Arylalkylamines inOctopus tissues

A number of phenylethylamines and indoleamines have been analyzed in the circumoesophageal ganglia and posterior salivary gland of the normal and pargyline-treated maleOctopus dofleini martini. -Phenylethylamine,m-tyramine, and tryptamine are present in the optic lobes in amounts of 3, 0.6, and 0.6 ng/g, and in the posterior salivary gland at levels of 1, 64, and 52 ng/g, respectively, in contrast to the much higher levels observed forp-tyramine, octopamine, dopamine, noradrenaline, and 5-hydroxytryptamine. Although pargyline causes a substantial increase in the content of -phenylethylamine,m-tyramine,p-tyramine, and tryptamine in the optic lobes, no significant changes are observed in the posterior salivary gland. Their relatively rapid metabolism suggests an active role for these amines in the function of nervous tissue in theOctopus.     

Biobanking residual tissues

Health-care research relies largely on human materials stored in highly specialised biorepositories. Medical translational research on tissues can be performed using a variety of resources in distinct situations. The best known is the secondary use of pathology archives where paraffin-embedded tissues are stored for diagnostic reasons. Another is collecting and storing frozen material obtained from leftover surgical diagnosis. Such residual tissues can either be used directly in research projects or used in the context of a clinical trial with new interventional medicinal products. The latter can make the regulations governing the use of these materials for medical research much more complicated. The use of residual materials is very distinct from biobanking projects for which tissue is specifically collected. This article describes the consequences of using residual human material from different sources in distinct situations and why signed informed consent is not always the preferred choice of individual countries regarding the use of residual material. In addition, signed informed consent is overdone when using residual tissues in medical research. We maintain that the opt-out system is a balanced choice if certain requirements are met, relating to sufficient transparency about using residual tissue for research, the purpose of such research and to the confidentiality of the data used in that research. Finally, the international exchange of samples can be based on the laws and regulations of the countries of origin. Respecting these form the basis of what can and cannot be done in the country where the research on the samples is being performed.     

Engineered cardiac tissues

Cardiac tissue engineering offers the promise of creating functional tissue replacements for use in the failing heart or for in vitro drug screening. The last decade has seen a great deal of progress in this field with new advances in interdisciplinary areas such as developmental biology, genetic engineering, biomaterials, polymer science, bioreactor engineering, and stem cell biology. We review here a selection of the most recent advances in cardiac tissue engineering, including the classical cell-scaffold approaches, advanced bioreactor designs, cell sheet engineering, whole organ decellularization, stem cell-based approaches, and topographical control of tissue organization and function. We also discuss current challenges in the field, such as maturation of stem cell-derived cardiac patches and vascularization.     

Cryopreservation of vascular tissues

Cryopreservation of human blood vessels may become an important tool in bypass surgery and peripheral vascular reconstruction. Ideally cryopreservation of a blood vessel should preserve functional characteristics comparable to those of fresh controls. The key advantage of cryopreservation is the fact that storage at deep subzero temperatures allows storage of structurally intact living vascular tissues for virtually infinite time. Originally developed for long-time storage of isolated cells, the techniques of cryopreservation of tissues are challenged by the fact that these are complex multicellular systems containing diverse types of cells with differing requirements for optimal preservation. Therefore, the post-thaw functional activity of vascular tissues is determined by the type of blood vessel and, in addition, by the cell packing effect. Moreover, evidence from pharmacological studies suggests that cryopreservation induces tissue specific changes in transmembrane signaling and the mechanisms coupling intracellular calcium release, sensitivity and calcium entry into the smooth muscle cells.     

Isoflavones and calcified tissues

The data about osteotropic action of isoflavones are presented in this review. Isoflavones are the compounds of phytoestrogenes group--hormone-like bioregulators of plant origin. Animal experiments as well as bone tissue and bone cells cultures investigations demonstrate anabolic effect of isoflavones on bone metabolism. Isoflavones prevent bone loss in ovariectomized animals. They inhibit bone resorbition and enhance bone formation. Because of this natural and synthetic isoflavones hold great promise in the prevention and treatment of osteoporosis. These compounds may also be effective in preventing bone loss associated with hypodynamia or immobility, ovariectomy or postmenopausal hypoestrogenia, chronic corticosteroid use, renal osteodystrophy, hyperparathyroidism and other metabolic disorders affecting the calcified tissues, including alveolar bone loss in periodontal disease as well as dental hard tissues destruction.     

Myosins of secretory tissues

Myosin has been purified from the principal pancreatic islet of catfish, hog salivary gland, and hog pituitary. Use of the protease inhibitor Trasylol (FBA Pharmaceuticals, New York) was essential in the isolation of pituitary myosin. Secretory tissue myosins were very similar to smooth muscle myosin, having a heavy chain of 200,000 daltons and light chains of 14,000 and 19,000 daltons. Salivary gland myosin cross-reacted with antibodies directed toward both smooth muscle myosin and fibroblast myosin, but not with antiskeletal muscel myosin serum. The specific myosin ATPase activity measured in 0.6 M KCl was present. Tissues associated with secretion of hormone granules contained substantial amounts of this ATPase, rat pancreatic islets having 4.5 times that of rat liver. Activation of low ionic strength myosin ATPase by actin could not be demonstrated despite adequate binding of the myosin to muscle actin and elution by MgATP. The myosins were located primarily in the cytoplasm as determined by cell fractionation and were quite soluble in buffers of low ionic strength.