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901.
Norimah AK H. C. Koo Hamid Jan JM Mohd Nasir MT S. Y. Tan Mahendran Appukutty Nurliyana AR Frank Thielecke Sinead Hopkins M. K. Ong C. Ning E. S. Tee 《PloS one》2015,10(10)
Background
Diets rich in whole grain are associated with several health benefits. Little is known however, about whole grain consumption patterns in Malaysia. The aim of this study was to assess whole grain intakes and dietary source in Malaysian children and adolescents.Methods
This analysis is from the MyBreakfast study, a national cross sectional study investigating eating habits among primary and secondary school children throughout Malaysia, conducted in 2013. Children (n = 5,165) and adolescents (n = 2,947) who completed two days of dietary assessment using a food record or recall respectively were included. The whole grain content of foods was estimated mainly through the use of quantitative ingredient declarations on food labels. All wholegrain foods were considered irrespective of the amount of whole grain they contained.Results
Overall, only 25% of children and 19% of adolescents were wholegrain consumers. Mean daily intakes in the total sample were 2.3g/d (SD 5.8g/d) in children and 1.7g/d (SD 4.7g/d) in adolescents and in the consumer’s only sample, mean intakes reached 9.1g/d (SD 8.6) and 9.2g/d (SD 7.1g/d) respectively. Wheat was the main grain source of whole grain while ready to eat breakfast cereals and hot cereals were the main food contributors. Less than 3% of the children and adolescents reached the US quantitative whole grain recommendation of 48g/day.Conclusion
Whole grain is consumed by only a minority of Malaysian children and adolescents and even among consumers, intakes are well below recommendations. Efforts are needed to firstly understand the barriers to whole grain consumption among Malaysian children in order to design effective health promotion initiatives to promote an increase in whole grain consumption. 相似文献902.
Shahnaz Shahidi‐Noghabi Els JM Van Damme Kamran Mahdian Guy Smagghe 《Archives of insect biochemistry and physiology》2010,75(3):207-220
In this project, the toxicity and mechanism of action of the ricin‐B‐related lectin SNA‐I from elderberry (Sambucus nigra) in the pea aphid (Acyrthosiphon pisum) and the beet armyworm (Spodoptera exigua), two important pest insects in agriculture, were studied. SNA‐I is a chimeric lectin belonging to the class of ribosome‐inactivating proteins and consists of an A‐chain with N‐glycosidase activity and a carbohydrate‐binding B‐chain. Incorporation of 2 mg/ml of SNA‐I in the diet of neonates and adults of A. pisum caused 40–46% mortality within 2 days, while in third instars of S. exigua, the larval biomass was significantly reduced by 12% after feeding for 3 days on a diet containing 5 mg/g of SNA‐I. Interestingly, extracts of the (mid)gut of treated A. pisum and S. exigua demonstrated DNA fragmentation and this was accompanied with an increase in caspase‐3‐like activity. The involvement of cell death or apoptosis in the entomotoxicity of SNA‐I through induction of caspase‐3‐like activity was also confirmed by addition of the permeable caspase‐3 inhibitor III in the diet, leading to a rescue of the treated aphid neonates. Finally, similar to the chimeric lectin SNA‐I, the hololectin SNA‐II, consisting of two carbohydrate‐binding B‐chains caused high mortality to neonate A. pisum aphids with an LC50 of 1.59 mg/ml, suggesting that the entomotoxic action of the lectins under study mainly relies on their carbohydrate‐binding activity. © 2010 Wiley Periodicals, Inc. 相似文献
903.
Alireza Babaei Seyed Reza Tabaei-Aghdaei Morteza Khosh-Khui Reza Omidbaigi Mohammad Reza Naghavi Gerhard D Esselink Marinus JM Smulders 《BMC plant biology》2007,7(1):12
Background
Damask roses (Rosa damascena Mill.) are mainly used for essential oil production. Previous studies have indicated that all production material in Bulgaria and Turkey consists of only one genotype. Nine polymorphic microsatellite markers were used to analyze the genetic diversity of 40 accessions of R. damascena collected across major and minor rose oil production areas in Iran. 相似文献904.
Large single crystals of rabbit liver fructose-1,6-diphosphatase suitable for a high resolution structure analysis have been grown from polyethylene glycol. The space group of these crystals is I222 with a = 75 A, b = 81 A, and c = 132 A and there are 2 tetrameric molecules in the unit cell. These crystals have one protein subunit as the crystallographic asymmetric unit and establish point group symmetry 222 as the molecular symmetry. 相似文献
905.
Arco J Teske Bart WL De Boeck Paul G Melman Gertjan T Sieswerda Pieter A Doevendans Maarten JM Cramer 《Cardiovascular ultrasound》2007,5(1):1-19
Recent developments in the field of echocardiography have allowed the cardiologist to objectively quantify regional and global myocardial function. Regional deformation (strain) and deformation rate (strain-rate) can be calculated non-invasively in both the left and right ventricle, providing information on regional (dys-)function in a variety of clinical settings. Although this promising novel technique is increasingly applied in clinical and preclinical research, knowledge about the principles, limitations and technical issues of this technique is mandatory for reliable results and for implementation both in the clinical as well as the scientific field. In this article, we aim to explain the fundamental concepts and potential clinical applicability of strain and strain-rate for both tissue Doppler imaging (TDI) derived and speckle tracking (2D-strain) derived deformation imaging. In addition, a step-by-step approach to image acquisition and post processing is proposed. Finally, clinical examples of deformation imaging in hypertrophic cardiomyopathy (HCM), cardiac resynchronization therapy (CRT) and arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) are presented. 相似文献
906.
Regulatory role of SH3 domain-mediated protein-protein interactions in synaptic vesicle endocytosis.
P S McPherson 《Cellular signalling》1999,11(4):229-238
Src homology (SH) 3 domains are small modules found in a diverse array of proteins. The presence of an SH3 domain confers upon its resident protein the ability to interact with specific proline-rich sequences in protein binding partners. A major focus of research has highlighted a role for SH3 domain-mediated interactions in the regulation of signal transduction events. However, more recent data has suggested an important function for SH3 domains in vesicular trafficking. This review will focus on this newly emerging role with a particular emphasis on the molecular components involved in synaptic vesicle endocytosis and the regulatory role of SH3 domain-mediated protein-protein interactions in this process. 相似文献
907.
Cholinergic stimulation of inositol phosphate formation was studied in isolated rat pancreatic acini, prelabelled with myo-[2-3H]inositol. Carbamylcholine increased incorporation of radioactivity into Ins(1,4,5)P3 and InsP4 within 5 s. Increases in [3H]Ins(1,3,4)P3 were delayed with marked stimulation occurring between 10 s and 1 min. Inositol polyphosphate formation was less sensitive to carbamylcholine concentration than was stimulation of amylase release. At a low (0.3 microM) carbamylcholine concentration, no increase in inositol polyphosphate formation was detected, whereas stimulation of amylase release, which was not dependent on extracellular calcium, was observed. Ins(1,4,5)P3 was shown to release actively accumulated 45Ca2+ from isolated rough endoplasmic reticulum membranes to a similar extent as that released from rough endoplasmic reticulum following cholinergic stimulation of pancreatic acini (Richardson, A.E. et al. (1984) Biochem. Soc. Trans. 12, 1066-1067). The data is consistent with Ins(1,4,5)P3 being produced rapidly enough to release sufficient calcium from the rough endoplasmic reticulum to cause an observed increases in cytoplasmic free Ca2+. 相似文献
908.
Laura Tamblyn Erica Li Haya Sarras Prarthana Srikanth M. Prakash Hande J. Peter McPherson 《Mutation research》2009,660(1-2):57-65
Hexavalent chromium (Cr[VI]) is a toxic environmental contaminant that is capable of producing a broad spectrum of DNA damage. The ability of Cr[VI] to induce mutagenesis and neoplastic transformation has been attributed to its genotoxic action, however our understanding of molecular mechanisms involved in the repair of Cr[VI]-induced DNA damage remains incomplete. Here, we report that Mus81, an enzyme that participates with Eme1 in the resolution of replication fork damage caused by certain lesions, is involved in the repair of Cr[VI]-induced DNA damage. Mus81-deficient cells were found to be more susceptible to Cr[VI]-induced proliferation arrest and more sensitive to the long-term cytotoxic effects of Cr[VI] than isogenic wild-type cells. Following Cr[VI] exposure, Mus81-deficient cells displayed a lag in the disappearance of Rad51 foci, exhibited elevated replication-associated γ-H2AX and showed an increased incidence of chromosomal instability compared to wild-type cells. Our findings support a role for Mus81 in the resolution of replication-associated DNA damage associated with this genotoxic agent, by converting Cr[VI]-DNA lesions into a form more amenable for homologous recombination. 相似文献
909.
BACKGROUND: Septins are members of a conserved family of GTPases found in organisms as diverse as budding yeast and mammals. In budding yeast, septins form hetero-oligomeric filaments that lie adjacent to the membrane at the mother-bud neck, whereas in mammals, they concentrate at the cleavage furrow of mitotic cells; in both cases, septins provide a required function for cytokinesis. What directs the location and determines the stability of septin filaments, however, remains unknown. RESULTS: Here we show that the mammalian septin H5 is associated with the plasma membrane and specifically binds the phospholipids phosphatidylinositol 4, 5-bisphosphate (PtdIns(4,5)P(2)) and phosphatidylinositol 3,4, 5-trisphosphate (PtdIns(3,4,5)P(3)). Deletion analysis revealed that this binding occurs at a site rich in basic residues that is conserved in most septins and is located adjacent to the GTP-binding motif. Phosphoinositide binding was inhibited by mutations within this motif and was also blocked by agents known to associate with PtdInsP(2) or by a peptide corresponding to the predicted PtdInsP(2)-binding sequence of H5. GTP binding and hydrolysis by H5 significantly reduced its PtdInsP(2)-binding capability. Treatment of cells with agents that occluded, dephosphorylated or degraded PtdInsP(2) altered the appearance and localization of H5. CONCLUSIONS: These results indicate that the interaction of septins with PtdInsP(2) might be an important cellular mechanism for the spatial and temporal control of septin accumulation. 相似文献
910.
Abstract A proteolytically modified form of the Escherichia coli single-stranded DNA-Binding protein (SSB) has been crystallized from 15% saturated sodium citrate. Crystals as large as 1.0mm × 0.3mm × 0.2mm were obtained and these diffract beyond 3Å resolution. X-ray photographic analysis demonstrated a rhombohedral unit cell of space group R3 with an equivalent triple centered hexagonal unit cell having dimensions of a = b = 62.9 A and c = 264.3A. These crystals were judged to be adequate for a three dimensional structure determination. 相似文献