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131.
132.
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
133.
King JD Mechkarska M Coquet L Leprince J Jouenne T Vaudry H Takada K Conlon JM 《Peptides》2012,33(1):35-43
Peptidomic analysis of norepinephrine-stimulated skin secretions led to the identification of host-defense peptides belonging to the magainin, peptide glycine-leucine-amide (PGLa), and caerulein precursor fragment (CPF) families from the tetraploid frogs, Xenopus petersii (Peters' clawed frog) and Xenopus pygmaeus (Bouchia clawed frog), and the octoploid frog Xenopus lenduensis (Lendu Plateau clawed frog). Xenopsin-precursor fragment (XPF) peptides were not detected. The primary structures of the antimicrobial peptides from X. petersii demonstrate a close, but not conspecific relationship, with Xenopus laevis whereas the X. pygmaeus peptides show appreciable variation from previously characterized orthologs from other Xenopus species. Polyploidization events within the Xenopodinae (Silurana+Xenopus) are associated with extensive gene silencing (nonfunctionization) but unexpectedly the full complement of four PGLa paralogs were isolated from X. lenduendis secretions. Consistent with previous data, the CPF peptides showed the highest growth-inhibitory activity against bacteria with CPF-PG1 (GFGSLLGKALKIGTNLL.NH(2)) from X. pygmaeus combining high antimicrobial potency against Staphylococcus aureus (MIC=6 μM) with relatively low hemolytic activity (LC(50)=145 μM). 相似文献
134.
An improved approach to the evaluation of the rate constants of drugs binding to the open channel underlying the transient outward potassium current I(t0) is described. It is based on an analysis of a quantitative model formulated by a set of twelve differential equations. The rate constants are calculated from the time constants resulting from an approximation of the time course of apparent inactivation of the recorded I(t0) by two exponentials in the absence and by three exponentials in the presence of a blocking agent. The model study confirmed significantly higher accuracy in comparison with the existing electrophysiological method. 相似文献
135.
Alvarez M Huygens D Díaz LM Villanueva CA Heyser W Boeckx P 《Plant, cell & environment》2012,35(1):126-135
Acid phosphatase (ACP) enzymes are involved in the mobilization of soil phosphorus (P) and polyphosphate accumulated in the fungal tissues of ectomycorrhizal roots, thereby influencing the amounts of P that are stored in the fungus and transferred to the host plant. This study evaluated the effects of ectomycorrhizal morphotype and soil fertility on ACP activity in the extraradical mycelium (ACP(myc)), the mantle (ACP(mantle)) and the Hartig net region (ACP(Hartig)) of ectomycorrhizal Nothofagus obliqua seedlings. ACP activity was quantified in vivo using enzyme-labelled fluorescence-97 (ELF-97) substrate, confocal laser microscopy and digital image processing routines. There was a significant effect of ectomycorrhizal morphotype on ACP(myc), ACP(mantle) and ACP(Hartig), while soil fertility had a significant effect on ACP(myc) and ACP(Hartig). The relative contribution of the mantle and the Hartig net region to the ACP activity on the ectomycorrhizal root was significantly affected by ectomycorrhizal morphotype and soil fertility. A positive correlation between ACP(Hartig) and the shoot P concentration was found, providing evidence that ACP activity at the fungus:root interface is involved in P transfer from the fungus to the host. It is concluded that the spatial distribution of ACP in ectomycorrhizas varies as a function of soil fertility and colonizing fungus. 相似文献
136.
Georgieva M Roguev A Balashev K Zlatanova J Miloshev G 《Biochimica et biophysica acta》2012,1819(5):366-374
Despite the existence of certain differences between yeast and higher eukaryotic cells a considerable part of our knowledge on chromatin structure and function has been obtained by experimenting on Saccharomyces cerevisiae. One of the peculiarities of S. cerevisiae cells is the unusual and less abundant linker histone, Hho1p. Sparse is the information about Hho1p involvement in yeast higher-order chromatin organization. In an attempt to search for possible effects of Hho1p on the global organization of chromatin, we have applied Chromatin Comet Assay (ChCA) on HHO1 knock-out yeast cells. The results showed that the mutant cells exhibited highly distorted higher-order chromatin organization. Characteristically, linker histone depleted chromatin generally exhibited longer chromatin loops than the wild-type. According to the Atomic force microscopy data the wild-type chromatin appeared well organized in structures resembling quite a lot the "30-nm" fiber in contrast to HHO1 knock-out yeast. 相似文献
137.
Jimmy?Cabra-GarcíaEmail author Christian?Bermúdez-Rivas Ana?Milena?Osorio Patricia?Chacón 《Biodiversity and Conservation》2012,21(6):1493-1508
In this study α and β diversity patterns of five leaf litter arthropod groups (ants, predatory ants, oribatid mites, spiders
and other arachnids) were described and compared in 39 sampling patches of a transformed landscape in southwestern Colombia,
that represented five vegetation types: secondary forest, riparian forest, giant bamboo forest, pasture and sugarcane crop.
It was also assessed whether some taxa could be used as diversity surrogates. A total of 6,765 individuals grouped in 290
morphospecies were collected. Species richness in all groups was lower in highly transformed vegetation types (pasture, sugarcane
crop) than in native ones (forests). In contrast, there were no clear tendencies of β diversity among vegetation types. Considering
sampling patches, 0.1–42% of the variation in α diversity of one taxonomic group could be explained from the α diversity of
another, and 0.2–33% of the variation of β diversity of a given taxon was explained by that in other groups. Contrary to recent
findings, we concluded that patterns of α diversity are more congruent than patterns of β diversity. This fact could be attributed
to a sampling effect that promotes congruence in α diversity and to a lack of a clear regional ecological gradient that could
promote congruent patterns of β diversity. We did not find evidence for an ideal diversity surrogate although diversity patterns
of predatory ants had the greatest congruencies. These results support earlier multi-taxon evaluations in that conservation
planning should not be based on only one leaf litter arthropod group. 相似文献
138.
Milena Sant Pamela Minicozzi Claudia Allemani Claudia Cirilli Massimo Federico Riccardo Capocaccia Mario Budroni Pina Candela Emanuele Crocetti Fabio Falcini Stefano Ferretti Mario Fusco Adriano Giacomin Francesco La Rosa Lucia Mangone Maurilio Natali Maurizio Ponz De Leon Adele Traina Rosario Tumino Paola Zambon 《Cancer epidemiology》2012,36(6):541-547
BackgroundPopulation-based cancer registry studies of care patterns can help elucidate reasons for the marked geographic variation in cancer survival across Italy. The article provides a snapshot of the care delivered to cancer patients in Italy.MethodsRandom samples of adult patients with skin melanoma, breast, colon and non-small cell lung cancers diagnosed in 2003–2005 were selected from 14 Italian cancer registries. Logistic models estimated odds of receiving standard care (conservative surgery plus radiotherapy for early breast cancer; surgery plus chemotherapy for Dukes C colon cancer; surgery for lung cancer; sentinel node biopsy for >1 mm melanoma, vs. other treatment) in each registry compared to the entire sample (reference).ResultsStage at diagnosis for breast, colon and melanoma was earlier in north/central than southern registries. Odds of receiving standard care were lower than reference in Sassari (0.68, 95%CI 0.51–0.90) and Napoli (0.48, 95%CI 0.35–0.67) for breast cancer; did not differ across registries for Dukes C colon cancer; were higher in Romagna (3.77, 95%CI 1.67–8.50) and lower in Biella (0.38, 95%CI 0.18–0.82) for lung cancer; and were higher in Reggio Emilia (2.37, 95%CI 1.12–5.02) and lower in Ragusa (0.27, 95%CI 0.14–0.54) for melanoma.ConclusionsNotwithstanding limitations due to variations in the availability of clinical information and differences in stage distribution between north/central and southern registries, our study shows that important disparities in cancer care persist across Italy. Thus the public health priority of reducing cancer survival disparities will not be achieved in the immediate future. 相似文献
139.
Casiraghi A Di Grigoli M Cilurzo F Gennari CG Rossoni G Minghetti P 《AAPS PharmSciTech》2012,13(1):247-253
The effect of a homologue series of nonionic surfactants, namely poly(ethylene glycol) (PEG) fatty acid esters, differing
in oxyethylene (PEG 8, PEG 12, and PEG 40) and fatty acid (stearate, mono and di-laurate, and mono and di-oleate) chain lengths,
on in vitro skin permeability of ketoprofen (KTP) vehicled in plasters was investigated. The drug diffusion through hairless mouse skin
as well as the effect of the surfactant type and strength was studied by Franz diffusion cells and ATR-FTIR spectroscopy.
The use of PEG stearate series revealed that the surfactant with the largest polar head, namely PEG 40, was ineffective in
enhancing the skin permeation of KTP, independently of the plaster concentrations. The effect of the hydrophobic chain was
investigated only by using the shortest oxyethylene chains. The experimental results revealed that the oxyethylene chain length
of surfactants appeared to be more influent than the alkyl chain. The prediction of the absorption enhancing capability of
these PEG derivatives appeared related to the vehicle other than the proper combination of the number of ethylene oxide groups
and alkyl groups. 相似文献
140.
Kobets T Havelková H Grekov I Volkova V Vojtíšková J Slapničková M Kurey I Sohrabi Y Svobodová M Demant P Lipoldová M 《PLoS neglected tropical diseases》2012,6(6):e1667