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101.
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   
102.
103.
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   
104.
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   
105.
106.
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   
107.
108.
In the normal adult brain, glucose provides 90% of the energy requirements as well as substrate for nucleic acid and lipid synthesis. In the present study, effects of ethanol on glucose transporters (GLUT) and glucose utilization were examined in rat brain. Male Sprague-Dawley rats weighing 250-300 gms were given either ethanol 3 gm/kg BW or saline IP 4 hrs prior to the animal sacrifice and removal of the cerebral cortical tissue. The cortical plasma membranes analyzed by cytochalasin B binding assay showed a decrease in GLUT number but not in GLUT affinity in the ethanol treated rats as compared to the control rats. The estimated Ro values were 70 ± 8.9 Vs 91 ± 8.9 pmoles/mg protein (p < 0.05 N=4) and the estimated Kd values were 0.37 ± 0.03 and 0.28 ± 0.05 M (p: NS) in ethanol and control experiments respectively. Immunoblots of purified cerebral plasma membranes and low density microsomal fraction showed 17% and 71% decrease for GLUT1 and 54% and 21% (p<0.05 or less; n=6) for GLUT3 respectively in ethanol treated rats than in control animals. Immunofluoresence studies also showed reduction of GLUT1 immunoreactively in choroid plexus and cortical microvessels of ethanol treated rats as compared to control rats. The effect of ethanol on regional cerebral metabolic rates for glucose (CMRGle) was studied using [6-14C] glucose and showed statistically insignificant decrease in brain glucose utilization. These data suggest that ethanol invivo decrease GLUT number and protein content in rat cerebral cortex  相似文献   
109.
Hepatitis E virus (HEV) is an emerging cause of acute hepatitis in Europe, particularly in southern France, and HEV is a new causative agent of chronic hepatitis and cirrhosis in immunocompromised patients. However, the data regarding HEV infection after kidney transplantation are still scarce with respect to the clinical issues that have been raised, and no study has specifically focused on kidney transplant recipients. This study described the clinical features and outcomes of HEV infections in a cohort of kidney transplant recipients living in southeastern France. The epidemiological, clinical, and virological characteristics of HEV infections diagnosed by PCR over a 53‐month period were retrospectively analyzed in a cohort of 1,350 kidney transplant recipients monitored at the Marseille University Hospital. Sixteen HEV infections were diagnosed, all of which were autochthonous and involved genotype 3 viruses (HEV‐3). Chronic infections occurred in 80% of these patients and resolved in half of the cases after a median time of 39 months. The rate of HEV clearance was 54% after a decrease in the dose of immunosuppressants. One patient developed liver cirrhosis 14 months after infection and experienced acute rejection after a decrease in the dose of immunosuppressants. Autochthonous HEV‐3 infections in kidney transplant recipients progress to chronicity in most cases and might be complicated by early liver cirrhosis. Chronic HEV infection can resolve following the reduction of immunosuppressive therapy, but ribavirin may be required if reduction of the immunosuppressant dose is not associated with HEV clearance or is inappropriate for the patient management. J. Med. Virol. 85:462–471, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
110.
The complete genome of the Japanese encephalitis virus (JEV) strain JEV/eq/India/H225/2009(H225), isolated from an infected horse in India, was sequenced and compared to previously published JEV genomes. H225 genome was 10,977-nucleotides long, comprising a single ORF of 10,299-nucleotides, a 5′-UTR of 95 nucleotides and a 3′-UTR of 582 nucleotides. The H225 genome showed high levels of sequence identity with 47 fully sequenced JEV genomes, ranging from 99.3 % to 75.5 % for nucleotides and 99.2 % to 91.5 % for amino acid sequences. Phylogenetic analysis of the full-length sequence indicated that the H225 strain belongs to genotype III and is closely related to the Indian JEV strain Vellore P20778. A comparison of amino acids associated with neurovirulence in the E proteins and non-structural proteins of known virulent and attenuated JEV strains suggested H225 to be a highly virulent strain. This is the first report of whole-genome sequencing of a genotype III JEV genome isolated from equines.  相似文献   
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