[Psychosis due to idiopathic basal ganglia calcification]. / Psychose door idiopathische calcificatie van de basale ganglia.

Idiopathic basal ganglia calcification is a rare neuropathological syndrome characterised by symmetrical and bilateral calcifications found primarily in the basal ganglia. Psychosis is describedas an acute presentation of idiopathic ganglia calcification. We describe the development of psychosis in a 48-year-old man, initially hospitalised on the neurology ward due to syncope. A ct scan of the brain showed bilateral, symmetrical calcification of the basal ganglia and nucleus dentatus. Laboratory research excluded other pathological disorders. The patient was referred to a psychiatric ward, where the administration of risperidone led to alleviation of his mental state. This case report underlines the importance of an accurate, comprehensive differential diagnosis and the associated significance of neuroimaging.

[Components of fermentation medium regulate bacteriocin synthesis by the recombinant strain Lactococcus lactis subsp. lactis F-116].

The regulation of the synthesis of bacteriocin produced by the recombinant strain Lactococcus lactis subsp. lactis F-116 has been studied. The synthesis is regulated by the components of the fermentation medium, the content of inorganic phosphate (KH2PO4), yeast autolysate (source of amine nitrogen), and changes in carbohydrates and amino acids. The strain was obtained by fusion of protoplasts derived from two related L. lactis subsp. lactis strains, both exhibiting a weak ability to synthesize the bacteriocin nisin. Decreasing the content of KH2PO4 from 2.0 to 1.0 or 0.5% caused bacteriocin production to go down from 4100 to 2800 or 1150 IU/ml, respectively; the base fermentation medium contained 1.0% glucose, 0.2% NaCl, 0.02% MgSO4, and yeast autolysate (an amount corresponding to 35 mg % ammonium nitrogen). The substitution of sucrose for glucose (as the source of carbon) increased the antibiotic activity by 26%, and the addition of isoleucine, by 28.5%. Elevation of the concentration of yeast autolysate in the low-phosphate fermentation medium stimulated both the growth of the lactococci and the synthesis of bacteriocin. Introduction of 1% KH2PO4, yeast autolysate (in an amount corresponding to 70 mg % ammonium nitrogen), 2.0% sucrose, and 0.1% isoleucine increased the bacteriocin-producing activity of the strain by 2.4 times.

Gadolinium effects on gigaseal formation and the adhesive properties of a fungal amoeboid cell, the slime mutant of Neurospora crassa.

Low gadolinium concentrations induce rapid gigaseal formation and cell adhesion to glass and plastic (polystyrene) substrates in the slime mutant of Neurospora crassa. Cellular adhesion is independent of an integrin-mediated mechanism, because pretreatment with the oligopeptide ARG-GLY-ASP-SER (RGDS) did not inhibit it, and there was no spatial correlation between integrin and adhesions. In contrast, concanavalin A and beta-galactosidase both inhibit adhesion, suggesting that adhesion is mediated by sugar moeities at the cell surface. The adhesion sites are motile in the plasma membrane, as shown by the movement of polystyrene microspheres on the cell surface. In addition to an integrin-based adhesive system, which has already been characterized in walled hyphal cells, hyphae have evolved at least two different plasma membrane-based adhesion mechanisms. The relatively non-specific sugar-mediated adhesion caused by gadolinium may be part of the mechanism of gigaseal formation in other cells. In the absence of sugar-mediated adhesion, gadolinium increases the magnitude of the gigaseal in giant unilamellar liposomes composed of phosphatidylcholine, phosphatidylethanolamine, and cholesterol, with or without the negatively charged phosphatidylserine. Thus, gigaseal formation involves at least two different mechanisms.

Blue light modulation of ion transport in the slime mutant of Neurospora crassa.

Blue light is the primary entrainment signal for a number of developmental and morphological processes in the lower eucaryote Neurospora crassa. Blue light regulates photoactivation of carotenoid synthesis, conidiation, phototropism of perithecia and circadian rhythms. Changes in the electrical properties of the plasma membrane are one of the fastest responses to blue light irradiation. To enable patch-clamp studies on light-induced ion channel activity, the wall-less slime mutant was used. Patch-clamp experiments were complemented by non-invasive ion-selective measurements of light-induced ion fluxes of slime cells using the vibrating probe technique. Blue light usually caused a decrease in conductance within 2-5 minutes at both negative and positive voltages, and a negative shift in the reversal potential in whole-cell patch-clamp measurements. Both K+ and Cl- channels contribute to the inward and outward currents, based on the effects of TEA (10 mM) and DIDS (500 microM). However, the negative shift in the reversal potential indicates that under blue light the Cl- conductance becomes dominant in the electrical properties of the slime cells due to a decrease of K+ conductance. The ion-selective probe revealed that blue light induced the following changes in the net ion fluxes within 5 minutes: 1) decrease in H+ influx; 2) increase in K+ efflux; and 3) increase in Cl- influx. Ca2+ flux was unchanged. Therefore, blue light regulates an ensemble of transport processes: H+, Cl-, and K+ transport.

Protection of Escherichia coli cells against extreme turgor by activation of MscS and MscL mechanosensitive channels: identification of genes required for MscS activity.

Mechanosensitive channels are ubiquitous amongst bacterial cells and have been proposed to have major roles in the adaptation to osmotic stress, in particular in the management of transitions from high to low osmolarity environments. Electrophysiological measurements have identified multiple channels in Escherichia coli cells. One gene, mscL, encoding a large conductance channel has previously been described, but null mutants were without well-defined phenotypes. Here, we report the characterization of a new gene family required for MscS function, YggB and KefA, which has enabled a rigorous test of the role of the channels. The channel determined by KefA does not appear to have a major role in managing the transition from high to low osmolarity. In contrast, analysis of mutants of E.coli lacking YggB and MscL shows that mechanosensitive channels are designed to open at a pressure change just below that which would cause cell disruption leading to death.

Interrelationships between cytoplasmic Ca2+ peaks, pollen hydration and plasma membrane conductances during compatible and incompatible pollinations of Brassica napus papillae.

We have investigated Ca(2+)-involving cell signaling, plasma membrane potentials and conductances and callose formation during early stages of pollination of papillae of Brassica napus. Using fluorescence imaging of calcium green-1, we found that application of a range of pollen types and controls all rapidly produced small localized peaks in papillar cytoplasmic [Ca2+]. This response was more frequent in compatible than incompatible interactions and was correlated with subsequent hydration of the applied pollen grains, indicating that it may be a differential prerequisite of the compatible signaling pathway leading to successful pollinations. In contrast, a slight trend to increased plasma membrane conductance (but with no indications of action potential-like responses) and also callose deposition in papillae adjacent to pollen grains followed pollination in both SC and SI interactions, indicating that alterations in plasma membrane permeability and callose deposition during early phases of pollination are not primary determinants of the fate of attempted pollinations.

The roles of Ca2+ and plasma membrane ion channels in hyphal tip growth of Neurospora crassa.

Growing hyphae of the ascomycete fungus Neurospora crassa contained a tip-high gradient of cytoplasmic Ca2+, which was absent in non-growing hyphae and was insensitive to Gd3+ in the medium. Patch clamp recordings in the cell-attached mode, from the plasma membrane of these hyphae, showed two types of channel activities; spontaneous and stretch activated. The spontaneous channels were identified as inward K+ channels based on inhibition by tetraethylammonium. The stretch activated channels had increased amplitudes in response to elevated Ca2+ in the pipette solution, and thus are permeable to Ca2+ and mediate inward Ca2+ movement. Gd3+, which is an inhibitor of some stretch activated channels, incompletely inhibited stretch activated channel activity. Both tetraethylammonium and Gd3+ only transiently reduced the rates of tip growth without changing tip morphology, thus indicating that the channels are not absolutely essential for tip growth. Furthermore, in contrast to the hyphae of another tip growing organism, Saprolegnia ferax, tip-high gradients of neither spontaneous nor stretch activated channels were found. Voltage clamping of the apical plasma membrane potential in the range from -300 to +150 mV did not affect the rates of hyphal elongation. Collectively, these data suggest that ion transport across the plasma membrane at the growing tip in Neurospora is not obligatory for the maintenance of tip growth, but that a gradient of Ca2+, possibly generated from internal stores in an unknown way, is required.

Cytoskeletal regulation of ion channel distribution in the tip-growing organism Saprolegnia ferax.

Growing hyphal tips of the oomycete Saprolegnia ferax possess a tip-high gradient of stretch-activated ion channels permeable to calcium. These mechanosensitive channels appear to play a direct role in the polarized tip growth process. Treatment of S. ferax hyphae with cytochalasin E leads to the disruption of plasmalemma-associated, peripheral cytoplasmic actin populations and altered morphology of apical protoplasts, and eliminates the tip-high gradient of stretch-activated channels. Cytochalasin E did not alter the normal aggregation of stretch-activated channels. The density of spontaneous K+ channels was decreased in all regions of the hyphae after treatment with cytochalasin E. These results suggest that the peripheral F-actin network in the growing tip of S. ferax hyphae establishes or maintains the tip-high gradient of SA channels, either by the delivery of channel-bearing vesicles to the apex or by the interactions between the channels and the peripheral actin network.

[Postradiation recovery of hemopoietic and stromal precursor cells in mice preinjected with prodigiozan]. / Postradiatsionnoe vosstanovlenie gemopoéticheskikh i stromal'nykh kletok-predshestvennikov u myshei v usloviiakh predvaritel'nogo vvedeniia prodigiozana.

Injection of prodigiozan to mice 24 h before irradiation caused, by the time of the radiation effect, a decrease in the number of haemopoietic cells-precursors (CFUs and CFU-HM) in the bone marrow and an increase in the functional activity of stromal cell-precursors--the haemopoietic microenvironment of transfer units (HMTU); in the spleen, the number of CFUs decreased, but the number of CFU-HM increased considerably. During the postirradiation period, the haemopoietic and stromal precursors were damaged to a lesser extent, and CFUs, CFU-HM and HMTU recovered more readily in prodigiozan-protected animals than in unprotected mice; the HMTU restoration preceded the increase in CFUs and CFU-HM levels.

[Monomerization of the fragment D dimer of stabilized fibrin by a secretion from the medicinal leech salivary gland]. / Monomerizatsiia dimera fragmenta D stabilizirovannogo fibrina sekretom sliunnykh zhelez meditsinskoi piiavki.

The salivary gland secretion of the medicinal leech catalyzes the conversion into monomeric form of the fragment D dimer, the product of limited proteolysis of stabilized fibrin. Analysis of N-terminal sequences revealed identical fragments for the D-dimer gamma-gamma-chains and the D-monomer gamma-chains formed via this reaction and established the presence of only one N-terminal amino acid (Ser). These results provide evidence for the preservation of integrity of the polypeptide chains during monomerization of the D-dimer.

Na(+)-K(+)-ATPase isoforms in different areas of calf brain.

The isoform composition and type of Na(+)-K+ ATPase functional complexes in a number of calf brain membranes were determined. Functionally active enzymes were obtained from microsomes from calf cerebral cortex grey matter, brain stem, and stem axolemma by two different methods involving (1) the selective removal of contaminating proteins according to Jorgensen (1974) and (2) the selective solubilization of the enzyme with subsequent reformation of the membrane structure according to Esmann (1988). The protein components of the isolated preparations were separated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate, transferred to an immobilon membrane [poly(vinylidene difluoride) membrane] by electroblotting, and subjected to structural analysis. The N-terminal amino acid sequences of the alpha- and beta-subunits (alpha 1, alpha 2, alpha 3, beta 1, beta 2) and the isoform composition and type of alpha n beta m functional complexes present in the different microsome preparations were determined. Brain grey matter Na(+)-K+ ATPase was characterized by biphasic kinetics with respect to ouabain inhibition (Ki approximately 10(-6) M and -1.5 x 10(-8) M) and comprised a set of isozymes with subunit compositions of alpha 1 beta 1, alpha 2 beta m, and alpha 3 beta m (where m = 1 and/or 2), with the alpha 1 beta 1 form clearly predominating. Na(+)-K+ ATPase from brain stem and axolemma consisted mainly of a mixture of the isozymes alpha 2 beta 1 and alpha 3 beta 1, which had identical ouabain inhibition constants (Ki approximately 10(-7) M), but in the axolemma there was a large quantity of the alpha 3 beta 1 isozyme. The catalytic subunit alpha 3 within the untreated enzyme complex had increased sensitivity towards endogenous proteolysis. It was therefore possible to isolate enzyme containing the alpha 3 catalytic subunit only in the presence of the protease inhibitor diisopropyl fluorophosphate (DIPF). In the absence of this inhibitor there was a specific fragmentation of the polypeptide chain, resulting in the formation of an extremely stable N-terminal fragment of molecular mass 55 kDa.

[Study of the structure of the photosynthetic reaction center of the green thermophilic bacteria Chloroflexus aurantiacus]. / Izuchenie structury fotosinteticheskogo reaktsionnogo tsentra zelenoi termofil'noi bakterii Chloroflexus aurantlacus.

Analysis of the Chloroflexus aurantiacus reaction centre (RC) using both protein and recombinant DNA techniques resulted in determination of its polypeptide composition and the primary structures of its two subunits. A model of the polypeptide chains' folding in the membrane is suggested based on: i) homology between L- and M-subunits of Chloroflexus aurantiacus RC and their counterparts in purple bacteria; ii) comparison of their hydropathy plots, and iii) data on the tertiary structures of purple bacteria RCs. The role of a number of functionally important amino acid residues in the RC electron transport activity is discussed. Limited proteolysis of the RC under non-denaturing conditions was used to determine the contribution of the N-terminal regions to its thermal stability.

[Primary structure of the basic nuclear protein from spermatozoa of the mollusk Illex argentinus and its comparison with the structure of sperm proteins in other animals]. / Pervichnaia struktura osnovnogo iadernogo belka iz spermatozoidov golovonogogo molliuska Illex argentinus i sravnenie ee so strukturami spermal'nykh belkov drugikh zhivotnykh.

The spermatic protein of chromatin I2 of squid Illex argentinus was separated by HPLC into two components I2-1 and I2-2. Amino acid sequences of the major portion of protein I2-1 (52 residues) and the N-terminal sequence of protein I2-2 (21 residues) were determined. Arginines in protein I2-1 are arranged in clusters typical of protamines; the first cluster is in the N-terminus, the longest heterogeneous basic cluster is in the central part of the protein chain, the C-terminal part of the molecule contains two clusters of three hydroxyamino acids each. The N-terminal sequences of illexins I2-1 and I2-2 (1-14 residues) are highly homologous. Homologous regions were found in illexin I2-1, tunnin of tuna fish and avian gallin thus defining the notion of proteins of an intermediate type from mollusc spermatozoa chromatin exemplified by the squid protamine-like protein.

[Characteristics of the structure of the palatine suture and interalveolar septum in normal children and in diastema]. / Osobennosti stroeniia nebnogo shva i mezhal'veoliarnoi peregorodki u detei v norme i pri diasteme.

The palatine suture is wider in 6-14-year-old children with diastema than in normal ones; this suture is commonly direct and rarely tortuous. This may be due to its inadequate ossification. The width of the diastema does not depend on the suture width. An acuminate interalveolar septum predominates in normal children, but diastema and the child's age are conducive to its flattening. Orthodontic treatment normalizes the width of the palatine suture and the shape of the interalveolar septum, but in many patients the results are not stable.

Immunoaffinity isolation of Na,K-ATPase alpha 3 isoform from pig kidney.

The Na,K-ATPase alpha 3 isoform of the catalytic subunit has been isolated from pig kidney microsomes. The procedure employs immunoaffinity chromatography on Sepharose 4B covalently coupled with monospecific antibodies a-II against the synthetic peptide including the putative alpha 3 N-terminus. The structural analysis provides unambiguous proof that the isolated protein corresponds to the third transcript for the alpha 3 isoform. The N-terminal amino acid sequence determined. Met-Gly-Asp-Lys-Lys-Asp-Asp, shows that unlike the alpha 1 and alpha 2 proteins, the mature Na,K-ATPase isoform lacks post-translational proteolytic processing.

[Amino acid sequence of various peptides of tryptophanyl-tRNA-synthetase from bovine pancreas]. / Aminokislotnaia posledovatel'nost' nekotorykh peptidov triptofanil- tRNK-sintetazy iz podzheludochnoi zhelezy krupnogo rogatogo skota.

Method of isolation of the bovine pancreas tryptophanyl-tRNA synthetase is improved and a protein with greater than or equal to 99% purity, according to PAGE-SDS, is obtained. The pure enzyme is digested with clostripain and the hydrolysate is separated by FPLC anion-exchange chromatography followed by reversed phase HPLC. Amino acid sequences of 6 individual peptides, including C-terminal one, were determined by the automated Edman degradation. A peptide is also revealed which is encoded with the low degeneracy.

[Use of electroblotting as a method for preparing samples of proteins and their fragments for microsequencing]. / Primenenie élektroblottinga v kachestve metoda polucheniia obraztsov belkov i ikh fragmentov dliia mikrosekvenirovaniia.

Gel electrophoresis in the presence of sodium dodecyl sulphate followed by electroblotting was employed in sample preparation for microsequencing proteins and protein fragments. Three types of solid supports were compared: glass fiber filters modified by aminopropyltriethoxysilane or covered with polybrene, and polyvinylidenedifluoride membranes. N-Terminal amino acid sequences of several proteins (Mr 14-140 kDA were determined on a gas-phase sequencer with the standard programme; 20-200 pmoles of the protein can be assayed by this method.