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Vegetation History and Archaeobotany - A system of farming with an alternation of land use between being cultivated or left fallow as grassland (Feldgraswirtschaft) developed in southwestern...  相似文献   
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Purpose

To investigate the thickness of the retinal layers and to assess the prevalence of macular microcysts (MM) in the inner nuclear layer (INL) of patients with mitochondrial optic neuropathies (MON).

Methods

All patients with molecularly confirmed MON, i.e. Leber’s Hereditary Optic Neuropathy (LHON) and Dominant Optic Atrophy (DOA), referred between 2010 and 2012 were enrolled. Eight patients with MM were compared with two control groups: MON patients without MM matched by age, peripapillary retinal nerve fiber layer (RNFL) thickness, and visual acuity, as well as age-matched controls. Retinal segmentation was performed using specific Optical coherence tomography (OCT) software (Carl Zeiss Meditec). Macular segmentation thickness values of the three groups were compared by one-way analysis of variance with Bonferroni post hoc corrections.

Results

MM were identified in 5/90 (5.6%) patients with LHON and 3/58 (5.2%) with DOA. The INL was thicker in patients with MON compared to controls regardless of the presence of MM [133.1±7μm vs 122.3±9μm in MM patients (p<0.01) and 128.5±8μm vs. 122.3±9μm in no-MM patients (p<0.05)], however the outer nuclear layer (ONL) was thicker in patients with MM (101.4±1mμ) compared to patients without MM [77.5±8mμ (p<0.001)] and controls [78.4±7mμ (p<0.001)]. ONL thickness did not significantly differ between patients without MM and controls.

Conclusion

The prevalence of MM in MON is low (5-6%), but associated with ONL thickening. We speculate that in MON patients with MM, vitreo-retinal traction contributes to the thickening of ONL as well as to the production of cystic spaces.  相似文献   
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Methylphenidate (MPD) is one of the most prescribed drugs for alleviating the symptoms of Attention Deficit/Hyperactivity Disorder (ADHD). However, changes in the molecular mechanisms related to MPD withdrawal and susceptibility to consumption of other psychostimulants in normal individuals or individuals with ADHD phenotype are not completely understood. The aims of the present study were: (i) to characterize the molecular differences in the prefrontal dopaminergic system of SHR and Wistar strains, (ii) to establish the neurochemical consequences of short- (24 hours) and long-term (10 days) MPD withdrawal after a subchronic treatment (30 days) with Ritalin® (Methylphenidate Hydrochloride; 2.5 mg/kg orally), (iii) to investigate the dopaminergic synaptic functionality after a cocaine challenge in adult MPD-withdrawn SHR and Wistar rats. Our results indicate that SHR rats present reduced [3H]-Dopamine uptake and cAMP accumulation in the prefrontal cortex (PFC) and are not responsive to dopaminergic stimuli in when compared to Wistar rats. After a 24-hour withdrawal of MPD, SHR did not present any alterations in [3H]-Dopamine Uptake, [3H]-SCH 23390 binding and cAMP production; nonetheless, after a 10-day MPD withdrawal, the results showed a significant increase of [3H]-Dopamine uptake, of the quantity of [3H]-SCH 23390 binding sites and of cAMP levels in these animals. Finally, SHR that underwent a 10-day MPD withdrawal and were challenged with cocaine (10 mg/kg i.p.) presented reduced [3H]-Dopamine uptake and increased cAMP production. Wistar rats were affected by the 10-day withdrawal of MPD in [3H]-dopamine uptake but not in cAMP accumulation; in addition, cocaine was unable to induce significant modifications in [3H]-dopamine uptake and in cAMP levels after the 10-day withdrawal of MPD. These results indicate a mechanism that could explain the high comorbidity between ADHD adolescent patients under methylphenidate treatment and substance abuse in adult life.  相似文献   
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Sara Benedetti  Pia Bernasconi  Enrico Bertini  Elena Biagini  Giuseppe Boriani  Cristina Capanni  Nicola Carboni  Giovanna Cenacchi  Marta Columbaro  Monica D’Adamo  Adele D’Amico  Maria Rosaria D’Apice  Marianna Fontana  Alessandra Gambineri  Giovanna Lattanzi  Rocco Liguori  Nadir M Maraldi  Laura Mazzanti  Eugenio Mercuri  Tiziana Mongini  Lucia O Morandi  Iria Neri  Giovanni Nigro  Giuseppe Novelli  Michela Ortolani  Renato Pasquali  Antonella Pini  Stefania Petrini  Luisa Politano  Stefano Previtali  Lisa Pucci  Claudio Rapezzi  Giulia Ricci  Carmelo Rodolico  Paolo Sbraccia  Emanuela Scarano  Gabriele Siciliano  Stefano Squarzoni  Antonio Toscano  Liliana Vercelli  Matteo Ziacchi 《Orphanet journal of rare diseases》2012,7(1):1-3
The need for a collaborative approach to complex inherited diseases collectively referred to as laminopathies, encouraged Italian researchers, geneticists, physicians and patients to join in the Italian Network for Laminopathies, in 2009. Here, we highlight the advantages and added value of such a multidisciplinary effort to understand pathogenesis, clinical aspects and try to find a cure for Emery-Dreifuss muscular dystrophy, Mandibuloacral dysplasia, Hutchinson-Gilford Progeria and forms of lamin-linked cardiomyopathy, neuropathy and lipodystrophy.  相似文献   
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Mitochondrial autophagy, also known as mitophagy, is an autophagosome-based mitochondrial degradation process that eliminates unwanted or damaged mitochondria after cell stress. Most studies dealing with mitophagy rely on the analysis by fluorescence microscopy of mitochondrial-autophagosome colocalization. However, given the fundamental role of mitophagy in the physiology and pathology of organisms, there is an urgent need for novel quantitative methods with which to study this process. Here, we describe a flow cytometry-based approach to determine mitophagy by using MitoTracker Deep Red, a widely used mitochondria-selective probe. Used in combination with selective inhibitors it may allow for the determination of mitophagy flux. Here, we test the validity of the use of this method in cell lines and in primary cell and tissue cultures.  相似文献   
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In Greece, since 2000, the teaching of evolutionary theory is restricted solely to lower (junior) high school and specifically to ninth grade. Even though the theory of evolution is included to the 12th grade biology textbook, it is not taught in Greek upper (senior) high schools. This study presents research conducted on the conceptions of Greek students regarding issues set out in the theory of evolution after the formal completion of the teaching of the theory. The sample comprised 411 10th grade students from 12 different schools. The research results show that the students appear to have a positive view of the idea of evolution, the evolution of man, and the common origin of organisms. However, they have retained many alternative views, or else they are completely in ignorance of basic issues in evolutionary theory regarding: what is considered evolution in biology, the main mechanism of evolutionary changes in what is considered natural selection, what the theory of evolution actually explains, and what the word theory means in science. At least in Greece, these views still prevail because the theory of evolution is marginalized in the teaching of biology in Greek schools, and biology education does not help students formulate overall conceptual structures to enable them to understand the question of biological change.
Lucia PrinouEmail:
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