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81.
Journal of Plant Growth Regulation - In order to investigate the effect of wastewater on the soil minerals movement, irrigation water use efficiency (IWUE) and leaf nutrients uptake of...  相似文献   
82.
One of the most successful strategies in designing peptide-based cancer vaccines is modifying natural epitope peptides to increase their binding strength to human leukocyte antigens (HLAs). Anchor-modified Mart-1 peptide (ELAGIGILTV) is among the artificial epitope peptides with the highest binding affinity for HLA-A*0201. In this study, by fluorescence labeling of its either C- or N-terminus with Nε-(5-carboxyfluorescein)-l -lysine, we not only made it traceable but also drastically increased its binding strength to HLA-A*0201. HLA streptamer, for the first time, is introduced for measuring the binding constants (Ka) of the labeled peptides. The affinity of the labeled peptides for the HLA-A*201 of the MCF-7 cells was extraordinarily high and co-incubating them with the highest possible amount of the unlabeled peptide, as a competitor, did not significantly prohibit them from binding to the HLA. The reproducibility of the obtained results was confirmed by using the T2 cell line. The HLA-deficient K562 cell line was used as the negative control. With in silico simulations, we found two hydrophobic pockets on both sides of HLA-A*0201 for anchoring the C- or N-terminal 5-carboxyfluorescein probe, which can explain the extraordinary affinity of the labeled peptides for the HLA-A*0201.  相似文献   
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We have developed a facile and highly sensitive sorbent for cadmium and lead ions. It is based on Fe3O4 nanoparticles functionalized with a derivative of picoline and was characterized by scanning electron microscopy, differential thermographic analysis, and elemental analysis. The material can be applied to the preconcentration of lead and cadmium ions. Factors such as the type, concentration and volume of eluent, the pH of the sample solution, the time for extraction, and the volume of the sample were studied. The effects of a variety of ions on preconcentration and recovery of these ions were also investigated. The ions were determined by FAAS, and the limits of detection are <0.8 and <0.061???g?L?1 for lead and cadmium, respectively. Recoveries and precisions are >98.0?% and <1.3?%, respectively. The method was validated by analyzing several certified leaf reference materials.  相似文献   
86.

Background

Furin represents a crucial member of secretory mammalian subtilase, the Proprotein Convertase (PC) or Proprotein Convertase Subtilisin/Kexin (PCSK) superfamily. It has been linked to cancer, tumorgenesis, viral and bacterial pathogenesis. As a result it is considered a major target for intervention of these diseases.

Methodology/Principal Findings

Herein, we report, for the first time, the synthesis and biological evaluation of a newly designed potent furin inhibitor that contains a highly reactive beta-turn inducing and radical generating “enediynyl amino acid” (Eda) moiety. “Eda” was inserted between P1 and P1′ residues of hfurin98–112 peptide, derived from the primary cleavage site of furin''s own prodomain. The resulting hexadecapeptide derivative inhibited furin in vitro with IC50 ∼40 nM when measured against the fluorogenic substrate Boc-RVRR-MCA. It also inhibited furin-mediated cleavage of a fluorogenic peptide derived from hSARS-CoV spike protein with IC50 ∼193 nM. Additionally it also blocked furin-processing of growth factors proPDGF-A, B and VEGF-C that are linked to tumor genesis and cancer. Circular dichroism study showed that this inhibitor displayed a predominantly beta-turn structure while western blots confirmed its ability to protect furin protein from self degradation.

Conclusion/Significance

These findings imply its potential as a therapeutic agent for intervention of cancer and other furin-associated diseases.  相似文献   
87.

Depression and Anxiety are two important public health problems that are known to be associated with viral infections. The association between the intake of nutrients such as zinc and copper with symptoms of depression has been studied previously. The aim of the current study was to investigate the association between depression with human T cell lymphotropic virus type 1 (HTLV-1) infection and serum content of zinc and copper in a large Iranian population cohort. The study population consisted of 279 HTLV-1-positive patients who were identified after recruitment as part of a large cohort study: the Mashhad Stroke and Heart Association Disorder (MASHAD) study. They were divided into two groups of diagnosed with or without depression based on their symptoms. Serum zinc and copper levels of all subjects were measured using the flame atomic absorption spectrometry. The population sample comprised of 279 individuals infected with HTLV-1 of whom 192 (68.8%) were women. The mean serum zinc in the group with and without depression was 78.69 ± 13.79 μg/dl and 86.87 ± 19.44 μg/dl, respectively (p < 0.001). Also, the serum copper level was higher in the depressive group (116.75 ± 39.56) than in the non-depressive group (104.76 ± 30.77) (p 0.004). The association between serum zinc and copper with depression in HTLV-1-infected patients which was shown in this study could be considered in the treatment strategies in these patients.

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88.
The anti-phytoplasma activities of surfactin (derived from Iranian native Bacillus subtilis isolates) and tetracycline towards Candidatus "Phytoplasma aurantifolia", the agent of lime Witches' broom disease, were investigated. HPLC was used to quantify the surfactin production in four previously characterized native surfactin-producing strains, and the one producing the highest amount of surfactin (about 1,500 mg/l) was selected and cultivated following optimized production and extraction protocols. Different combinations of purified surfactin and commercial tetracycline were injected into artificially phytoplasmainfected Mexican lime seedlings using a syringe injection system. An absolute quantitative real-time PCR system was developed to monitor the phytoplasma population shifts in the lime phloem during 3 months following the injections. The results revealed that the injections of surfactin or tetracycline had a significant inhibitory effect on Candidatus "P. aurantifolia". However, the combined treatment with both surfactin and tetracycline (1:1) resulted in the highest inhibition due to a synergic effect, which suppressed the phytoplasma population from about 2×10(5) to less than 10 phytoplasma units/g plant tissue.  相似文献   
89.
In order to study the immunomodulatory effects of decaffeinated green tea extract on rainbow trout, a study with a 30-day feeding trial was conducted. Commercial diets with graded levels of decaffeinated green tea extract, 20 mg (T1), 100 mg (T2), 500 mg (T3) per kg feed were prepared. 120 rainbow trout (35 ± 3 g) were randomly assigned to 4 groups in triplicates and fed one of the 3 experimental diets formulated or control diet. After feeding trial, 12 fish from each group were sampled for analysis of some immunological parameters. Remaining fish were injected with 0.5 ml of chicken red blood cell (C-RBC) suspension (2%) intraperitoneally on days 5 and 15 after feeding trial. Results of the current study showed that the inclusion of 20 mg kg-1 green tea (T1) in fish diet enhanced the serum bactericidal activity against Yersinia ruckeri, while significant elevation of lysozyme activity was shown in T2 group. Anti-trypsin activity due to α1-antiprotease was significantly higher in T1 and T2 groups while peroxidase content showed significant increase in all treatment groups compared to control group. Hemagglutination antibody titer against C-RBC was significantly higher in fish administered with 100 mg kg(-1) green tea (T2). Our findings showed that decaffeinated green tea in lower doses of administration could be optimum to enhance the immunity of rainbow trout.  相似文献   
90.
The effects of dietary whole cell yeast (Saccharomyces cerevisiae), n-3 HUFA-enriched yeast and treated yeast cells with beta-mercapto-ethanol (2ME) on immunity, growth performance and disease resistance to Yersinia ruckeri were investigated in Oncorhynchus mykiss. During 30 days, juvenile rainbow trout were fed diets supplemented with different forms of yeast at 5 × 10(7) CFU g(-1) or a control diet. After the feeding trial, remaining fish of each treatment were challenged by pathogenic Yersinia ruckeri and kept under observation for 14 days to record clinical signs and daily mortality rate. Yeast supplementation in all treatment groups significantly promoted the growth performance compared to control group. A significantly increase was also observed in immune responses in juvenile fish fed 2ME-treated yeast diet. More ever, the lowest fish mortality was obtained in this treatment group. The present results show that a diet supplemented with 2ME-treated yeast stimulates the immune system and growth of juvenile rainbow trout thus enhancing their resistance against Y. ruckeri.  相似文献   
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