Alterations in the rainbow trout (Oncorhynchus mykiss) eggs exposed to ionizing radiation during induced androgenesis.

Ionizing radiation (IR) is applied to inactivate nuclear genome in the salmonid eggs to induce androgenetic development. However, it has been considered that doses of IR used to damage maternal chromosomes may also affect morphology of the eggs and decrease their developmental potential. Thus, the main goal of the present research was to assess alterations in the rainbow trout (Oncorhynchus mykiss) eggs caused by the high dose of IR administered during androgenesis. In the present research, rainbow trout eggs were irradiated with 350 Gy of X-rays, inseminated and exposed to the high hydrostatic pressure (HHP) shock to develop as androgenetic doubled haploids (DHs). The distribution of lipid droplets in the irradiated and non-irradiated rainbow trout eggs, survival rates and morphology of larvae from androgenetic and control groups were compared. It has been observed that non-irradiated and irradiated eggs exhibited altered distribution of lipid droplets. Most of the eggs before IR treatment displayed rather equal distribution of the oil droplets. In turn, majority of eggs studied after irradiation had coalesced lipid droplets, a pattern found in eggs with reduced quality. Incidences of abnormally developed larvae were more frequently observed among fish that hatched from the irradiated eggs. Observed changes suggest X-rays applied for the genetic inactivation of rainbow trout eggs may lead to decrease of their developmental competence.

Developmental competence of eggs produced by rainbow trout Doubled Haploids (DHs) and generation of the clonal lines.

Poor quality eggs produced by the fully homozygous doubled haploids (DHs) may impair generation of clonal lines in fish species. In the present research, gynogenetic development of rainbow trout (Oncorhynchus mykiss) was induced in eggs originated from the DH females. Eggs were activated with the UV-irradiated grayling (Thymallus thymallus) spermatozoa and subjected to the high hydrostatic pressure (HHP) shock to provide diploid clonal individuals. Only two of four DH females produced eggs that were successfully activated by the irradiated spermatozoa and subsequently developed into the gynogenetic embryos. Survival rates of rainbow trout from the clonal lines equalled 21.5% and 19.8% during embryogenesis and decreased after hatching to 18.6% and 14.9%, respectively. Some of the dead rainbow trout clones collected between hatching and swim-up stage were emaciated and exhibited spinal deformities including scoliosis. Provided results confirmed limited developmental competences of eggs produced by rainbow trout DH females. Clonal rainbow trout developing in such eggs exhibited reduced survival and increased frequency of the body abnormalities.

High Rate of Deformed Larvae among Gynogenetic Brown Trout (Salmo trutta m. fario) Doubled Haploids.

Mitotic gynogenesis results in the production of fully homozygous individuals in a single generation. Since inbred fish were found to exhibit an increased frequency of body deformations that may affect their survival, the main focus of this research was to evaluate the ratio of individuals with spinal deformities among gynogenetic doubled haploids (DHs) brown trout as compared to nonmanipulated heterozygous individuals. Gynogenetic development was induced by the activation of brown trout eggs by UV-irradiated homologous and heterologous (rainbow trout) spermatozoa. The subsequent exposure of the activated eggs to the high hydrostatic pressure disturbed the first cleavage in gynogenetic zygotes and enabled duplication of the maternal haploid set of chromosomes. The survival rate was significantly higher among gynogenetic brown trout hatched from eggs activated with the homologous UV-irradiated spermatozoa when compared to DHs hatched from eggs activated by the heterologous spermatozoa. More than 35% of the gynogenetic larvae exhibited body deformities, mostly lordosis and scoliosis. The percentage of malformed brown trout from the control group did not exceed 15%. The increased number of deformed larvae among DHs brown trout suggested rather a genetic background of the disease related to the fish spine deformities; however, both genetic and environmental factors were discussed as a cause of such conditions in fish.

Side effects of botulinum toxin injection for benign anal disorders.

BACKGROUND: Botulinum toxin A (BT-A) is a powerful biological toxin. Nevertheless, it has proved to be a remarkable therapeutic agent for the treatment of benign anal disorders. Higher doses of BT-A could change the outcome of treatment. It is not known whether doses of BT-A higher than 20 units of Botox (or corresponding doses of Dysport) are as safe for patients as lower doses of BT-A. METHODS: The side effects of BT-A injections in the treatment of chronic anal fissure (105 patients) and functional outlet obstruction (34 patients) were analysed prospectively. The patients received at least 25 units of Botox or 150 units of Dysport. RESULTS: The patients with chronic anal fissure complained of incontinence of flatus (one severe case and eight mild cases), incontinence of faeces (five mild cases), anal haematoma (five cases), flu-like syndrome (three cases), an acute inflammation of external anal varices (two cases), epididymitis (one case) and haemorrhoid prolapse (one case). Patients with anismus suffered from intertrigo (one case); the pain after injection lasted for 2-4 days (four cases). No life-threatening side effects after 181 injections of BT-A were observed. Most of the side effects were only transient symptoms. No significant interdependence between injection methods (injection into one or two sites) and the risk of side effects was found. CONCLUSION: Treatment with BT-A is safe. Despite the application of higher doses of BT-A in the treatment of benign anal disorders so far, no severe side effects were observed.