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81.
Olfactory learning may allow insects to forage optimally by more efficiently finding and using favourable food sources. Although
olfactory learning has been shown in bees, insect herbivores and parasitoids, there are fewer examples from polyphagous predators.
In this study, olfactory learning by a predatory coccinellid beetle is reported for the first time. In laboratory trials,
adults of the aphidophagous ladybird Coccinella septempunctata did not prefer the odour of one aphid-infested barley cultivar over another. However, after feeding on aphids for 24 h on
a cultivar, they preferred the odour of that particular cultivar. The mechanism appeared to be associative learning rather
than sensitisation. Although inexperienced ladybirds preferred the odour of an aphid-infested barley cultivar over uninfested
plants of the same cultivar, after feeding experience on a different cultivar this preference disappeared. This may indicate
the acquisition and replacement of olfactory templates. The odour blends of the different aphid-infested barley cultivars
varied qualitatively and quantitatively, providing a potential basis for olfactory discrimination by the ladybird. The results
show that predatory coccinellids can learn to associate the odour of aphid-infested plants with the presence of prey, and
that this olfactory learning ability is sensitive enough to discriminate variability between different genotypes of the same
plant. 相似文献
82.
Moeini MM Kiani A Mikaeili E Shabankareh HK 《Biological trace element research》2011,144(1-3):529-537
Forty heifers at the late stage of gestation were randomly assigned into five groups. Heifers were balanced for age, weight, and time of calving in each group. Four and 2?weeks before expected time of calving, the heifers were injected with 0?ml (C), 10?ml (T1), 20?ml (T2), 30?ml (T3), and 40?ml (T4) Se and VE supplements, respectively. Each milliliter of the supplement contained of 0.5?mg Se as sodium selenite and 50?IU of dl-alpha-tocopheryl acetate. Blood samples were collected from the heifers 4?weeks before expected calving and at calving day and from the calves at birth and 7?days of age. The serum Se and immunoglobulin G (IgG) concentrations, white blood cell and differential leukocyte counts were measured. The Se concentrations in the sera of the heifers before the injections of Se and VE supplements were the same among the groups (P?>?0.05), but after calving were significantly increased in the treated heifers (P?0.05). Similarly, the serum Se levels of calves of the treated heifers were higher (P?0.05). The Se concentrations in the colostrums of the heifers were affected by treatments (P?0.05). Colostrum and daily milk productions at 8-week lactation were increased in treated heifers compared with the controls (P?0.05). Likewise, the milk somatic cell counts decreased in the treated heifers compared with the controls. The changes of the mean serum IgG levels did not differ among calves (P?>?0.05). The white blood cell counts were higher in calves of heifers in groups T3 and T4 compared with the control group at 7?days of age (P?0.05). 相似文献
83.
El Husseiny NM Said ES El Shahat Mohamed N Othman AI 《Biological trace element research》2011,143(3):1451-1460
The aim of this study was to confirm if there is a link between the alteration in blood levels of trace elements (chromium,
copper, lead, cadmium, and zinc) and dehydroepiandrosterone sulfate (DHEAS) in healthy and diabetic states. This study is
the first study to test these parameters in Egyptians. The study included 150 subjects divided into the following four groups:
healthy middle-aged, healthy elderly, middle-aged diabetics, and elderly diabetics. Our results revealed a statistically significant
decrease in the level of DHEAS in the elderly compared to middle-aged healthy and diabetic groups (p < 0.05). There was a significant difference between the middle-aged groups with respect to zinc, copper, chromium, and cadmium
levels. Zinc and copper were lower in the diabetic subjects while chromium and cadmium were higher in the same group in comparison
to healthy subjects. In the elderly groups, there were significant increases in chromium and cadmium levels in diabetic subjects
rather than healthy ones. There was a significant increase in the thiobarbituric acid reactive substance level in the elderly
healthy and diabetic groups and a significant decrease in the glutathione level in the elderly groups. There was no correlation
between the levels of trace elements and DHEAS or between the levels of DHEAS, oxidants, and antioxidants in all of the tested
groups. In conclusion, only the DHEAS level was correlated with age. There was no difference between the diabetic and healthy
groups with respect to the levels of trace elements, with the exception of chromium and cadmium, which suggests the effect
of pollution on the pathogenesis of diabetes in Egyptians. No correlation existed between the levels of DHEAS and trace elements,
oxidants, and antioxidants. Finally, we believe that there is a large regional variation in the levels of trace elements due
to different environmental exposure and nutritional factors which are responsible for contradictory results regarding the
pathogenesis of diseases related to alterations in the levels of trace elements. 相似文献
84.
Rani A Afzali B Kelly A Tewolde-Berhan L Hackett M Kanhere AS Pedroza-Pacheco I Bowen H Jurcevic S Jenner RG Cousins DJ Ragheb JA Lavender P John S 《Journal of immunology (Baltimore, Md. : 1950)》2011,187(7):3721-3729
Blockade of IL-2R with humanized anti-CD25 Abs, such as daclizumab, inhibits Th2 responses in human T cells. Recent murine studies have shown that IL-2 also plays a significant role in regulating Th2 cell differentiation by activated STAT5. To explore the role of activated STAT5 in the Th2 differentiation of primary human T cells, we studied the mechanisms underlying IL-2 regulation of C-MAF expression. Chromatin immunoprecipitation studies revealed that IL-2 induced STAT5 binding to specific sites in the C-MAF promoter. These sites corresponded to regions enriched for markers of chromatin architectural features in both resting CD4 and differentiated Th2 cells. Unlike IL-6, IL-2 induced C-MAF expression in CD4 T cells with or without prior TCR stimulation. TCR-induced C-MAF expression was significantly inhibited by treatment with daclizumab or a JAK3 inhibitor, R333. Furthermore, IL-2 and IL-6 synergistically induced C-MAF expression in TCR-activated T cells, suggesting functional cooperation between these cytokines. Finally, both TCR-induced early IL4 mRNA expression and IL-4 cytokine expression in differentiated Th2 cells were significantly inhibited by IL-2R blockade. Thus, our findings demonstrate the importance of IL-2 in Th2 differentiation in human T cells and support the notion that IL-2R-directed therapies may have utility in the treatment of allergic disorders. 相似文献
85.
Rapid growth in the biotechnological industry and production has put tremendous pressure on the biological methods that may be used according to the guidelines of green chemistry. However, despite continuing dramatic increases in published research on organic biotransformation by microorganisms, more research exists with microalgae. Our efforts in transforming chemicals such as organic compounds for the production of functionalized products help to lessen the environmental effects of organic synthesis. These biotransformations convert organic contaminants to obtain carbon or energy for growth or as cosubstrates. This review aims to focus on the potential of microalgae in transformation, conversion, remediation, accumulation, degradation, and synthesis of various organic compounds. However, these technologies have the ability to provide the most efficient and environmentally safe approach for inexpensive biotransforming of a variety of organic contaminants, which are most industrial residues. In addition, the recent advances in microalgal bioactivity were discussed. 相似文献
86.
87.
Omid Aryani Masoumeh Dehghan Manshadi Mahdi Tondar Elham Khalili Behnam Kamalidehghan Fatemeh Ahmadipour Somayeh Fani Massoud Houshmand 《Molecular biology reports》2014,41(9):6211-6214
Pompe disease or glycogen storage disease type II is a glycogen storage disorder associated with malfunction of the acid α-glucosidase enzyme (GAA; EC.3.2.1.3) leading to intracellular aggregations of glycogenin muscles. The infantile-onset type is the most life-threatening form of this disease, in which most of patients suffer from cardiomyopathy and hypotonia in early infancy. In this study, a typical case of Pompe disease was reported in an Iranian patient using molecular analysis of the GAA gene. Our results revealed a new c.1824_1828dupATACG mutation in exon 13 of the GAA gene. In conclusion, with the finding of this novel mutation, the genotypic spectrum of Iranian patients with Pompe disease has been extended, facilitating the definition of disease-related mutations. 相似文献
88.
89.
Duha Alomar Azzmer Azzar Abdul Hamid Elham Khosrowabadi Ronnie G. Gicana Robert J. Lamis Fahrul Huyop 《Bioremediation Journal》2014,18(1):12-19
Arthrobacter sp. strains D2 and D3 and Labrys sp. strain D1 capable of degrading 20 mM monochloroacetic acid (MCA) were isolated from soil contaminated with herbicides and pesticides. All three isolates were able to grow on MCA as the sole source of carbon and energy with concomitant chloride ion release in the growth medium (19 mM). Strains D2 and D3 (cells doubling time 7 ± 0.3 h) grew four times faster than D1 (26 ± 0.1 h). Strain D2 was then further investigated and could also grow in 10 mM of monobromoacetic acid (MBA), 2,2-dichloropropionic acid (2,2DCP), d,l-2-chloropropionic acid (D,L2CP), l-2-chloropropionic acid (L-2CP), d-2-chloropropionic acid (D-2CP), and glycolate as the sole sources of carbon and energy. Dehalogenase gene amplification using group I primers revealed a 410-bp polymerase chain reaction (PCR) product, but there was none using group II primers. The partial amino acid sequence analysis of group I DehD2 dehalogenase showed at least 32% identity to the corresponding regions of DehE, DhlIV, DehI, and D,L-DEX, with key amino acid residues Ser188, Ala187, and Asp189. These amino acid residues were involved in substrate binding and catalysis and were conserved in the partial amino acid sequence. 相似文献
90.
Elham Rismani Hamzeh Rahimi Seyed Shahriar Arab Kayhan Azadmanesh Morteza Karimipoor Ladan Teimoori-Toolabi 《International journal of peptide research and therapeutics》2018,24(1):49-60
Wnt signaling pathway plays a major role in the regulation of cell proliferation, migration, tissue homeostasis, tumor progression and cancer. This pathway can be antagonized by different proteins such as DKK proteins, which disrupt the initiatory complex (Frizzled–LRP6 complex). Therefore, interruption of its formation could be a promising strategy for the design of Low-density lipoprotein receptor-Related Protein 6 (LRP6) inhibitors. A computational study was conducted in order to assist in the design of inhibitory peptides against LRP6 as co-receptor of frizzled. Twelve fragments as peptide derivatives of natural ligand of LRP6 receptor (DKK1) were designed using the information from the analysis of the DKK1_C/LRP6 complex, hot spot residues and the secondary structure. These fragments were based on cys2 domain of DKK1. The designed peptides were energy minimized by molecular dynamics simulations in the presence and absence of LRP6 receptor and their binding affinities were investigated via molecular docking using ClusPro, HADDOCK and PRODIGY webservers. Finally, the stability and free energy of binding in peptides were calculated by FoldX software. The results showed that four designed peptides had the highest affinity (the interaction energy: ?10.2867, ?10.1388, ?7.94339 and ?7.57536 kcal/mol) to interact with the receptor which showed the most interacting residues and the lowest free energy of binding. Also, the RMSD, RMSF and RoG of the protein–peptide complex exhibited less structural fluctuations which can be linked to the stability of peptides associated to the receptor. These peptides may be considered as candidates for inhibiting Wnt signaling pathway through LRP6 receptor. 相似文献