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1.
Interaction between cytotoxin of the Central Asia cobra venom and dimiristoylphosphatidylcholine bilayer depending on its phase state was studied by ESR with spin label. A conclusion can be drawn that the efficiency of cytotoxin effect on the membranes depends on their phase state. Cytotoxin molecules are incorporated into myophile region of the bilayer, only if the latter is in the liquid crystal state. The interaction between cytotoxins and lipids of the bilayer in a gel state is in the main conditioned by electrostatic forces.  相似文献   
2.
Using accumulating preparations of the small intestine mucose, studies have been made of the initial stages of glucose uptake from solutions of glucose, maltose and starch in rat puppies at the age of 17, 24, 31 and 38 days, which were subjected from the 10th to the 17th day of postnatal life to daily heating (up to 40-41 degrees C) or cooling (up to 6-7 degrees C) for 2 hours. It was found that in heat-adapted animals, the rate of accumulation of "free" glucose remained the same as in control animals, whereas the rate of uptake of the glucose in the form of maltose or starch was significantly decreased. Cold adaptation promoted stable stimulation of carbohydrate hydrolysis and transport functions of the intestine.  相似文献   
3.
Probiotics and Antimicrobial Proteins - Peptides are considered very important due to the diversity expressed through their amino acid sequence, structure variation, large spectrum, and their...  相似文献   
4.
International Journal of Peptide Research and Therapeutics - The clinical application of some natural molecules in therapy is usually limited due to the lack of feasible delivery systems....  相似文献   
5.
Testicular cancer is the most common cancer among young men of reproductive age. Bleomycin is a frequently used drug for the treatment of several malignancies and is part of the chemotherapy protocols in testicular cancer. Bleomycin causes an increase in oxidative stress which has been shown to induce apoptosis in cancer cells. Curcumin (diferuloylmethane), an active component of the spice turmeric, has attracted interest because of its anti-inflammatory and chemopreventive activities. However, no study has been carried out so far to elucidate its interaction with bleomycin in testicular cancer cells. In this study, we investigated the effects of curcumin and bleomycin on apoptosis signalling pathways and compared the effects of bleomycin with H2O2 which directly produces reactive oxygen species. We measured apoptosis markers such as caspase-3, caspase-8, and caspase-9 activities and Bcl-2, Bax, and Cyt-c levels in NCCIT cells incubated with curcumin (5 μM), bleomycin (120 μg/ml), bleomycin + curcumin, H2O2 (35 μM), and H2O2 + curcumin for 72 h. Curcumin, bleomycin, and H2O2 caused apoptosis indicated as increases in caspase-3, caspase-8, and caspase-9 activities and Bax and cytoplasmic Cyt-c levels and a decrease in Bcl-2 level. Concurrent use of curcumin with bleomycin decreased caspase activities and Bax and Cyt-c levels compared to their separate effects in NCCIT cells. Our findings suggest that concurrent use of curcumin during chemotherapy in testis cancer should be avoided due to the inhibitory effect of curcumin on bleomycin-induced apoptosis.  相似文献   
6.
A tentative survey on selected marine fish farms was undertaken to delineate the extent to which infections with Staphylococcus species occur in Turkish aquaculture systems. To determine the presence and the distribution of fish pathogenic staphylococci, representative farm types such as marine cages as well as inland pond farms working with saline-ground water and a large hatchery were selected. Field sampling was performed in a total of 13 commercial fish farms that are located in the most-popular aquaculture sites of Turkey. Samples were taken between October 2013 and August 2014. Almost all size classes of the most commonly marine cultured fish species in Turkey were investigated, including Dicentrarchus labrax, Sparus aurata, Argyrosomus regius, Diplodus puntazzo, Dentex dentex, Onchorhynchus mykiss and Salmo labrax. After a visual check, specimens with various clinical signs were sampled for bacteriological and histopathological investigations. Mixed infections of staphylococci along with Vibrio and Aeromonas representatives were detected in Dicentrarchus labrax, Sparus aurata and Diplodus puntazzo samples obtained from 7 farms. The following pathogens were identified: Staphylococcus. epidermidis, S. aureus, S. capitis subsp. capitis, S. lentus, S. hominis subsp. hominis and S. sciuri subsp. sciuri. Main clinical and histopathological effects of the infections in fishes were revealed. The pathogenicity of some isolates was confirmed with in vivo pathogenicity assay and SDS-PAGE analysis.  相似文献   
7.
Abstract

It has been shown by the equilibrium dialysis that at a polyU concentration above the “critical” one, the complete polymer saturation with trivaline reaches approximately 0.7 trivaline molecules per one phosphate group. i.e. at these conditions peptide dimer occupies on polyU a site of three bases (phosphates) in length. The trivaline complex with polyU at a concentration lower than the “critical” one does not reveal any noticeable fluorescence, but has rather significant positive linear dichroism at 265 and 330 nm. The trivaline-nucleic acids complex has a significant fluorescence at any dsDNA concentration while with polyU it is only so at a concentration above the “critical” one. Electron microscopy has shown that at a rather high concentration of dsDNA molecules in solution a “biduplex” structure undergoes an additional stage of compaction, during which the extended particles more than 30 nm in diameter are formed.

Schematic models for the trivaline complexes and compact structures with dsDNA and ssRNA are propose  相似文献   
8.
Antioxidants may prevent apoptosis of cancer cells via inhibiting reactive oxygen species (ROS). However, to date no study has been carried out to elucidate the effects of strong antioxidant N‐acetylcysteine (NAC) on Bleomycin induced apoptosis in human testicular cancer (NTERA‐2, NT2) cells. For this reason, we studied the effects of Bleomycin and NAC alone and in combination on apoptotic signaling pathways in NT2 cell line. We determined the cytotoxic effect of bleomycin on NT2 cells and measured apoptosis markers such as Caspase‐3, ‐8, ‐9 activities and Bcl‐2, Bax, Cyt‐c, Annexin V‐FTIC and PI levels in NT2 cells incubated with different agents for 24 h. Early apoptosis was determined using FACS assay. We found half of the lethal dose (LD50) of Bleomycin on NT2 cell viability as 400, 100, and 20 µg/ml after incubations for 24, 48, and 72 h, respectively. Incubation with bleomycin (LD50) and H2O2 for 24 h increased Caspase‐3, ‐8, ‐9 activities, Cyt‐c and Bax levels and decreased Bcl‐2 levels. The concurrent incubation of NT2 cells with bleomycin/H2O2 and NAC (5 mM) for 24 h abolished bleomycin/H2O2‐dependent increases in Caspase‐3, ‐8, ‐9 activities, Bax and Cyt‐c levels and bleomycin/H2O2‐dependent decrease in Bcl‐2 level. Our results indicate that bleomycin/H2O2 induce apoptosis in NT2 cells by activating mitochondrial pathway of apoptosis, while NAC diminishes bleomycin/H2O2 induced apoptosis. We conclude that NAC has antagonistic effects on Bleomycin‐induced apoptosis in NT2 cells and causes resistance to apoptosis which is not a desired effect in eliminating cancer cells. J. Cell. Biochem. 114: 1685–1694, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
9.
A series of 13 phosphonium salts on the basis of pyridoxine derivatives were synthesized and their antibacterial activity against clinically relevant strains was tested in vitro. All compounds were almost inactive against gram-negative bacteria and exhibited structure-dependent activity against gram-positive bacteria. A crucial role of ketal protection group in phosphonium salts for their antibacterial properties was demonstrated. Among synthesized compounds 5,6-bis[triphenylphosphonio(methyl)]-2,2,8-trimethyl-4H-[1,3]dioxino[4,5-c]pyridine dichloride (compound 20) was found to be the most effective towards Staphylococcus aureus and Staphylococcus epidermidis strains (MIC 5 μg/ml). The mechanism of antibacterial activity of this compound probably involves cell penetration and interaction with genomic and plasmid DNA.  相似文献   
10.
Assessments of climate change impacts on forests and their vitality are essential for semi-arid environments such as Central Asia, where the mountain regions belong to the globally important biodiversity hotspots. Alterations in species distribution or drought-induced tree mortality might not only result in a loss of biodiversity but also in a loss of other ecosystem services. Here, we evaluate spatial trends and patterns of the growth-climate relationship in a tree-ring network comprising 33 juniper sites from the northern Pamir-Alay and Tien Shan mountain ranges in eastern Uzbekistan and across Kyrgyzstan for the common period 1935–2011. Junipers growing at lower elevations are sensitive to summer drought, which has increased in intensity during the studied period. At higher elevations, juniper growth, previously favored by warm summer temperatures, has in the recent few decades become negatively affected by increasing summer aridity. Moreover, response shifts are observed during all seasons. Rising temperatures and alterations in precipitation patterns during the past eight decades can account for the observed increase in drought stress of junipers at all altitudes. The implications of our findings are vital for the application of adequate long-term measures of ecosystem conservation, but also for paleo-climatic approaches and coupled climate-vegetation model simulations for Central Asia.  相似文献   
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