serum, conversion from exogenous precursor, 11-dehydro-TXB2) parameters (MDA, HHT- conversion) examined in these patients before. The findings document a significant temporary increase in in vivo oxidation injury due to passive smoke favouring development and/or progression of vascular disease.     

Nucleocytoplasmic shuttling of the Golgi phosphatidylinositol 4-kinase Pik1 is regulated by 14-3-3 proteins and coordinates Golgi function with cell growth

The yeast phosphatidylinositol 4-kinase Pik1p is essential for proliferation, and it controls Golgi homeostasis and transport of newly synthesized proteins from this compartment. At the Golgi, phosphatidylinositol 4-phosphate recruits multiple cytosolic effectors involved in formation of post-Golgi transport vesicles. A second pool of catalytically active Pik1p localizes to the nucleus. The physiological significance and regulation of this dual localization of the lipid kinase remains unknown. Here, we show that Pik1p binds to the redundant 14-3-3 proteins Bmh1p and Bmh2p. We provide evidence that nucleocytoplasmic shuttling of Pik1p involves phosphorylation and that 14-3-3 proteins bind Pik1p in the cytoplasm. Nutrient deprivation results in relocation of Pik1p from the Golgi to the nucleus and increases the amount of Pik1p-14-3-3 complex, a process reversed upon restored nutrient supply. These data suggest a role of Pik1p nucleocytoplasmic shuttling in coordination of biosynthetic transport from the Golgi with nutrient signaling.     

Genetic variation for parental effects on the propensity to gregarise in <Emphasis Type="Italic">Locusta migratoria</Emphasis>

Background  

Environmental parental effects can have important ecological and evolutionary consequences, yet little is known about genetic variation among populations in the plastic responses of offspring phenotypes to parental environmental conditions. This type of variation may lead to rapid phenotypic divergence among populations and facilitate speciation. With respect to density-dependent phenotypic plasticity, locust species (Orthoptera: family Acrididae), exhibit spectacular developmental and behavioural shifts in response to population density, called phase change. Given the significance of phase change in locust outbreaks and control, its triggering processes have been widely investigated. Whereas crowding within the lifetime of both offspring and parents has emerged as a primary causal factor of phase change, less is known about intraspecific genetic variation in the expression of phase change, and in particular in response to the parental environment. We conducted a laboratory experiment that explicitly controlled for the environmental effects of parental rearing density. This design enabled us to compare the parental effects on offspring expression of phase-related traits between two naturally-occurring, genetically distinct populations of Locusta migratoria that differed in their historical patterns of high population density outbreak events.     

Decorin-induced growth inhibition is overcome through protracted expression and activation of epidermal growth factor receptors in osteosarcoma cells

Decorin is an established natural oncosuppressive factor whose action is being studied in detail. Recently, decorin gene therapy formulations using adenoviral vectors have been shown in several animal models with very promising results. The present study describes the first exception to the established oncosuppression model using human osteosarcoma cells. MG-63 osteosarcoma cells were found to constitutively produce decorin, and furthermore, to be resistant to decorin-induced growth arrest. On the contrary, decorin seemed to be beneficial to osteosarcoma cells because it was necessary for MG-63 cell migration and acted as a mediator, counteracting the transforming growth factor-beta2-induced cytostatic function. Efforts to determine how MG-63 cells could overcome the decorin-induced cytostatic effect established that decorin in MG-63 cells does not induce p21 expression nor does it cause protracted retraction and inactivation of the epidermal growth factor receptor. Conversely, epidermal growth factor receptor seemed to be overexpressed and continuously phosphorylated. In view of the proposed design of decorin-based anticancer therapeutic strategies, our study provides new data on pathways that cancer cells might employ to overcome the established decorin-induced growth suppression.     

Imatinib mesylate inhibits proliferation and exerts an antifibrotic effect in human breast stroma fibroblasts

Tumor stroma plays an important role in cancer development. In a variety of tumors, such as breast carcinomas, a desmoplastic response, characterized by stromal fibroblast and collagen accumulation, is observed having synergistic effects on tumor progression. However, the effect of known anticancer drugs on stromal cells has not been thoroughly investigated. Imatinib mesylate is a selective inhibitor of several protein tyrosine kinases, including the receptor of platelet-derived growth factor, an important mediator of desmoplasia. Recently, we have shown that imatinib inhibits the growth and invasiveness of human epithelial breast cancer cells. Here, we studied the effect of imatinib on the proliferation and collagen accumulation in breast stromal fibroblasts. We have shown that it blocks the activation of the extracellular signal-regulated kinase and Akt signaling pathways and up-regulates cyclin-dependent kinase inhibitor p21(WAF1), leading to the inhibition of fibroblast proliferation, by arresting them at the G(0)/G(1) phase of the cell cycle. Imatinib inhibits more potently the platelet-derived growth factor-mediated stimulation of breast fibroblast proliferation. By using specific inhibitors, we have found that this is due to the inhibition of the Akt pathway. In addition, imatinib inhibits fibroblast-mediated collagen accumulation. Conventional and quantitative PCR analysis, as well as gelatin zymography, indicates that this is due to the down-regulation of mRNA synthesis of collagen I and collagen III-the main collagen types in breast stroma-and not to the up-regulation or activation of collagenases matrix metalloproteinase 2 and matrix metalloproteinase 9. These data indicate that imatinib has an antifibrotic effect on human breast stromal fibroblasts that may inhibit desmoplastic reaction and thus tumor progression.     

Impact of peroxisome proliferator-activated receptors gamma and delta on adiposity in toddlers and preschoolers in the GENESIS Study

Peroxisome proliferator-activated receptor gamma (PPAR gamma) and peroxisome proliferator-activated receptor delta (PPAR delta) are promising candidate genes for obesity. Associations between adiposity-related phenotypes and genetic variation in PPAR gamma (Pro12Ala and C1431T), as well as PPAR delta (T+294C) were assessed in 2,102 Greek children aged 1-6 years, as part of a large-scale epidemiological study (Growth, Exercise and Nutrition Epidemiological Study In preSchoolers). In girls aged 3-4 years, the Ala12 allele was associated with higher mid-upper arm (P = 0.010) and hip (P = 0.005) circumferences, as well as subscapular (P = 0.008) and total skinfolds (P = 0.011) that explained 2.0, 3.7, 2.1, and 1.9% of the phenotypic variance, respectively, while the T1431 allele was associated with higher mean values for waist circumference (P = 0.018) and suprailiac skinfold (P = 0.017), genotype accounting for 1.6% of the variance in both phenotypes. No significant effects of PPAR delta T+294C polymorphism or the interaction of the PPAR delta and PPAR gamma variants on adiposity-related phenotypes were observed in any age group or gender. Haplotype-based analysis including both PPAR gamma polymorphisms revealed that in girls aged 3-4 years, the Ala-T haplotype was associated with higher waist (P = 0.014) and hip (P = 0.007) circumferences compared to the common Pro-C haplotype. The PPAR gamma Pro12Ala and C1431T polymorphisms are associated with increased adiposity during early childhood in a gender- and age-specific manner and independently of the PPAR delta T+294C polymorphism.     

Princeton_TIGRESS 2.0: High refinement consistency and net gains through support vector machines and molecular dynamics in double‐blind predictions during the CASP11 experiment

Protein structure refinement is the challenging problem of operating on any protein structure prediction to improve its accuracy with respect to the native structure in a blind fashion. Although many approaches have been developed and tested during the last four CASP experiments, a majority of the methods continue to degrade models rather than improve them. Princeton_TIGRESS (Khoury et al., Proteins 2014;82:794–814) was developed previously and utilizes separate sampling and selection stages involving Monte Carlo and molecular dynamics simulations and classification using an SVM predictor. The initial implementation was shown to consistently refine protein structures 76% of the time in our own internal benchmarking on CASP 7‐10 targets. In this work, we improved the sampling and selection stages and tested the method in blind predictions during CASP11. We added a decomposition of physics‐based and hybrid energy functions, as well as a coordinate‐free representation of the protein structure through distance‐binning distances to capture fine‐grained movements. We performed parameter estimation to optimize the adjustable SVM parameters to maximize precision while balancing sensitivity and specificity across all cross‐validated data sets, finding enrichment in our ability to select models from the populations of similar decoys generated for targets in CASPs 7‐10. The MD stage was enhanced such that larger structures could be further refined. Among refinement methods that are currently implemented as web‐servers, Princeton_TIGRESS 2.0 demonstrated the most consistent and most substantial net refinement in blind predictions during CASP11. The enhanced refinement protocol Princeton_TIGRESS 2.0 is freely available as a web server at http://atlas.engr.tamu.edu/refinement/ . Proteins 2017; 85:1078–1098. © 2017 Wiley Periodicals, Inc.