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991.
Deficiencies of essential vitamins, iron (Fe), and zinc (Zn) affect over one-half of the world’s population. A significant progress has been made to control micronutrient deficiencies through supplementation, but new approaches are needed, especially to reach the rural poor. Agronomic biofortification of pulses with Zn, Fe, and boron (B) offers a pragmatic solution to combat hidden hunger instead of food fortification and supplementation. Moreover, it also has positive effects on crop production as well. Therefore, we conducted three separate field experiments for two consecutive years to evaluate the impact of soil and foliar application of the aforementioned nutrients on the yield and seed biofortification of mungbean. Soil application of Zn at 0, 4.125, 8.25, Fe at 0, 2.5, 5.0 and B at 0, 0.55, 1.1 kg ha−1 was done in the first, second and third experiment, respectively. Foliar application in these experiments was done at 0.3% Zn, 0.2% Fe and 0.1% B respectively one week after flowering initiation. Data revealed that soil-applied Zn, Fe and B at 8.25, 5.0 and 1.1 kg ha−1, respectively, enhanced the grain yield of mungbean; however, this increase in yield was statistically similar to that recorded with Zn, Fe and B at 4.125, 2.5 and 0.55 kg ha−1, respectively. Foliar application of these nutrients at flower initiation significantly enhanced the Zn contents by 28% and 31%, Fe contents by 80% and 78%, while B contents by 98% and 116% over control during 2019 and 2020, respectively. It was concluded from the results that soil application of Zn, Fe, and B enhanced the yield performance of mungbean; while significant improvements in seed Zn, Fe, and B contents were recorded with foliar application of these nutrients.  相似文献   
992.
Salinity, a severe environmental factor, has limited the growth and productivity of crops. Many compounds have been applied to minimize the harmful effects of salt stress on plant growth. An experiment was conducted to investigate the interactive effects of exogenous ascorbic acid (AsA) and gibberellic acid (GA3) on common bean (Phaseolus vulgaris L. cv. Naz) seedlings under salt stress. The changes of growth parameters, photosynthetic and non-photosynthetic pigments and potassium content showed that the addition of 1 mM AsA and/or 0.05 mM GA3 considerably decreased the oxidative damage in common bean plants treated with 200 mM NaCl. The NaCl-stressed seedlings exposed to AsA or GA3, specifically in their combination, exhibited an improvement in sodium accumulation in both roots and shoots, as compared to NaCl-treated plants. NaCl treatment increased hydrogen peroxide (H2O2) content and lipid peroxidation indicated by accumulation of malondialdehyde (MDA), whereas the interaction of AsA with GA3 decreased the amounts of MDA and H2O2. In the meantime, interactive effect of these substances enhanced protein content and the activity of the antioxidant enzyme, guaiacol peroxidase, in common bean plants under salt stress. It was concluded that synergistic interaction between AsA and GA3 could alleviate the adverse effects of salinity on P. vulgaris seedlings.  相似文献   
993.
Pharmacists are the custodians of drugs; hence their education, training, behaviors and experiences would affect the future use of drugs at community and hospital pharmacies. Therefore, we aimed at evaluating the self-prescribing antibiotic trends, knowledge and attitudes among pharmacy and non-pharmacy students. We found that pharmacy students had higher risks of experiencing URIs related symptoms such as cough (RR; 1.7, p = 0.002), allergy (RR; 2.07, p = 0.03) and running nose (RR; 3.17, p<0.005), compared to non-pharmacy students -resulting in higher probabilities of selecting cough syrups (OR; 2.3, p<0.005), anti-histamines (OR; 1.8, p = 0.036) and anti-inflammatory/anti-pyretic (OR; 2.4, p<0.005) drugs. Likewise, bachelor’s degree pupils (OR; 2, p = 0.045), urban area residents (OR; 2.44; p = 0.002) and pharmacy students (OR; 2.9, p<0.005) exhibited higher propensities of antibiotic self-use–notable classes include, b-lactams (45.9%) followed by macrolides (26.5%) and augmentin (28.94%), respectively. Surprisingly, pharmacy and non-pharmacy students had higher odds of using antibiotics in common cold (OR; 3.2, p<0.005) and pain (OR; 2.37, p = 0.015), respectively. Unlike non-pharmacy students, pharmacy students were likely to select alternative therapy, such as Joshanda (OR; 2.22, p = 0.011) and were well acquainted with antibiotic hazards, with 77% reduction in risk of antibiotics re-use. In conclusion, university students exhibited antibiotic self-prescribing trends in conditions that does not warrant their use, thus are irrational users. The pharmacy education confers very little benefit to rational self-prescribing practices among students, while non-pharmacy students are more vulnerable to repeated antibiotic usage. Thus, the educational and training modules should be designed for university students to disseminate targeted information regarding the potential hazards of antibiotic self-use and importance of consultation with qualified and registered medical doctor/pharmacist before starting with antibiotics.  相似文献   
994.
The spatial patterning of proteins in bacteria plays an important role in many processes, from cell division to chemotaxis. In the asymmetrically dividing bacteria Caulobacter crescentus, a scaffolding protein, PopZ, localizes to both poles and aids the differential patterning of proteins between mother and daughter cells during division. Polar patterning of misfolded proteins in Escherichia coli has also been shown, and likely plays an important role in cellular ageing. Recent experiments on both of the above systems suggest that the presence of chromosome free regions along with protein multimerization may be a mechanism for driving the polar localization of proteins. We have developed a simple physical model for protein localization using only these two driving mechanisms. Our model reproduces all the observed patterns of PopZ and misfolded protein localization--from diffuse, unipolar, and bipolar patterns and can also account for the observed patterns in a variety of mutants. The model also suggests new experiments to further test the role of the chromosome in driving protein patterning, and whether such a mechanism is responsible for helping to drive the differentiation of the cell poles.  相似文献   
995.
A case–control association study on 229 Myocardial Infarction (MI) patients and 217 healthy controls was carried out to determine the role of tissue-plasminogen activator (t-PA) (Alu-repeat insertion (I)/deletion (D)) and plasminogen activator inhibitor (PAI-1) (4G/5G insertion/deletion) polymorphisms with MI in the Pakistani population. In MI patients the genotype distribution of the PAI-1 gene was not found to be different when compared with the unaffected controls (P > 0.05, χ2 = 1.03). The risk allele 4G was also not associated with MI (P > 0.05, χ2 = 0.46, odds ratio (OR) = 1.1 (95% confidence interval (CI) = 0.84–1.43), P > 0.05). Similarly, the genotype frequencies of t-PA I/I, I/D and D/D were not different from the unaffected controls (P > 0.05, χ2 = 1.60), and the risk allele “I” was not found to be associated with MI (P > 0.05, χ2 = 1.35, OR = 0.86 (95% CI = 0.66–1.11), P > 0.05). However, when the data were distributed along the lines of gender a significant association of the 4G/4G PAI-1 genotype was observed with only the female MI patients (P < 0.05, z-test = 2.21). When the combined genotypes of both the polymorphisms were analyzed, a significant association of MI was observed with the homozygous DD/4G4G genotype (P < 0.01, z-test = 2.61), which was specifically because of the female samples (P = 0.01, z-test = 2.53). In addition smoking (P < 0.001, χ2 = 13.52, OR = 3.45 (95% CI = 1.77–6.94)), diabetes (P < 0.001, χ2 = 22.45, OR = 8.89 (95% CI = 2.96–29.95)), hypertension (OR = 7.76 (95% CI = 2.88–22.68), P < 0.001) family history (P < 0.001, χ2 = 13.72, OR = 3.7 (95% CI = 1.71–8.18)) and lower HDL levels (P < 0.05) were found to be significantly associated with the disease. In conclusion the PAI-1 gene polymorphism was found to have a gender specific role in the female MI patients.  相似文献   
996.
Formation of estrogen metabolites that react with DNA is thought to be a mechanism of cancer initiation by estrogens. The estrogens estrone (E1) and estradiol (E2) can form catechol estrogen (CE) metabolites, catechol estrogen quinones [E1(E2)-3,4-Q], which react with DNA to form predominantly depurinating adducts. This may lead to mutations that initiate cancer. Catechol-O-methyltransferase (COMT) catalyzes an inactivation (protective) pathway for CE. This study investigated the effect of inhibiting COMT activity on the levels of depurinating 4-OHE1(E2)-1-N3Ade and 4-OHE1(E2)-1-N7Gua adducts in human breast epithelial cells. MCF-10F cells were treated with TCDD, a cytochrome P450 inducer, then with E2 and Ro41-0960, a COMT inhibitor. Estrogen metabolites and depurinating DNA adducts in culture medium were analyzed by HPLC with electrochemical detection. Pre-treatment of cells with TCDD increased E2 metabolism to 4-OHE1(E2) and 4-OCH3E1(E2). Inclusion of Ro41-0960 and E2 in the medium blocked formation of methoxy CE, and depurinating adducts were observed. With Ro41-0960, more adducts were detected in MCF-10F cells exposed to 1 μM E2, whereas without the inhibitor, no increases in adducts were detected with E2 ≤ 10 μM. We conclude that low COMT activity and increased formation of depurinating adducts can be critical factors leading to initiation of breast cancer.  相似文献   
997.
Incidence of Malignant Melanoma has become the 5th in the UK. To date, the major anticancer therapeutics include cell therapy, immunotherapy, gene therapy and nanotechnology-based strategies. Recently, extracellular vesicles, especially exosomes, have been highlighted for their therapeutic benefits in numerous chronic diseases. Exosomes display multifunctional properties, including inhibition of cancer cell proliferation and initiation of apoptosis. In the present in vitro study, the antitumour effect of cord blood stem cell (CBSC)-derived exosomes was confirmed by the CCK-8 assay (p < 0.05) on CHL-1 melanoma cells and improve the repair mechanism on lymphocytes from melanoma patients. Importantly, no significant effect was observed in healthy lymphocytes when treated with the exosome concentrations at 24, 48 and 72 h. Comet assay results (OTM and %Tail DNA) demonstrated that the optimal exosome concentration showed a significant impact (p < 0.05) in lymphocytes from melanoma patients whilst causing no significant DNA damage in lymphocytes of healthy volunteers was 300 μg/ml. Similarly, the Comet assay results depicted significant DNA damage in a melanoma cell line (CHL-1 cells) treated with CBSC-derived exosomes, both the cytotoxicity of CHL-1 cells treated with CBSC-derived exosomes exhibited a significant time-dependent decrease in cell survival. Sequencing analysis of CBSC exosomes showed the presence of the let-7 family of miRNAs, including let-7a-5p, let-7b-5p, let-7c-5p, let-7d-3p, let-7d-5p and two novel miRNAs. The potency of CBSC exosomes in inhibiting cancer progression in lymphocytes from melanoma patients and CHL-1 cells whilst causing no harm to the healthy lymphocytes makes it a potential candidate as an anticancer therapy.  相似文献   
998.
999.
The clinical link among diabetes, obesity, and thyroid dysfunction is of interest. Hence, medical records of 601 patients with diabetes, obesity, and thyroid dysfunctions at the Abha Specialist Center and Military Diabetic Endocrine Center we used in this analysis. Approximately 28% of diabetic patients had thyroid dysfunction, and 12.4% were vitamin D deficient. The patients with thyroid dysfunction had significantly elevated triglyceride levels compared to the patients without thyroid dysfunction (173.6 vs. 128. p=0.009). Vitamin D deficient obese patients were significantly younger (33.99±10.69 vs. 43.68±14.42; p<0.001) and had significantly lower levels of HbA1c (5.73±1.16 vs. 6.83±2.08; p=0.014) and lower systolic BP (120.26±11.75 vs. 124.58±13.63; p=0.049) than non-vitamin D deficient obese patients. Vitamin D deficient thyroid patients had significantly lower diastolic BP (71.4±9.9 vs. 74.9±9.7; p=0.040) and higher HbA1c (8.7±3.6 vs. 6.4±1.7; p=0.003) in comparison to non-vitamin D deficient thyroid patients. Hence, analysis of metabolic disorders in these patients will help combat complications in these cases.  相似文献   
1000.
The hindered rotations of acetone were studied density functional theory (B3LYP) and second order Møller-Plesset approaches using 6-31G** and 6-311G** basis sets. One of the CH3 groups of acetone with fixed heavy atoms was rotated from 0.0 to 120°, and CCH angles were scanned from 90.3 to 130.3° to cover the potential energy surface of interest; a circular valley was obtained with the deepest potential value at a CCH angle equal to 109.3°. Potential energy profiles were then calculated by assuming that the molecular geometry could relax during rotation (i.e., each value of the torsion angle of the molecular geometry was optimized). Next, the two methyl groups were both rotated clockwise, and then one was rotated clockwise and the other counterclockwise. Using the variation method, and utilizing the first 20 harmonic oscillator wave functions, the energy levels, relative transition moment and relative transition intensities of the component of the hindered rotation ν2 (125.16 cm?1) were computed in a one-dimensional Schrodinger equation. The first three energy levels were almost degenerate; the next three were opened up, and the seventh energy level appeared above the level where tunneling can occur.  相似文献   
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