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81.
Perennial plant Mentha pulegium L. (pennyroyal, Lamiaceae) can be found in Europe and Mediterranean. In areas where it thrives, M. pulegium is used in nutrition and as medicinal plant. Essential oil of M. pulegium is also a frequent constituent of foods and fragrances, because of mint-like odor. Regarding the use of M. pulegium in traditional medicine and nutrition, as well as fact that essential oils are potential sources of bioactive components, this study was conducted to examine the chemical composition of essential oil of M. pulegium wild growing in Bosnia and Herzegovina and its biological activity. The chemical profile testing was made using GC/MS and GC/FID technique. Potential of cholinesterase inhibition was tested by Ellman's assay. The antioxidant activity was tested by DPPH and FRAP assay. The dominant components in analyzed oil were pulegone 54.4 %, p-menthone 14.0 % and piperitenone 12.8 %. Good antioxidant activity and moderate cholinesterase inhibition potential of tested essential oil indicates to possibility of its use in treatment of diseases related to free radicals, Alzheimer disease and as lipid protecting antioxidant.  相似文献   
82.
The evolution of species or ecotypes can occur gradually through neutral and adaptive genetic changes. To explore the influence of natural selection during early phases of divergence, morphological and ecological discontinuity and its adaptive significance were investigated in six pairs of alpine and independently evolved montane populations of Heliosperma pusillum s.l.; the latter are usually taxonomically recognised at the species rank in spite of their highly debatable taxonomic value. We tested whether environmental conditions – characterised by Landolt indicator values from vegetation surveys and temperature measurements – and morphology of alpine and montane populations differ discretely and in parallel across six population pairs. By reciprocal transplantation experiments in natural environments in two population pairs and in climate chambers for five population pairs we compared fitness of native versus non‐native individuals. Alpine and montane populations differed in environmental conditions and morphology within each pair. Morphological differentiation occurred in parallel and correlated with environmental, but not with genetic distances. In both environments, native individuals had higher establishment success and plant size. Differentiation of the independently evolved montane populations is driven by natural selection and parallel, independent adaptation in response to drought, lower irradiance and higher, less fluctuating temperatures in montane populations. Our study system exemplifies rapid, parallel evolution leading to morphologically and ecologically strongly divergent, though fully interfertile, ecotypes.  相似文献   
83.
Kv1.3 is a voltage gated potassium channel that has been implicated in pathophysiology of multiple sclerosis (MS). In the present study we investigated temporal and cellular expression pattern of this channel in the lumbar part of spinal cords of animals with experimental autoimmune encephalomyelitis (EAE), animal model of MS. EAE was actively induced in female Dark Agouti rats. Expression of Kv1.3 was analyzed at different time points of disease progression, at the onset, peak and end of EAE. We here show that Kv1.3 increased by several folds at the peak of EAE at both gene and protein level. Double immunofluorescence analyses demonstrated localization of Kv1.3 on activated microglia, macrophages, and reactive astrocytes around inflammatory lesions. In vitro experiments showed that pharmacological block of Kv1.3 in activated astrocytes suppresses the expression of proinflammatory mediators, suggesting a role of this channel in inflammation. Our results support the hypothesis that Kv1.3 may be a therapeutic target of interest for MS and add astrocytes to the list of cells whose activation would be suppressed by inhibiting Kv1.3 in inflammatory conditions.  相似文献   
84.
Purpose of this study was to investigate and compare differences in oral health awareness between Croatian and Italian urban adolescents. The sample consisted of primary school last grade students aged between 13 and 15 years, 300 children from Zagreb (Croatia) and 298 children from Bari (Italy). Oral health awareness was evaluated using a self-administered standardized questionnaire. Self-perception of oral health proved to be different between the two groups (p < 0.001). The Croatians reported that their oral health was "excellent" or "very-good" more often than the Italians (68.6% vs. 50.2%). The reasons given for visiting a dentist were different (p < 0.001). The Italians cleaned their teeth more often than the Croatians ("two or more times a day", 83.1% vs. 72.2%, p < 0.003). Wooden toothpicks were preferred by the Croatians (p < 0.001), while floss was preferred by the Italians (p = 0.03). The awareness regarding the use of fluoridated toothpaste was higher in the Italian group (95.6% vs. 72.5%, p < 0.001). The Croatians were consuming sweetened foods more often than the Italians (p < 0.001). Croatian adolescents reported more indicators of a lower level of oral health awareness than the Italians, while on the contrary Croatians had higher esteem of their oral health. Defining national preventive strategies is essential for improving adolescents' attitudes toward oral health in both countries, particularly in Croatia.  相似文献   
85.
Summary The assignment of the human prealbumin (PALB) gene to chromosome region 18q11–q12.1 has been achieved using a human genomic probe in the study of human-mouse somatic cell hybrids and by in situ hybridization. Because familial amyloidotic polyneuropathy was reported previously to be due to a mutation in prealbumin, it can be inferred that the gene for this disorder also maps to 18q11.2–q12.1.  相似文献   
86.
IntroductionThe aim of the study was to analyse genetic architecture of RA by utilizing multiparametric statistical methods such as linear discriminant analysis (LDA) and redundancy analysis (RDA).MethodsA total of 1393 volunteers, 499 patients with RA and 894 healthy controls were included in the study. The presence of shared epitope (SE) in HLA-DRB1 and 11 SNPs (PTPN22 C/T (rs2476601), STAT4 G/T (rs7574865), CTLA4 A/G (rs3087243), TRAF1/C5 A/G (rs3761847), IRF5 T/C (rs10488631), TNFAIP3 C/T (rs5029937), AFF3 A/T (rs11676922), PADI4 C/T (rs2240340), CD28 T/C (rs1980422), CSK G/A (rs34933034) and FCGR3A A/C (rs396991), rheumatoid factor (RF), anti–citrullinated protein antibodies (ACPA) and clinical status was analysed using the LDA and RDA.ResultsHLA-DRB1, PTPN22, STAT4, IRF5 and PADI4 significantly discriminated between RA patients and healthy controls in LDA. The correlation between RA diagnosis and the explanatory variables in the model was 0.328 (Trace = 0.107; F = 13.715; P = 0.0002). The risk variants of IRF5 and CD28 genes were found to be common determinants for seropositivity in RDA, while positivity of RF alone was associated with the CTLA4 risk variant in heterozygous form. The correlation between serologic status and genetic determinants on the 1st ordinal axis was 0.468, and 0.145 on the 2nd one (Trace = 0.179; F = 6.135; P = 0.001). The risk alleles in AFF3 gene together with the presence of ACPA were associated with higher clinical severity of RA.ConclusionsThe association among multiple risk variants related to T cell receptor signalling with seropositivity may play an important role in distinct clinical phenotypes of RA. Our study demonstrates that multiparametric analyses represent a powerful tool for investigation of mutual relationships of potential risk factors in complex diseases such as RA.  相似文献   
87.
The influence of electric field treatment on dedifferentiation and calli formation on rape hypocotyls was investigated. Segments, 10 mm long, of the upper part of rape (Brassica napus L., cv. Góczański) hypocotyls were stimulated by different combinations of voltage/time (1.5 V/120 h, 3 V/3 h, 10 V/15 min and 30 V/30 s) under in vitro conditions. With all electric field treatments, segments oriented with their apical part towards the cathode produced more calli as compared to control (non-treated with electric field). Under opposite orientation slight inhibition of callus growth was observed. As the strongest effect on callus growth was observed after treatment with 30 V/30 s, this electric field treatment was selected for following analyses: the incorporation of [14C]-2,4-D (2,4-dichlorophenoxyacetic acid) and [14C]-BAP (benzylaminopurine) from the culture medium, changes in ACC (1-aminocyclopropane-1-carboxylic acid) level and the redox activity in apical and bottom parts of hypocotyls during 18 d of culture. In contrast to changes in fresh weight, electric field treatment (30 V/30 s) stimulated a higher accumulation of 2,4-D and BAP in basal parts of hypocotyls than in apical ones. Moreover, orienting the apical part towards the cathode resulted in lower uptake of hormones as compared with the opposite orientation. The ACC concentration increased, especially in the basal parts of hypocotyls, independently on electric field application. However, the highest level was observed after electric field treatment with orientation of the apical part towards the anode. The distribution of oxidative substances (measured as the amount of ferric ions) between the apical and bottom part of hypocotyls was not changed when the apical parts were oriented towards the cathode. Under these conditions a decrease in apical and an increase in basal parts was observed during culture. Opposite orientation influenced the redistribution of oxidative substances from the first day of electric field treatment. Based on these results we suggest that electric field action can be connected with its influence on specific concentration of oxidative substances and hormone distribution in cells.  相似文献   
88.
Adult female crabs (Neohelice granulata) were treated during the post-reproductive period with both 17-hydroxyprogesterone (17PG) and methyl farnesoate (MF). During the 4-week in vivo assay, animals were fed hormone-enriched (17PG or MF) pellets twice a week, at a dose of 2 nmol/g of body weight. Additionally, at the middle of the in vivo experiment, ovarian explants were incubated in vitro with each hormone at a concentration of 15 μM for 24 h. At the end of the in vivo assay, both the gonadosomatic index and the vitellogenic protein content (Vg) of crabs treated with either 17PG or MF were significantly higher (p < 0.05) than the values of the concurrent controls. In addition, the hemolymphatic vitellogenin level of both hormonally treated groups was higher. At the end of the in vitro assay, ovary explants incubated with 17PG had a significantly higher (p < 0.05) protein synthesis and content of Vg proteins than controls. Ovary explants incubated with MF had similar levels to controls (p > 0.05). The involvement of these hormones in the regulation of ovarian growth during the reproductive cycle of N. granulata is discussed.  相似文献   
89.
Epoxiconazole (CAS‐No. 133855‐98‐8) was recently shown to cause both a marked depletion of maternal estradiol blood levels and a significantly increased incidence of late fetal mortality when administered to pregnant rats throughout gestation (GD 7–18 or 21); estradiol supplementation prevented this epoxiconazole effect in rats (Stinchcombe et al., 2013), indicating that epoxiconazole‐mediated estradiol depletion is a critical key event for induction of late fetal resorptions in rats. For further elucidation of the mode of action, the placentas from these modified prenatal developmental toxicity experiments with 23 and 50 mg/kg bw/d epoxiconazole were subjected to a detailed histopathological examination. This revealed dose‐dependent placental degeneration characterized by cystic dilation of maternal sinuses in the labyrinth, leading to rupture of the interhemal membrane. Concomitant degeneration occurred in the trophospongium. Both placentas supporting live fetuses and late fetal resorptions were affected; the highest degree of severity was observed in placentas with late resorptions. Placental degeneration correlated with a severe decline in maternal serum estradiol concentration. Supplementation with 0.5 and 1.0 μg of the synthetic estrogen estradiol cyclopentylpropionate per day reduced the severity of the degeneration in placentas with live fetuses. The present study demonstrates that both the placental degeneration and the increased incidence of late fetal resorptions are due to decreased levels of estrogen, since estrogen supplementation ameliorates the former and abolishes the latter. Birth Defects Res (Part B) 98:208–221, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
90.
In our studies to analyze the structure/function relationships among cytoplasmic and organellar seryl-tRNA synthetases (SerRS), we have characterized a Zea mays cDNA (SerZMm) encoding a protein with significant similarity to prokaryotic SerRS enzymes. To demonstrate the functional identity of SerZMm, the gene sequence encoding the putative mature protein was cloned. This construct complemented in vivo a temperature-sensitive Escherichia coli serS mutant strain. The mature SerZMm protein overexpressed in Escherichia coli efficiently aminoacylated bacterial tRNASer in vitro, while yeast tRNA was a poor substrate. These data identify SerZMm as an organellar maize seryl-tRNA synthetase, the first plant organellar SerRS to be cloned. The analysis of its N-terminal targeting signal suggests a mitochondrial function for the SerZMm protein in maize.  相似文献   
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