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Kostas Kampourakis Eirini Palaiokrassa Maria Papadopoulou Vasiliki Pavlidi Myrto Argyropoulou 《Evolution》2012,5(2):279-291
Research has shown that children usually provide teleological explanations for the features of organisms and artifacts, from
a very early age (3–4 years old). However, there is no consensus on whether teleological explanations are given in the same
manner for non-living natural objects as well. The present study aimed to document the teleological explanations of 5- to
8-year-old children for particular features (color and shape) of organisms, artifacts and non-living natural objects. In addition,
it was examined if there was any correlation between these explanations and children’s explanations for the usefulness of
those features. Our results indicate a developmental shift in children’s teleological explanations, from a non-selective teleology
in pre-school to a selective one in the second grade. In the latter case, children provided teleological explanations mostly
for the shape of the feet of organisms and for the shape of artifacts, whereas pre-school children provided teleological explanations
for non-living natural objects as well, both for the color and for the shape in all cases. Our results are not conclusive
and further research is required, including a larger spectrum of students, since teleology is one of the most important conceptual
obstacles in understanding evolution that persists even into adulthood. We conclude by proposing a particular research program
for this purpose. 相似文献
34.
Ingrid L. C. Nieuwenhuis Vasiliki Folia Christian Forkstam Ole Jensen Karl Magnus Petersson 《PloS one》2013,8(6)
Grammar acquisition is a high level cognitive function that requires the extraction of complex rules. While it has been proposed that offline time might benefit this type of rule extraction, this remains to be tested. Here, we addressed this question using an artificial grammar learning paradigm. During a short-term memory cover task, eighty-one human participants were exposed to letter sequences generated according to an unknown artificial grammar. Following a time delay of 15 min, 12 h (wake or sleep) or 24 h, participants classified novel test sequences as Grammatical or Non-Grammatical. Previous behavioral and functional neuroimaging work has shown that classification can be guided by two distinct underlying processes: (1) the holistic abstraction of the underlying grammar rules and (2) the detection of sequence chunks that appear at varying frequencies during exposure. Here, we show that classification performance improved after sleep. Moreover, this improvement was due to an enhancement of rule abstraction, while the effect of chunk frequency was unaltered by sleep. These findings suggest that sleep plays a critical role in extracting complex structure from separate but related items during integrative memory processing. Our findings stress the importance of alternating periods of learning with sleep in settings in which complex information must be acquired. 相似文献
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Hatzi VI Terzoudi GI Barszczewska K Makropoulos V Pantelias GE 《Molecular biology reports》2012,39(1):251-257
Glutaraldehyde (GA) is a high production volume chemical that is very reactive with a wide spectrum of medical, scientific
and industrial applications. Concerning the genotoxic and carcinogenic effect of GA, controversial results have been reported,
while in humans no studies with positive carcinogenic results for GA have been published. However, our previous study concerning
the combined effects of exposure to both GA and ionising radiation (IR) in peripheral blood lymphocytes of healthy donors
has shown that non-genotoxic doses of the chemical induces a statistically significant increase in chromosomal radiosensitivity.
The lack of information concerning the radiosensitizing potential of GA on cancerous cells triggered us to test the radiosensitizing
effect of GA on breast cancer cells (MCF7). For this purpose the G2-chromosomal radiosensitivity assay (G2-assay) was used.
The assay involves G2-phase irradiation and quantitation of the chromosomal fragility in the subsequent metaphase. The experimental
data show that 48 h exposure to GA, at doses that are not clastogenic to MCF7 breast cancer cells enhances G2-chromosomal
radiosensitivity of this cell line. In an effort to evaluate whether the observed increase in GAs-induced G2-chromosomal radiosensitization
is linked to GA-induced alterations in the cell cycle and feedback control mechanism, Mitotic Index analysis was performed.
The results have shown that such a mechanism cannot be directly related to the observed GA-induced increase in G2-chromosomal
radiosensitivity. Since increased G2-chromosomal radiosensitivity has been linked with cancer proneness, the radiosensitizing
effect of GA at non-clastogenic doses highlights its potential carcinogenic profile. 相似文献
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Ioannis Petrakis Vasiliki Mavroeidi Kostas Stylianou George Efthymiou Kostas Perakis Eleftheria Vardaki Spyridon Stratigis Kostas Giannakakis Kostas Kourouniotis George Amoiridis Andreas Plaitakis Maria Joao Saraiva Ken Ichi Yamamura Eugene Daphnis 《Transgenic research》2013,22(1):101-116
Transthyretin related amyloidosis is a nosological entity that leads to disability, diminished quality of life, all stages of chronic kidney disease and eventually death. Podocytes are polarized, highly differentiated epithelial cells important for proper nephron function. In the present study we investigated whether deposited TTRVal30Met (TTRV30M) molecules could be localized within podocytes in situ under the effect of different housing conditions (i.e. specific pathogen free [SPF] vs. non-SPF). Murine renal glomeruli from human TTRV30M (hTTRV30M) transgenic mice were examined via direct and indirect immunofluorescence techniques for the presence of hTTRV30M, murine serum amyloid P, activated caspase-3 and NPHS1. Association strength and amount of colocalization for NPHS1?ChTTRV30M, NPHS1-activated caspase-3, hTTRV30M-murine serum amyloid P were estimated. Localization of hTTRV30M in podocytes was demonstrated by immuno-electron microscopy. Renal hTTRV30M gene and NPHS1 gene expression levels were estimated. Non-SPF transgenic mice showed increased glomerular hTTRV30M deposition compared to their SPF counterparts. Furthermore increased podocytic localization of hTTRV30M was noticed in non-SPF mice. Glomerular caspase-3 activation was increased only in the non SPF housing conditions. Podocytic caspase-3 activation was increased in SPF and in non-SPF transgenic mice when compared to non transgenic controls. Environmental conditions influence glomerular deposition and podocytic localization of hTTRV30M. In this context increased caspase-3 activation occurred. 相似文献
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Anastasios Papalazarou Mary Yannakoulia Stavros A. Kavouras Vasiliki Komesidou George Dimitriadis Alexandros Papakonstantinou Labros S. Sidossis 《Obesity (Silver Spring, Md.)》2010,18(7):1348-1353
The present study was designed to evaluate the 3 year effects of a lifestyle intervention on weight loss and maintenance, dietary, and physical activity habits and eating behavior of patients following vertical banded gastroplasty (VBG). Thirty severely obese female volunteers were included in the study and they were randomly assigned to one of two intervention groups: usual care (UC) or lifestyle intervention (LS) group. Patients were followed for 3 years postoperatively. Outcome measures included weight loss, dietary habits, physical activity level (PAL), and eating behavior changes. Weight was significantly lower in the LS group after 12 months (84.4 ± 3.9 kg vs. 98.4 ± 4.4 kg, P < 0.05), 24 months (83.0 ± 3.3 vs. 101.9 ± 5.3 kg, P < 0.05), and 36 months following surgery (84.2 ± 3.3 vs. 102.5 ± 3.5 kg, P < 0.05). Repeated measures ANOVA revealed significant differences between the two groups overall and at specific time points for the PAL and TV viewing. With regard to eating behavior, the LS group scored significantly better in total Dutch Eating Behavior Questionnaire (DEBQ), Restraint Eating and External Eating scales at all postoperative time points. Similarly, significant differences were found between the two groups in dietary intake. These findings outline the importance of lifestyle intervention on weight loss and maintenance following bariatric surgery. The favorable effects of lifestyle intervention may be through adoption of healthier eating behaviors and increased physical activity. 相似文献
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Christodoulou V Messaritakis I Svirinaki E Tsatsanis C Antoniou M 《Experimental parasitology》2011,(3):279-284
Although macrophages have a microbicidal role in the immune system they themselves can be infected by pathogens. Often a simultaneous infection by more than one microbe may occur in a single cell. This is the first report of coinfection of macrophages with Toxoplasma gondii and Leishmania infantum, in vitro and in vivo. L. infantum does not cause severe disease in mice but T. gondii, RH strain, is lethal. Cell culture studies using THP-1 macrophages dually infected in vitro revealed that 4.3% harbored both parasites 24 h after infection. When mice were infected with both parasites on the same day 7.3% of the infected cells carried both parasites 7 days later. Yet, if mice were first infected with L. infantum and then with Toxoplasma (5 days post-infection) 18.7% of the macrophages hosted either parasite but concomitant infection could not be found and mice, already harboring L. infantum, survived Toxoplasma’s lethal effect. 相似文献