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21.
Abstract

Biochar is considered a novel soil amendment for cadmium (Cd) stabilization in contaminated soils. A pot experiment was conducted to examine the efficiency of wheat straw and sugarcane bagasse induced biochar on Cd mobility in soil and its bioavailability to spinach in contaminated soil. Soil pH, Cd contents in plant tissues and microbial biomass were examined. Results showed that Cd was significantly decreased by 30.95% and 20.83% with wheat straw and sugarcane bagasse biochar at 2% application rate respectively, relative to the control. Similarly, Cd contents were decreased in plants shoots by 15.41 and 14.33%, while in roots by 48.3 and 35.54%, when wheat straw and sugarcane biochar were added at 2% application rate respectively. Moreover, soil microbial biomass was significantly increased with the application of all biochar types and their applications rates. Finally, wheat straw biochar at 2% application rate can be considered as an effective approach for Cd stabilization in contaminated soils.  相似文献   
22.
Doxorubicin‐induced renal toxicity overshadows its anticancer effectiveness. This study is aimed at assessing the possible modulator effects of meloxicam, a cyclooxigenase‐2 inhibitor, on doxorubicin‐induced nephrotoxicity in mice and exploring some of the modulator mechanisms. Forty male mice were divided for treatment, for 2 weeks, with saline, meloxicam (daily), doxorubicin (twice/week), or both meloxicam and doxorubicin. Doxorubicin induced a significant increase in relative kidney weight to body weight, kidney lipid perooxidation, plasma levels of interleukin‐6 and tumor necrosis factor‐α, kidney caspase‐3 activity, and kidney prostaglandin E2 (PGE2) content. Doxorubicin disturbed kidney histology, abrogated renal function tests (serum creatinine, uric acid, and blood urea nitrogen), induced a significant decrease in antioxidant enzyme activities (superoxide dismutase, glutathione peroxidase, and catalase) and reduced glutathione (GSH) content. The administration of meloxicam with doxorubicin mitigated all doxorubicin‐disturbed parameters. Meloxicam ameliorated doxorubicin‐induced renal injury via inhibition of inflammatory PGE2, inflammatory cytokines, caspase‐3 activity, antioxidant effect, and free radical scavenging activity.  相似文献   
23.
Functional & Integrative Genomics - MicroRNAs are small, non-coding RNAs that are responsible for regulation of gene expression during plant growth and development. Although there are many...  相似文献   
24.

Objective

Rheumatoid arthritis (RA) is one of the most prevalent chronic autoimmune diseases; it typically involves the hands, wrists, ankles, and eventually all joints. Some studies have reported that zinc serum levels are lower in patients with RA than in healthy individuals.

Materials and Methods

Seventy-nine patients with RAwere selected. The patients were all less than 75 years old and were diagnosed by a rheumatologist. Serum zinc levels were measured using the flame photometry method with a blood sample of 5 mL. The relationship between the average serum zinc level and disease activity was analyzed based on the DAS28 scoring scale for different RA groups. The significance threshold was set at p<0.05. Data analyses were implemented in SPSS 22.0.

Results

There was a significant inverse relationship between the serum zinc levels and disease activity. Chi-square tests were used to compare zinc serum levels with respect to disease activity. There were significant differences in zinc levels among three groups of patients with different levels of disease severity, such that disease activity increased as the serum zinc level decreased (p<0.001).

Conclusion

There was a significant inverse relationship between the serum zinc level and RA activity based on the DAS28 score. Therefore, it is recommended that mineral deficiencies should be addressed by optimizing the zinc supply along with other standard medications in order to reduce RA activity.
  相似文献   
25.
Insect-resistant transgenic cotton has been commercialized for two decades. Most of the introduced cultivars express Bt gene(s) constitutively under the control of 35S promoter in whole-plant tissues. However, there have been other promoters considered by researchers to confine the toxin expression to targeted organ and tissues. We developed a triple-gene construct including GNA, cry1Ac and cp4 epsps genes. We attempted to confine cry1Ac expression to insect biting sites by cloning it to downstream of a wound-inducible promoter isolated from Asparagus officinalis (AoPR1). Moreover, to broaden the range of resistance, GNA was driven by the 35S promoter to target the sap-sucking insects like aphids which impose large losses in cotton production. To select the transformants in selection medium and for glyphosate tolerance, GNA and cry1Ac genes were accompanied with cp4 epsps gene. Two binary vectors harboring desired genes were constructed and utilized in the study (pGTGNAoC1AC and pGTGN35C1AC). Transformation of cultivar GSN-12 was carried out by employing Agrobacterium tumefaciens strain EHA105. Plantlets were primarily screened under glyphosate (N-phosphonomethyl glycine) selection pressure and subsequently subjected to molecular and biotoxicity assays. Introduction of cry1Ac and GNA to cotton plant conferred resistance to Spodoptera littoralis and Aphis gossypii Glover. Restriction of cry1Ac toxin protein to insect biting sites along with a plant lectin attributes significantly to insect pest management strategies.  相似文献   
26.
BACKGROUND: An imbalance between zinc and copper metabolism has been reported to predispose to coronary artery disease (CAD) in Western populations, but there are little data for other racial groups. We have therefore investigated the association between serum copper and zinc, and CAD in Iranian subjects undergoing coronary angiography. METHODS: Serum copper, zinc, fasting lipid profile, and blood glucose levels were measured in 114 patients (67 male and 47 female) undergoing routine coronary angiogram. Anthropometric features including blood pressure were determined using standard procedures. Demographic characteristics, including menopausal status and smoking habit, were assessed by questionnaire. RESULTS: Male patients had lower serum copper (p<0.05), lower serum zinc (p<0.05), and higher serum zinc/copper ratio (p<0.05) than females. Serum copper and zinc concentrations were significantly lower in the subjects with angiographically defined CAD than those patients with a normal angiogram, although the zinc/copper ratio was higher in these patients (p<0.001). Serum copper (r=-0.303, p<0.001) and zinc (r=-0.250, p<0.01) concentrations were both inversely related to age, and copper was positively associated with fasting serum triglycerides (r=0.188, p<0.05). CONCLUSION: Serum copper and zinc concentrations were significantly lower in Iranian patients with abnormal versus those with a normal angiogram. However, the zinc/copper ratio was higher in patients with CAD compared to subjects without CAD. Serum zinc and copper concentrations appear to be influenced by several physiological factors including age and gender.  相似文献   
27.
To assess comparative losses of Trianthema portulacastrum (HP) relative to other weeds, the experiment was set during consecutive summer seasons 2018 and 2019 at the Research Farm MNS-University of Agriculture, Multan, Pakistan. Experiment consisted three replications which were laid out under randomized complete block design. Experiment consisted of ten treatments viz: weeds free (whole season), HP free till 20 Days after emergence (DAE), HP free till 40 DAE, HP free till 60 DAE, all weeds free 20 DAE, all weeds free 40 DAE, all weeds free 60 DAE, weedy check (all weeds), weedy check except HP and weedy check containing only HP. During 2018 in all weeds weedy check, maximum HP relative density (33.33%) was observed while in 2019, plot where weeds were controlled from growing till 20 DAE showed (80%) relative density at 30 DAE. HP maximum frequency (66.67%, 77.78%) and relative frequency (66%, 100%) was recorded at 45 DAE in plots where HP was kept controlled till 20 DAE and all weeds kept controlled till 20 DAE, respectively. Maximum number of grains per cob (738, 700.68), 1000 grain weight (306.66, 271.51 g) and grain yield (6150, 8015 kg hec-1) were recorded in plots which were kept all weed free till 60 DAE. As the competition period of weeds increased over 40 DAE, it substantially reduced yield of maize. Keeping the plots HP free till 40 DAE in the maize fields with HP as the major dominating weed, likely increase in maize grain yield is up to 30% compared to the fields where HP left un attended throughout the growing season. However, if maize field is infested with a mix of weeds with more than one dominating weeds including HP, compared to weedy situation the whole season, 30% higher grain yield can be obtained if all weeds are kept controlled till 40 DAE. Hence it can be concluded that whether the farmers face heavy HP infestation only or the mix of weeds as dominating weeds, in either case farmer should control weeds within first 40 days in maize field for better grain yield.  相似文献   
28.
The present study was aimed to address the possible evaluation of Azadirachta indica (neem) leaf-supplemented diets on innate immune response in Asian seabass, Lates calcarifer fingerlings against Vibrio harveyi infection. Fish were fed for two weeks diets containing six graded levels of neem leaf at 0 g, 1 g, 2 g, 3 g, 4 g and 5 g per kg feed. Fish fed neem leaf-supplemented diet displayed significant differences (p < 0.05) in weight gain, specific growth rate (SGR) and feed conversion ratio (FCR) compared to the control group fed without neem leaf-supplemented diet. Various innate immune parameters were examined pre-challenge and post-challenge. Fish was injected intraperitoneally with a lethal dose of V. harveyi containing 108 cells mL?1. Supplementation of neem leaf diet significantly increased phagocytic activity, superoxide anion production, serum lysozyme, serum bactericidal activity, serum anti-protease activity throughout the experimental period when compared with the control group. Dietary doses of neem leaf diet significantly influenced the immune parameters, haematological parameters and blood biochemical indices of treated fish. The results suggested that fish fed neem leaf-supplemented diet improved the immune system and increased survival rate in L. calcarifer fingerlings against V. harveyi infection.  相似文献   
29.
30.
Spider venoms are neurotoxin proteins that can kill insects. Spider toxin Hvt gene was cloned under two phloem specific RSs1 and RolC promoters, transformed into tobacco plants through Agrobacterium-mediated transformation and tested against Heliothis armigera larvae. Transgenic plants were confirmed through PCR. First instar larvae of H. armigera were released on detached leaves of transformed and non-transformed plants. Insect bioassays showed 93–100% mortality of H. armigera larvae within 72 h on the leaves of transgenic plants while all larvae survived and continued feeding on detached leaves from non-transformed control plants. The Hvt gene expressing under phloem specific RSs1 and RolC promoters could therefore be used for developing H. armigera-resistant, genetically-modified crops.  相似文献   
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