Regeneration of begonia plantlets by direct organogenesis

The economic importance of ornamentals worldwide suggests a bright future for ornamental breeding. Rapid progress in plant molecular biology has great potentials to contribute to the breeding of novel ornamental plants utilizing recombinant DNA technology. The plant cell, tissue or organ culture of many ornamental species and their regeneration are essential for providing the material and systems for their genetic manipulation, and this is therefore the first requirement of genetic engineering. In this research, different concentration of BA (0.0, 0.5, 1.0, 2.0 mgl(-1) with NAA ( 0.0, 0.5, 1.0 mgl(-1)) and BA (0.0, 0.5, 1.0, 2.0 mgl(-1)) with IAA ( 0.0, 0.5, 1.0, mgl(-1)) were investigated to optimize regeneration of Begonia elatior cv. Toran orange. The best regeneration and growth were obtained from the media containing 2.0 mgl(-1) BA and 1.0 mgl(-1) NAA (70%) followed by 1.0 mgl(-1) BA and 0.5 mgl(-1) NAA (50%), 1.0 mgl(-1) BA and 1.0 mgl(-1) NAA (20%) in BA - NAA combination. The media with BA - IAA combination showed that the best regeneration was 0.5 mgl(-1) BA and 0.5 mgl(-1) IAA (43%) followed by 0.5 mgl(-1) BA and 1.0 mgl(-1) IAA (23%)

Dental erozyon

Dental erozyon, plak içermeyen diş yüzeyleri üzerinde içsel ve dışsal asitlerin veya şelatların etkileriyle oluşan kimyasal bir aşınmadır. İçsel ve/veya dışsal kaynaklar nedensel faktörler olarak tanımlanırken tükürük ve pelikıl gibi biyolojik faktörler, yeme ve içme alışkanlıkları ve ağız hijyeni gibi davranışsal faktörler risk altında olan hastaların belirlenmesinde değerlendirilmelidir. Dental erozyonun erken aşamada tespit edilmesi etkin stratejilerin geliştirilmesi açısından önemlidir. Koruyucu yöntemlerinin başarısı, hastanın önerileri kabulü ve işbirliğine dayanır ve bu nedenle diş hekimi diğer sağlık çalışanları ile birlikte hasta için bireysel yönetim programları tasarlamalıdır. Bu derlemenin amacı, dental erozyonun tanısı, etiyolojisi ve tedavi protokollerini anlatmaktır. Dental erosion is a chemical wear as a result of extrinsic or intrinsic acids or chelators acting on plaque-free tooth surfaces. The intrinsic and⁄or extrinsic sources of acid need to be identified as causative factors. Biological factors such as saliva and acquired pellicle, behavioural factors such as eating and drinking habits and oral hygiene should be assessed in order to identify which patients are at risk. It is important to diagnosis the dental erosion in early stage to develop effective strategies for prevention. The success of prevention methods heavily relies on patient acceptance and cooperation. For that reason, the dentists should work with other health care providers together and design an individual management programme for the patient. The aim of this article is to review the etiology, diagnosis and the management of the dental erosion

Propagation of some seedless grape cultivars trough embriyo culture [Bazi Çekirdeksiz Üzüm Çeşitlerinin Embriyo Kültüründen Yararlanilarak Çogaltilmasi]

This experiment was carried out to propagate some seedless grape cultivars through embryo culture. Berry samples of Perlette, Flame Seedless, Sultani çekirdeksiz, Pembe çekirdeksiz, 2B-56 and King's Ruby were taken once a week between 3rd and 8th weeks after full blooming. The effects of media (MS. Nitsch and E20A) were observed on the germination of ovule and embryos. The rate of germination showed some differences due to sampling periods of cultivars and culture media used. In general, the best results were obtained from samples taken after the 5th week after full bloom and on E20A medium. Over 90.1% embryo germination rate (in 2B-56) was found on this medium. As a results, a good number of plants have been obtained from embryos of seedless grapes by this technique which was proved to be useful for breeding of seedless grape

In situ localisation of axi 1 (Auxin independent) Gene in Rhizobium leguminosarum inoculated root tips of pea plants [Axi 1 (Oksinden Baimsiz) Geninin, Rhizobium leguminosarumbv., pre ile Aşanmiş Bezelye Bitkisinin Kök Uçlarindaki in situ lokalizasyonu]

Axi 1 is the only characterized auxin independent gene in tobacco plants. In this study, the effect of axi 1 gene on cortical cell division during different stages of nitrogen fixation and on the role of polar auxin transport were investigated. Root and nodule samples were taken from pea seedlings 24 hours, 48 hours, 6 days and 10 days after inoculation with R. leguminosarum PRE strain. Using in situ hybridisation, the location of the axi 1 gene expression in root and nodule tissues was identified. The results showed that in root tissues inoculated with Rhizobia, the axi 1 gene is expressed on the phloem tissue of the vascular bundle. In the 10-day-old nodule tissues, the gene expression was found in the phloem tissue, around the nodule bundle and nodule meristematic region. The results obtained indicate that also Axi 1 gene plays a role in nitrogen fixation and auxine transport

Isolation and characterization of sequences homologous to the tobacco clone axi 1 (auxin independent) from a Vicia sativa nodule cDNA library

In this research, partial nucleotide sequences of the axi 1 gene, which is related to auxin perception and transduction, isolated from Vicia sativa using cDNA library screening were investigated. Four V. sativa cDNA clones representing homologous of the tobacco axi 1 (auxin independent) cDNA clone were isolated and characterized. With sequence analysis two different clones were observed, called 10/3a and 16/3b. Sequences about 500 bp from the 5' end and 450 bp from the 3' end were determined from the 10/3a clone. The sequences from the 5' end of cDNA clone 10/3a shared about 58 % similarity at the nucleotide level and 61% identity at the polypeptide level with the sequences of the Nicotiana tabacum axi 1 cDNA clone. At the 3' end of 10/3a, 63 % similarity at the nucleotide level was observed with the clone. In 16/3b about 500 bp was sequenced from the 5' end. There was 64 % nucleotide sequence similarity and 61 % polypeptide sequence identity. Northern blot analysis showed that the size of the mRNA was about 2 kb, like that of the axi 1 isolated from tobacco. It was shown that homolog sequences of axi 1 were expressed in flowers, leaves, stems, roots and nodules of the V. sativa plants

Isolation and characterization of sequences homologous to the tobacco clone axi 1 (auxin independent) from a vicia sativa nodule cdna library [Fig (Vicia sativa) Bitkisinin Nodül cDNA Kütüphanesinden, Tütün Axi 1 (Oksinden Bagimsiz) Klonunun Homolog Dizinlerinin Izole Edilmesi ve Karakterizasyonu]

In this research, partial nucleotide sequences of the axi 1 gene, which is related to auxin perception and transduction, isolated from Vicia sativa using cDNA library screening were investigated. Four V. sativa cDNA clones representing homologous of the tobacco axi 1 (auxin independent) cDNA clone were isolated and characterized. With sequence analysis two different clones were observed, called 10/3a and 16/3b. Sequences about 500 bp from the 5' end and 450 bp from the 3' end were determined from the 10/3a clone. The sequences from the 5' end of cDNA clone 10/3a shared about 58% similarity at the nucleotide level and 61% identity at the polypeptide level with the sequences of the Nicotiana tabacum axi 1 cDNA clone. At the 3' end of 10/3a, 63 % similarity at the nucleotide level was observed with the clone. In 16/3b about 500 bp was sequenced from the 5' end. There was 64 % nucleotide sequence similarity and 61 % polypeptide sequence identity. Northern blot analysis showed that the size of the mRNA was about 2 kb, like that of the axi 1 isolated from tobacco. It was shown that homolog sequences of axi 1 were expressed in flowers, leaves, stems, roots and nodules of the V. sativa plants

Investigation of the anticancerogenic effect of the essential oil of Melissa officinalis L.

The anticancerogenic activity of the essential oil of Melissa officinalis L. against continuous cell culture of HEp-2 cells derived from human laryngeal cancer was investigated. The effects of the essential oil was compared with the anticancerogenic effects of the Methotrexate (MTX) and Vepesid. The various concentrations of MTX, Vepesid and the essential oil on cells was examined by the morphological changes they induced on the cells and by flow cytometry analysis. The oils like MTX and Vepesid induced cytopathological changes. Whilst the essential oil terminated the cells of the G1 and S phases of the cell cycle, MTX was achieve at the S and G2 phases and Vepesid of the G1 phase was observed. These results show that the essential oil obtained from the M. officinalis L. has anticancerogenic effects