Context: Bryostatins represent an important group of pharmaceutically promising substances. These compounds are produced by commensal microorganisms naturally occurring in marine invertebrates, mainly in bryozoans. The most frequently investigated substance is bryostatin-1, which is a highly oxygenated macrolide with a polyacetate backbone. Objective: The aim of this work was to summarize documented preclinical and clinical effects of bryostatin-class compounds. Methods: A literature search was made of Medline and Web of Science databases in 2012. Results and conclusion: Our review showed that bryostatins are potent agonists of protein kinase C. In addition to this, their significant antineoplastic activity against several tumor types has also been established and described. Bryostatin's anticancer activity has been proved against various cancer types. Moreover, significant results have been achieved by using bryostatin-1 in combination with other therapies, including combination with vaccine testing. Concerning other important properties that bryostatins possess, their ability to sensitize some resistant cells to chemotherapy agents, or immunoactivity and further stimulating growth of new neural connections, and enhancing effect on long-term memory are worth mentioning. In particular, some new bryostatin analogs could represent potential therapeutic agent for the treatment of cancer and other diseases in future.

An important area of physiology of the honeybee (Apis mellifera) is chemical communication between individuals and castes in the swarm, which maintains its integrity and function. The highly complex social organization of honeybees is mediated through pheromones. Releaser pheromones cause rapid changes in the behaviour of the recipient, while primer pheromones have relatively slow and long-term effects on the physiology and behaviour of the recipient. Queen retinue pheromone (QRP) is a blend of the nine compounds (9-oxo-(E)-2-decenoic acid, (R)-and (S)-9-hydroxy-(E)-2-decenoic acid, methyl p-hydroxybenzoate, 4-hydroxy-3-methyoxyphenylethanol, methyl oleate, coniferyl alcohol, palmityl alcohol, and linolenic acid) and acts as a releaser pheromone by attracting worker bees to the queen. QRP also acts as a primer pheromone by physiologically inhibiting the ovary development of worker bees. An essential component of QRP, 9-oxo-(E)-2-decenoic acid, acts as a long-distance sex pheromone. Defensive behaviour of honeybees is induced and modulated by alarm pheromones. The essential alarm pheromone component is isopentyl acetate (IPA). The unsaturated derivative of IPA, 3-methyl-2-buten-1-yl acetate, was found in colonies of Africanized honeybees. The Nasanov gland of worker bees produces a pheromone (a blend of nerol, geraniol, (E)-and (Z)-citral, nerolic acid, geranic acid and (E,E)-farnesol) that acts as an attracting signal. This pheromone is used for aggregation (during swarming). Adult worker bees also produce a substance, ethyl oleate, that has a priming effect. Ethyl oleate is produced by adult forager bees and acts as a chemical inhibitory factor to delay age at onset of foraging (the presence of older worker bees causes a delayed onset of foraging in younger individuals). Chemical cues on the surface of larvae called a brood pheromone (ethyl and methyl esters of palmitic, linoleic, linolenic, stearic, and oleic acids, E-β-ocimene) are important in the communication between brood and worker bees. This pheromone modulates the feeding behaviour of worker bees, inhibits the activation of the worker ovary, induces worker bees to cap brood cells, increases the activity of the hypopharyngeal glands of nurse bees and modulates the behavioural maturation of worker bees.

ABSTRACT:The ability to perceive the near ultraviolet part of the light spectrum (the wavelength 320-400 nm) has been detected in many bird species. This ability is an important bird sense. The ecological importance of UV perception has been studied mainly in the context of intra-and inter-sexual signalling, common species communication and also in foraging. Some birds of prey use UV reflectance in their feeding strategy: e.g., the kestrel (Falco tinnunculus), but also other birds of prey are able to recognize the presence of voles by perceiving the UV reflectance of their scent urine marks. The ability to detect the presence of prey is a common feature of birds with analogous feeding spectra in taxonomically distinct species. UV perception and its use in foraging have also been proved in predominantly herbivorous bird species. This ability is possessed both by bird species living in northern habitats and others living in tropical forests. The signalling and communication role of the UV perception is very important. The plumage of many bird species shows specific colour features -e.g., sexually different regions in plumage coloration unnoticed by the human eye. Also other body parts can have similar features -e.g., supra-orbital combs in the red grouse (Lagopus lagopus scoticus). All these characteristics are important primarily in the mate-choice decision. Birds apparently also use their ability of UV perception for recognition of their own eggs. Some bird species are able to modify plumage UV reflectance by uropygial secretions. The knowledge of all specific aspects of bird physiology can significantly help both breeders of various bird species and facilitate effective veterinary care.

Bird skin has a number of specific properties. The uropygial gland is a significant skin gland in many species. The secretion of this gland is particularly necessary for maintaining physical characteristics, including feather waterproofing. In some bird species this gland secretion has a repellent effect against potential mammalian predators; in other species it affects the final colour of feathers. In the investigated species of storks (genus Ciconia), secretions of the uropygial gland have been found to be mixtures of monoester waxes, diester waxes, triester waxes and triglycerides. Wax diesters were also found in the red knot Calidris canutus (order Charadriiformes). Lipid substances in the secretions of the rock dove (Columba livia) consist mainly of unsaturated fatty acids (59% secretion; mostly oleic acid – 37%, linoleic acid – 6% and arachidonic acid – 7%). Free fatty acids, which are decomposition products of epidermal lipids, can regulate microbial colonization of skin (e.g., by modification of pH); a shift of these values was detected in poultry in battery husbandry. Analysis of fatty acids from lipids shows the influence of age, diet, and also the relationship to feather pecking – the individual composition affects the smell and taste, and thus the attractiveness to other individuals. The antibacterial activity of skin secretions has been demonstrated. Secretions of the hoopoe (Upupa epops) have besides the function of maintenance of physical properties of feathers also a repellent effect on parasites and predators. Its active substance is a peptide bacteriocin, produced by strains of Enterococcus faecalis. This substance is active against a number of both G + and G-bacteria and helps to sustain the nest hygiene, it is also effective against Bacillus licheniformis that produces keratin-decompositing enzymes. A similar antimicrobial activity of uropygial secretion against bacteria which degrade feathers was demonstrated in the wild house finch Carpodacus mexicanus. Changes in skin microflora have been demonstrated in parrots kept for breeding in comparison with those living in the wild, which may have significance for husbandry practices and veterinary care. Passerines of the genus Pitohui and Ifrita living in New Guinea store in their skin and feather batrachotoxins, which they receive from food - beetles of the genus Choresine. These toxins are active against parasites (e.g. lice – Phthiraptera). In contrast, substances that act as potential attractants for hematophagous insects (e.g. mosquitoes of genus Culex) were found in the skin of chickens. Alcohols, ketones and diones were detected in these substances. The composition of uropygial gland secretions may be a guide in assessing the relatedness of bird species. Feather waxes can be analyzed also from old museum specimens. Lipid-enriched organelles, multigranular bodies in the epidermis mean that zebra finches (Taeniopygia castanotis) are facultatively waterproof, which appears to have a function in protecting the organism against dehydrating when water is unavailable.

Pectinatella magnifica is an invasive freshwater bryozoan with ability to produce large colonies reaching a capacity of up to several tens dm 3 . In the Protected Landscape Area and Biosphere reserve Třeboňsko the bryozoan was first found in 2003 in one mesotrophic sandpit. The species gradually spread to many other sites around the Třeboň area and at most of these locations its occurrence has invasion properties. Pectinatella expanded to some other sandpits, fishponds without intensive pisciculture. Pectinatella colonies are found mainly on submerged branches of willow trees. The differences between biomass in transects with the occurrence of shrub willow and biomass in transects without their presence were statistically significant in the total biomass weight and the number of colonies. The average weight of several colonies did not differ. The most important parameter affecting the occurrence was the low trophy of water. The water temperature is evidently an important factor affecting the seasonal dynamics of occurence. Differences in nitrogen and phosphorous content between the water outside and inside the colonies were statistically significant. The colonies also accumulate other elements, including microelements.

A basis for the identification of potential tourist development areas was defined as a combined use of the model of area load by visitors, the territorially-located database of tourist attractions, and the perception of their attractiveness by visitors. A distinctive inequality was identified in the area load and the distribution of tourist attractions. The areas of development were determined on the basis of a difference between the relative attendance and the relative attractiveness of the partial territorial units of a regular hexagonal network, sized approximately 3 km2, with a concurrent requirement of above-average total attractiveness

Amphibians are interesting animals, very often kept by aquarists and vivarists. Their ability of intraspecific chemical signalization belongs to very interesting biological features. The skin glands of anurans secrete various biologically active compounds. The pheromones are peptides consisting of various numbers of amino acid residues and their synthesis is regulated by hormones (e.g. prolactin and androgens). Similarly, the responsiveness of the vomeronasal epithelium to some of these compounds is enhanced by some hormonal substances (prolactin and oestrogen). Hypophyseal hormones, arginine vasotocin and gonadotropin-releasing hormone are involved in the humoral regulation of pheromone discharge. The storage of some compounds with pheromonal activity in a biologically inactive form was also proved. The pheromones have an important role in sexual relationships. These chemosignals increase female receptivity and are probably involved in the mate choice. The courtship pheromone signals may be conserved across related species. Chemosignals play an important role in female attraction and/or territorial announcement. In addition to sex pheromones, various neuropeptides, antimicrobial and other biologically active peptides were found in skin glands of these amphibians. The infochemical system can be disturbed by a chemical influence in the environment.

Pectinatella magnifica (Leidy 1851) is an invasive freshwater colonial animal belonging to the phylum Bryozoa. It is native to the area east of the Mississippi River, from Ontario to Florida.