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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
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Mamdouh M. Nemat Alla Nemat M. Hassan Zeinab M. El-Bastawisy 《Pesticide biochemistry and physiology》2007,89(3):198-205
The recommended field dose of rimsulfuron, imazethapyr, alachlor, atrazine or fluometuron differentially reduced shoot fresh and dry weight of 10-day-old maize seedlings as well as leaf protein content during the following 12 days. These reductions seemed consistent during the whole period with fluometuron, atrazine and alachlor but appeared to be nullified by the 5th day of treatment with rimsulfuron and imazethapyr. On the other hand, all herbicides mostly provoked significant inhibitions in specific activities of phosphoenolpyruvate carboxylase (PEPC, EC 4.1.1.31), malate dehydrogenase (MDH, EC 1.1.1.82), pyruvate phosphate dikinase (PPDK, EC 2.7.9.1) and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco, EC 4.1.1.39) in leaves during the first 2 days. Thereafter, the inhibition was recovered in samples treated with rimsulfuron and imazethapyr, leveled off with alachlor but consistently augmented with atrazine and fluometuron. The kinetic characterization showed that rimsulfuron or imazethapyr unchanged Vmax of all enzymes in vitro, however, Vmax of PEPC, PPDK and Rubisco were decreased in vivo. Nevertheless, atrazine or fluometuron substantially reduced Vmax of all enzymes while alachlor showed a reduction in this value of PEPC, MDH and Rubisco. Thus atrazine, fluometuron and, to a lower extent, alachlor reduced concentrations of all enzymes as well as rimsulfuron and imazethapyr for only Rubisco. On the contrary, Km values of all enzymes were progressively increased by all herbicides indicating that the different herbicides altered the structural integrity of all enzymes. These findings conclude that rimsulfuron or imazethapyr competitively inhibited MDH but revealed mixed inhibition to PEPC, PPDK and Rubisco. Atrazine or fluometuron revealed mixed inhibitions to all enzymes whereas alachlor seemed to be either a competitive inhibitor to PPDK or a mixed inhibitor to PEPC, MDH and Rubisco. 相似文献
33.
Mainar-Jaime RC Atashparvar N Chirino-Trejo M Rahn K 《The Canadian veterinary journal. La revue veterinaire canadienne》2008,49(8):793-796
A study on slaughter pigs from Saskatchewan detected Salmonella organisms in 12.5% and 5.2% of cecal content and ileocaecal lymph node samples, respectively. Cecal content prevalence was associated with larger farms and longer lairage periods. Antimicrobial resistance was detected in 41.5% of the isolates. Salmonella Enteritidis was the second most prevalent serotype. 相似文献
34.
Mainar-Jaime RC Atashparvar N Chirino-Trejo M Blasco JM 《Preventive veterinary medicine》2008,85(1-2):41-51
Large discrepancies are usually found when different ELISAs for the diagnosis of pig salmonellosis are compared. Thus, our main goal was to estimate the diagnostic accuracy through Bayesian approaches of two commercial assays (Svanovir™ “test A” and HerdCheck™ “test B”) for the detection of antibodies to Salmonella spp. in slaughter pigs. Previously, we estimated the agreement between both tests and their relative sensitivity (Se) and specificity (Sp) with respect to bacteriology on caecal content and ileocaecal lymph nodes. Test A, at a cut-off OD% ≥20%, indicated higher prevalence than test B (OD% ≥10%) (14.6% vs. 8.6%). Relative Se with respect to overall bacteriology was low (≈30%) and similar for both tests, but the relative Sp was significantly lower for test A compared to B (88% vs. 95%). Both tests failed to detect some pigs infected with Salmonella serogroups B and C1, which they were supposed to identify. In general, tests showed only fair-to-moderate agreement when they were compared (kappa: 0.41). In the Bayesian models, Se of test A varied between 63% and 77%, while Se of test B was 73%. Sp of A was always lower than that of test B (89% vs. 95%). The implications derived from the use of these imperfect serological tests will have to be accounted for in large-scale Salmonella-control programs. 相似文献
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36.
Roudkenar MH Bouzari S Kuwahara Y Roushandeh AM Baba T Oloomi M Fukumoto M 《Iranian Biomedical Journal》2008,12(1):1-6
BACKGROUND: Immunotoxins are comprised of both the cell targeting and the cell killing moieties. We previously established a new immunotoxin, i.e. Shiga toxin granulocyte macrophage-colony stimulating factor (StxA1-GM-CSF), comprises of catalytic domain of Stx, as a killing moiety and GM-CSF, as a cell targeting moiety. In this study, the ability of the immunotoxin to induce apoptosis and double strand breaks (DSB) on different cell lines was investigated. METHODS: The recombinant hybrid protein was expressed in bacterial expression system and purified with nickel-nitrilotriacetate acid resin. The K562 (erythroid leukemia) cell line and LS174 (colon carcinoma) were used in this study. The neutral comet assay was carried out for the detection of DSB and Hoechst staining was performed for apoptosis. RESULTS: StxA1-GM-CSF effectively induced apoptosis on K562 cell line and DNA Double Strand Break (DSB) were observed on colon cancer cell line treated with StxA1-GM-CSF. CONCLUSION: This novel action i.e. DNA damage might be a relevant mechanism of action for StxA1-GM-CSF that is designed to act as immunotoxin, although further investigation is required. 相似文献
37.
This study was designed to follow patients regarding to achieving control, identify disease exacerbations and discover relation between exacerbation and risk factors. In a cross sectional-analytic study, 400 asthmatic patients in the range of 2-14 years old who were visited at the specialized outpatient clinic of Tabriz University of Medical Sciences were divided and studied on the base of disease severity. At the end (at least one year treatment), patients were categorized based on level of disease control and one year after this stage, cases of exacerbation were identified and studied. By excluding patients with poor adherence, 342 patients continued treatment as intermittent, mild persistent, moderate persistent and severe persistent asthma (38, 235, 61 and 8 patients, respectively). After a period of one year treatment, the patients were divided as well controlled, partly controlled and uncontrolled (68, 30 and 2%, respectively). Cases of disease exacerbations were more if sinusitis, familial asthma history and poor adherence were present (p < 0.01, p < 0.001 and p < 0.05, respectively). There is meaningful association between poor adherence, sinusitis and positive family history of asthma with disease exacerbation. 相似文献
38.
Takeshi Hano Katsutoshi Ito Kumiko Kono Mana Ito Nobuyuki Ohkubo Kazuhiko Mochida 《Fish physiology and biochemistry》2017,43(1):137-152
This study was performed to unravel the mechanism of the beneficial action of taurine on marine teleost fish, red sea bream (Pagrus major), by analyzing the hepatic metabolism. Moreover, the ameliorative effects of the nutrient against cadmium toxicity and bioaccumulation were further evaluated. The fish were fed a diet containing 0 % (TAU0 %), 0.5 % (TAU0.5 %), or 5.0 % (TAU5.0 %) taurine for 40–55 days (d) and subjected to cadmium acute toxicity and bioaccumulation tests. Taurine deficiency in feed severely affected growth and the hepatic metabolic profiles of the fish, including a remarkable increase in myo-inositol, aspartate, and ß-alanine in the TAU0 % group, which indicates a complementary physiological response to taurine deficiency. For the acute toxicity test, fish were fed the test diets for 55 d and were then exposed to different dose of cadmium ranging from 0 to 5.6 mg/L for 96 h. Fish fed taurine had a higher tolerance to cadmium than those not fed taurine. For the bioaccumulation test, fish were fed the test diets for 40 d and then were chronically exposed to 0.2 mg/L of cadmium for 28 d followed by depuration for 21 d. Cadmium concentrations in the liver and muscle of fish fed TAU5.0 % were significantly lower than those of fish fed TAU0 % for the first 7 d of exposure and the first 7 d of elimination. Our findings suggest a possible mechanism for the beneficial role played by taurine and that the inclusion of taurine in fish aquaculture feed may reduce cadmium contamination of fish intended for human consumption. 相似文献
39.
Tahmasebi-Kohyani A Keyvanshokooh S Nematollahi A Mahmoudi N Pasha-Zanoosi H 《Fish physiology and biochemistry》2012,38(2):431-440
This experiment was conducted to examine the effect of dietary nucleotides (NT) on fish performance and acute stress response
on fingerling rainbow trout (23 g ± 0.01, mean weight ± SEM). Five experimental diets according to different levels of supplemented
nucleotides (0, 0.05, 0.1, 0.15, and 0.2%) were assayed on experimental fish for 8 weeks. Growth, hematological parameters
(hematocrit, hemoglobin, erythrocyte, lymphocyte, and neutrophil count), serum proteins (globulin, albumin), and plasma enzymatic
activity (alkaline phosphatase, ALP; aspartate transaminase, AST; lactate dehydrogenase, LDH; alanine transaminase, ALT) were
assayed. At the end of feeding trial, fish fed the control and 0.2% diets were subjected to handling and crowding stress.
Modulatory effects of nucleotides on acute stress response (cortisol and glucose) and plasma electrolytes (Na+, Cl−, K+, and Ca2+) were studied. The percentage of body weight gain (WG) and feed efficiency (FE) of fish were better when the fish were fed
0.15–0.2% diets. Fish fed the nucleotide-supplemented diets tended to have lower levels of serum enzymes including ALP, AST,
LDH, and ALT. Plasma cortisol levels of fish fed on 0.2% diet under handling and crowding stress were significantly lower
than fish fed the control diet at all post-stress time intervals. In our study, fish fed nucleotide-supplemented diet had
significantly lower concentrations of glucose compared to those fed the basal diet. The concentrations of sodium, chloride,
calcium, and potassium of fish fed the control diet were significantly lower than in fish fed nucleotide-supplemented diet.
Dietary nucleotides administration seems to promote growth and to enhance resistance against handling and crowding stress
in fingerling rainbow trout. 相似文献
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