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31.
Sahar Gholi-Tolouie Nemat Sokhandan-Bashir Mahdi Davari Mohammad Sedghi 《European journal of plant pathology / European Foundation for Plant Pathology》2018,151(1):101-116
Cucumber mosaic virus (CMV) is one of the most important plant viruses responsible for sharp reductions in the production of many cultivated plants. Activities of antioxidant enzymes, photosynthetic capacity, proline and total soluble carbohydrates (TSC) content were measured in the leaves of tomato (Solanum lycopercicum cv. Falat) plants treated with phytohormones (salicylic and jasmonic acids and their combination) and inoculated with CMV at 0, 1, 2, 4, 6, 8, and 15 days after the treatments. Based on the results, catalase (CAT) activity decreased in the healthy and infected plants, but peroxidase (POD) activity increased in the CMV-infected plants signifying that POD is more active in H2O2 scavenging in tomato. Because the hormone treatments inhibited the reduction in the enzyme activity, it may be considered as a controlling method against CMV. Superoxide dismutase (SOD) activity was lower in the control until 6 days post inoculation (dpi), but increased after 8 dpi. The infected plants and the hormone-treated plants showed an increased SOD activity from 0 to 15 dpi. Phenylalanine ammonia lyase (PAL) activity also increased in all the treatments over the time period (0-15 dpi). Net photosynthesis (NP) rate and chlorophyll content decreased under the virus infection and hormone treatment, whereas control plants had the highest NP and chlorophyll content. Proline accumulation occurred in the infected and hormone- treated plants, but TSC content decreased in comparison to the control. Reduction of TSC content was not significant in the hormone and virus- treated plants. Expression of CMV coat protein gene (CMV-CP) was decreased by approximately 34% in SA+JA+CMV treatment in comparison to the CMV-infected plants. In conclusion, CMV had harmful effect on physiological traits of tomato plants, but hormone application induced resistance. This resistance may be accomplished through the combination of both hormone-related signaling pathways which likely established a strong resistance network together. 相似文献
32.
Sahar Moghaddasi Fathallah Karimzadeh Hamid Reza Khazaei Reza Khorassani Amir Lakzian 《Archives of Agronomy and Soil Science》2017,63(8):1108-1120
Zinc oxide-engineered nanoparticles (ZnO ENPs) have received the most attention in recent years. This increasing interest has been directed towards studying the environmental fate and effects of ZnO ENPs on ecological terrestrial species. In this study, ZnO NPs were synthesized by atmospheric pressure solution evaporation method and were coated or uncoated with humic acid (HA). The root uptakes of uncoated and HA-coated ZnO NPs and zinc (Zn) were investigated by gel-grown cucumber. Two ZnO levels (1 and 200 µM) were applied in the form of coated (T3) and non-coated (T2) NPs or bulk particles (T1). The results showed that coating NPs by HA increases zeta potential of NPs and decreases their aggregation size due to the increase in the repulsion forces among the particles. Addition of 1 mgL?1 ZnO into gel chamber enhanced root and shoot biomass; however, the shoot growth was higher in the presence of NPs compared to its bulk counterpart. Moreover, greater phytotoxicity of ZnO from the source of NPs than bulk particles in shoot was observed. Scanning electron microscopy results showed a clear evidence of the penetration of NPs into root cells. 相似文献
33.
Sarfraz Ali Shad Ali H. Sayyed Sahar Fazal Mushtaq A. Saleem Syed Muhammad Zaka Muhammad Ali 《Journal of pest science》2012,85(1):153-162
Spodoptera litura Fab. (Lepidoptera, Noctuidae) is a polyphagous pest and has been shown to be resistant to a wide range of insecticides, which
has led to sporadic out breaks of the pest and failure of crops. We were interested to establish if resistance to insecticides
is diverse in different populations of S. litura collected from various areas with variable temperatures. We collected S. litura from eight different locations and compare the toxicity of insecticides. Resistance to the pyrethroids ranged from 20- to
11,700-fold compared with the Lab-PK (laboratory susceptible population). The resistance to bifenthrin was the lowest in a
population collected from Multan and the highest to esfenvalerate in a population collected from Lodhran. Similarly, very
high level of resistance to spinosad, indoxacarb, and methoxyfenozide was observed in all eight populations. In contrast,
resistance to organophosphates was significantly lower than the pyrethroids, spinosad, indoxacarb, and methoxyfenozide, while
toxicity of emamectin to field populations was similar to the Lab-Pk. The results are discussed in relation to integrated
pest management (IPM) for S. litura with special reference to management of field evolved resistance to insecticides. 相似文献
34.
Samaneh Saberi Kazem Zendehdel Sahar Jahangiri Yeganeh Talebkhan Afshin Abdirad Nazanin Mohajerani Maryam Bababeik Najmeh Karami Maryam Esmaili Akbar Oghalaie Parisa Hassanpour Neda Amini Mohammad Ali Mohagheghi Mahmoud Eshagh Hossieni Marjan Mohammadi 《Iranian Biomedical Journal》2012,16(4):179-184
Background
Attempts for early detection of gastric cancer have recently focused on host''s genetic susceptibility factors and gene-environment interactions. We have, herein, studied the association of MTHFR C677T single nucleotide polymorphism (SNP) and its interaction with Helicobacter pylori infection, smoking, age and gender on the risk of gastric cancer among an Iranian population.Methods
Gastric cancer patients (n = 450) and cancer-free controls (n = 780) were studied for serum H. pylori-specific IgG antibodies by ELISA and MTHFR C677T polymorphism (SNP) by PCR-RFLP. Demographic and life style data were collected through patient interviews. Unconditional logistic regression model estimated odds ratio (OR) and the corresponding 95% confidence intervals (CI).Results
The interactions of MTHFR genotype with H. pylori infection (P = 0.03), age (P = 0.049) and gender (P = 0.007) were statistically significant. Accordingly, MTHFR C677T carriers who were also positive for H. pylori infection exhibited 80% (OR = 1.8, 95% CI = 1.0-2.9) significant excess risk of non-cardia gastric cancer. Furthermore, subjects over the age of 50 or female subjects carrying MTHFR C677T SNP showed 40 (OR = 1.4, 95% CI = 1.0-2.0) and 100 (OR = 2.0, 95% CI = 1.2-3.2) percent increased risk of gastric cancer, respectively.Conclusion
MTHFR C677T SNP seems to increase the risk of gastric cancer and the effect is significantly inflated by interactions with H. pylori infection, age and gender. Key Words: Helicobacter pylori, Smoking, Gender identity, Age group, Methylenetetrahydrofolate reductase 相似文献35.
Sahar Alsaidi Nadjet Cornejal Oneil Mahoney Claudia Melo Neeharika Verma Thierry Bonnaire Theresa Chang Barry R. O&#x;Keefe James Sailer Thomas M. Zydowsky Natalia Teleshova Jos A. Fernndez Romero 《Marine drugs》2021,19(8)
Over 182 million confirmed cases of COVID-19 and more than 4 million deaths have been reported to date around the world. It is essential to identify broad-spectrum antiviral agents that may prevent or treat infections by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) but also by other coronaviruses that may jump the species barrier in the future. We evaluated the antiviral selectivity of griffithsin and sulfated and non-sulfated polysaccharides against SARS-CoV-1 and SARS-CoV-2 using a cytotoxicity assay and a cell-based pseudoviral model. The half-maximal cytotoxic concentration (CC50) and half-maximal effective concentration (EC50) were determined for each compound, using a dose-response-inhibition analysis on GraphPad Prism v9.0.2 software (San Diego, CA, USA). The therapeutic index (TI = CC50/EC50) was calculated for each compound. The potential synergistic, additive, or antagonistic effect of different compound combinations was determined by CalcuSyn v1 software (Biosoft, Cambridge, UK), which estimated the combination index (CI) values. Iota and lambda carrageenan showed the most potent antiviral activity (EC50 between 3.2 and 7.5 µg/mL). Carrageenan and griffithsin combinations exhibited synergistic activity (EC50 between 0.2 and 3.8 µg/mL; combination index <1), including against recent SARS-CoV-2 mutations. The griffithsin and carrageenan combination is a promising candidate to prevent or treat infections by SARS-CoV-1 and SARS-CoV-2. 相似文献
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37.
Adsorption of phenolic compounds and browning products in white wines by yeasts and their cell walls 总被引：1，自引：0，他引：1
Razmkhab S Lopez-Toledano A Ortega JM Mayen M Merida J Medina M 《Journal of agricultural and food chemistry》2002,50(25):7432-7437
Dehydrated yeast cells at variable concentrations were used as fining agents to decrease the color of white wines with two different degrees of browning (0.153 and 0.177 au, measured at 420 nm). Both wines showed a linear decrease of browning with increasing yeast concentration. However, in terms of efficiency, the yeasts exhibited a higher color lightening at greater concentrations acting on the darker wine. This suggests a preferential retention of some types of yellow-brown compounds that could increase their concentrations at the higher degree of browning. To confirm the role of yeast cell walls in the retention of browning compounds and to evaluate their potential use as fining agents, they were applied at variable concentrations to a browned wine (0.175 au). The cell walls were found to be the active support for the adsorption of browning compounds, but their efficiency was much lower than that of an equivalent amount of the yeast cells from which they were obtained. Finally, HPLC determinations of low-molecular-weight phenolic compounds showed flavan-3-ol derivatives to be significantly retained by both yeasts and their cell walls. 相似文献
38.
Sahar Sedaghat 《International Journal of Fruit Science》2018,18(1):14-28
ABSTRACTThe aim of this study was to assess the effects of invertase and amylase enzyme activities on starch, individual sugars, and organic acid changes during developmental stages (before caprification, fruit set, softening, and senescence) in Ficus carica L.cv Sabz with three replicates. The initial stage of fruit development showed the highest stored carbohydrates and the lowest total sugar and whilst the senescence stage obtained the lowest stored carbohydrates and the highest total sugar. Furthermore, high-performance of liquid chromatograph analysis revealed that the value of glucose and fructose significantly increased as fruits developed. Citric acid was the most abundant organic acid followed by malic acid. Moreover, invertase activity increased sharply before the caprification stage up to the senescence stage. We found that fig fruit possess α- and β-amylase activities, which increased dramatically up to the ripening stage and then slightly decreased at the senescence stage. The present study showed that this cultivar is a rich fruit based on glucose and fructose as well as citric and malic acid. 相似文献
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40.
M. Mejri L. Fonseca J. M. S. Cardoso M. L. Ben Jamâa I. Abrantes 《Forest Pathology》2016,46(6):663-665
Bursaphelenchus tusciae is reported for the first time in Tunisia and North Africa, associated with the insect Hylurgus ligniperda Fabricius (Coleoptera: Curculionidae: Scolytinae). Nematode identification was based on restriction fragment length polymorphism analysis and sequencing of the internal transcribed spacer (ITS) regions of ribosomal DNA. Phylogenetic analysis revealed that Tunisian B. tusciae clusters together with two other B. tusciae isolates forming a separate group close to B. hildegardae and B. eggersi. As H. ligniperda is among maritime pine scolytids pests in Tunisia and is widely distributed in North Africa, this study is an important contribution to the knowledge of Bursaphelenchus species associated with bark beetles of pine forests in Tunisia and North Africa. 相似文献