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141.
Melissa Adiatman Masayuki Ueno Mari Ohnuki Chiyoko Hakuta Kayoko Shinada Yoko Kawaguchi 《Gerodontology》2013,30(4):262-269
Gerodontology 2012; doi: 10.1111/j.1741‐2358.2012.00673.x Functional tooth units and nutritional status of older people in care homes in Indonesia Objectives: To investigate the relationship between functional tooth units (FTUs) and nutritional status. Methods: One hundred females (mean age: 72.4 ± 8.2 years) at four private care homes in Jakarta, Indonesia were interviewed and clinically examined. The oral examination included the assessment of teeth, prosthetic status, and number of FTUs. The total number of FTUs was further divided by tooth composition: natural tooth against natural tooth (NN‐FTUs), natural tooth against denture (ND‐FTUs), and denture against denture (DD‐FTUs). Nutritional status was evaluated using the body mass index (BMI) and the Mini Nutritional Assessment (MNA). Results: The mean numbers of teeth present, NN‐FTUs, ND‐FTUs, DD‐FTUs, and total FTUs were 13.1 ± 10.4, 1.7 ± 3.0, 1.2 ± 3.3, 0.4 ± 1.2 and 3.3 ± 4.4, respectively. The mean BMI and MNA scores were 24.8 ± 5.0 and 22.6 ± 2.8, respectively. Subjects with a normal BMI had a significantly higher total number of FTUs (3.6 ± 4.6) compared with underweight subjects (0.1 ± 0.3). Subjects with a normal MNA had a significantly higher number of NN‐FTU (2.6 ± 3.7) compared to those who were at risk or in a state of under‐nutrition (1.2 ± 2.4). Conclusion: This study revealed significant relationships between the number of FTUs and nutritional status. Keeping the posterior occlusion should be emphasized in order to maintain good nutritional status in older subjects. 相似文献
142.
Kerem Teralı Rebecca L. Beavil Richard W. Pickersgill Mark van der Giezen 《Biochemical and biophysical research communications》2013
Small inorganic assemblies of alternating ferrous/ferric iron and sulphide ions, so-called iron–sulphur (Fe–S) clusters, are possibly nature’s most ancient prosthetic groups. One of the early actors in Fe–S cluster biosynthesis is a protein complex composed of a cysteine desulphurase, Nfs1, and its functional binding partner, Isd11. Although the essential function of Nfs1·Isd11 in the liberation of elemental sulphur from free cysteine is well established, little is known about its structure. Here, we provide evidence that shows Isd11 has a profound effect on the oligomeric state of Nfs1. 相似文献
143.
AbstractThe semi-empirical thermodynamic model reported in an earlier paper (Hall et al., 1991) is further developed to describe the zeta potential behaviour of an intravenous fat emulsion in the presence of magnesium and zinc cations. The effect of interfacial protonation is also explored. We have now established that a previously reported formation constant for the calcium interaction is actually a conditional value and together with the new data for zinc and magnesium, overall formation constants are calculated. 相似文献
144.
《Archives of animal nutrition》2013,67(3):231-245
Observations were carried out of actual acidity, volatile fatty acid (VFA) concentrations, enzyme activity in the rumen, total protein, urea, total lipid and glucose in the serum of conventional (CL) and gnotobi‐otic lambs (GL) in the period of milk nutrition. The inoculum of gnotobiotic iambs contained Streptococcus bovis, Prevoxella ruminicola, Butyrivibrio fibrisolvens and Selenomonas ruminantium at a concentration of 1.106 each. Throughout the observation period the pH of the rumen contents of gnotobiotic lambs ranged within 6.5–6.8 with a significant difference at an age of 7 weeks. Total VFA concentrations in the rumen contents were increased in the CL throughout milk nutrition; the differences at 4 and 5 weeks of age were significant. Total VFA in the conventional lambs revealed an increasing tendency between weeks 4 and 7, reaching higher levels at 7 weeks of age (57.1 mmol.l"1), whereas in the gnotobiotic animals the range (24.3–30.1 mmol.l"1) was narrow and the peak occurred at 6 weeks of age. In GL significantly increased molar proportions of acetic acid were observed whereas in CL the molar proportions of propionic acid proved to be significant increased. The molar proportions of butyric and valeric acids were increased in CL but the group differences were not significant. In GL no isoacids were found. Alpha amylase (E.C.3.2.1.1.) activity of the rumen contents was significantly increased in GL between weeks 2 and 6 of age whereas cel‐Iulase (endoglucanase E.C.3.2.1.4. and cellobiohydrolase E.C.3.2.1.91.) activity was significantly increased in 4‐week‐old CL. Over the whole period of milk nutrition no significant differences were observed in ure‐ase (E.C.3.5.1.5.) activity of the rumen contents in the examined groups. At 5 weeks of age significantly increased total protein levels were observed in the conventional animals with maximum levels occurring at 4 weeks of age (CL‐59.5 g.l"1 GL‐55.3 g.l"1). Urea levels in 6‐week old conventional lambs were significantly higher than in the gnotobiotic animals (CL‐6.4 mmol.l"’ vs. GL‐1.9 mmol.l"1). As to glycaemia no significant group differences were recorded. In the conventional animals total lipid levels were significantly increased at 1 and 6 weeks of age with a peak occurring in the first week of life (7.5 g.l"1) whereas in the gnotobiotic lambs a significant increase was observed at 3 weeks of age, the peak being recorded in 4 week‐old animals (4.3 g.l"1). Throughout the period of interest the mean daily weight gains in the conventional and gnotobiotic lambs presented 0.164 and 0.162 kg, respectively. The functional development of the rumen was significantly influenced by the complexity of the microfiora. 相似文献
145.
Bark beetles are among the most destructive of pine forest pests and they form close symbiotic relationships with ophiostomatoid fungi. Although some fungi are considered to be mutualistic symbionts of bark beetles with respect to the supply of nutrients, detrimental effects of fungal symbionts on larval growth have also been frequently reported. The mechanisms of such antagonistic effects are hypothesized to be a decrease in nutritional resources caused by competition for saccharides by the fungi. Here, we provide experimental evidence that three beetle-associated fungi modify the nutritional content of an artificial phloem diet, leading to a detrimental effect on the growth of Dendroctonus valens larvae. When larvae were fed a diet of pine phloem in agar medium colonized with any of these fungi, feeding activity was not affected but weight significantly decreased. Additional analysis showed that fungi depleted the fructose and glucose concentrations in the phloem media. Furthermore, these detrimental effects were neutralized by supplementing the media with fructose or glucose, suggesting that fungi may affect larval growth by modifying diet saccharide contents. These data indicate that fungus-induced nutritional changes in bark beetle diet can affect larval growth, and that the mechanism involves fungus-induced saccharide depletion from the larval diet. 相似文献
146.
《Archives of animal nutrition》2013,67(1):20-30
Abstract Lactoferrin (LF) exhibits a broad spectrum of anti-microbial properties and may have regulatory functions in the immune system. In the present study, 40 calves (20 males, 20 females) were used to examine the effects of supplemental bovine LF added to colostrum and milk replacer (at 0.16%) on health, weight development and feed intake during a 70-day experimental period. The calves were allocated to a treatment group (n = 20) and a control group (n = 20); the groups were balanced in terms of sex, live weight and date of birth. Body weight and feed intake were measured at regular intervals. Blood and colostrum samples were collected to determine the content of IgG. In addition, colostrum and milk replacer samples were analysed for their LF concentrations. Significantly higher IgG values were observed in the LF treated than in the control group during the entire feeding experiment from week 2 to week 6. Calves receiving LF had less days of disease with less serious cases of diarrhoea than the control group. Body weight and feed intake were not significantly different between the treatments; in male calves LF-treated animals tended towards higher weight gains. This study indicates that LF is advantageous for health and may therefore be a beneficial supplement in the diets for neonatal calves. 相似文献
147.
148.
NH4 : NO3 nutrition influence on biomass productivity and root respiration of poplar and willow clones 下载免费PDF全文
Nitrogen fertilization often improves the yield of intensively managed, short‐rotation coppices. However, information of N nutrition form on the growth of common species and clones used for biomass production is limited. Thus, this study aims at evaluating N form effects on the growth of two Salicaceae clones. Cuttings of the poplar clone Max 4 (Populus maximovizcii × P. nigra) and the willow clone Inger (Salix triandra × S. viminialis) were fertilized in a pot experiment with four ratios of nitrate (NO3?) to ammonium (50%, 62.5%, 75% and 87.5% NO3? balanced with ammonium (NH4+) to constant total N) for one growing season and under stable soil pH. Plants were harvested for analysis of biomass and morphology of leaves, stem and roots. Respiration of fine and coarse roots (RR) was determined and related to biomass growth. Salix cv. Inger accumulated more total dry matter than Populus cv. Max 4. In both Salicaceae clones, the total biomass was significantly influenced by the nitrate ratio and greatest in plants fertilized with 50% NO3? of the total N supply. Both clones possess a different leaf and root morphology, but no significant influence of the NO3? ratio on the morphology was found. Fine RR rates differed significantly between clones, with significantly greater fine RR in Max 4; 87.5% NO3? fertilization increased the fine RR. Fine RR and total accumulated plant biomass were closely related. Our study is the first to show the tremendous influence of fine root respiration, especially including the carbon‐intensive reduction of NO3? to NH4+, on the aboveground growth of Salicaceae clones. Ways to improve yield in SRC are thus to lower the assimilate consumption by fine roots and to match fertilization regimes to the used clones or vice versa. 相似文献
149.
150.
Harriet Bunning Lee Bassett Christina Clowser James Rapkin Kim Jensen Clarissa M. House Catharine R. Archer John Hunt 《Ecology and evolution》2016,6(14):4711-4730
Sexual selection may cause dietary requirements for reproduction to diverge across the sexes and promote the evolution of different foraging strategies in males and females. However, our understanding of how the sexes regulate their nutrition and the effects that this has on sex‐specific fitness is limited. We quantified how protein (P) and carbohydrate (C) intakes affect reproductive traits in male (pheromone expression) and female (clutch size and gestation time) cockroaches (Nauphoeta cinerea). We then determined how the sexes regulate their intake of nutrients when restricted to a single diet and when given dietary choice and how this affected expression of these important reproductive traits. Pheromone levels that improve male attractiveness, female clutch size and gestation time all peaked at a high daily intake of P:C in a 1:8 ratio. This is surprising because female insects typically require more P than males to maximize reproduction. The relatively low P requirement of females may reflect the action of cockroach endosymbionts that help recycle stored nitrogen for protein synthesis. When constrained to a single diet, both sexes prioritized regulating their daily intake of P over C, although this prioritization was stronger in females than males. When given the choice between diets, both sexes actively regulated their intake of nutrients at a 1:4.8 P:C ratio. The P:C ratio did not overlap exactly with the intake of nutrients that optimized reproductive trait expression. Despite this, cockroaches of both sexes that were given dietary choice generally improved the mean and reduced the variance in all reproductive traits we measured relative to animals fed a single diet from the diet choice pair. This pattern was not as strong when compared to the single best diet in our geometric array, suggesting that the relationship between nutrient balancing and reproduction is complex in this species. 相似文献