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241.
Dong  Yuwei  Lu  Jun  Liu  Jinyi  Jalal  Abdul  Wang  Changquan 《Plant molecular biology》2020,102(4-5):417-430
Plant Molecular Biology - We genome-wide identified 28 JmjC domain-containing genes, further spatio-temporal expression profiling and genetic analysis defined them as epigenetic regulators in...  相似文献   
242.
A detailed effect of continuous exposure of Cd on an important pest of crops like Helicoverpa armigera is lacking in the current literature. The cadmium was provisioned at 1.25, 2.5 and 5 mg/kg in the artificial diet and fed to newly hatched larvae for at least three subsequent generations. The total developmental period and fecundity were severely affected with no larval hatching in treated insects. Total haemocyte count and differential haemocyte count (i.e., granulocytes and plasmatocytes) were decreased significantly compared to controls in treated insects. The antioxidant system (i.e., catalase, glucose-6-phosphate dehydrogenase, superoxide dismutase and peroxidase), and the two detoxifying agents glutathione-s-transferase showed increased activity compared to controls. The results of the acetylcholinesterase assay showed a decrease in activity. Increased rate of aspartate aminotransferase, alanine aminotransferase, uric acid and decreased rate of alkaline phosphatase and lactate dehydrogenase in the first generation but showing an increasing trend in next two generations. The acid phosphatase activity was increased in the first two generations but significantly reduced in the third generation. The discrepancy in all physiological activities corresponded with the histological study of midgut infrastructure. It is inferred from the obtained results that cadmium continuous exposure affects every system of any organism that may perform irreparable damages.  相似文献   
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244.
C-C Chemokine receptor 6 (CCR6), an important protein in inflammatory and immunological responses, has been previously reported to be associated with rheumatoid arthritis (RA). Therefore, in order to replicate these findings, a case-control study was conducted on 500 subjects (including 250 RA patients and 250 healthy controls) of Pakistani origin. The aim of this study was to determine the association of CCR6 rs3093024 variant with RA and identify its role in splicing events using bioinformatics tools. The clinical and demographic characteristics of the patients were collected using a well-designed questionnaire. The genotype frequencies of CCR6 rs3093024 variant were determined using tetra-primer ARMS-PCR (amplification of refractory mutation system-polymerase chain reaction) method. A significant difference was found between CCR6 rs3093024 genotype frequencies [P = 0.0016, χ2 = 12.915]. Similarly, a significant difference in the allele frequencies between RA patients and healthy controls was also observed [P = 0.0003 and OR (95% CI) = 0.63 (0.49–0.80)]. The stratification of patients showed that there was a significant increase in AA genotype against AG + GG in patients [P = 0.0014, OR (95% CI) = 2.0 (1.32–3.02)]. Furthermore, using bioinformatics analysis, it was found that CCR6 rs3093024 variant might create a potential splicing enhancer motif (SF2/ASF (IgM-BRCA1) with score of 77.92; Threshold 70.53), which might have important impact on the product of this gene. This study suggests that the A variant of CCR6 rs3093024 variant is significantly associated with RA-risk and its G variant is protective in Pakistani population but a multi-cohort large sized population study is needed to elucidate these results. Moreover, functional studies are needed to highlight the effects of this polymorphism on the function of CCR6 gene.  相似文献   
245.
Molecular Biology Reports - Acetaminophen overdose causes renal injury via oxidative stress and apoptosis induction. Carvacrol has several pharmacological properties such as antioxidant,...  相似文献   
246.
There is no study implying the effect of plant lectins on insect immune elements in both challenged and non‐challenged conditions with entomopathogenic agents. Lectins may bind to immune receptors on the surface of insect hemocytes, thus inducing or even disabling common immune functions including hemocyte counts, nodulation/encapsulation, phenoloxidase activity, and synthesis of antimicrobial peptides. In the present study, effect of Polygonum persicaria L. agglutinin (PPA) on immune responses of Helicoverpa armigera Hübner was investigated by feeding artificial diet treated to the larvae. Subsequently hemocyte count and expression of some immune‐related genes were considered for analyses. The two groups of larvae including control and PPA‐treated (1%) were divided into four subgroups of intact, Tween‐80 injected, latex‐bead injected and Beauveria bassiana‐injected. Except for intact larvae, the highest numbers of total and differential hemocyte counts were recorded 12 hr postinjection, however, the PPA‐fed larvae showed a significantly lower hemocyte counts compared to control. The number of nodules in PPA‐fed larvae was significantly lower than control, but the injected larvae of both control and PPA showed the highest nodulation 24 hr postinjection. Although the highest activity of phenoloxidase was observed 12 and 24 hr postinjection but its activity significantly decreased in PPA‐fed larvae compared to control. Gene expression of antimicrobial peptides including attacin, cecropin, and peptidoglycan receptor proteins were significantly decreased in artificial diet‐fed larvae containing PPA and then injected by B. bassiana spores and latex bead compared to control. These results clearly indicate adverse effects of PPA on immune responses in H. armigera.  相似文献   
247.
Methyl esters from vegetable oils have attracted a great deal of interest as substitute for petrodiesel to reduce dependence on imported petroleum and provide an alternate and sustainable source for fuel with more benign environmental properties. In the present study biodiesel was prepared from sunflower seed oil by transesterification by alkali-catalyzed methanolysis. The fuel properties of sunflower oil biodiesel were determined and discussed in the light of ASTM D6751 standards for biodiesel. The sunflower oil biodiesel was chemically characterized with analytical techniques like FT-IR, and NMR (1H and 13C). The chemical composition of sunflower oil biodiesel was determined by GC–MS. Various fatty acid methyl esters (FAMEs) were identified by retention time data and verified by mass fragmentation patterns. The percentage conversion of triglycerides to the corresponding methyl esters determined by 1H NMR was 87.33% which was quite in good agreement with the practically observed yield of 85.1%.  相似文献   
248.
Journal of Plant Growth Regulation - Germination is a crucial event in plant lifecycle mediated by a complex hormonal crosstalk. In this study, we revealed an antagonistic interaction between...  相似文献   
249.
Capecitabine is a chemotherapeutic agent used for the treatment of patients with metastatic cancers. This study aimed at determining the drug capecitabine in a simple chemiluminescence (CL) system of acidic potassium permanganate using the stopped‐flow injection technique. Statistical methods were used to detect optimum conditions. The method showed two linear calibration ranges from 6.7 × 10?6 to 6.7 × 10?5 mol L?1 and from 6.7 × 10?5 to 2.7 × 10?3 mol L?1 with a detection limit of 1.5 × 10?6 mol L?1. Chitosan‐modified magnetic nanoparticles were studied in the drug‐delivery experiments. According to the pH sensitivity of chitosan and low pH values in tumour cells, the chitosan‐coated magnetic nanoparticles could provide a good targeting drug‐delivery system to tumour sites. To evaluate the applicability of the method, the capecitabine‐loaded magnetic chitosan nanoparticles were synthesized with two different cross‐linkers; loading and releasing rates of the drug were investigated using the proposed CL method and an ultraviolet–visible light spectrophotometric method (absorption at 305 nm). The results showed a good correlation between the two methods, and it was found that the synthesized chitosan‐modified magnetic nanoparticles could be used for pH‐dependent release of capecitabine in cancer cells. Moreover, determination of capecitabine in tablets and synthetic samples was performed.  相似文献   
250.
Background and aimType 2 diabetes (T2D) is a complex polygenic disease with unclear mechanisms. Clinical studies on the association of vitamin A with T2D in humans are still controversial. Herein, we aimed to investigate the plasma levels of vitamin A, predictor factors, and its correlations with clinical phenotypes in Emirati population. The effect of glucose-and lipid-lowering medications on vitamin A levels was also studied.MethodsA cross-sectional cohort comprised 158 T2D-subjects and 90 healthy controls were recruited from the United Arab Emirates National Diabetes Study (UAEDIAB). All anthropometric, clinical, and biomedical measurements were collected. Plasma levels of vitamin A were determined using ELISA assay.ResultsLevels of vitamin A were significantly lower in T2D-subjects compared to healthy control (p < 0.01). Vitamin A levels were unaffected by gender base and inversely correlated with age, fasting blood glucose (FBG), glycated hemoglobin (HbA1c), waist circumference, triglycerides, and body mass index (BMI). Regression analysis revealed that HbA1c and age are predictors for vitamin A. Intake of glucose- or lipid-lowering medications showed no effect on vitamin A levels.ConclusionHbA1c and age are predictors for low levels of vitamin A among Emirati-T2D subjects. No influence of glucose and lipid-lowering medications on the plasma levels of vitamin A.  相似文献   
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