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101.
Scrobotă I Mocan T Cătoi C Bolfă P Mureşan A Băciuţ G 《Revue roumaine de morphologie et embryologie》2011,52(4):1305-1309
Aerobic life is connected with continuous production of free radicals, particularly reactive oxygen species (ROS). Cells posses an enzymatic and non-enzymatic antioxidant system to maintain redox homeostasis. Oxidant-antioxidant imbalance resulting in excessive accumulation of ROS is defined as oxidative stress. Oral lichen planus (OLP) is a chronic inflammation of unknown etiology. Several researchers suggest that oxidative stress is implicated in the pathogenesis of this disorder. The aim of this study was to evaluate the histopathological alterations and the status of local oxidative stress and antioxidant defense system in patients with OLP. We evaluated and compared the local levels of oxidative stress biomarkers malondialdehyde (MDA) and glutathione (GSH) in patients with OLP with that of normal controls. Increased levels of MDA and decreased levels of GSH suggest the idea of oxidative stress implication in the pathogenesis of oral lichen planus. 相似文献
102.
Gyöngyösi M Hemetsberger R Wolbank S Pichler V Kaun C Posa A Petrasi Z Petnehazy Ö Hofer-Warbinek R de Martin R Gruber F Benedek I Benedek T Kovacs I Benedek I Plass CA Charwat S Maurer G 《Stem cell reviews》2011,7(3):616-623
The aim of the present study was to investigate the changes in absolute myocardial blood flow (AMF) after intracoronary injections of mesenchymal SC (MSC) and compared to controls in closed-chest reperfused acute myocardial infarction (AMI) in pigs. Male MSCs, transiently transfected with Luciferase (Luc-MSC) were delivered (9.7 ± 1.2 x 10(6)) intracoronary in the open infarct-related artery one-week post-AMI in female pigs (group MSC), while saline was injected with the same injection rate in controls (group C). The AMF was measured immediately after, and 3, 12 and 24 h post-intracoronary Luc-MSC or saline injections. In vitro bioluminescence images and quantitative real-time TaqMan PCR measurements were performed to quantify the sex-mismatched MSCs. No difference between the groups was observed regarding the weight, heart rate, blood pressure and global ejection fraction 1-week post-AMI. The baseline AMF were similar in the groups (61.3?±?15. vs 61.1?±?12.0 ml/min). AMF was decreased significantly immediately after intracoronary MSC delivery (42.0?±?12.4 vs 57.7?±?15.7 ml/min p?=?0.013), and remained low at 3 h (40.9?±?13.4 vs 55.8?±?4.9 ml/min, p?=?0.004), 12 h (43.0?±?3.7 vs 57.8?±?5.4 ml/min, p?=?0.001) with incomplete recovery at 24 h (47.2?±?5.5 vs 62.1?±?14.1 ml/min, p?=?0.038) as compared to controls, respectively. In vitro bioluminescence displayed transfected Luc-MSCs along the proximal and mid part of the LAD, with limited number (295?±?101 sry copied/million cardiac cells) of Y-chromosome-MSCs in the infarcted area. Intracoronary injection of SCs results in immediate decrease of AMF, with delayed recovery. The delivery of the SC into the injured myocardium might be hindered by the altered coronary pressure and flow conditions. 相似文献
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Bedford R Elsabbagh M Gliga T Pickles A Senju A Charman T Johnson MH;the BASIS team 《Journal of autism and developmental disorders》2012,42(10):2208-2218
Whilst joint attention (JA) impairments in autism have been widely studied, little is known about the early development of gaze following, a precursor to establishing JA. We employed eye-tracking to record gaze following longitudinally in infants with and without a family history of autism spectrum disorder (ASD) at 7 and 13?months. No group difference was found between at-risk and low-risk infants in gaze following behaviour at either age. However, despite following gaze successfully at 13?months, at-risk infants with later emerging socio-communication difficulties (both those with ASD and atypical development at 36?months of age) allocated less attention to the congruent object compared to typically developing at-risk siblings and low-risk controls. The findings suggest that the subtle emergence of difficulties in JA in infancy may be related to ASD and other atypical outcomes. 相似文献
105.
Chamova T Florez L Guergueltcheva V Raycheva M Kaneva R Lochmüller H Kalaydjieva L Tournev I 《Journal of neurology》2012,259(5):906-911
A recent report (Vermeer et al. in Am J Hum Genet 87:813-819, 2010) implicated for the first time the ANO10 gene in the genetic basis of autosomal recessive cerebellar ataxias. One of the three described families were Roma/Gypsies from Serbia, where the affected individuals were homozygous for the truncating p.Leu384fs mutation and displayed distinct phenotypic features (Vermeer et al. in Am J Hum Genet 87:813-819, 2010). Based on the history and population genetics of the Roma/Gypsies, we hypothesised that p.Leu384fs could be another founder mutation in this population, whose identification in a larger number of genetically homogeneous patients will contribute to defining the phenotypic spectrum of the disorder. Here, we describe additional patients from neighbouring Bulgaria, outlining invariable ANO10-ataxia features and confirming global intellectual decline as part of the phenotype resulting from complete Anactomin 10 deficit. 相似文献
106.
Zacharoula Nikolakopoulou Mushfiq Hassan Shaikh Hebah Dehlawi Adina Teodora Michael-Titus Eric Kenneth Parkinson 《Toxicology letters》2013
The long chain omega-3 polyunsaturated fatty acids (PUFA) have been reported to exert anti-cancer effects. At this study we tested the effect of the omega-3 PUFA, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), on pre-malignant keratinocytes growth in the well-characterised human pre-malignant epidermal cell line, HaCaT and attempted to identify a PUFA serum antagonist. Both EPA and DHA inhibited HaCaT growth and induced apoptosis. At the 10% (v/v) foetal bovine serum (FBS) medium, limited growth inhibition (3–20% for 50 μM DHA and EPA respectively) and negligible apoptosis were observed with PUFA use. However, at 3% (v/v) FBS medium, 30–50 μM of PUFA caused impressive levels of growth inhibition (82–83% for 50 μM DHA and EPA respectively) and increase of apoptosis (8–19% increase in 72 h). None of the numerous serum growth factors present in FBS or the antioxidant n-tert-butyl-α-phenylnitrone could inhibit the PUFA-induced cytotoxicity. In contrast, bovine and human albumin (0.1–0.3%, w/v) significantly antagonized the growth inhibitory and apoptosis-inducing effects of PUFA. In conclusion, we have shown for the first time that omega-3 PUFA inhibit the growth and induce apoptosis of pre-malignant keratinocytes and identified albumin as a major antagonistic factor in serum that could limit their effectiveness at pharmacologically-achievable doses. 相似文献
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109.
Bristow D Dehaene-Lambertz G Mattout J Soares C Gliga T Baillet S Mangin JF 《Journal of cognitive neuroscience》2009,21(5):905-921
Speech is not a purely auditory signal. From around 2 months of age, infants are able to correctly match the vowel they hear with the appropriate articulating face. However, there is no behavioral evidence of integrated audiovisual perception until 4 months of age, at the earliest, when an illusory percept can be created by the fusion of the auditory stimulus and of the facial cues (McGurk effect). To understand how infants initially match the articulatory movements they see with the sounds they hear, we recorded high-density ERPs in response to auditory vowels that followed a congruent or incongruent silently articulating face in 10-week-old infants. In a first experiment, we determined that auditory-visual integration occurs during the early stages of perception as in adults. The mismatch response was similar in timing and in topography whether the preceding vowels were presented visually or aurally. In the second experiment, we studied audiovisual integration in the linguistic (vowel perception) and nonlinguistic (gender perception) domain. We observed a mismatch response for both types of change at similar latencies. Their topographies were significantly different demonstrating that cross-modal integration of these features is computed in parallel by two different networks. Indeed, brain source modeling revealed that phoneme and gender computations were lateralized toward the left and toward the right hemisphere, respectively, suggesting that each hemisphere possesses an early processing bias. We also observed repetition suppression in temporal regions and repetition enhancement in frontal regions. These results underscore how complex and structured is the human cortical organization which sustains communication from the first weeks of life on. 相似文献
110.
Missirlis F Holmberg S Georgieva T Dunkov BC Rouault TA Law JH 《Proceedings of the National Academy of Sciences of the United States of America》2006,103(15):5893-5898
Mitochondrial function depends on iron-containing enzymes and proteins, whose maturation requires available iron for biosynthesis of iron-sulfur clusters and heme. Little is known about how mitochondrial iron homeostasis is maintained, although the recent discovery of a mitochondrial ferritin in mammals and plants has uncovered a potential key player in the process. Here, we show that Drosophila melanogaster expresses mitochondrial ferritin from an intron-containing gene. It has high similarity to the mouse and human mitochondrial ferritin sequences and, as in mammals, is expressed mainly in testis. This ferritin contains a putative mitochondrial targeting sequence and an epitope-tagged version localizes to mitochondria in transfected cells. Overexpression of mitochondrial ferritin fails to alter both total-body iron levels and iron that is bound to secretory ferritins. However, the viability of iron-deficient flies is compromised by overexpression of mitochondrial ferritin, suggesting that it may sequester iron at the expense of other important cellular functions. The conservation of mitochondrial ferritin in an insect species underscores the importance of this iron-storage molecule. 相似文献