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981.
Mohamad Mehdi Aminaee Rasool Zare Hadi Zohdi 《Archives Of Phytopathology And Plant Protection》2013,46(7):678-688
The Rosa damascena has organic production and this plant is the most important economic crop in Kerman province. Roses have been used since the earliest times in rituals, cosmetics, perfumes, medicines and aromatherapy. The rose stem sawfly (Hartigia trimaculata) and rose stem girdler (Agrilus aurichalceus) are new and major pests of R. damascena in the Lalehzar region of Kerman province. These pests cause severe damage to plants by feeding stems and new management strategies for their control are continually being investigated. To investigate appropriate biological control agent in the region during 2005–2007, 184 isolates of fungi were collected from these pests. Isolation of fungi was achieved using standard methods. In this study, H. trimaculata and A. aurichalceus from R. damascena for the first time were recorded in Iran. Lecnicillium muscarium from H. trimaculata, L. muscarium from A. aurichalceus, Acremonium kiliense from H. trimaculata, and A. egyptiacum from A. aurichalceus have for the first time been recorded, and L. muscarium has been introduced as a suitable biological agent for control of these pests. 相似文献
982.
Nejla Stambouli Mehdi Dridi Ning-Ning Wei Asma Jlizi Abderahmen Bouraoui Amel Ben Ammar Elgaaied 《Journal of biomolecular structure & dynamics》2013,31(6):866-875
The chemokine receptor 5 (CCR5) belongs to the superfamily of serpentine G protein-coupled receptors (GPCRs). The DRY motif (Asp, Arg, Tyr) of the intracellular loop 2 (ICL2), which is highly conserved in the GPCRs has been shown to be essential for the stability of folding of CCR5 and the interaction with β-arrestin. But the molecular mechanism by which it recognizes and interacts with β-arrestin has not been elucidated. In the present study, we described the active state of the β-arrestin structure using normal mode analysis and characterized the binding cleft of CCR5-ICL2 with β-arrestin using SABRE© docking tool and molecular dynamics simulation. Based on our computational results, we proposed a mode of binding between the ICL2 loop of CCR5 and β-arrestin structure, and modeled the energetically stable β-arrestin/CCR5 complex. In view of CCR5’s importance as a therapeutic target for the treatment of HIV, this observation provides novel insight into the β-arrestin/CCR5 pathway. As a result, the current computational study of the detailed β-arrestin/CCR5 binding complex could provide the rationale for the development of next generation of HIV peptide inhibitors as therapeutic agents. 相似文献
983.
Mahmood Habibian Shahab Ghazi Mohammad Mehdi Moeini 《Biological trace element research》2013,153(1-3):205-211
This study evaluated the effects of supplemental dietary chromium (Cr) on the performance, carcass traits, and some serum parameters of broilers under a heat stress (23.9 to 37 °C cycling) condition. A total of 150 1-day-old broiler chicks (Cobb 500) according to a completely randomized design were assigned into five treatment groups. Each treatment consisted of three replicates and each replicate contained ten chicks. Treatments were supplemented with 0 (control), 600, and 1,200 μg kg?1 Cr in the form of Cr chloride (CrCl3) and Cr L-methionine from 1 to 49 days of age. Blood samples were collected from two birds in each replicate to determine serum parameters at 35 and 49 days of age. The body mass, feed intake, and conversion ratio were not influenced by dietary Cr (P?>?0.05). Dietary supplementation of Cr from either CrCl3 or Cr L-methionine caused increased serum concentrations of Cr (P?<?0.05), but had no effect on serum insulin and glucose concentrations at both sampling times (P?>?0.05). Serum triglycerides, very low-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol were also not significantly affected (P?>?0.05) by dietary treatments, whereas total cholesterol concentration decreased in chicks fed Cr L-methionine compared to the control (P?<?0.05). 相似文献
984.
Mehdi Razzaghi-Abyaneh Reza Saberi Anosheh Sharifan Mohammad-Bagher Rezaee Roghayeh Seifili Seyed-Ibrahim Hosseini Masoomeh Shams-Ghahfarokhi Mehdi Nikkhah Ismail Saberi Akram Amani 《Mycotoxin Research》2013,29(4):261-269
The ethyl acetate extract of leaves, seeds and flowers of Heracleum persicum, a medicinal plant of Iran (family Apiaceae) inhibited growth and aflatoxin (AF) production of Aspergillus parasiticus. On the basis of total dry weight growth inhibition by the leaf extract ranged from 17.1 to 36.9 %, by the flower extract from 32.2 to 75.6 %, and by the seed extract from 27.5 to 74.9 %. Production of AFB1 and AFG1 was inhibited in a dose-dependent manner, with a reduction of 88.5–100 % at the highest concentration of 8,000 μg/ml tested. The flower extract decreased ergosterol content of hyphae most significantly. Electron microscopy further revealed structural defects in the treated A. parasiticus including disruption of cytoplasmic membranous compartments, detachment of plasma membrane from the cell wall, and disorganization of hyphal compartments. Collapsed hyphae without conidiation, shorter branches and undifferentiated hyphal tips were also evident. The results indicate that H. persicum extract exerts antifungal and anti-AF activities by disrupting plasma membrane integrity and permeability mainly through interference with ergosterol biosynthesis. These results show that H. persicum can serve as a potent and safe alternative for inhibiting toxigenic aspergilli growth and thus preventing AF contamination of foods and feeds. 相似文献
985.
Eva Mikaelsson Anders ?sterborg Mahmood Jeddi-Tehrani Parviz Kokhaei Mahyar Ostadkarampour Reza Hadavi Mehran Gholamin Mehdi Akhondi Fazel Shokri Hodjattallah Rabbani H?kan Mellstedt 《PloS one》2013,8(6)
Proline/arginine-rich end leucine-rich repeat protein (PRELP) belongs to the small leucine-rich proteoglycan (SLRP) family, normally expressed in extracellular matrix of collagen-rich tissues. We have previously reported on another SLRP, fibromodulin (FMOD) in patients with chronic lymphocytic leukemia (CLL). PRELP is structurally similar to FMOD with adjacent localization on chromosome 1 (1q32.1). As cluster-upregulation of genes may occur in malignancies, the aim of our study was to analyze PRELP expression in CLL. PRELP was expressed (RT-PCR) in all CLL patients (30/30), as well as in some patients with mantle cell lymphoma (3/5), but not in healthy donor leukocytes (0/20) or tumor samples from other hematological malignancies (0/35). PRELP was also detected in CLL cell-lines (4/4) but not in cell-lines from other hematological tumors (0/9). PRELP protein was detected in all CLL samples but not in normal leukocytes. Deglycosylation experiments revealed a CLL-unique 38 kDa core protein, with an intact signal peptide. This 38 kDa protein was, in contrast to the normal 55 kDa size, not detected in serum which, in combination with the uncleaved signal peptide, suggests cellular retention. The unique expression of a 38 kDa PRELP in CLL cells may suggest involvement in the pathobiology of CLL and merits further studies. 相似文献
986.
Ali Riazi Philippa C. R. Strong Russell Coleman Wangxue Chen Tomoko Hirama Henk van Faassen Matthew Henry Susan M. Logan Christine M. Szymanski Roger MacKenzie Mehdi Arbabi Ghahroudi 《PloS one》2013,8(12)
Campylobacter jejuni is the leading cause of bacterial foodborne illness in the world, with symptoms ranging from acute diarrhea to severe neurological disorders. Contaminated poultry meat is a major source of C. jejuni infection, and therefore, strategies to reduce this organism in poultry, are expected to reduce the incidence of Campylobacter-associated diseases. We have investigated whether oral administration of C. jejuni-specific single-domain antibodies would reduce bacterial colonization levels in chickens. Llama single-domain antibodies specific for C. jejuni were isolated from a phage display library generated from the heavy chain IgG variable domain repertoire of a llama immunized with C. jejuni flagella. Two flagella-specific single-domain antibodies were pentamerized to yield high avidity antibodies capable of multivalent binding to the target antigen. When administered orally to C. jejuni-infected two-day old chicks, the pentabodies significantly reduced C. jejuni colonization in the ceca. In vitro, the motility of the bacteria was also reduced in the presence of the flagella-specific pentabodies, suggesting the mechanism of action is through either direct interference with flagellar motility or antibody-mediated aggregation. Fluorescent microscopy and Western blot analyses revealed specific binding of the anti-flagella pentabodies to the C. jejuni flagellin. 相似文献
987.
Chantal C. H. J. Kuijpers Cathy B. Moelans Henk-Jan van Slooten Anja Horstman John W. J. Hinrichs Shaimaa Al-Janabi Paul J. van Diest Mehdi Jiwa 《PloS one》2013,8(12)
Background
HER-2 is a prognostic and predictive marker, but as yet no technique is perfectly able to identify patients likely to benefit from HER-2 targeted therapies. We aimed to prospectively assess the added value of first-line co-testing by IHC, and multiplex ligation-dependent probe amplification (MLPA) and chromogenic in situ hybridization (CISH).Methods
As local validation, HER-2 MLPA and CISH were compared in 99 breast cancers. Next, we reviewed 937 invasive breast cancers, from 4 Dutch pathology laboratories, that were prospectively assessed for HER-2 by IHC and MLPA (and CISH in selected cases).Results
The validation study demonstrated 100% concordance between CISH and MLPA, if both methods were assessable and conclusive (81.8% of cases). Significant variation regarding percentages IHC 0/1+ and 2+ cases was observed between the laboratories (p<0.0001). Overall concordance between IHC and MLPA/CISH was 98.1% (575/586) (Kappa = 0.94). Of the IHC 3+ cases, 6.7% failed to reveal gene amplification, whereas 0.8% of the IHC 0/1+ cases demonstrated gene amplification. Results remained discordant after retrospective review in 3/11 discordant cases. In the remaining 8 cases the original IHC score was incorrect or adapted after repeated IHC staining.Conclusions
MLPA is a low-cost and quantitative high-throughput technique with near perfect concordance with CISH. The use of MLPA in routinely co-testing all breast cancers may reduce HER-2 testing variation between laboratories, may serve as quality control for IHC, will reveal IHC 0/1+ patients with gene amplification, likely responsive to trastuzumab, and identify IHC 3+ cases without gene amplification that may respond less well. 相似文献988.
989.
Kathleen A. Trychta Emily J. Heathward Agnieszka Sulima Susanne Bäck Mehdi Farokhnia Christopher T. Richie 《Biomarkers》2013,18(8):756-765
AbstractContext: Endoplasmic reticulum (ER) calcium depletion is associated with diverse diseases, including cardiac, hepatic, and neurologic diseases.Objective: The aim of the present study was to identify and characterize an endogenous protein that could be used to monitor ER calcium depletion comparably to a previously described exogenous reporter protein.Materials and methods: The use of a selective esterase-fluorescein diester pair allowed for carboxylesterase activity in extracellular fluid to be measured using a fluorescent readout. Cell culture media from three different cell lines, rat plasma, and human serum all possess quantifiable amounts of esterase activity.Results: Fluorescence produced by the interaction of carboxylesterases with a fluorescein diester substrate tracks with pharmacological and physiological inducers of ER calcium depletion. The fluorescence measured for in vitro and in vivo samples were consistent with ER calcium depletion being the trigger for increased esterase activity.Discussion: Decreased luminal ER calcium causes ER resident esterases to be released from the cell, and, when assessed concurrently with other disease biomarkers, these esterases may provide insight into the role of ER calcium homeostasis in human diseases.Conclusion: Our results indicate that carboxylesterases are putative markers of ER calcium dysfunction. 相似文献
990.
Jean-Jacques Helesbeux Damien Peyronnet Mehdi Labaïed Philippe Grellier François Frappier Denis Seraphin 《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):431-437
The synthesis of 1,2-dioxolane derivatives in two different acetophenone series, as simplified models of natural coumarins is described. 2-Acetyl-3-acetoxy-4-(3-hydroperoxy-3-methylbut-1-enyl)phenyl acetate and 2-acetyl-5-acetoxy-4-(3-hydroperoxy-3-methylbut-1-enyl) phenyl acetate synthons are used as precursors to these structures. In vitro antimalarial activity of the 1,2-dioxolane derivatives has been investigated. 相似文献