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Vinod?K.?SharmaEmail author Chandresh?Chandel Raj?Kumar S.?S.?Dey Chander?Parkash Reeta?Bhatia M.?Mawliya 《Proceedings of the National Academy of Sciences, India. Section B.》2018,88(2):451-457
The present study reports the quantification of changes in the contents of plant pigments and ascorbic acid as influenced by the planting time and fruit picking stages in sweet pepper. The crop was planted on five different dates at 10 days interval in randomized block design under open field conditions in temperate area to quantify the changes which took place in the contents of plant pigments and ascorbic acid in green and red fruits. The results showed that the planting time and fruit picking stage had significant (p ≤ 0.05) influence on plant pigments and ascorbic acid contents in sweet pepper. The last week of May was observed as the optimal planting time when fruits exhibited higher contents of lycopene, β-carotene and ascorbic acid. The red fruit picking stage had significantly higher concentration of these phytonutrients than the green picking stage. In order to pick-up fruits at right stage and time with high plant pigments and ascorbic acid contents, these results would help meet out the increasing demand of sweet pepper quality fruits. 相似文献
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In the present investigation we have prepared and characterized curcumin (CN)-containing chitosan nanoparticles (CS-NPs) coated with Eudragit FS 30D for colon-specific drug delivery for treatment of ulcerative colitis. Methods: CS-NPs were prepared by ionic gelation using tripolyphosphate. To specify pH sensitive delivery, CS–CN-NPs were coated with Eudragit FS 30D by using a solvent evaporation method. Different process parameters were evaluated, and the optimized formulation was characterized by particle size, size distribution, zeta potential and encapsulation efficiency before lyophilization. The lyophilized product was further subjected to Fourier-transform infrared spectroscopy, and particle morphology and in vitro drug release in different media were studied. Results: the kinetics of in vitro drug release from the CS–CN-NPs revealed sustained release behaviour of the developed carriers. In vivo biodistribution study by gamma-scintigraphy showed good accumulation of the developed nanocarriers in the colonic region. Conclusion: sustained and pH stimulated delivery of CN to the colon was successfully attained via coating of CS-NPs with Eudragit FS 30D to circumvent poor absorption and availability of CN.In the present investigation we have prepared and characterized curcumin (CN)-containing chitosan nanoparticles (CS-NPs) coated with Eudragit FS 30D for colon-specific drug delivery for treatment of ulcerative colitis. 相似文献
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Kalaiyarasan Thiyagarajan Vijay K. Bharti Shruti Tyagi Pankaj K. Tyagi Anami Ahuja Krishna Kumar Tilak Raj Bhuvnesh Kumar 《RSC advances》2018,8(41):23213
For nearly a decade, silver nanoparticles (AgNPs) have been the most prevalent commercial nanomaterials products widely used in different biomedical applications due to their broad-spectrum antimicrobial activity. However, their poor long-term stability in different environments, namely, pH, ionic strength, and temperature, and cytotoxicity toward mammalian cells has restricted their more extensive applications. Hence, there is urgent need to develop highly biocompatible, non-toxic, and stable silver nanoparticles for wide-ranging environments and applications. In the present study, a simple, sustainable, cost-effective and green method has been developed to prepare highly stable aqueous colloidal silver nanoparticles (AgNPs-EW) using the ovalbumin, ovotransferrin, and ovomucoid of egg-white as reducing and capping agents accomplished under the irradiation of direct sunlight. Then, we evaluated the effects of freezing–drying (lyophilization) and freeze–thaw cycles on the stability of AgNPs-EW in aqueous solution under visual inspection, transmission electron microscopy, and absorbance spectroscopy. In addition, we studied the antibacterial activity against Salmonella typhimurium and Escherichia coli, carried out biocompatibility studies on chicken blood, and tested acute, chronic toxicity in Drosophila melanogaster. The results suggest that AgNPs-EW did not aggregate upon freeze-thawing and lyophilization, thus exhibiting remarkable stability. The antibacterial activity results showed that the AgNPs-EW had the highest antibacterial activity, and the minimum inhibitory concentration (MIC) of AgNPs-EW for E. Coli and S. typhimurium were 4 and 6 μg ml−1, respectively. The biocompatibility study revealed that the AgNPs-EW did not induce any hemolytic effect or structural damage to the cell membranes of chicken erythrocytes up to a concentration of 12 μg ml−1. Similarly, no acute and chronic toxicity was observed on melanization, fecundity, hatchability, viability, and the duration of development in the 1st generation of Drosophila melanogaster at the concentration range of 10 mg L−1 to 100 mg L−1 of AgNPs-EW, and all the flies completed their full developmental cycle. Therefore, the present study successfully demonstrated the green and sustainable preparation of non-toxic AgNPs-EW having good biocompatibility, enhanced colloidal stability, and antibacterial activity. Hence, the synthesized AgNPs-EW could be used for the development of an antimicrobial formulation for controlling microbial infection.For nearly a decade, silver nanoparticles (AgNPs) have been the most prevalent commercial nanomaterials products widely used in different biomedical applications due to their broad-spectrum antimicrobial activity. 相似文献
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Philippe Généreux Nicolo Piazza Maria C. Alu Tamim Nazif Rebecca T. Hahn Philippe Pibarot Jeroen J. Bax Jonathon A. Leipsic Philipp Blanke Eugene H. Blackstone Matthew T. Finn Samir Kapadia Axel Linke Michael J. Mack Raj Makkar Roxana Mehran Jeffrey J. Popma Martin B. Leon 《Journal of the American College of Cardiology》2021,77(21):2717-2746
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Norm R.C. Campbell Pedro Ordunez Gloria Giraldo Yenny A. Rodriguez Morales Cintia Lombardi Taskeen Khan Raj Padwal Ross T. Tsuyuki Cherian Varghese 《The Canadian journal of cardiology》2021,37(5):744-755
Globally, cardiovascular diseases (CVDs) are the leading cause of death. Viewed as a threat to the global economy, the United Nations included reducing noncommunicable diseases, including CVDs, in the 2030 sustainable development goals, and the World Health Assembly agreed to a target to reduce noncommunicable diseases 25% by the year 2025. In response, the World Health Organisation led the development of HEARTS, a technical package to guide governments in strengthening primary care to reduce CVDs. HEARTS recommends a public health and health system approach to introduce highly simplified interventions done systematically at a primary health care level and has a focus on hypertension as a clinical entry point. The HEARTS modules include healthy lifestyle counselling, evidence-based treatment protocols, access to essential medicines and technology, CVD risk-based management, team-based care, systems for monitoring, and an implementation guide. There are early positive global experiences in implementing HEARTS. Led by the Pan American Health Organisation, many national governments in the Americas are adopting HEARTS and have shown early success. Unfortunately, in Canada hypertension control is declining in women since 2010-2011 and the dramatic reductions in rates of CVD seen before 2010 have flattened when age adjusted and increased for rates that are not age adjusted, and there are marked increases in absolute numbers of Canadians with adverse CVD outcomes. Several steps that Canada could take to enhance hypertension control are outlined, the core of which is to implement a strong governmental nongovernmental collaborative strategy to prevent and control CVDs, focusing on HEARTS. 相似文献
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