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991.
Fusion of oil bodies in endosperm of oat grains 总被引:1,自引:0,他引:1
Heneen WK Karlsson G Brismar K Gummeson PO Marttila S Leonova S Carlsson AS Bafor M Banas A Mattsson B Debski H Stymne S 《Planta》2008,228(4):589-599
Few microscopical studies have been made on lipid storage in oat grains, with variable results as to the extent of lipid accumulation in the starchy endosperm. Grains of medium- and high-lipid oat (Avena sativa L.) were studied at two developmental stages and at maturity, by light microscopy using different staining methods, and by scanning and transmission electron microscopy. Discrete oil bodies occurred in the aleurone layer, scutellum and embryo. In contrast, oil bodies in the starchy endosperm often had diffuse boundaries and fused with each other and with protein vacuoles during grain development, forming a continuous oil matrix between the protein and starch components. The different microscopical methods were confirmative to each other regarding the coalescence of oil bodies, a phenomenon probably correlated with the reduced amount of oil-body associated proteins in the endosperm. This was supported experimentally by SDS-PAGE separation of oil-body proteins and immunoblotting and immunolocalization with antibodies against a 16 kD oil-body protein. Much more oil-body proteins per amount of oil occurred in the embryo and scutellum than in the endosperm. Immunolocalization of 14 and 16 kD oil-body associated proteins on sectioned grains resulted in more heavy labeling of the embryo, scutellum and aleurone layer than the rest of the endosperm. Observations on the appearance of oil bodies at an early stage of development pertain to the prevailing hypotheses of oil-body biogenesis. 相似文献
992.
993.
994.
Josef Finsterer Anders Fuglsang-Frederiksen 《Journal of electromyography and kinesiology》2003,13(2):191-196
Quantification of needle-induced insertional activity (IA) by means of the turn/amplitude analysis (TAA) has not been attempted so far. IA was recorded from the right brachial biceps and right anterior tibial muscle of 29 healthy subjects, 17 woman, 12 men, aged 24-79 years and 51 patients with neuromuscular disorders (29 neuropathies and 22 myopathies), 24 woman, 27 men, aged 17-81 years. IA was analyzed with regard to IA duration (IAD), turns/second (T/S), amplitude/turn (A/T), T/S:IAD and A/T:IAD. IAD was not significantly different between healthy and diseased subjects in either of the two investigated muscles. On the contrary, T/S, A/T, T/S:IAD and A/T:IAD were significantly increased in the brachial biceps and anterior tibial muscle of patients with neuropathies. In myopathies T/S were increased in both muscles and the T/S:IAD in the anterior tibial muscle. Quantification of IA by TAA increases the sensitivity of conventional EMG from 38 to 69% in neuropathies and from 41 to 73% in myopathies. It is concluded that quantification of IA by TAA is of diagnostic support in the detection of neuromuscular disorders. The most useful parameter in this respect is the T/S, which, contrary to IAD, is increased in patients with neuropathies as well as patients with myopathies. 相似文献
995.
Saino Nicola; Ambrosini Roberto; Martinelli Roberta; Ninni Paola; Moller Anders Pape 《Behavioral ecology》2003,14(1):16-22
In some passerines, parents allocate more food to offspringwith the brightest red gapes, but the function of parental decisionsbased on offspring gape coloration is unknown. We hypothesizethat gape coloration is part of a communication system wherenestlings reveal their condition to attending parents, whichmay thus base their decisions on reliable signals of offspringreproductive value. We analyze the effects of brood size manipulation,injection with an immunogen and food deprivation, on gape coloration,morphology, and T-cellmediated immunocompetence of nestlingbarn swallows (Hirundo rustica). For each gape we measured threecomponents of coloration (hue, saturation, and brightness) andobtained an overall color score by principal component analysis.Enlargement of brood size and injection with an antigen resultedin less red and less saturated and brighter gape color. Nestlingsin enlarged broods had smaller body mass and T-cellmediatedimmunocompetence compared to those in reduced broods. A positivecovariation existed between redness and saturation of gape colorand T-cellmediated immunocompetence. Gape color siblingsraised in different nests did not depend on parentage. Thus,condition-dependent gape coloration can reveal different componentsof nestling state on which parents may base their adaptive decisionsabout allocation of care to the offspring. 相似文献
996.
Previous studies have shown no significant effect of experimentaltail length manipulation in female barn swallows (Hirundo rustica)at the beginning of a breeding season on reproductive successor behavior during that breeding season. In the present study,we investigate if tail length manipulation had any effect onreproductive performance the following year, the so-called long-termeffect, in contrast to the short-term effects already studied.We found that females with experimentally elongated externaltail feathers at the beginning of a breeding season producedless offspring during the breeding season the following yearthan did females with shortened or unmanipulated tails. Theseresults suggest that tail elongation caused flight deficienciesthat deteriorated the condition of females and eventually reducedreproductive success. The finding of long-term effects but nosignificant short-term effects for female tail elongation suggeststhat female barn swallows have the ability to adjust immediateparental investment. Detrimental effects of long tails in femalesin terms of decreased reproductive success might explain whyfemale tails are not as long as those of males. Finally, femalesmated to long-tailed (sexually attractive) males decreased theirreproductive success the following year more than did femalesmated to short-tailed males, possibly owing to differentialparental effort causing a deterioration of their condition. 相似文献
997.
Skeletal growth and tissue remodelling processes are characterized by an elevated collagen and proteoglycan biosynthesis.
The xylosyltransferases I and II are the rate-limiting step enzymes in proteoglycan biosynthesis and serum xylosyltransferase
(XT) activity has been shown to be a biomarker for the actual proteoglycan biosynthesis rate. Here, XT, alkaline phosphatase
(ALP), bone ALP (BALP) activities were measured in 133 juvenile Caucasians. Serum XT activities in juveniles were elevated
and significantly correlated with ALP and BALP. In an osteoblast-like cell model using SAOS-2 cells mineralization and bone
nodule formation were induced and XT-I, XT-II and ALP were monitored. Induction of mineralization in SAOS-2 cells resulted
in a long-term increase of XT-I mRNA and enzyme activity, which could be paralleled with elevated ALP activity. In addition,
HGH and IGF-I treatment of SAOS-2 cells led to an increased expression of XT-I and ALP. These results point to skeletal growth
and tissue remodeling as a cause of the high XT activity in children. 相似文献
998.
Protein domain prediction is often the preliminary step in both experimental and computational protein research. Here we present a new method to predict the domain boundaries of a multidomain protein from its amino acid sequence using a fuzzy mean operator. Using the nr-sequence database together with a reference protein set (RPS) containing known domain boundaries, the operator is used to assign a likelihood value for each residue of the query sequence as belonging to a domain boundary. This procedure robustly identifies contiguous boundary regions. For a dataset with a maximum sequence identity of 30%, the average domain prediction accuracy of our method is 97% for one domain proteins and 58% for multidomain proteins. The presented model is capable of using new sequence/structure information without re-parameterization after each RPS update. When tested on a current database using a four year old RPS and on a database that contains different domain definitions than those used to train the models, our method consistently yielded the same accuracy while two other published methods did not. A comparison with other domain prediction methods used in the CASP7 competition indicates that our method performs better than existing sequence-based methods. 相似文献
999.
Mozaffari F Lindemalm C Choudhury A Granstam-Björneklett H Lekander M Nilsson B Ojutkangas ML Osterborg A Bergkvist L Mellstedt H 《Cancer immunology, immunotherapy : CII》2009,58(1):111-120
Immunotherapy is being increasingly utilized for adjuvant treatment for breast cancer (BC). We have previously described immune
functions during primary therapy for BC. The present study describes immune recovery patterns during long-term, unmaintained
follow-up after completion of adjuvant therapy.A group of patients with primary BC had been treated with adjuvant radio-chemotherapy
(RT + CT) 5-fluorouracil, epirubicin and cyclophosphamide (FEC) (n = 21) and another group with radiotherapy (RT) (n = 20) alone. Immunological testing of NK and T-cell functions was performed initially at the end of adjuvant treatment and
repeated after 2, 6 and 12 months. NK cell cytotoxicity was significantly higher (P < 0.05) at all time-points in patients than in age-matched controls and did not differ between the two treatments groups
during one year observation. In contrast, lower numbers of CD4 T-cells and lower expression of CD28 on T-cells was observed
particularly in RT + CT patients and did not normalize during the observation period. The numbers of Treg cells (CD4+CD25high) were low in the RT + CT group during follow-up, as well as expression of TCRξ, Zap70, p56lck, P59fyn and PI3 k in CD4+ cells. In contrast, expression of intracellular cytokines (IFN-γ, IL-2, IL-4) in CD4 and CD8 T cells were significantly higher
in RT + CT patients than in the RT group and the difference increased during follow-up. In conclusion, NK-cell cytotoxicity
increased during unmaintained long-term follow-up whereas CD4 and regulatory T cells as well as signal transduction molecules
remained low following adjuvant radio-chemotherapy. 相似文献
1000.
Assessing the use of genomic DNA as a predictor of the maximum absorbance wavelength of avian SWS1 opsin visual pigments 总被引:1,自引:1,他引:0
Anders Ödeen Nathan S. Hart Olle Håstad 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2009,195(2):167-173
Recently, in vitro mutation studies have made it possible to predict the wavelengths of maximum absorbance (λmax) of avian UV/violet sensitive visual pigments (SWS1) from the identity of a few key amino acid residues in the opsin gene.
Given that the absorbance spectrum of a cone’s visual pigment and of its pigmented oil droplet can be predicted from just
the λmax, it may become possible to predict the entire spectral sensitivity of a bird using genetic samples from live birds or museum
specimens. However, whilst this concept is attractive, it must be validated to assess the reliability of the predictions of
λmax from opsin amino acid sequences. In this paper, we have obtained partial sequences covering three of the known spectral tuning
sites in the SWS1 opsin and predicted λmax of all bird species for which the spectral absorbance has been measured using microspectrophotometry. Our results validate
the use of molecular data from genomic DNA to predict the gross differences in λmax between the violet- and ultraviolet-sensitive subtypes of SWS1 opsin. Additionally, we demonstrate that a bird, the bobolink
Dolichonyx oryzivorus L., can have more than one SWS1 visual pigment in its retina. 相似文献