Duration Of Colchicine Treatment Research Articles

Polyploidy induction by colchicine treatment in garlic (Allium sativum L.), and effects of polyploidy on some traits

The garlic plant (Allium sativum L) is a suitable indicator plant for the determination of potential genotoxic agents in the samples taken from the environment. Polyploidy has the utmost importance in horticulture for the development of new varieties with desirable morphological traits referring to plant size and vigor, leaf thickness, larger flowers with thicker petals, intense color of leaves and flowers, long lasting flowers, compactness, dwarfness and restored fertility. Polyploidy may occur naturally due to the formation of unreduced gametes or can be artificially induced by doubling the number of chromosomes in somatic cells. Usually, natural polyploid plants are unavailable, so polyploidy is induced synthetically with the help of mitotic inhibitors. Colchicine is a widely used mitotic inhibitor for the induction of polyploidy in plants during their cell division by inhibiting the chromosome segregation. The aim of this study was to determine the effect of various concentrations and duration of colchicine treatment on root length, number of roots and stomatal densities Allium sativum L.

Visualization of smaller chromosomes from unicellular microalgae

Chromosome visualization is a technique used in many modern applications such as classification, in situ hybridization and genetic improvements, etc. Algal biotechnology grew steadily into an important global industry. Dunaliella salina (Teodoresco, 1905) is a model microalgae having tremendous potential for production of carotenoids for commercial use. The chromosomal size of microalgae is very small, and techniques for karyotype analysis are still unclear. In this work, it tried to simplify the techniques and establish a detailed step-by-step protocol using Dunaliella salina as a model and proved the technique in Tetraselmis chuii (Stein, 1878) which can be reproducible. The most important points were considered in the techniques as metaphase resting, fixation, dehydration and rehydration, hydrolysis and preparation of chromosomes for microscopic observations. During standardization, various concentration and duration of colchicine treatment were tested for metaphase arrest, replaced ethanol for methanol during fixation and dehydration, used a rehydration solution before hydrolysis and observed acid, base and enzymes impact on partial hydrolysis process of the cells. Colchicine treatment was found to be species dependent, and optimum concentration was 0.1% for 6 h (h) for Dunaliella salina, and methanol proved better to dehydrate for the preservation of algal cells. The low 500 mM concentration of HCl, 30 mM KOH and 5% enzyme proved to be suitable for the hydrolysis process for algal chromosome visualization. The technique permits clear visualization and counting of the smallest chromosome from unicellular algae. This technique described detail step by step without ambiguity and steps can be adapted on a species-specific manner.

Increased Enthesopathy in Patients With Familial Mediterranean Fever

The aim of this study was to determine the frequency of enthesopathy in familial Mediterranean fever by using a newly developed sonographic method, the Madrid Sonographic Enthesitis Index (MASEI). The study included 50 consecutive patients with familial Mediterranean fever and 57 healthy sex- and age-matched control participants. Six entheseal sites (olecranon tuberosity, superior and inferior poles of the patella, tibial tuberosity, and superior and inferior poles of the calcaneus) on both lower limbs were evaluated. All sonographic findings were identified according to MASEI. Validity was analyzed by receiver operating characteristic curves. P < .05 was considered significant. Mean total enthesitis scores ± SD were 7.54 ± 4.99 for patients and 3.63 ± 3.03 for controls (P < .001). No statistically significant correlation was found between the MASEI score and familial Mediterranean fever duration or colchicine treatment duration. There was no difference between the MASEI score and the presence or absence of arthritic involvement among the patients. The area under the receiver operating characteristic curve was 0.74 (95% confidence interval, 0.649-0.839). When analyzed by sex, men with familial Mediterranean fever had significantly higher MASEI scores than women (P < .05). This study showed significant enthesopathy in patients with familial Mediterranean fever. The findings support the hypothesis that familial Mediterranean fever and spondyloarthropathy may have common inflammatory mechanisms and suggest that the MASEI scoring system can be incorporated into clinical protocols for studying patients with familial Mediterranean fever in daily practice.

Decrease in Serum Vitamin B12 Levels Under Colchicine Treatment

Dear editor,I read with interest the article by Ozlu et al. ti-tled as “Do vitamin B12 levels needed to be evalu-ated in FMF cases having long term colchicine treatment?” published in the Annals of Paediatric Rheumatology volume, issue 2, 2012. The article reported an association between log term colchi-cine use and decrease in serum vitamin B12 levels.I would like to highlight the value of regular, close vitamin B12 evaluation with not only long term but also short term colchicine use on FMF patients.We recently did a prospective study and pub-lished in Hong Kong Journal of Paediatrics in 2011 about serum vitamin B12 status on FMF patients receiving colchicine.[1] In our study the mean duration of colchicine treatment was 2.5±2.6 years that was similar <5 years group in Ozlu’s study. The mean age were 11.7±4.5 years and 10.24±4.02 yea in our and Ozlu’s study respectively. We found serum vitamin B12 levels were as low as 240 pg/ml with compared to Ozlu’s study (390 pg/ml). 40 % of our patients became vitamin B12 deficient (vitamin B12 levels

Conjunctival impression cytology and tear‐film changes in patients with familial Mediterranean fever: authors’ reply

Editor, W e would like to thank Drs Lazar & Rothkoff (2009) for their interest in our recent article, which evaluated ocular surface changes in patients with familial Mediterranean fever (FMF) (Karalezli et al. 2009). We found that despite normal tear production, the ocular surface and tear-film functions of FMF patients differ from those of healthy individuals. We concluded that these changes might be related to the chronic inflammatory nature of FMF. Drs Lazar & Rothkoff stated that ocular surface changes in FMF patients might have resulted from the colchicine treament that they received. There are few case reports in the literature that report the delay of corneal wound healing in patients with FMF who are under colchicine treatment (Biedner et al. 1977; Alster et al. 1997; Leibovitch et al. 2003a, 2003b). However, there is no prospective randomized clinical study that evaluates the effect of colchicine on the ocular surface. Leibovitch et al. (2003a, 2003b) reported that very small quantities of colchicine were secreted in tears but they could not state whether the levels that were measured were in a toxic range. Further prospective randomized control-group studies are needed to confirm the effect of colchicine on the ocular surface and its correlation with the amount and duration of colchicine treatment.

Platelet activation in patients with Familial Mediterranean Fever

Increased platelet activation and aggregation are central processes in the pathophysiology of atherosclerosis. Increased platelet activity is associated with increased platelet volume. Mean platelet volume (MPV), a determinant of platelet function, is a newly emerging risk factor for atherothrombosis. Familial Mediterranean Fever (FMF) is an autosomal recessive disease characterized by recurrent inflammatory febrile attacks of serosal and synovial membranes. Recently few studies have shown that FMF is associated with increased atherosclerosis risk. The present study was designed to evaluate levels of MPV in FMF patients compared with healthy subjects. We selected 35 FMF patients and 35 healthy control subjects matched for age, gender, and body mass index. Metabolic parameters and MPV levels were measured in all groups. Metabolic parameters were not different among the study groups (p > 0.05). The levels of MPV were significantly higher in the FMF group than in the control group (8.6 ± 0.9 fl vs 7.8 ± 0.5 fl, p = 0.001). The MPV levels were negatively correlated with duration of colchicine treatment (r = −0.40, p = 0.017). Also MPV levels showed positive correlation with delay of diagnosis (r = 0.58, p = 0.001). In conclusion, our results suggest that patients with FMF tend to have an increased platelet activation. Increased platelet activity could contribute to increasing the atherosclerotic risk in FMF patients.

Studies on the chromosome doubling of wheat pollen plants

Studies on chromosome doubling of wheat pollen plants have been conducted, and a simple and efficient procedure for increasing the chromosome doubling frequency of wheat pollen plants was developed. Culture of the pollen calli on a colchicine-containing medium before transferring them to the regeneration medium increased the chromosome doubling frequency of the plants derived from these calli. The suitable concentration of the colchicine in the medium was around 250 mg/l, and the optimum duration for the calli to stay on the colchicine-containing medium was 1 day. Under these conditions, the chromosome doubling frequency of the pollen plants was greatly increased, but the ability of the calli to differentiate green shoots was generally not affected. The ability of the calli to differentiate green shoots was lowered mainly by a long duration of colchicine treatment. When the pollen calli were transferred to the regeneration medium in two or three batches, the pollen plants derived from the second batch of calli showed significantly higher spontaneous chromosome doubling frequency than the plants derived from the first batch of calli.

Ploidy in human cleavage stage embryos after fertilization in vitro.

Chromosome preparations were made from 15 cleaved human embryos in the 2- to 12-cell stage after in-vitro fertilization. All showed two pronuclei before the first cleavage. Twelve had at least one diploid metaphase, while three had interphase nuclei only. There was no evidence of parthenogenetic haploid cleavage. As expected, the frequency of metaphases increased with duration of colchicine treatment: 25 and 55% of the cells reached metaphase after 6-13 and 16-24 hours' treatment, respectively. Cleaved embryos with 'ideal' blastomere numbers (2, 4 or 8) showed a considerably higher metaphase frequency than others. For a more detailed chromosome analysis the technique will have to be further improved. The asynchronous cleavage of blastomeres makes optimal treatment by mitogens difficult.

Ultrastructure of mouse incisor ameloblasts after vascular perfusion with colchicine.

In order to revalue the effects of colchicine on incisor secretory ameloblasts, entire mice were perfused with Krebs solution supplemented with a buffer and amino acids, through the right common carotid artery. The normal ultrastructure of the cells was maintained for 2 h with the perfusate alone. When colchicine (0.3-3.0 micrograms/ml) was added to the perfusate, it induced ultrastructural changes, such as the loss of cytoplasmic microtubules, the loss of secretory granules in Tomes' process, the abnormal accumulation and secretion of secretory granules, disarranged Golgi apparatus and the fragmentation of rough endoplasmic reticulum. Vesicles (150-400 nm in diameter) resembling immature secretory granules also accumulated, the degree of accumulation depending on the duration of colchicine treatment. The accumulation of secretory granules and these vesicles suggests that the intracellular transport system was affected by colchicine but that the production of secretory granules was continuous throughout the experimental period. The present perfusion system has enabled us to treat ameloblasts with an agent that is a useful experimental tool for elucidating cell functions, despite being lethal to animals in vivo.