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71.
V Perić Mataruga M Vlahović B Janać L Ilijin M Janković Tomanić D Matić M Mrdaković 《Peptides》2012,37(1):55-62
Ghrelin is a 28-amino acid peptide that has significant effects on appetite and growth in humans and animals. The aim of this study was to examine 4th instar larvae of the pest insect Lymantria dispar L. after ghrelin treatment. Parameters included changes in nutritional indices (efficiency of conversion of ingested food, efficiency of conversion of digested food, approximate digestibility); midgut and fat body mass; total proteases, trypsin and leucine aminopeptidase activities in the midgut; number, height and width of columnar and goblet cells and their nuclei in the midgut epithelium and detection of ghrelin-like immunoreactivity in the midgut tissue. Four subpicomolar injections of ghrelin (0.3pmol) or physiological saline (control) were applied every 24h. The nutritional indices were higher in the ghrelin treated than in the control group. Ghrelin treatment was also associated with elevation of midgut mass, induced digestive enzyme activities, increased fat body mass and morphometric changes in columnar and goblet cells. This is the first report of the presence of ghrelin-like hormone in endocrine cells of an insect midgut. Such information provides additional evidence for application of this relatively simple model system in the future studies of the mechanisms underlying of digestion and energy balance in more complex organisms. 相似文献
72.
Pletikapić G Žutić V Vinković Vrček I Svetličić V 《Journal of molecular recognition : JMR》2012,25(5):309-317
This study highlights the capacity of atomic force microscopy (AFM) for investigating nanoparticle (NP) algal cell interaction with a subnanometer resolution. We designed a set of AFM experiments to characterize NP size, shape, and structure to visualize changes in the cell morphology induced by NPs and to characterize NP interaction with the extracellular polymeric substance (EPS). Samples for AFM imaging were prepared using the same protocol-drop deposition on mica and imaged in air. Here we address the interactions of Ag NPs with ubiquitous, lightly silicified marine diatoms Cylindrotheca fusiformis and Cylindrotheca closterium and their EPS. In natural seawater used throughout this study, the single Ag NPs adopted truncated tetrahedron morphology with particle heights of 10, 20, 30, and 40 nm. This size class Ag NPs penetrates the cell wall through the valve region built of silica NPs embedded in organic matrix. The Ag NPs cause a local damage inside the cell without disintegration of the cell wall. The EPS production has been shown to increase as a feedback response to Ag NP exposure and may contribute to detoxification mechanisms. Imaging EPS at high resolution revealed the incorporation of Ag NPs and their aggregates into the EPS-gel matrix, proving their detoxifying capacity. 相似文献
73.
J Mrvčić D Stanzer E Solić V Stehlik-Tomas 《World journal of microbiology & biotechnology》2012,28(9):2771-2782
Certain species of lactic acid bacteria (LAB), as well as other microorganisms, can bind metal ions to their cells surface or transport and store them inside the cell. Due to this fact, over the past few years interactions of metal ions with LAB have been intensively investigated in order to develop the usage of these bacteria in new biotechnology processes in addition to their health and probiotic aspects. Preliminary studies in model aqueous solutions yielded LAB with high absorption potential for toxic and essential metal ions, which can be used for improving food safety and quality. This paper provides an overview of results obtained by LAB application in toxic metal ions removing from drinking water, food and human body, as well as production of functional foods and nutraceutics. The biosorption abilities of LAB towards metal ions are emphasized. The binding mechanisms, as well as the parameters influencing the passive and active uptake are analyzed. 相似文献
74.
Vesna Djikanovic Momir Paunovic Vera Nikolic Predrag Simonovic Predrag Cakic 《Reviews in Fish Biology and Fisheries》2012,22(1):297-324
As a result of freshwater fish parasitofauna investigations, throughout the past 75 years, the number of parasitic species
is presented. This paper reviews the history, current state, and tendencies of the fish parasitofauna studies in Serbian open
waters. Up to now, in total 170 parasitic species have been reported. Systematic parasitofauna investigations have been carried
out on 54 freshwater fish species in waters of the Danube River Basin in Serbia, also in hill-mountanious watercourses, lakes
and salmonid fishpond of Sjenicko-Pesterska plateau (south-west region of Serbia), Homolje area (east Serbia), and in Vlasina
lake (south-east Serbia). This data review pointed that it is necessary to continue the investigation on fish parasites in
Serbia. The data on freshwater fish parasites are important for evaluation of general influence on the community structure. 相似文献
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76.
Dragana Petrovic-Kosanovic Maja Cakic Milosevic Mirela Budec Vesna Koko 《Central European Journal of Biology》2012,7(4):603-610
Isolated rat adrenal medulla was analyzed by light and electron microscope after an acute (60 min) exposure to high ambient temperature (38°C). Under these conditions there was a significant rise in plasma adrenaline and noradrenaline. Stereological investigation by light microscopy showed a significant decrease in volume density of cells and an increase in the interstitium. At the ultrastructural level, the profile area of cells, nuclei and cytoplasm of adrenaline cells were significantly decreased. After the heat stress numbers of resting granules in adre naline and noradrenaline cells were significantly reduced, while the numbers of altered granules and empty containers in both types of adrenomedullar cells were significantly increased. 相似文献
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Marina Pehli? Dina Vrki? Veselin ?krabi? Ana Jeron?i? Gordana Stipan?i? Anita ?pehar Uroji? Igor Marjanac Jasminka Jak?i? Zrinka Ka?i? Vesna Boraska Tatijana Zemunik 《PloS one》2012,7(11)