Antifungal Thiazolidines: Synthesis and Biological Evaluation of Mycosidine Congeners

Novel derivatives of Mycosidine (3,5-substituted thiazolidine-2,4-diones) are synthesized by Knoevenagel condensation and reactions of thiazolidines with chloroformates or halo-acetic acid esters. Furthermore, 5-Arylidene-2,4-thiazolidinediones and their 2-thioxo analogs containing halogen and hydroxy groups or di(benzyloxy) substituents in 5-benzylidene moiety are tested for antifungal activity in vitro. Some of the synthesized compounds exhibit high antifungal activity, both fungistatic and fungicidal, and lead to morphological changes in the Candida yeast cell wall. Based on the use of limited proteomic screening and toxicity analysis in mutants, we show that Mycosidine activity is associated with glucose transport. This suggests that this first-in-class antifungal drug has a novel mechanism of action that deserves further study.

Evaluation of New Antimicrobial Agents Based on tris(1H-Indol-3-yl)methylium Salts: Activity, Toxicity, Suppression of Experimental Sepsis in Mice

The antimicrobial activity and toxicity of three novel synthetic antibacterial agents containing tris(1H-indol-3-yl)methylium fragment were studied in vitro and in vivo. All compounds in vitro revealed high activity (minimal inhibitory concentration (MIC) 0.13–1.0 µg/mL) against bacteria that were either sensitive or resistant to antibiotics, including multidrug-resistant clinical isolates. The derivatives combining high antimicrobial activity with relatively low cytotoxicity against human donor fibroblasts HPF-hTERT were subjected to further testing on mice. In vivo they revealed fairly good tolerance and relatively low toxicity. Acute toxicity was evaluated, and the main indicators of toxicity, including LD₅₀ and LD₁₀, were determined. A study of compounds in vivo showed their efficiency in the model of staphylococcal sepsis in mice. The efficiency of compounds may be due to the ability of indolylmethylium salts to form pores in the cytoplasmic membrane of microbial cells and thereby facilitate the penetration of molecules into the pathogen.

Synthesis and antimicrobial activity of 3,4-bis(arylthio)maleimides

A series of 3,4-bis(arylthio)maleimides were synthesized and their antimicrobial activity was evaluated against Gram-positive and Gram-negative bacteria, including multidrug resistant (MDR) strains and some fungi. Most compounds turned out to be highly active, activity being dependent on substituents on phenyl rings.

[General Brain Structure of Newly Hatched Larva and Neuroblasts in Larval Mushroom Bodies in Pterostichus niger Deg. (Coleoptera: Carabidae)]

It is revealed that the larval brain of Pterostichus niger, an active predator with well-developed long-distance sense organs (the set of antennal sensilla and lateral ocelli, or stemmata) at hatching already contains optic lobes, which include two groups of optic neuropils and complex antennal lobes of glomerular neuropil. It is shown that the central complex of the protocerebrum is represented by a bipartite protocerebral bridge and the upper part of the central body and the mushroom bodies include, numerous Kenyon cells, a well-developed calyx, a peduncular apparatus, and numerous neuroblasts.

[A novel, unusual (at least for beetles) mode of Kenyon cell production in the diving beetle Cybister laterlimarginalis Deg. (Coleoptera: Dytiscidae)]

Kenyon cell production in the mushroom bodies of Cybister lateralimarginalis is a peculiar process. It has been found that each proliferative center contains one giant neuroblast, which divides unequally, and its smaller daughter cell becomes the 2nd order neuroblast dividing unequally as well. The smaller daughter cell of this neuroblast becomes a ganglion mother cell. The latter, as usual, divides equally producing two Kenyon cells.

[Histological structure of tripartite mushroom bodies in ground beetles (Insecta, Coleoptera: Carabidae)]

Contrary to members of the suborder Polyphaga; ground beetles have been found to possess tripartite mushroom bodies, which are poorly developed in members of basal taxa and maximally elaborated in evolutionarily advanced groups. Nevertheless, they do not reach the developmental stage, which has been previously found in particular families of beetles. It has been pointed out that anew formation of the Kenyon cells occurs during at least the first months of adult life, and inactive neuroblasts are found even in one-year-old beetles. It has been suggested that there is a relation between the Kenyon cell number and development of the centers of Kenyon cell new-formation.

[Comparative histology of mushroom bodies in carnivorous beetles of the suborder polyphaga (Insecta, Coleoptera)]

Mushroom bodies in beetles of the families Histeridae, Staphylinidae, Cantharidae, Trogossitidae, Peltidae, Cleridae, Malachiidae, and Coccinellidae are shown to be rather poorly developed. The calyx region of the mushroom bodies in these beetles never forms two separate cups, and the peduncular apparatus includes a unified shaft almost over its entire length. Only the pedunculus contains two separate shafts in a few cases. Two proliferative centers consisting of one to three neuroblasts are often found in each Kenyon cell group. The shift from carnivorous to feeding on pollen or leaves, which has taken place in some taxa, does not visibly affect the degree of mushroom body development.

[The mushroom bodies of the lower nematocera: a link between those of the higher Diptera and other mecopteroids]

Nematoceran Diptera are nonuniform in the structure of their mushroom bodies. Members of the more basal families (Ptychopteridae, Pediciidae, and Tipulidae) have bipartite mushroom bodies, characteristic of members of the other mecopteroid complex orders. In members of Bibionomorpha (Bibionidae and Anisopodidae), tripartite mushroom bodies have been found characteristic of Brachycera Orthorrhapha.

[Leaf beetles (Coleoptera: Chrysomelidae): mushroom body simplification in the course of progressive evolution of the family]

Members of different subfamilies of Chrysomelidae differ strongly in the degree of mushroom body development. The mushroom bodies are especially strongly developed (with the calyx in the form of large cups and double shafts of the peduncular apparatus) in the evolutionarily primitive subfamilies Sagrinae and Criocerinae, and considerably reduced in members of more evolved subfamilies, with the calyx region weakly developed and shafts of the peduncular apparatus fused together. It is suggested that this mushroom body reduction can be related to the closer connection of the head with the prothorax, which is found in the more evolved leaf beetle subfamilies.

[Longicorn beetles (Coleoptera:Cerambycidae) differ considerably in the degree of their mushroom body development]

A duality in the general structure of the mushroom body in longicorn beetles is confirmed. This duality is associated with the fact that they are formed by two solitary neuroblasts or two neuroblast clusters on each side of the brain and are manifested as a bipartite structure of both the calyx, which is the main sensory input, and the peduncular apparatus. Within the studied longicorn beetles, modifications in the general structure of mushroom bodies have been found; these modifications are caused by two oppositely directed morphogenetic processes, namely, the concentration of structures and their compartmentalization. The concentration leads to disappearance of the bipartite structure of the peduncular apparatus, whereas compartmentalization leads to a secondary subdivision of these structures into anatomically distinct subsections. This process is most pronounced in the peduncle and lobes. The mushroom bodies are best developed and differentiated in the members of the subfamily Lamiinae.

[Diversity in neuroblasts number forming mushroom bodies of the highest dipterans (Insecta, Diptera, Brachycera Cyclorrhapha)]

Neurogenesis in mushroom bodies is studied in 12 species of the highest dipterans. A substantial difference in the number of neuroblasts forming mushroom bodies is found. In the majority of species studied, Kenyon cells are formed by four single neuroblasts. Among six calliphorid species, the number of neuroblasts increases up to 10-15 (mean 12.6) in each mushroom body in Calliphora vicina only. In young pupae of Muscina stabulans and M. livida, four polyneuroblastic prolipherate centers formed instead of singular neuroblats. These centers disintegrate into numerous single neuroblasts. A hypothesis of the origin of the polyneuroblastic structure of mushroom bodies found in C. vicina and, earlier, in Musca domestica, is proposed.

[Structure of the mushroom bodies in Scarabaeoidea (Coleoptera): II. Phytophagous Scarabaeidae and general discussion]

The mushroom body structure is progressively more complicated within the superfamily Scarabaeoidea. In the basal families and coprophagous Scarabaeidae, the calyx region is asymmetrical and poorly developed but reaches the maximal degree of development in the phytophagous Scarabaeidae of the subfamilies Melolonthinae and Cetoniinae. These Scarabaeidae have two separate calyces; moreover, some species have additional regions of glomerular neuropile. The processes of different Kenyon cell types segregate into special subdivisions of vertical and medial lobes. It is assumed that a progressive development of the mushroom body in phytophagous Scarabaeidae is associated with the need to integrate olfactory and visual information.

[Interhemisphere asymmetry of the CSF dynamics and biomechanical properties of the skull]

This investigation shows that both intracranial liquor circulation and skull biomechanical properties evaluated by its pliability (compliance) to intracranial pressure are characterised by marked interhemisphere asymmetry. The interhemisphere differences of cerebrospinal fluid mobility were evaluated by means of asymmetry coefficient (right/left ratio of liquor mobility) which was found to be 1.25-1.45 in healthy middle-age persons. For the skull pliability (compliance) the coefficient of hemispheric asymmetry was 0.75-0.95. These two hemisphere asymmetry coefficients are characterized by reciprocal relationships. These coefficients demonstrated no dominancy related to right/left hemisphere as well as no correlation with neurophysiological parameter. Functional tests (apnoea, hyperventilation, Stookey test) gave rise to significant changes of these coefficient values. At ageing, the magnitudes of these coefficients decreased. The spectral analysis of pulse waves of dopplerogram and rheoencephalogram reveals hemisphere asymmetry, too. It should be suggested that the interhemisphere asymmetry of the CSF dynamics and skull biomechanical properties is a special mechanism which contributes in the process of circulatory-metabolic support of brain activity.

[Structure of the mushroom-like bodies in lamellar-antennae beetles (Coleoptera: Scarabaeoidea). 1. Basal families and coprophagy Scarabaeoidea]

Mushroom bodies are in general similarly developed in most taxons studied. The calyx region appears as a single structure, and its dual nature is not yet realized. An anterio-posterior asymmetry of the calyx region with Kenyon cell processes running mostly behind the glomerular neuropil of the calyx is characteristic of all the species studied. In this respect, the calyx region of basal Scarabaeoidea resembles greatly the calyx of many dipterans. Lobe compartmentalization occurs at the initial stage. The passalid beetles represent an exception, as their mushroom bodies are much more developed than in related families. This may be connected with the complicated social behavior of Passalidae.

[How many neuroblasts build mushroom bodies in Lucilia caesar L. and Musca domestica L. (Diptera, Brachycera Cyclorrhapha)?]

The green-bottle fly Lucilia caesar and the housefly Musca domestica differ greatly in the number of neuroblasts producing mushroom bodies. Four neuroblasts were found in each mushroom body of Lucilia pupae, and its calyx has a quadruple structure. In the housefly, the number of mushroom body neuroblasts rises up 20 in each brain hemisphere. This leads to a more complicated calyx structure. The neuroblast number observed in Lucilia and Musca is compared with that found in other Diptera.

[Effect of transcranial electrostimulation on clinical and laboratory characteristics in patients with gastric ulcer]

The study included 100 patients with gastric ulcer aged from 16 to 60 years. In 58 patients, traditional treatment was supplemented by transcranial electrotherapy using a TRANSAIR-02 apparatus. Laboratory studies included measurements of lactoferrin (LF) and tumour necrosis factor-alpha (TNF-alpha), besides standard analyses. Combined treatment (traditional therapy plus electrostimulation) resulted in a significant reduction in duration of the main symptoms of the gastric ulcer depending on the severity of ulceration process, patients' age and sex. Moreover, it facilitated ulcer scarring and had beneficial effect on dynamics of serum LF and TNF-alpha levels.

[General structure of the mushroom body calyx in brachycera orthorrhapha flies (Diptera)]

The mushroom body calyx in Brachycera Orthorrhapha flies is extremely diverse in the degree of development. In general, the calyx has the anterior, posterior, and dorsal lobes, as well as "sleeves" of glomerular neuropil surrounding Kenyon cell fibers. The anterior lobe of the calyx is found in all species studied. The most complex structure of the calyx is characteristic of the families Empididae and especially Bombyliidae, in which it has all the parts listed above. Brachycera Orthorrhapha flies have three fiber bundles of Kenyon cells, in contrast to four bundles in Drosophila flies. It is assumed that each mushroom body in Brachycera Orthorrhapha flies is formed by descendants of three single neuroblasts.

[Application of transcranial electrostimulation in the complex treatment of gastric ulcer]

Transcranial electrotherapy on the TRANSAIR-02 apparatus of 46 patients with stomach ulcer has been carried out. Sedation of the main symptoms of the disease after 5 procedures was noted in a considerable number of the patients. All the above mentioned symptoms were fully disappeared after 5-7 days of treatment. Using transcranial electrostimulation in complex treatment of the patients with stomach ulcer gives the possibility to decrease the terms oh being present at the station, to decrease the risk of complication and to perfect the quality of treatment.

[Amphicoma (Coleoptera, Glaphyridae): a generalist feeder with poorly developed mushroom bodies]

Amphicoma species are phytophagous generalists but have poorly developed mushroom bodies with a minute calyx and united pedunculus and lobes of concentric structure. Thus, in this respect Amphicoma are closer to the dung scarab beetles regarded as specialist feeders (Farris and Roberts, 2005).

[Biomechanical properties of the human cranium: aging aspects]

Biomechanical properties of the human skull affect its dynamic tensility (pliability, compliance) by changes of intracranial volume and pressure (deltaV/deltaP). The goal of this study is to substantiate a possibility of noninvasive and dynamic evaluation of cranial compliance. The transcranial dopplerogram of middle cerebral artery and hemispheric bioimpedance were synchronously recorded, which represent information about pulsative changes of intracranial pressure and volume, respectively. The parameters were recorded at rest and during adequate hemo- and liquorodynamic tests in different age groups--20-30, 40-50, and 70-85 years. As compared with the young group, a decrease of the cranial compliance in the intermediate age group was revealed due to an observed increase if rigidity of skull bones and ligaments, which indicates a decrease of stability of the intracranial circulatory system. However, in the group of 70-85 years the compliance rose again due to an enlargement of intracranial liquor spaces and facilitation of liquor circulation inside the intracranial cavity; this can be suggested to be a compensatory mechanism for supporting the adequate brain circulatory-metabolic state.

[Slow-wave fluctuations in craniosacral space: hemo-liquorodynamic conception of origin]

In the paper, the mechanism of forming of rhythmic slow-wave fluctuations in craniospinal cavity was investigated. In five young healthy persons, at rest and under voluntary respiration arrest test, the bioimpedansograms of head and lumbosacral part of vertebral column were synchronously registered as these recordings reflect the changes of relationships between blood/CSF volumes in cranial and lumbosacral regions, respectively. The recordings were subjected to frequency and spectral computer analysis (PC Macintosh G-4, Chart 5.2. software). The rapid (pulsatile) as well as slow and counter-directed waves (frequency 6-10 cycles/min) of these processes were revealed in cranial and lumbosacral regions. The data obtained suggest the CSF dynamic concept of origin of the craniosacral rhythm. The pulse and slow-frequency oscillations of the cerebral vessels tone initiate corresponding intracranial pressure waves, and the latter are the motivating forces for to-and-fro CSF shifts in caudal direction. This mechanism is accompanied by tonic contractions of lumbar muscles and sacrum movements, and it is manually perceptible as a craniosacral rhythm.

[Age-related characteristics of relationships between brain blood flow, liquor dynamics and biomechanical properties of human cranium]

The peculiarities of relationships between changes of cerebral blood flow, intracranial liquor dynamics and skull biomechanics in humans were studied in an age aspect. For this aim, a non-invasive method was proposed based on concomitant registration of rheoencephalogram and transcranial dopplerogram and evaluation of relationships between intracranial volume and pulse pressure changes (P-V index). The data obtained were analyzed by pattern-phase computer processing and compared with the blood flow parameters. The investigation was carried out on healthy volunteers of 18-25, 40-50 and 65-75 years of age. It was shown that circulatory-metabolic supplying of human brain was supported by such factors as volume brain blood flow, intracranial liquor dynamics in cooperation with skull biomechanics. The cerebral blood flow decrease at aging could be compensated by increase of the reserve-compensatory abilities of the system of cranial-spinal liquor dynamics.

[Studying cGMP-dependent mechanisms of vinpocetine effect on smooth muscle cells]

The results of the membrane potential measurements (by the double sucrose gap junction technique) and the smooth muscle tension determination (by the mechanical force measurements) in the rat aorta showed that vinpocetine potentiates the effect of sodium nitroprusside and nitroglycerin on the smooth muscle cells. In the concentration range of 2-20 microM, vinpocetine produced a dose-dependent inhibition of the Ca2+ conductivity of the membrane and decreased the smooth muscle contractility response. At a concentration of 1 microM, the drug acted as an inhibitor of the phosphodiestherase (PDE) activity and produced the effects similar top those of dibutyryl-cGMP (rather than dibutyryl-cAMP). In the presence of 10 microM of Methylene Blue (an inhibitor of the soluble fraction of guanylate cyclase), the cGMP-dependent effects of vinpocetine were suppressed on the background of 100 microM of sodium nitroprusside, but retained on the background of 10 microM of 3-isobutyl-1-methylxanthine (IBMX), a nonspecific PDE inhibitor. IBMX acted like dibityryl-cGMP and activated the K+ conductivity of the membrane. It is suggested that cGMP-dependent effects of vinpocetine are related to its action upon the Ca2+ and Na+ and (but not K+) conductivity and to the cGMP-induced increase in the contribution of sarcoplasmic calcium to the contractile response.

[Mechanisms of NO-dependent relaxation in smooth muscles of the rat aorta with nitro compounds]

The membrane potential and smooth muscle tension in rat aorta were studied by the method of sucrose gap junction. It was found that sodium nitroprusside and nitroglycerin produced a dose-dependent membrane repolarization and smooth muscle cell relaxation in rat aorta preliminarily contracted and depolarized by hyperpotassium (40 mM) or phenylephrine solutions. The relaxation effect of sodium nitroprusside was more pronounced on the phenylephrine background. The effect of nitroglycerin showed a different kinetics in time and led to the tolerance development. The effects of both nitro compounds were inhibited by pretreatment with Methylene Blue or potassium channel blockers. It is suggested that nitro vasodilators are involved in the NO-dependent processes in smooth muscle cells of aorta through cGMP-mediated activation of the potassium conductivity and by changing the efficiency of operation of the protein kinase C branch of the Ca2+ signal system.

Effect of nitro derivatives on electromechanical coupling in ureteral smooth muscle cells

Double sucrose gap experiments revealed differences in the effect of nitroglycerin and sodium nitroprusside on action potential and contraction of ureteral smooth muscle cells. Unlike sodium nitroprusside, nitroglycerin inhibited voltage-dependent Ca(2+) membrane permeability. It was concluded that cGMP-independent mechanisms of the effects of nitro derivative reflect the peculiarities of excitation-contraction coupling in smooth muscles.

[The effect of sodium nitroprusside on the membrane potential and mechanical tension of the smooth-muscle cells in the rat aorta]

The rat aorta smooth muscles were contracted and depolarised with high potassium or phenylephrin solution which was followed by a relaxation and repolarisation after sodium nitroprusside administration. The latter effect was decreased az a combined action of phenylephrin and high potassium solution. Nitroprusside seems to act through a cGMP-dependent potassium transient activation of the smooth muscle cell membrane.

[The effect of hypothermic stress on Na,K-ATPase activity in rat erythrocytes]

After 3-hr cooling stress, the activity of the erythrocytes' Na,K-ATPase was decreased by 28.9 per cent in rats, its complete restoration occurring within 24 hours after the stress. Possible reasons and factors inducing a disorder in the enzyme activity under conditions of hypothermia, are discussed.

[The age-related characteristics of changes in osmotic and ionic homeostasis in spontaneously hypertensive rats]

The 3-month old SHR differ from the WKY rats in that the former have an increased osmolality, concentration of albumins, activity (but not the concentration) of sodium and a reduced activity of potassium. The shifts in the albumins concentration occur, mainly, on account of the amino acid phenylalanine. The gradient increase of the sodium and potassium concentration between the plasma and muscular tissue in followed by a slight hyperpolarisation of the muscle fibers, a drop in the lability and a increase in pO2. The above shifts of homeostatic parameters were not revealed in the SHR and WKY rats of 1.5 and 6.0 months of age.

Glycosides during ensiling

The content of glycosinolates in crucifers and other plants and their behavior during ensiling was studied. It was found that up to 80% of glycosinolates decompose during ensiling. Acidification of the mass with formic acid somewhat slows down the decomposition of glycosinolates. Decomposition of glycosinolates does not occur during ensiling of clover, which, in the authors' opinion, is explained by the low activity of glycosinolate hydrolases. The evolution of hydrogen sulfide at the start of ensiling of a number of crops was established.

Ultrastructure of the larval corpus allatum of hyphantria cunea Drury (Insecta, Lepidoptera)

The corpora allata of the three last larval instars were studied in newly molted animals, at the beginning, middle, and end of the feeding period, and during the molt period. They were found to consist of uniform gland cells, whose ultrastructure changes in the course of the instars. In glands cells considered to be resting, the outer and inner nuclear membranes run in parallel without forming a dilated perinuclear space. Mitochondria are small, polymorphic, with an electron-dense matrix. The smooth endoplasmic reticulum (SER) appears as stacks of parallel cisternae near the nuclear envelope and in the rest of the cytoplasm, and as accumulations of twisted profiles. Occasionally, the SER takes the form of paracrystalline bodies. There are few small smooth-surfaced vesicles in the cytoplasm. In cells considered as active, a dilated perinuclear space occurs. The peripheral ends of profiles forming the SER are swollen, and numerous vesicles and vacuoles bud off from them to fill the cytoplasm. Mitochondria are large, with a more transparent matrix. The plasma membrane of gland cells located just beneath the connective tissue sheath forms numerous small invaginations. The corpora allata consist of resting cells during the molt periods. At the beginning of each instar, few active gland cells appear. In the middle of the second to last and the third to last instars, the bulk of the gland cells is active. At the end of these instars, there are both active and inactive cells. In the middle of the last instar, the gland cells are inactive or subactive, and at its end, all gland cells are completely inactive.