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61.
62.
Amrita Roy Choudhury Emilia Sikorska Johannes van den Boom Peter Bayer ?ukasz Popenda Kosma Szutkowski Stefan Jurga Massimiliano Bonomi Andrej Sali Igor Zhukov Sabina Passamonti Marjana Novi? 《PloS one》2015,10(8)
We present a 3D model of the four transmembrane (TM) helical regions of bilitranslocase (BTL), a structurally uncharacterized protein that transports organic anions across the cell membrane. The model was computed by considering helix-helix interactions as primary constraints, using Monte Carlo simulations. The interactions between the TM2 and TM3 segments have been confirmed by Förster resonance energy transfer (FRET) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy, increasing our confidence in the model. Several insights into the BTL transport mechanism were obtained by analyzing the model. For example, the observed cis-trans Leu-Pro peptide bond isomerization in the TM3 fragment may indicate a key conformational change during anion transport by BTL. Our structural model of BTL may facilitate further studies, including drug discovery. 相似文献
63.
Lidia Sonakowska Agnieszka W?odarczyk Izabela Poprawa Marcin Binkowski Joanna ?róbka Karolina Kamińska Michalina Kszuk-Jendrysik ?ukasz Chajec Bart?omiej Zajusz Magdalena Maria Rost-Roszkowska 《PloS one》2015,10(5)
The freshwater shrimp Neocaridina heteropoda (Crustacea, Malacostraca, Decapoda) originates from Asia and is one of the species that is widely available all over the world because it is the most popular shrimp that is bred in aquaria. The structure and the ultrastructure of the midgut have been described using X-ray microtomography, transmission electron microscopy, light and fluorescence microscopes. The endodermal region of the alimentary system in N. heteropoda consists of an intestine and a hepatopancreas. No differences were observed in the structure and ultrastructure of males and females of the shrimp that were examined. The intestine is a tube-shaped organ and the hepatopancreas is composed of two large diverticles that are divided into the blind-end tubules. Hepatopancreatic tubules have three distinct zones – proximal, medial and distal. Among the epithelial cells of the intestine, two types of cells were distinguished – D and E-cells, while three types of cells were observed in the epithelium of the hepatopancreas – F, B and E-cells. Our studies showed that the regionalization in the activity of cells occurs along the length of the hepatopancreatic tubules. The role and ultrastructure of all types of epithelial cells are discussed, with the special emphasis on the function of the E-cells, which are the midgut regenerative cells. Additionally, we present the first report on the existence of an intercellular junction that is connected with the E-cells of Crustacea. 相似文献
64.
Dennis S. Nielsen Łukasz Krych Karsten Buschard Camilla H.F. Hansen Axel K. Hansen 《FEBS letters》2014
Type 1 diabetes (T1D) is an autoimmune disease ultimately leading to destruction of insulin secreting β-cells in the pancreas. Genetic susceptibility plays an important role in T1D etiology, but even mono-zygotic twins only have a concordance rate of around 50%, underlining that other factors than purely genetic are involved in disease development. Here we review the influence of dietary and environmental factors on T1D development in humans as well as animal models. Even though data are still inconclusive, there are strong indications that gut microbiota dysbiosis plays an important role in T1D development and evidence from animal models suggests that gut microbiota manipulation might prove valuable in future prevention of T1D in genetically susceptible individuals. 相似文献
65.
Kasprzak A Malkowski W Helak-Łapaj C Seraszek A Kaczmarek E Adamek A Zabel M 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2010,48(4):646-657
The study aimed at examination of tissue expression of polysaccharides and secretory mucin 5AC (MUC5AC) in young patients (up to 25 years of age) with a symptomatic gallstones. For comparison, patients most frequently subjected to cholecystectomy were studied, i.e. patients of approximately 50 years of age with the same diagnosis. In quantitative studies on tissue expression of both mucus components, the modern technique of spatial visualization was applied for the first time. Application of the technique permitted to demonstrate significant positive relationships between expression of glycoproteins (immunocytochemical ABC technique for detection of MUC5AC) and expression of sugar components in mucus (PAS technique) and to confirm suitability of the technique for quantitative appraisal of both histochemical and immunocytochemical reactions. An even higher expression of polysaccharides in the entire mucosa and of MUC5AC was detected in gallbladder epithelium of 50-year-old patients, as compared to young patients with symptomatic gallstones. In the young patients, expression of polysaccharides correlated with inflammatory activity (grading), width of gallbladder wall and PLT level in peripheral blood. A significantly higher expression of polysaccharides in gallbladder epithelium was demonstrated in young patients admitted in the emergency mode to the hospital. These correlations in young patients may suggest a role of both mucus components in pathogenesis of cholelithiasis in this age group. A quantitative appraisal of mucus component expression in the two parts of gallbladder mucosa (epithelium vs. entire mucosa) using spatial visualization technique permitted to more accurately compare production of glycoproteins and of polysaccharides in patients with cholelithiasis and to demonstrate additional correlations of a potential clinical significance. 相似文献
66.
Mariola Kuczer Katarzyna Dziubasik Anna Midak‐Siewirska Renata Zahorska Mirosław Łuczak Danuta Konopińska 《Journal of peptide science》2010,16(4):186-189
The subject of these studies was synthesis and determination of biological properties of a series of insect peptides, such as alloferon, Any‐GS and their analogues. The synthesis of 14 peptides was performed by the solid‐phase method. Biological effect of these peptides was evaluated by the antiviral test against Human Herpes Virus type 1 (HHV‐1) in vitro using a Vero cell line. It was found that the investigated peptides inhibit the replication of HHV‐1 in Vero cells. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
67.
Robert Rutkowski Łukasz Rejt Anna Tereba Alicja Gryczyńska-Siemiątkowska Bartosz Janic 《European Journal of Wildlife Research》2010,56(3):297-305
We analysed the genetic structure of the European kestrel population of Central Poland using nine highly polymorphic microsatellite loci. Samples were collected in two urban locations (Warsaw and ?ód?) and two rural areas. Sampling locations were at nearly equal distances from each other along an east to west line. We performed genotyping in a total of 99 birds. The results revealed the presence of a genetic structure in the population investigated. Bayesian clustering indicated that samples originated from more than one population. Genetic differentiation was less pronounced among the birds nesting in Warsaw and in the two rural sites, whereas all pairwise comparisons with the ?ód? population indicated moderate and significant genetic differentiation. The observed pattern of differentiation might have been caused by two factors: changes in allele frequency between seasons and/or the founding of the urban population of ?ód? from a different source population than the urban population from Warsaw. Additionally, we found a rather high gene flow among kestrels from the Warsaw urban area and the two investigated rural areas. 相似文献
68.
Mariusz Lamentowicz Łukasz Lamentowicz Willem O. van der Knaap Maciej Gąbka Edward A. D. Mitchell 《Microbial ecology》2010,59(3):499-510
We studied the vegetation, testate amoebae and abiotic variables (depth of the water table, pH, electrical conductivity, Ca
and Mg concentrations of water extracted from mosses) along the bog to extremely rich fen gradient in sub-alpine peatlands
of the Upper Engadine (Swiss Alps). Testate amoeba diversity was correlated to that of mosses but not of vascular plants.
Diversity peaked in rich fen for testate amoebae and in extremely rich fen for mosses, while for testate amoebae and mosses
it was lowest in bog but for vascular plants in extremely rich fen. Multiple factor and redundancy analyses (RDA) revealed
a stronger correlation of testate amoebae than of vegetation to water table and hydrochemical variables and relatively strong
correlation between testate amoeba and moss community data. In RDA, hydrochemical variables explained a higher proportion
of the testate amoeba and moss data than water table depth. Abiotic variables explained a higher percentage of the species
data for testate amoebae (30.3% or 19.5% for binary data) than for mosses (13.4%) and vascular plants (10%). These results
show that (1) vascular plant, moss and testate amoeba communities respond differently to ecological gradients in peatlands
and (2) testate amoebae are more strongly related than vascular plants to the abiotic factors at the mire surface. These differences
are related to vertical trophic gradients and associated niche differentiation. 相似文献
69.
Joanna Łaźniewska Violetta K. Macioszek Christopher B. Lawrence Andrzej K. Kononowicz 《Acta Physiologiae Plantarum》2010,32(1):1-10
Necrotrophic fungi, being the largest class of fungal plant pathogens, pose a serious economic problem to crop production. They are the cause of heavy losses in agriculture worldwide. Understanding the process of plant infection by necrotrophic fungi, including subtle interaction networks connecting such evolutionarily distinct organisms has recently been given high research priority. Such studies are now possible mainly because of the utility of the model plant Arabidopsis thaliana. A. thaliana has a sequenced genome and thousands of mutants available, allowing investigation of virtually all aspects of plant pathogenesis. This review focuses on morphological and molecular changes in A. thaliana, which occur during response to infection by necrotrophic fungi. These responses in relation to resistance and susceptibility of the plant will be discussed. 相似文献
70.
Łukasz J Łuczaj 《Journal of ethnobiology and ethnomedicine》2010,6(1):1-16
In Italy, malaria was an endemic disease that was eradicated by the mid-20th century. This paper evaluates the prophylactic and therapeutic remedies used by folk medicine to cure malaria in Calabria (southern Italy). The data has been collected by analysing works of physicians, ethnographers, folklorists and specialists of the study of Calabrian history between the end of the 19th century and the 20th century. The data collected have allowed us to describe the most common cures used by the Calabrian people to treat malaria and the most evident symptoms of this disease, such as intermittent fever, hepato-spleenomegaly, asthenia and dropsy. This approach uncovered a heterogeneous corpus of empirical, magical and religious remedies, which the authors have investigated as evidences of past "expert medicine" and to verify their real effectiveness in the treatment of malaria. 相似文献