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21.
Gymnosporia buxifolia (Celastraceae) is a well-known traditional medicinal plant used to treat various diseases. The aim of the study was to quantify the total phenolic and flavonoid content of cell biomass of G. buxifolia developed in vitro using plant growth regulators (PGRs), phloroglucinol (PG) and an antagonist of cytokinin activity 6-(2-hydroxy-3-methylbenzylamino) purine (PI55). The antibacterial activity of calli was also evaluated. The accumulation of phenolic contents and its antibacterial activity in the cell biomass varied between the treatments as well as the mother plant. Generally, a higher accumulation of phenolic contents translated to improved activity against selected pathogenic bacteria. This was apparent in biomass derived from solid and liquid MS media containing combinations of 5 µM PG, 1.5 µM benzyladenine (BA) or meta-topolin (mT) with or without 1 µM picloram (Pic) and 5 µM PG or PI55, 1 µM BA with or without 0.5 µM Pic respectively. The choice of PGRs, PG and PI55 treatments used during in vitro cell culture systems influenced the therapeutic potential of G. buxifolia. Our results indicate that the cell biomass from suspension and/or solid culture of G. buxifolia could be promising as antibacterial agents with possible applications in the pharmaceutical industry.  相似文献   
22.
The effects of plant growth regulators (PGRs) and organic elicitors (OEs) on in vitro propagation of Eucomis autumnalis was established. Three-year-old ex vitro grown plants from organogenesis of E. autumnalis and somatic embryogenesis (previously reported protocol) of Drimia robusta were investigated for antibacterial activity. In vitro propagation from leaf explants of E. autumnalis was established using different PGRs and OE treatments for mass propagation, biomass production and bioactivity analysis to supplement the use of wild plant material. Prolific shoots (16.0?±?0.94 shoots per explant) were obtained with MS (Murashige and Skoog in Physiol Plant 15:473–497, 1962) medium containing 100 mg l?1 haemoglobin (HB), 10 µM benzyladenine (BA) and 2 µM naphthaleneacetic acid (NAA). The shoots were rooted effectively with a combination of 2.5 µM indole-3-acetic acid and 5.0 µM indole-3-butyric acid. The plantlets were successfully acclimatized in a vermiculite-soil mixture (1:1 v/v) in the greenhouse. Three-year-old ex vitro-grown E. autumnalis and D. robusta plants derived via organogenesis and somatic embryogenesis respectively exhibited antibacterial activity and varied with PGR and OE treatments, plant parts and bacteria. The leaves of E. autumnalis ex vitro-derived from a combination of HB, BA and NAA followed by the individual treatments of BA and HB gave the best antibacterial activities (<?1 mg ml?1: minimum inhibitory concentration from 0.098 to 0.78 mg ml?1) against all tested pathogenic bacteria (Bacillus subtilis, Enterococcus faecalis, Micrococcus luteus, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa). The bulbs of D. robusta ex vitro-derived from solid culture with 10 µM picloram, 1 µM thidiazuron and 20 µM glutamine exhibited good antibacterial activity against E. faecalis, M. luteus and S. aureus when compared with other treatments and mother plants. The ex vitro-grown E. autumnalis and D. robusta biomass produced with PGRs along with OE treatments confirmed a good potent bioresource and can be used as antibacterial agents. The in vitro plant regeneration of E. autumnalis and D. robusta protocols and ex vitro plants could be used for conservation strategies, bioactivity and traditional medicinal use.  相似文献   
23.
The site-specific quantitation of N- and O-glycosylation is vital to understanding the function(s) of different glycans expressed at a given site of a protein under physiological and disease conditions. Most commonly used precursor ion intensity based quantification method is less accurate and other labeled methods are expensive and require enrichment of glycopeptides. Here, we used glycopeptide product (y and Y0) ions and 18O–labeling of C-terminal carboxyl group as a strategy to obtain quantitative information about fold-change and relative abundance of most of the glycoforms attached to the glycopeptides. As a proof of concept, the accuracy and robustness of this targeted, relative quantification LC-MS method was demonstrated using Rituximab. Furthermore, the N-glycopeptide quantification results were compared with a biosimilar of Rituximab and validated with quantitative data obtained from 2-AB-UHPLC-FL method. We further demonstrated the intensity fold-change and relative abundance of 46 unique N- and O-glycopeptides and aglycopeptides from innovator and biosimilar samples of Etanercept using both the normal-MS and product ion based quantitation. The results showed a very similar site-specific expression of N- and O-glycopeptides between the samples but with subtle differences. Interestingly, we have also been able to quantify macro-heterogeneity of all N- and O-glycopetides of Etanercept. In addition to applications in biotherapeutics, the developed method can also be used for site-specific quantitation of N- and O-glycopeptides and aglycopeptides of glycoproteins with known glycosylation pattern.  相似文献   
24.

Background  

Plant Growth Promoting Rhizobacteria (PGPR), Pseudomonas fluorescens strain KH-1 was found to exhibit plant growth promotional activity in rice under both in-vitro and in-vivo conditions. But the mechanism underlying such promotional activity of P. fluorescens is not yet understood clearly. In this study, efforts were made to elucidate the molecular responses of rice plants to P. fluorescens treatment through protein profiling. Two-dimensional polyacrylamide gel electrophoresis strategy was adopted to identify the PGPR responsive proteins and the differentially expressed proteins were analyzed by mass spectrometry.  相似文献   
25.
26.
Due to the risks to the foetus with invasive prenatal diagnosis, non-invasive prenatal diagnosis (NIPD) is gaining tremendous interest but no reliable method that can be widely used has been developed to date. Manipulation of foetal cells and foetal cell-free genetic material in the maternal blood are two promising approaches being researched. The manipulation of foetal cells in the maternal circulation is more popular as it can provide complete genetic information of the foetus particularly the diagnosis of aneuploidies. However, the foetal cell numbers in the maternal circulation are small and their enrichment and ex vivo culture remain two major challenges for NIPD. Primitive foetal erythroblasts (pFEs) have been considered as a good potential candidate for early first trimester NIPD but their nature, properties and manipulation to provide adequate cell numbers remain a challenging task and several approaches need to be meticulously evaluated. In this review we describe the current status of NIPD and suggest some novel approaches in manipulating pFEs for future clinical application of NIPD. These novel approaches include (1) understanding the pFE enucleation process, (2) enriching pFE numbers by individual pick-up of pFEs from maternal blood using micromanipulation and microdroplet culture, (3) expansion of pFEs using mitogens and (4) decondensation of the pFE nucleus with histone deacetylase (HDAC) inhibitors followed by reprogramming using gene delivery protocols with/without small reprogramming molecules to improve reprogrammed pFE proliferation rates for successful NIPD.  相似文献   
27.
Wheat germ agglutinin (WGA) is a plant lectin, which specifically recognizes the sugars NeuNAc and GlcNAc. Mutated WGA with enhanced binding specificity can be used as biomarkers for cancer. In silico mutations are performed at the active site of WGA to enhance the binding specificity towards sialylglycans, and molecular dynamics simulations of 20 ns are carried out for wild type and mutated WGAs (WGA1, WGA2, and WGA3) in complex with sialylgalactose to examine the change in binding specificity. MD simulations reveal the change in binding specificity of wild type and mutated WGAs towards sialylgalactose and bound conformational flexibility of sialylgalactose. The mutated polar amino acid residues Asn114 (S114N), Lys118 (G118K), and Arg118 (G118R) make direct and water mediated hydrogen bonds and hydrophobic interactions with sialylgalactose. An analysis of possible hydrogen bonds, hydrophobic interactions, total pair wise interaction energy between active site residues and sialylgalactose and MM‐PBSA free energy calculation reveals the plausible binding modes and the role of water in stabilizing different binding modes. An interesting observation is that the binding specificity of mutated WGAs (cyborg lectin) towards sialylgalactose is found to be higher in double point mutation (WGA3). One of the substituted residues Arg118 plays a crucial role in sugar binding. Based on the interactions and energy calculations, it is concluded that the order of binding specificity of WGAs towards sialylgalactose is WGA3 > WGA1 > WGA2 > WGA. On comparing with the wild type, double point mutated WGA (WGA3) exhibits increased specificity towards sialylgalactose, and thus, it can be effectively used in targeted drug delivery and as biological cell marker in cancer therapeutics. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
28.

Background

Configuring high quality care for the rapidly increasing number of people with type 2 diabetes (T2D) is a major challenge worldwide for both providers and commissioners. In the UK, about two thirds of people with T2D are managed entirely in primary care, with wide variation in management strategies and achievement of targets. Pay for performance, introduced in 2004, initially resulted in improvements but disparities exist in ethnic minorities and the improvements are levelling off. Community based, intermediate care clinics for diabetes (ICCDs) were considered one solution and are functioning across the UK. However, there is no randomised trial evidence for the effectiveness of such clinics.

Trial Design, Methods and Findings

This is a cluster-randomised trial, involving 3 primary care trusts, with 49 general practices randomised to usual care (n = 25) or intervention (ICCDs; n = 24). All eligible adult patients with T2D were invited; 1997 were recruited and 1280 followed-up after 18-months intervention. Primary outcome: achievement of all three of the NICE targets [(HbA1c≤7.0%/53 mmol/mol; Blood Pressure <140/80 mmHg; cholesterol <154 mg/dl (4 mmol/l)]. Primary outcome was achieved in 14.3% in the intervention arm vs. 9.3% in the control arm (p = 0.059 after adjustment for covariates). The odds ratio (95% CI) for achieving primary outcome in the intervention group was 1.56 (0.98, 2.49). Primary care and community clinic costs were significantly higher in the intervention group, but there were no significant differences in hospital costs or overall healthcare costs. An incremental cost-effectiveness ratio (ICER) of +£7,778 per QALY gained, indicated ICCD was marginally more expensive at producing health gain.

Conclusions

Intermediate care clinics can contribute to improving target achievement in patients with diabetes. Further work is needed to investigate the optimal scale and organisational structure of ICCD services and whether, over time, their role may change as skill levels in primary care increase.

Trial Registration

ClinicalTrials.gov NCT00945204; National Research Register (NRR) M0014178167.  相似文献   
29.
Every year, a huge quantity of fishery wastes and by-products are generated by fish processing industries. These wastes are either underutilized to produce low market value products or dumped leading to environmental issues. Complete utilization of fishery wastes for recovering value added products would be beneficial to the society and individual. The fish protein hydrolysates and derived peptides of fishery resources are widely used as nutritional supplements, functional ingredients, and flavor enhancers in food, beverage and pharmaceutical industries. Antioxidants from fishery resources have attracted the attention of researchers as they are cheaper in cost, easy to derive, and do not have side effects. Thus the present investigation was designed to produce protein hydrolysate by pepsin and papain digestion from the backbones of Rastrelliger kanagurta (Indian mackerel) and evaluate its antioxidant properties through various in vitro assays. The results reveal that both hydrolysates are potent antioxidants, capable of scavenging 46% and 36% of DPPH (1,1-diphenyl-2 picrylhydrazyl) and 58.5% and 37.54% of superoxide radicals respectively. The hydrolysates exhibit significant (p < 0.05) reducing power and lipid peroxidation inhibition. Among the two hydrolysates produced, pepsin derived fraction is superior than papain derived fraction in terms of yield, DH (Degree of hydrolysis), and antioxidant activity.  相似文献   
30.
The plant specific DREPP proteins have been shown to bind Ca2+ and regulate the N-myristoylation signaling and microtubule polymerization in Arabidopsis thaliana. The information about DREPP proteins in other plants is, however, scarce. In the present study, we isolated the DREPP gene from a halophytic grass, Sporobolus virginicus, and tested whether the gene was involved in alkaline salt stress responses. The SvDREPP1 was cloned from S. virginicus by RACE methods. The isolated gene showed high homology to DREPP homologs from C4 grasses, Setaria italica, and Panicum hallii as well as rice (OsDREPP1). The encoded protein contained 202 amino acid residues. It was expressed in E. coli, and its biochemical properties were studied. It was observed that SvDREPP1 was not only Ca2+-binding protein, but also bind to calmodulin and microtubules. The SvDREPP1 mRNA expression in plants grown under alkaline salt stress was upregulated by 3.5 times over the control in leaf tissues after 48-h treatment, whereas it was increased for 6.0 times in the root tissues at 36 h. The data suggests the importance of SvDREPP1 in regulating alkali salt stress responses in the leaf tissues.  相似文献   
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