Localization of biogenic monoamines in the dura mater of the rat brain

Quantitative and qualitative composition of catecholamines (noradrenaline and dophamine) and indolalkylamines (serotonin and tryptamine) and their localization have been studied in cells and neural fibers of the rat dura mater. Luminiscent-cytophotometric and electron microscopic methods have revealed two types of cells depositing biogenic monoamines. As demonstrate the experiments with rausedil injection, monoaminocytes of the first type (mast cells) contain predominantly indolalkylamines and a small amount of dophamine. Monoaminocytes of the second type (chromaffin cells) synthesize mainly serotonin and, perhaps, tryptamine. In adrenergic neural fibers only noradrenaline has been found to be present.     

Enhancement of nickel and lead accumulation and their toxic growth-inhibitory effects on amaranth seedlings in the presence of calcium

The effects of Ni(NO₃)₂ and Pb(NO₃)₂ on Amaranthus sp. L. root growth and the effect of calcium on heavy metal (HM) accumulation in the growing root zone and root growth inhibition were studied. The seeds were germinated in the Pb(NO₃)₂ solutions at concentrations of 50, 100, 200, 500 and 700 μM or Ni(NO₃)₂ solutions at concentrations of 10, 50, 70, 100, and 500 μM in the presence of 100 μM Ca(NO₃)₂ or without it. HM toxicity was assesses in 7 days after seed sowing by the root length. Distribution of HM over the tissues of the growing root part was examined histochemically. Ni was more toxic to root growth than Pb. In the presence of Ca, Ni and Pb accumulation in the amaranth root growing part increased markedly, and this enhanced their growth-inhibitory of action. A comparison of results obtained in this work and available from the literature permitted a conclusion that the routes of HM penetration into the root differ in different plant species, and this determines ambiguity of protective Ca action.     

<Emphasis Type="Italic">α</Emphasis>-Amylase inhibitor-1 gene from <Emphasis Type="Italic">Phaseolus vulgaris</Emphasis> expressed in <Emphasis Type="Italic">Coffea arabica</Emphasis>plants inhibits α-amylases from the coffee berry borer pest

Background  

Coffee is an important crop and is crucial to the economy of many developing countries, generating around US70 billion per year. There are 115 species in the < i > Coffea < /i > genus, but only two, < i > C. arabica < /i > and < i > C. canephora < /i > , are commercially cultivated. Coffee plants are attacked by many pathogens and insect-pests, which affect not only the production of coffee but also its grain quality, reducing the commercial value of the product. The main insect-pest, the coffee berry borer ( < i > Hypotheneumus hampei < /i > ), is responsible for worldwide annual losses of around US70 billion per year. There are 115 species in the Coffea genus, but only two, C. arabica and C. canephora, are commercially cultivated. Coffee plants are attacked by many pathogens and insect-pests, which affect not only the production of coffee but also its grain quality, reducing the commercial value of the product. The main insect-pest, the coffee berry borer (Hypotheneumus hampei), is responsible for worldwide annual losses of around US500 million. The coffee berry borer exclusively damages the coffee berries, and it is mainly controlled by organochlorine insecticides that are both toxic and carcinogenic. Unfortunately, natural resistance in the genus Coffea to H. hampei has not been documented. To overcome these problems, biotechnological strategies can be used to introduce an α-amylase inhibitor gene (α-AI1), which confers resistance against the coffee berry borer insect-pest, into C. arabica plants.     

Dynamic rearrangement of the filamentous actin network occurs during zoosporogenesis and encystment in the oomycete phytophthora cinnamomi

The organization of filamentous actin (F-actin) in living cells of the oomycete Phytophthora cinnamomi was determined during zoosporogenesis and zoospore encystment by microinjecting sporangia with fluorescently labeled phalloidin and observing resultant fluorescence by confocal microscopy. In multinucleate sporangia prior to the induction of cleavage, phalloidin labeling took the form of plaques which occurred mainly in the periphery of the sporangia. After induction of cleavage, phalloidin labeling showed that the plaques disappeared and that F-actin began to accumulate along the developing cleavage planes and around nuclei and water expulsion vacuoles. F-actin labeling was also observed near the plasma membrane in zoospores and young cysts but reverted to the plaque form in older cysts. Localization of F-actin close to the developing cleavage planes is consistent with the idea that actin microfilaments function in the positioning and expansion of the cleavage membranes. Observations of plaques of actin in living sporangia provide evidence that plaques are not aldehyde-induced fixation artifacts. Copyright 1998 Academic Press.     

Serglycin expression during monocytic differentiation of U937-1 cells

Serglycin is the major proteoglycan in most hematopoietic cells, including monocytes and macrophages. The monoblastic cell line U937-1 was used to study the expression of serglycin during proliferation and differentiation. In unstimulated proliferating U937-1 cells serglycin mRNA is nonconstitutively expressed. The level of serglycin mRNA was found to correlate with the synthesis of chondroitin sulfate proteoglycan (CSPG). The U937-1 cells were induced to differentiate into different types of macrophage-like cells by exposing the cells to PMA, RA, or VitD3. These inducers of differentiation affected the expression of serglycin mRNA in three different ways. The initial upregulation seen in the normally proliferating cells was not observed in PMA treated cells. In contrast, RA increased the initial upregulation, giving a reproducible six times increase in serglycin mRNA level from 4 to 24 h of incubation, compared to a four times increase in the control cells. VitD3 had no effect on the expression of serglycin mRNA. The incorporation of (35S)sulfate into CSPG decreased approximately 50% in all three differentiated cell types. Further, the (35S)CSPGs expressed were of larger size in PMA treated cells than controls, but smaller after RA treatment. This was due to the expression of CSPGs, with CS-chains of 25 and 5 kDa in PMA and RA treated cells, respectively, compared to 11 kDa in the controls. VitD3 had no significant effect on the size of CSPG produced. PMA treated cells secreted 75% of the (35S)PGs expressed, but the major portion was retained in cells treated with VitD3 or RA. The differences seen in serglycin mRNA levels, the macromolecular properties of serglycin and in the PG secretion patterns, suggest that serglycin may have different functions in different types of macrophages.      

The correction action of Phosprenyl and Gamavit on the functional activity of mouse peritoneal macrophages in response to high doses of Staphylococcus aureus alpha-toxin

The study of the functional activity of peritoneal macrophages of BALB/c mice at different stages of the toxic action caused by S. aureus alpha-toxin (ST) was carried out. The analysis of the dynamics of toxic reaction revealed the main critical points of triggering necrotic processes: the first hour and day 2. One hour after the injection of large doses of ST a sharp increase in the process of antigen binding with its subsequent sharp decrease. Simultaneously, a decrease in the activity of the lysosomal enzymes cathepsin D and acidic phosphatase was established, which was indicative of the destabilization of both lysosomal and cellular macrophage membranes. The increase of oxygen metabolism on day 2, together with the release of lysosomal proteases into the extracellular area, correlated with the maximum death rate of mice and served as the main index of the development of necrosis. The prophylactic and therapeutic use of the preparations Gamavit and Phosprenyl revealed their antitoxic activity and capacityfor stimulating the level of natural body resistance.     

On the Ability of High Density Lipoproteins to Remove Phospholipid Peroxidation Products from Erythrocyte Membranes

To study the transfer of oxidized phospholipids from cell membranes to high-density lipoproteins (HDL), human Cu²⁺-oxidized erythrocyte membranes were incubated with HDL₃ subfraction for 17 h at 37°C followed by isolation of the supernatant, precipitation from it of HDL₃, and determination of lipid peroxide products (LPP) in them. The incubation increased the content of lipid hydroperoxides in HDL₃ significantly (by 32 and 40% calculated per ml of sample or mg of protein) and of malondialdehyde (by 27 and 34%, respectively) compared to control (incubation of HDL₃ alone). The content of conjugated dienes did not change significantly. Fluorescence analyses of isolated HDL₃ particles showed that the content of fluorescent products (_ex = 365 nm, _em = 430 nm) in them was 2.5 times higher than in control, and the number of binding sites for the 1-anilinonaphthalene-8-sulfonic acid probe decreased by 22%. This also confirms accumulation of LPP in the lipoprotein subfraction. It seems likely that an increase in LPP (at least hydroperoxides) in HDL₃ after their incubation with oxidized membranes occurs via transport of phospholipids containing LPP from erythrocyte membranes to lipoproteins. The data on the ability of HDL₃ to accept LPP from erythrocyte membranes in vitro suggest that HDL₃ may have a protective action on cell membranes undergoing oxidation in vivo as well.     

Localisation of the Vacuolar Proton Pump (V-H+-ATPase) and Carbonic Anhydrase II in the Human Eccrine Sweat Gland

The localisation of the vacuolar proton pump (V-H+ -ATPase) and the enzyme carbonic anhydrase II (CAII) was investigated in the human eccrine sweat gland employing standard immunohistochemical techniques after antigen retrieval using microwave heat treatment and high pressure. The high-pressure antigen retrieval unmasked the presence of V-H+ -ATPase in the clear cells of the secretory coil, with a distribution similar to that previously observed for CAII. However, the dark cells were unreactive to both antibodies. In addition, heat and high-pressure antigen retrieval demonstrated the presence of CAII in the apical zone of luminal cells of the reabsorptive duct, a location not previously reported. The localisation of V-H+ -ATPase and CAII in the secretory coil clear cells suggests that the formation of HCO3- and H+ by carbonic anhydrase II and the transport of H+ by V-H+ -ATPase may play an role in sweat fluid secretion. Their presence at the apex of the duct cells indicates involvement in ductal ion reabsorption.