Production of the antibiotic cyanobacterin LU-1 by Nostoc linckia CALU 892 (cyanobacterium)

Cyanobacterin LU-1, produced by Nostoc linckia CALU 892, inhibits the growth of many cyanobacteria and eukaryotic algae. The minimum effective dose of a crude preparation to Synechococcus sp. R-2 is ca 1 µg ml^?1. The antibiotic hinders cell division and light-dependent oxygen evolution in Synechococcus sp. R-2 (PCC 7942) cells. It is not active against heterotrophic bacteria and fungi, and is non-toxic to mice. Purified cyanobacterin LU-1 contains a nitrous heterocycle with sugar and phenolic substituents. Cyanobacterin LU-1 accumulates in the medium during the course of growth, although not in direct proportion to cell density. Productivity of the culture depends on temperature.     

Study of Molecular Karyotypes in Amoeboaphelidium protococcarum,the Endotrophic Parasite of Chlorophycean alga Scenedesmus

On the basis of the pulsed field gel electrophoresis (PFGE) technique, molecular karyotypes in Amoeboaphelidium protococcarum (the endotrophic parasite of chlorophycean algae, which combines protozoon- and fungus-type characters) were determined. Molecular karyotypes in the strains X1, X5, and X31, which differ in the host range and originate from Western, Central, and Eastern Euro-Asia respectively, demonstrate the intrageneric polymorphism—from 7 to 13 chDNA bands—with the estimated molecular size of 0.3–2.2 Mb were resolved, and the genome size was determined to be between 7.4 and 10.2 Mb. The molecular karyotype pattern in A. protococcarum is different from that in Protozoa. The low-grade distinction in molecular karyotypes between X1 and X5, on one hand, and high-grade distinction between X1/X5 and X31, on the other hand, makes it possible to place X31 in a separate taxon. Received: 24 June 1996 / Accepted: 1 August 1996     

Neurotransmitter and neuropeptide mechanisms responsible for the development of a withdrawal syndrome in morphine-dependent animals

The neurotransmitter and neuropeptide mechanisms responsible for the development of the morphine drug dependence and a withdrawal syndrome (WS) were studied in rats. Physical dependence and WS were found to develop against the background of restricted responsiveness of the adrenergic and dopaminergic systems. At the same time, the activity of the serotonin-, GABA-, vasopressin-, and oxytocinergic systems is suppressed at the WS. Agonists of opiate receptors, butorphanol and loperamid, were shown to improve the physical state of the animals with a WS. Similar action was found to be exerted by activators of the adrenergic system (ephedrine, phenylephrine), dopaminergic system (levoDOPA, apomorphine), and serotonergic system (tryptophan), as well as by neuropeptides, vasopressin and oxytocin.     

Macrokinetics of enzyme sorption on porous beads accompanied by complex formation with an immobilized ligand

A mathematical model has been proposed for enzyme sorption on porous beads accompanied by formation of a stable complex with an immobilized ligand. It has been experimentally verified by using the system trypsin (EC 3.2.21.4) - immobilized bovine basic polyvalent trypsin inhibitor on porous silica gel. The experimental results for kinetics of the non-specific/specific trypsin sorption on a carrier agree with the model. The value of the coefficient of trypsin diffusion in macroporous silica gel was calculated.     

Proteomic characterization of the interstitial fluid perfusing the breast tumor microenvironment: a novel resource for biomarker and therapeutic target discovery

Clinical cancer proteomics aims at the identification of markers for early detection and predictive purposes, as well as to provide novel targets for drug discovery and therapeutic intervention. Proteomics-based analysis of traditional sources of biomarkers, such as serum, plasma, or tissue lyzates, has resulted in a wealth of information and the finding of several potential tumor biomarkers. However, many of these markers have shown limited usefulness in a clinical setting, underscoring the need for new clinically relevant sources. Here we present a novel and highly promising source of biomarkers, the tumor interstitial fluid (TIF) that perfuses the breast tumor microenvironment. We collected TIFs from small pieces of freshly dissected invasive breast carcinomas and analyzed them by two-dimensional polyacrylamide gel electrophoresis in combination with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, Western immunoblotting, as well as by cytokine-specific antibody arrays. This approach provided for the first time a snapshot of the protein components of the TIF, which we show consists of more than one thousand proteins--either secreted, shed by membrane vesicles, or externalized due to cell death--produced by the complex network of cell types that make up the tumor microenvironment. So far, we have identified 267 primary translation products including, but not limited to, proteins involved in cell proliferation, invasion, angiogenesis, metastasis, inflammation, protein synthesis, energy metabolism, oxidative stress, the actin cytoskeleton assembly, protein folding, and transport. As expected, the TIF contained several classical serum proteins. Considering that the protein composition of the TIF reflects the physiological and pathological state of the tissue, it should provide a new and potentially rich resource for diagnostic biomarker discovery and for identifying more selective targets for therapeutic intervention.     

Effect of modifiers of natural biological response on the functional activity of macrophages (oncological aspect)

Induction of cytotoxicity by biological response modifiers (BRMs) is only one aspect of macrophage activation. After the use of BRMs there were other changes in the functional activity of cells and in particular their increased production or secretion of a number of growth factors. Thus, activation of macrophage antitumor activity induced by BCG vaccine was transitory while activation of growth factor production was more stable in time which finally led to increased proliferation of tumor cells. Combined use of cyclophosphamide and BCG vaccine significantly increased not only the toxicity induced by BCG vaccine but also their liberation of the growth factors. Such macrophages lost their ability to control the growth of a small number of the tumor cells cultivated in their presence. Development of ways for directed activation of macrophages aimed at elimination of the tumor cells which survived the chemotherapy should include evaluation of the combined effect of various BRMs and chemotherapeutics on both antitumor and protumor activity i. e. ability to produce the factors stimulating the tumor growth.     

Analysis of the Stridulation in Solifuges (Arachnida: Solifugae)

Stridulation in solifuges has not been investigated yet. We performed a comparative analysis of the stridulatory organs and sounds produced by juveniles of various developmental stages and adults (both sexes) of Galeodes caspius subfuscus Birula. The stridulatory organ is of similar morphology in all developmental stages. The sound that they produced was a broad frequency hissing, composed of one or two chirps with maximum at 2.4 kHz. The intensity of the sound was found to increase with body size. Otherwise, no differences were observed between stridulation in juvenile, male and female individuals. Therefore, we suggest that the stridulation in solifuges has primarily a defensive role. As solifuges are neither venomous nor unpalatable, they might imitate an accoustically aposematic organism that shares the same habitat and has similar circadian activity, e.g. vipers. It may also have an intraspecific function in reduction of cannibalistic tendencies.     

The anatomy and ultrastructure of the suctorial organ of Solifugae (Arachnida)

Solifugae possess an evertable, adhesive pedipalpal organ (suctorial organ) at the tip of the distal tarsus of each pedipalp that is unique among arachnids. When inverted inside the pedipalp, the suctorial organ is covered with two cuticular lips, a dorsal upper lip and a ventral lower lip, but it can be protruded rapidly in order to facilitate grasping prey or climbing on bushes or even climbing on smooth surfaces due to its remarkable adhesive properties. In this study, the suctorial organs of different species from old world families Galeodidae and Karschiidae and new world families Ammotrechidae and Eremobatidae were investigated by means of light microscopy, scanning and transmission electron microscopy. In all representatives, the suctorial organ is formed by an evertable, cuticular pad with a complex internal stabilizing structure. The procuticle of this pad consists of a lattice-like basal plate and numerous stalked structures connected to this basal plate. The shafts of the stalked structures are regularly organized and ramify apically. The surface of the suctorial organ is constituted of a very thin epicuticle overlaying the ramifying apices forming ridges and furrows on the ventral side of the suctorial organ.