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Thessaloníki, Greece

Baloyannis S.J.,Aristotelian University
Journal of Alzheimer's Disease | Year: 2014

Alzheimer's disease (AD) is a progressive degeneration of the brain, inducing memory decline, inability in learning, and behavioral alterations, resulting progressively in a marked deterioration of all mental activities and eventually a vegetative state. The main causative factor, however, is still unclear. The implication of amyloid-β, AβPP, tau protein, the selective loss of neurons, the alteration of the synapses, the cytoskeletal changes, and the morphological alterations of the brain capillaries contribute substantially to the pathogenetic profile of the disease, without sufficiently enlightening the initial steps of the pathological procedures. The ultrastructure of the neuronal organelles as well as histochemical studies revealed substantial alterations, primarily concerning mitochondria. In this study, the morphological and morphometric alterations of the Golgi apparatus (GA) are described in the Purkinje cells of the cerebellum in twenty AD brains, studied with electron microscopy. As it is well established, GA has a very important role to play in many procedures such as glycosylation, sulfation, and proteolysis of protein systems, which are synthesized in the endoplasmic reticulum of nerve cells and glia. GA may also play a crucial role in protein trafficking and in misfolding of protein aggregates. In addition, the hyperphosphorylation of tau protein is closely related with the pathology of GA. In AD cases, described in this study, an obvious fragmentation of the cisternae of GA was observed in the Purkinje cells of the vermis and the cerebellar hemispheres. This alteration of GA may be associated with alterations of microtubules, impaired protein trafficking, and dendritic, spinal, and synaptic pathology, since protein trafficking plays an essential role in the three dimensional organization of the dendritic arbor and in the integrity of the synaptic components. © 2014 IOS Press.

Tzanavaras P.D.,Aristotelian University
Current Organic Chemistry | Year: 2010

Impurity profiling of active pharmaceutical ingredients is a critical quality control parameter during all stages of the development, production and stability testing of pharmaceutical formulations. Literature on this is continuously increasing, it is therefore important to keep track on the latest achievements and applications. This review presents an overview of the most recently published results on the analysis of organic impurities in pharmaceutical samples and active ingredients. Special attention is given to the most widely used techniques, such as liquid chromatography, capillary electrophoresis and mass spectrometry. © 2010 Bentham Science Publishers Ltd.

Spanos C.P.,Aristotelian University
Colorectal Disease | Year: 2012

Aim Anal skin tags are a common finding. They are found in one-third of patients with bening anal disorders. We describe a simple method of anal skin tag removal during stapled anopexy. This involves utilizing the circular anal dilator provided with the stapling kit. Method Skin tags are brought through the perforations of the circular anal dilator of the stapling kit. The skin tags are removed by cautery. Results Minimal pain has been noticed in patients under going this procedure. Conclusion Anal skin tags can be removed in a simple manner using components provided with the stapling kit. We decribe a simple method of anal skin tag removal during stapled anopexy. This involves utilizing the circular anal dilator provided with the stapling kit. © 2012 The Author. Colorectal Disease © 2012 The Association of Coloproctology of Great Britain and Ireland.

Baloyannis S.J.,Aristotelian University
Future Neurology | Year: 2015

Electron microscopy has enlarged the visual horizons of the morphological alterations in Alzheimer's disease (AD). Study of the mitochondria and Golgi apparatus in early cases of AD revealed the principal role that these important organelles play in the drama of pathogenic dialog of AD, substantially affecting energy production and supply, and protein trafficking in neurons and glia. In addition, study of the morphological alterations of the dendritic arbor, dendritic spines and neuronal synapses, which are associated with mitochondrial damage, may reasonably interpret the clinical phenomena of the irreversible decline of the mental faculties and an individual's personality changes. Electron microscopy also reveals the involvement of microvascular alterations in the etiopathogenic background of AD. © 2015 Future Medicine Ltd.

Veloukas T.,Aristotelian University | Leroch M.,University of Kaiserslautern | Hahn M.,University of Kaiserslautern | Karaoglanidis G.S.,Aristotelian University
Plant Disease | Year: 2011

Botrytis cinerea isolates (n = 122) were collected from strawberry fields located in northern Greece during a 3-year period (2008-10) and tested for their sensitivity to the succinate dehydrogenase inhibitor boscalid. Sensitivity measurements showed three distinct phenotypes consisting of isolates highly sensitive (fungicide concentration causing inhibition of germ tube growth by 50% [EC 50 values] of 0.05 to 0.21 μg ml -1), moderately resistant (EC 50 values of 1.37 to 7.79 μg ml -1), or highly resistant (EC 50 values of >50 μg ml -1) to boscalid. Sequence analysis of the sdhB gene revealed five mutations leading to amino acid substitutions in the SdhB subunit in isolates moderately resistant and highly resistant to boscalid. Three moderately resistant isolates showed a nucleotide change from A to T at codon 230, resulting in an asparagine to isoleucine (N230I) substitution. Several moderately resistant isolates showed a nucleotide change from C to T at codon 272, resulting in a substitution from histidine to arginine (H272R) whereas, in another set of isolates, a nucleotide change from A to G was found at the same codon, leading to a substitution from histidine to tyrosine (H272Y). One highly resistant isolate had a nucleotide change from A to T at codon 272, leading to a substitution from histidine to leucine (H272L), whereas, in three other highly resistant isolates, a double nucleotide change from CC to TT was observed at codon 225, resulting in a substitution from proline to phenylalanine (P225F). To facilitate rapid detection of these mutations associated with resistance to boscalid, a primer-introduced restriction analysis polymerase chain reaction was developed. The method was successfully applied to the moderately and highly resistant subpopulations and showed that the H272R mutation was predominant with relative frequencies of 28.5, 37.5, and 30% during 2008, 2009, and 2010, respectively. In contrast, the H272L mutation was detected at a frequency of 2.5% only in the 2009 population, whereas the P225F mutation was detected at a frequency of 7.5% only in the 2010 population. © 2011 The American Phytopathological Society.

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