Variability in leaf and fruit morphology and in fruit composition of chestnuts (<Emphasis Type="Italic">Castanea Sativa</Emphasis> Mill.) in the Nazilli region of Turkey

The aim of this study is to characterize 10 European chestnut (Castanea sativa Mill.) accessions which were selected among 80 accessions at the end of a selection study in Nazilli in Turkey. During the harvest periods in 2001, 2002 and 2003, European chestnut accessions were examined. Nineteen morphological, pomological and biochemical characters were used. Significant genotype×year interaction were found for all traits but one. Multivariate methods, including cluster and principal component analysis were performed to characterize the accessions. The first five principal components account for 86.44% of the total variance of all traits, indicating a high degree of correlation among the characteristics analyzed. High level of phenotypic proximity was found between the accessions N-20-2 and N-5-1 based on pomological, morphological and biochemical characteristics.     

Distribution of the hyaluronate lyase encoding gene hylB and the insertion element IS1548 in streptococci of serological group B isolated from animals and humans

The present study was performed to investigate streptococci of serological group B obtained from various sources and group B streptococcal reference strains for serotype, hyaluronate lyase enzyme activity, the occurrence of the hylB gene and the insertion sequence IS1548. All group B streptococci were identified by cultural, biochemical, and serological properties and by polymerase chain reaction amplification of species-specific parts of the 16S-23S rDNA intergenic spacer region, the 16S rRNA gene and the CAMP-factor (cfb) gene. Of the 73 group B streptococci investigated, 59 strains displayed hyaluronate lyase enzyme activity. All hyaluronate-lyase-positive strains and three phenotypically hyaluronate-lyase-negative strains had a hylB gene with an amplicon size of 3.3kb. Eleven of the 14 phenotypically hyaluronate-lyase-negative strains generated a hylB gene PCR product with a size of 4.6kb, and 10 of these strains displayed a IS1548 amplicon with a size of 0.98kb. The hyaluronate-lyase-negative isolates were mainly observed among group B streptococci of serotype III/Rib. All strains harbouring IS1548 had an additional copy of IS1548 located downstream of the C5a peptidase (scpB) gene.     

Nephrotoxicity in rats induced by organophosphate insecticide methidathion and ameliorating effects of vitamins E and C

The effects of organophosphate insecticide methidathion (MD) on kidney tissue and the ameliorating effects of a combination of vitamins E and C against subchronic MD toxicity were evaluated in rats. Experimental groups were: control group (group I), 5 mg/kg body weight MD-treated group (group II), and 5 mg/kg body weight MD plus vitamin E plus vitamin C treated group (group III). The groups II and III were treated orally with MD on five days a week for four weeks. Vitamins E and C were injected at doses of 50 mg/kg body weight, i.m. and 20 mg/kg body weight, i.p., respectively, 30 min after the treatment of MD in the group III. Rats were anaesthesized and venous blood samples were collected by direct right ventricle heart puncture, in addition, the right kidney was removed for histopathological examinations and malondialdehyde (MDA) analyses after four weeks. The serum activity of cholinesterase (ChE) and the kidney level of malondialdehyde, and kidney histopathology were studied in rats. MD caused decreased ChE activity (group I: 2114 ± 63 U/L, group II: 1455 ± 100 U/L) and increased MDA level (group I: 147 ± 20.2 nmol/mg protein, group II: 236 ± 25.6 nmol/mg protein), and kidney damage in rats. Furthermore, a combination of vitamins E and C restored partially (ChE activity: 1670 ± 111 U/L, MDA level: 159 19.4 nmol/mg protein) this changes in MD-treated rats.     

A morphometric and stereological study on cervical spinal cord segment of goose

In this study, volume density of white matter and grey matter areas of cervical segment of spinal cord in adult geese weighing 3–4 kg was examined using stereological methods. 10 geese were used as material without sex discrimination. All animals underwent perfusion with 10% buffered formaldehyde. Following the perfusion, animals were kept in 10% formaldehyde for 1 week. Geese were then dissected. Cervical area of spinal cord was revealed removing cervical spine. Tissue samples were obtained from each segment of cervical area. 5 μm thick cross‐sections were taken from these tissue samples via microtome. Series of cross‐sections were obtained by sampling in the ratio of 1/250 including 12 cross‐sections from each cervical segment of every animal. Cross‐sections were stained by haematoxylin eosin. They were photographed under microscope. Volume density (volume fractions) of both whole tissue and white matter and grey matter parts in each cervical segment of spinal cord were calculated using Cavalieri’s Principle. In the study, total volume of cervical segment, volume of white matter and grey matter, and ratios of these volumes one another were assessed in goose.     

DNA Fingerprinting and Genetic Characterization of Anatolian Triticum spp. using AFLP Markers

In this study, genetic analysis of Triticum spp. was carried out using AFLP markers. Six AFLP selective combinations were scored as presence and absence of bands for all the individual samples obtained from a single seed of each accession (70 accessions); T. baeoticum (21), T. monococcum (5), T. urartu (16), T. araraticum (7), T. dicoccoides (16) and T. dicoccon (5), resulting in 506 polymorphic AFLP bands. The phylogenetic tree showed two major clusters; one was composed of T. monococcum (AA) and T. baeoticum (AA), and the other cluster included T. araraticum (AAGG), T. dicoccon (AABB), T. dicoccoides (AABB), and T. urartu (AA). T. urartu, although having a diploid AA genome, did not cluster with other A genome diploids such as T. monococcum and T. baeoticum; instead it clustered together with the tetraploid species, confirming that T. urartu is the A genome progenitor. The extent of variations within and among species is discussed.     

Comparison of antioxidant and antimicrobial activities of tilia (Tilia argentea Desf ex DC), sage (Salvia triloba l.), and black tea (Camellia sinensis) extracts

The antioxidant activity of the water extract of Tilia argentea Desf ex DC was determined by the thiocyanate method. The antioxidant activity of the water extract increased with the increasing amount of lyophilized extract (50-400 microg) added into the linoleic acid emulsion. Statistically significant effect was determined in 100 microg and higher amounts. Antioxidant activities of water extracts of tilia (Tilia argentea Desf ex DC), sage (Salvia triloba L.), and two Turkish black teas commercially called Rize tea and young shoot tea (Camellia sinensis) were compared. For comparison studies, 100 microg portions of extracts were added into test samples. All samples were able to show statistically significant antioxidant effect. Both of the tea extracts showed highest antioxidant activities, nevertheless, differences between tilia and sage and tilia and tea were not statistically significant (for both cases p > 0.05). Like antioxidant activity, the reducing power of water extract of Tilia argentea Desf ex DC was also concentration dependent. Even in the presence of 50 microg of extract, the reducing power was significantly higher than that of the control (p < 0.05) in which there was no extract. Unlike antioxidant activity, the highest reducing power activity was shown by sage extract. Among the tea extracts, young shoot extract was the most effective one, however, it had significantly lower activity than sage (p < 0.05). Although tea flower had the lowest reducing power activity, it was higher than that of tilia. But this difference was not statistically significant (p > 0.05). From these results, we could suggest that although the reducing power of a substance may be an indicator of its potential antioxidant activity, there may not always be a linear correlation between these two activities. In addition, antimicrobial activities of each of the above extracts were studied by disk diffusion methods on different test microorganisms. None of the extracts showed antibacterial activity on the studied microorganisms.     

SynCAM,a synaptic adhesion molecule that drives synapse assembly

Synapses, the junctions between nerve cells through which they communicate, are formed by the coordinated assembly and tight attachment of pre- and postsynaptic specializations. We now show that SynCAM is a brain-specific, immunoglobulin domain-containing protein that binds to intracellular PDZ-domain proteins and functions as a homophilic cell adhesion molecule at the synapse. Expression of the isolated cytoplasmic tail of SynCAM in neurons inhibited synapse assembly. Conversely, expression of full-length SynCAM in nonneuronal cells induced synapse formation by cocultured hippocampal neurons with normal release properties. Glutamatergic synaptic transmission was reconstituted in these nonneuronal cells by coexpressing glutamate receptors with SynCAM, which suggests that a single type of adhesion molecule and glutamate receptor are sufficient for a functional postsynaptic response.