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11.
Thiol redox state (TRS) reduced and oxidized components form profiles characteristic of each of the four main types of differentiation in the sclerotiogenic phytopathogenic fungi: loose, terminal, lateral-chained, and lateral-simple, represented by Rhizoctonia solani, Sclerotinia sclerotiorum, Sclerotium rolfsii, and Sclerotinia minor, respectively. A common feature of these fungi is that as their undifferentiated mycelium enters the differentiated state, it is accompanied by a decrease in the low oxidative stress-associated total reduced thiols and/or by an increase of the high oxidative stress-associated total oxidized thiols either in the sclerotial mycelial substrate or in its corresponding sclerotium, indicating a relationship between TRS-related oxidative stress and sclerotial differentiation. Moreover, the four studied sclerotium types exhibit high activities of TRS-related antioxidant enzymes, indicating the existence of antioxidant protection of the hyphae of the sclerotium medulla until conditions become appropriate for sclerotium germination.  相似文献   
12.

Background

Osteoporosis has a multifactorial pathogenesis characterized by a combination of low bone mass and increased fragility. In our study, we focused on the effects of polymorphisms in CER1 and DKK1 genes, recently reported as important susceptibility genes for osteoporosis, on bone mineral density (BMD) and bone markers in osteoporotic women. Our objective was to evaluate the effect of CER1 and DKK1 variations in 607 postmenopausal women. The entire DKK1 gene sequence and five selected CER1 SNPs were amplified and resequenced to assess whether there is a correlation between these genes and BMD, early menopause, and bone turnover markers in osteoporotic patients.

Results

Osteoporotic women seem to suffer menopause 2 years earlier than the control group. The entire DKK1 gene sequence analysis revealed six variations. There was no correlation between the six DKK1 variations and osteoporosis, in contrast to the five common CER1 variations that were significantly associated with BMD. Additionally, osteoporotic patients with rs3747532 and rs7022304 CER1 variations had significantly higher serum levels of parathyroid hormone and calcitonin and lower serum levels of osteocalcin and IGF-1.

Conclusions

No significant association between the studied DKK1 variations and osteoporosis was found, while CER1 variations seem to play a significant role in the determination of osteoporosis and a potential predictive role, combined with bone markers, in postmenopausal osteoporotic women.
  相似文献   
13.
Gliomas are common and lethal tumors of the central nervous system (CNS). Genetic alterations, inflammatory and angiogenic processes have been identified throughout tumor progression; however, treatment still remains palliative for most cases. Biological research on parameters influencing cell survival, invasion and tumor heterogeneity identified several cytokines interfering in CNS inflammation, oxidative stress and malignant transformation, including TNF-superfamily (TNFSF) members. In this report we performed a meta-analysis of public gene-array data on the expression of a group of TNFSF ligands (BAFF, APRIL, TWEAK) and their receptors (BAFF-R, TACI, BCMA, Fn14) in gliomas. In addition, we investigated by immunohistochemistry (IHC) the tumor cells'' expression of these ligands and receptors in a series of 56 gliomas of different grade. We show that in IHC, BAFF and APRIL as well as their cognate receptors (BCMA, TACI) and Fn14 expression correlate with tumor grade. This result was not evidenced in micro-arrays meta-analysis. Finally, we detected for the first time Fn14, BAFF, BCMA and TACI in glioma-related vascular endothelium. Our data, combined with our previous report in glioma cell lines, suggest a role for these receptors and ligands in glioma biology and advance these molecules as potential markers for the classification of these tumors to the proliferative, angiogenic or stem-like molecular subtype.  相似文献   
14.
ABSTRACT

Significant transformations in the ways the ethnic “self” and its relationship to the “other” are perceived have led to the transgression of the two traditional poles (East and West) that were prevalent in the definition of Greekness since the creation of the Greek nation-state. By placing the photographs of immigrants published in the most popular local newspaper in Central Greece within their wider social and historical context, we can “see” that immigrants (a group that is perceived to be homogeneous and transcendental) constitute a new axis around which the negotiation of ethnic identity and otherness in Greece is now conducted.  相似文献   
15.
Capsule Spatial environmental modelling well predicted nesting distribution of the White stork in Southeast Europe and can be used in conservation planning with respect to climate change.

Aims To create spatial models for predicting White Stork presence and densities in the Southeast Europe to identify areas of suitable habitat for White Storks.

Methods We quantified the habitat used by nesting White storks in Southeast Europe. Using spatial modelling, we defined a set of free and available online environmental variables that predict the breeding localities of the species. We employed pseudo-absences and the kriging of the residuals in order to create predictive models of nest presence and density.

Results The presence–absence model was found to be precise in predicting the presence of nests. Both density and presence of breeding pairs were best explained negatively by elevation, slope, minimum temperature during May, and distance to the nearest human settlement and positively by topographic wetness index, total area of human settlement and spring precipitation.

Conclusion Our robust and easily repeatable models offer a conservation tool to reveal suitable but unoccupied localities for breeding White Storks pairs which may inform our understanding of how climate change might affect the species' distribution in the future. For example, protecting White Storks on the Dalmatian coast may become even more significant in the future, because the Dalmatian coast is predicted as the only suitable breeding area in Croatia later this century.  相似文献   
16.
In order to improve clinical management and prevention of viral infections in hospitalised children improved etiological insight is needed. The aim of the present study was to assess the spectrum of respiratory viral pathogens in children admitted to hospital with acute respiratory tract infections in Cyprus. For this purpose nasopharyngeal swab samples from 424 children less than 12 years of age with acute respiratory tract infections were collected over three epidemic seasons and were analysed for the presence of the most common 15 respiratory viruses. A viral pathogen was identified in 86% of the samples, with multiple infections being observed in almost 20% of the samples. The most frequently detected viruses were RSV (30.4%) and Rhinovirus (27.4%). RSV exhibited a clear seasonality with marked peaks in January/February, while rhinovirus infections did not exhibit a pronounced seasonality being detected almost throughout the year. While RSV and PIV3 incidence decreased significantly with age, the opposite was observed for influenza A and B as well as adenovirus infections. The data presented expand our understanding of the epidemiology of viral respiratory tract infections in Cypriot children and will be helpful to the clinicians and researchers interested in the treatment and control of viral respiratory tract infections.  相似文献   
17.
Preeclampsia (PE) is a serious medically important disorder of human pregnancy, which features de novo pregnancy-induced hypertension and proteinuria. The severe form of PE can progress to eclampsia, a convulsive, life-threatening condition. When placental growth and perfusion are abnormal, the placenta experiences oxidative stress and subsequently secretes abnormal amounts of certain pro-angiogenic factors (eg, PlGF) as well as anti-angiogenic factors (eg, sFlt-1) that enter the maternal circulation. The net effect is damage to the maternal vascular endothelium, which subsequently manifests as the clinical features of PE. Other than delivery of the fetus and placenta, curative treatments for PE have not yet been forthcoming, which reflects the complexity of the clinical syndrome. A major source of reactive oxygen species that contributes to the widespread maternal vascular endothelium damage is the PE-affected decidua. The role of decidua-derived mesenchymal stem/stromal cells (MSC) in normotensive and pathological placenta development is poorly understood. The ability to respond to an environment of oxidative damage is a “universal property” of MSC but the biological mechanisms that MSC employ in response to oxidative stress are compromised in PE. In this review, we discuss how MSC respond to oxidative stress in normotensive and pathological conditions. We also consider the possibility of manipulating the oxidative stress response of abnormal MSC as a therapeutic strategy to treat preeclampsia.  相似文献   
18.
We have characterized in vivo and in vitro the recently identified DsbG from Escherichia coli. In addition to sharing sequence homology with the thiol disulfide exchange protein DsbC, DsbG likewise was shown to form a stable periplasmic dimer, and it displays an equilibrium constant with glutathione comparable with DsbA and DsbC. DsbG was found to be expressed at approximately 25% the level of DsbC. In contrast to earlier results (Andersen, C. L., Matthey-Dupraz, A., Missiakas, D., and Raina, S. (1997) Mol. Microbiol. 26, 121-132), we showed that dsbG is not essential for growth and that dsbG null mutants display no defect in folding of multiple disulfide-containing heterologous proteins. Overexpression of DsbG, however, was able to restore the ability of dsbC mutants to express heterologous multidisulfide proteins, namely bovine pancreatic trypsin inhibitor, a protein with three disulfides, and to a lesser extent, mouse urokinase (12 disulfides). As in DsbC, the putative active site thiols in DsbG are completely reduced in vivo in a dsbD-dependent fashion, as would be expected if DsbG is acting as a disulfide isomerase or reductase. However, the latter is not likely because DsbG could not catalyze insulin reduction in vitro. Overall, our results indicate that DsbG functions primarily as a periplasmic disulfide isomerase with a narrower substrate specificity than DsbC.  相似文献   
19.
Nuclei from Bactrocera oleae and Ceratitis capitata larvae contain a major protein that shares most of the characteristics of vertebrate high mobility group (HMG) proteins. Proteins are extracted from nuclei with 0.35 M NaCl, are soluble in 5% perchloric acid, are relatively small (molecular weight in the range of 10–16 kDa), and have both a high basic and a high acidic amino acid content. The amino acid constitution of these proteins is similar to that of the HMGB protein family of vertebrates. The proteins cross-react with antibodies raised against the HMGD chromosomal protein of Drosophila melanogaster. The possible relatedness of these proteins to high mobility group proteins is discussed.  相似文献   
20.
Aims: To evaluate food choice and eating difficulty experienced by older Greek edentate patients. Subjects: Three samples of patients seeking provision of replacement dentures were studied. A primary study of urban mainland U1 (n=54) and island rural R1 samples (n=84) was followed by a mainland urban U2 sample (n=119) in the Secondary study. Setting: Greek dental clinics. Intervention: Semi‐structured interviews (SSI) were employed, using both open and closed questions. Design: The primary study used SSI to identify eating difficulty experienced by two culturally different Greek groups. The secondary study established patterns of difficulty for comparisons between an urban Greek population and northern European urban studies. Main Outcome Measures: The prevalence of eating difficulty, the degree of difficulty eating specified foods and the exclusion of foods because difficult. Results: Most patients expressed difficulty eating at least one type of food, a high percentage of these patients were willing to eat foods found difficult, while others use particular methods of food preparation that make food easier to eat. Chicken illustrated the importance of specifying the method of cooking when questioning eating difficulties. Roast meats provided insight into the more difficult end of the food range. Raw vegetables were rated difficult. Apples and oranges were also food of particular interest. Conclusions: The semi‐structured interview method provides a succesful method to identify eating difficulty and food choices by older Greek complete denture wearers. Differences, probably largely cultural, were identified between Greek island rural and mainland urban communities. Greek food choices differed favourably from an English sample, strikingly in that Greek patients report continuing to eat difficult foods despite difficulty eating them. This may be relevant to health data on Greek populations that show better mortality statistics despite adverse factors such as high prevalence of smoking.  相似文献   
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