bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dietary fat influences Ia antigen expression, cytokines and prostaglandin E2production of immune cells in autoimmune-prone NZB x NZW F1 mice
Authors: lin Bi-Fong , Huang Chao-Chi , Chiang Bor-Luen , Jeng Su-Jen 
Published: September 2005

AbstractsTo elucidate further the influences of dietary fat on autoimmune diseases, two groups of NZB/W F1 mice were fed with diets containing 200 g dietary fat/kg and 50 g dietary fat/kg (control) respectively. The difference in energy intake between these two groups was compensated with carbohydrate. Mice were bled regularly every month and some of them were killed forin vitroexperiments after 5 months experimental diets. Higher immunoglobulin (Ig)M and IgG anti-double stranded DNA antibody levels, shortened life span and worsened proteinuria were noted in mice fed on the high-fat diet compared with those fed on 50g dietary fat/kg. Phenotypic analyses of spleen cells and peritoneal exudate cells showed that the percentage of CD5+B cells and the mean fluorescent intensity of major histocompatibility molecules on the surface of both types of cells were higher in mice fed on the high-fat diet. In general, higher type 2 T-helper cell activity was noted in mice fed on the high-fat diet. In addition, cytokines such as interleukin-6, tumour necrosis factor-α and prostaglandin E2(PGE2) produced by lipopolysaccharide-stimulated peritoneal exudate cells were also higher in the high-dietary-fat group. These studies suggest that high dietary fat and its related PGE2level might have a critical effect on the frequency of CD5+B cells, cytokine production, macrophage function and subsequent autoimmune regulation in autoimmune mice.
Prevention of coprophagy modifies magnesium absorption in rats fed with fructo-oligosaccharides
Authors: Ohta Atsutane , Baba Seigo , Ohtsuki Masako , Taguchi Adusa , Adachi Takashi , Hara Hiroshi 
Published: September 2005

AbstractsWe developed a new type of anal cup for prevention of coprophagy and determined whether the absorption of Ca and Mg and the stimulatory effects of feeding fructo-oligosaccharides (FO) on theabsorption of Ca and Mg were altered by prevention of coprophagy in rats. Rats were fed on a FO-free diet or a diet containing 50 g FO/kg for 2 weeks with or without prevention of coprophagy. FO-feeding increased the apparent absorptive ratio of Ca and Mg in rats with or without prevention of coprophagy. However, in the FO-fed groups the absorptive ratio of Mg in rats with prevention of coprophagy was higher than in rats withont prevention of coprophagy. The Ca content of the femur was higher in rats fed on the FO-diet than in rats fed on the FO-free diet both with and without coprophagy. In conclusion, FO-feeding increased the absorption of Ca and Mg in rats both with and without coprophagy. Moreover, prevention of coprophagy enhanced the absorption of Mg in rats fed with FO. Coprophagy has to be considered when the effects of luminal fermentation or mineral absorption are examined in rats
Urea recycling in sheep: effects of intake
Authors: Sarraseca A. , Milne E. , Metcalf M. J. , Lobley G. E. 
Published: September 2005

The effect of intake on urea production, entry into the digestive tract and return of N to the ornithine cycle was studied in four sheep. Each sheep received 0–6, 1–2 and 1.8 × estimated maintenance energy intake quantities of grass pellets for 9 d. After 4 d of adjustment, N balance measurements were conducted between days 5 and 8. From day 7 to day 9 animals were continuously infused, via the jugular vein, with [15N15N]urea and three urine samples were collected at approximately 2h intervals 48–54h after the start of infusion. Total urea and enrichments of [15N15N]- and [14N15N]urea in the urine samples were determined. Urea production was calculated from the isotopic dilution of [15N15N]urea and entry into the gastrointestinal tract (GIT) obtained from the difference between this and urinary urea elimination. Urea which enters the GIT undergoes hydrolysis to liberate NH3which may be reabsorbed and enter the ornithine cycle, in which case the product is [14N15N]urea, based on the probabilities of labelled and unlabelled N providing ureagenic precursors. The quantity of urea-N which returns to the ornithine cycle from the GIT can thus be calculated. Existing models based on this approach yield overestimates of the fate of individual urea molecules due to a failure to allow for multiple recycling of [14N15N]urea species through the GIT. Refinements introduced to cover this resulted in a 33–48 % reduction in calculated return of label for the current study. The present model also predicted that 95 % of the label movements across the GIT could be accommodated by three or fewer entries and returns of urea-N and 99 % by recycling for a maximum of six occasions. Urea-N production increased with intake (P< 0.001) and exceeded digestible N values at all intakes. Urea which entered the digestive tract, both in absolute terms (P< 0.001) and as a proportion of production (0.62, 0.69, 0.73;P= 0.027), increased with intake. The proportion of entry into the digestive tract which was returned to the ornithine cycle remained reasonably constant (0.37–0.41) across all intakes but the absolute amount increased (5.6, 9.2 and 15.0gN/d;P< 0.001) with intake. If allowance is included for losses of15N in faeces then the approach offers a relatively simple means of estimating anabolic reuse of urea by digestive tract micro-organisms and can complement data obtained from the technically more demanding arterio-venous and multiple-isotope techniques used hitherto.Urea: Gastrointestinal tract: [15N]kinetics: Sheep
Further studies on carry-over effects of dietary crude protein and triiodothyronine (T3) in broiler chickens
Authors: Rosebrough R. W. , McMurtry J. P. , Vasilatos-Younken R. 
Published: September 2005

Indian River male broiler chickens growing from 7 to 28 d of age were fed on diets containing either 120 or 210 g crude protein and 0 or 1 mg triiodothyronine (T3)/kg diet to studyin vitrolipogenesis (IVL). In addition, a carry-over period (180 g crude protein/kg diet from 28 to 40 d of age) was used to test the persistence of prior treatment effects. The higher protein level increased, but T3decreased (P< 0.01) growth and feed consumption at 28 d of age. The lower protein level increased (P< 0.05) and T3decreased IVL in 28-d-old chickens. These effects were only sustained for 6 d following the switch to a common diet at 28 d. IVL at 40 d of age was not affected by either crude protein or T3fed during the 7–28 d period. The higher protein level increased plasma insulin-like growth factor-1 during the period from 7 to 28 d; however, this effect lasted for only 6 d following the switch to a common diet. Plasma growth hormone (GH) at 28 d of age was inversely related to dietary protein level. Changing to a common level of crude protein did not change plasma GH values at 12 d, indicating that the nutritional state of the young chicken may affect GH at a later period of life. Metabolic changes noted in this study were rapid and maintained for a short period of time following the feeding of a common diet.Lipogenesis: Dietary protein: Triiodothyronine
AtPEX2 and AtPEX10 Are Targeted to Peroxisomes Independently of Known Endoplasmic Reticulum Trafficking Routes
Authors: Sparkes Imogen Averil , Hawes Chris , Baker Alison 
Published: September 2005

Abstract
Controversy exists in the literature over the involvement of the endoplasmic reticulum (ER) in the delivery of membrane proteins to peroxisomes. In this study, the involvement of the ER in the trafficking of two Arabidopsis (Arabidopsis thaliana) peroxisomal membrane proteins was investigated using confocal laser scanning microscopy of living cells expressing fusions between enhanced yellow fluorescent protein (eYFP) and AtPEX2 and AtPEX10. The fusion proteins were always detected in peroxisomes and cytosol irrespective of the location of the eYFP tag or the level of expression. The cytosolic fluorescence was not due to cleavage of the eYFP reporter from the C-terminal fusion proteins. Blocking known ER transport routes using the fungal metabolite Brefeldin A or expressing dominant negative mutants of Sar1 or RabD2a had no effect on the trafficking of AtPEX2 and AtPEX10 to peroxisomes. We conclude that AtPEX2 and AtPEX10 are inserted into peroxisome membranes directly from the cytosol.
Regulation of the Expression of Intracellular β-Carbonic Anhydrase in Response to CO2 and Light in the Marine Diatom Phaeodactylum tricornutum
Authors: Harada Hisashi , Nakatsuma Daisuke , Ishida Maki , Matsuda Yusuke 
Published: September 2005

Abstract
Cells of the marine diatom Phaeodactylum tricornutum Bohlin (UTEX 642) grown in 5% CO2 were transferred to air-level CO2 in the light or dark and allowed to acclimate to air. No accumulation of the transcript of the P. tricornutumβ-carbonic anhydrase 1 (ptca1) was detected in 5% CO2-grown cells, but ptca1 mRNA accumulated and reached a peak after 6 h acclimation to air but decreased over the next 18 h. A similar accumulation time course was observed in cells air-acclimated in the dark, except that levels of mRNA were &lt;50% those in the light. These results suggest that air-level [CO2] is required to trigger the transcription of ptca1 and that light affects the extent of acclimation. During acclimation to air for 120 h in the light, levels of ptca1 mRNA exhibited a periodic oscillation with a cycle of about 24 h, which, however, was not reflected in protein accumulation levels. A 5′-upstream region from the transcription-start site toward −1,292 bp of ptca1 was cloned by inverse polymerase chain reaction, and 5′-truncations were carried out on this fragment. The truncated promoter regions were fused with the β-glucuronidase gene (uidA) and introduced into P. tricornutum. The promoter fragments, truncated at positions −1,292, −824, −484, −225, and −70 bp, conferred on transformants clear CO2-responsive β-glucuronidase expressions. In contrast, the CO2-responsive regulation was severely impaired or completely abolished by truncations, respectively, at position −50 or −30 bp. These results indicate that critical cis-elements required for CO2-responsive transcription of ptca1 may be located between −70 and −30 bp relative to the transcription start site.
Arabidopsis RAD51C Gene Is Important for Homologous Recombination in Meiosis and Mitosis
Authors: Abe Kiyomi , Osakabe Keishi , Nakayama Shigeki , Endo Masaki , Tagiri Akemi , Todoriki Setsuko , Ichikawa Hiroaki , Toki Seiichi 
Published: September 2005

Abstract
Rad51 is a homolog of the bacterial RecA recombinase, and a key factor in homologous recombination in eukaryotes. Rad51 paralogs have been identified from yeast to vertebrates. Rad51 paralogs are thought to play an important role in the assembly or stabilization of Rad51 that promotes homologous pairing and strand exchange reactions. We previously characterized two RAD51 paralogous genes in Arabidopsis (Arabidopsis thaliana) named AtRAD51C and AtXRCC3, which are homologs of human RAD51C and XRCC3, respectively, and described the interaction of their products in a yeast two-hybrid system. Recent studies showed the involvement of AtXrcc3 in DNA repair and functional role in meiosis. To determine the role of RAD51C in meiotic and mitotic recombination in higher plants, we characterized a T-DNA insertion mutant of AtRAD51C. Although the atrad51C mutant grew normally during vegetative developmental stage, the mutant produced aborted siliques, and their anthers did not contain mature pollen grains. Crossing of the mutant with wild-type plants showed defective male and female gametogeneses as evidenced by lack of seed production. Furthermore, meiosis was severely disturbed in the mutant. The atrad51C mutant also showed increased sensitivity to γ-irradiation and cisplatin, which are known to induce double-strand DNA breaks. The efficiency of homologous recombination in somatic cells in the mutant was markedly reduced relative to that in wild-type plants.
A Lily ASR Protein Involves Abscisic Acid Signaling and Confers Drought and Salt Resistance in Arabidopsis
Authors: Yang Chin-Ying , Chen Yu-Chuan , Jauh Guang Yuh , Wang Co-Shine 
Published: September 2005

Abstract
LLA23, an abscisic acid-, stress-, and ripening-induced protein, was previously isolated from lily (Lilium longiflorum) pollen. The expression of LLA23 is induced under the application of abscisic acid (ABA), NaCl, or dehydration. To provide evidence on the biological role of LLA23 proteins against drought, we used an overexpression approach in Arabidopsis (Arabidopsis thaliana). Constitutive overexpression of LLA23 under the cauliflower mosaic virus 35S promoter confers reduced sensitivity to ABA in Arabidopsis seeds and, consequently, a reduced degree of seed dormancy. Transgenic 35S∷LLA23 seeds are able to germinate under unfavorable conditions, such as inhibitory concentrations of mannitol and NaCl. At the molecular level, altered expression of ABA/stress-regulated genes was observed. Thus, our results provide strong in vivo evidence that LLA23 mediates stress-responsive ABA signaling. In vegetative tissues, it is intriguing that Arabidopsis 35S∷LLA23 stomata remain opened upon drought, while transgenic plants have a decreased rate of water loss and exhibit enhanced drought and salt resistance. A dual function of the lily abscisic acid-, stress-, and ripening-induced protein molecule is discussed.
Cell-to-Cell Movement of Green Fluorescent Protein Reveals Post-Phloem Transport in the Outer Integument and Identifies Symplastic Domains in Arabidopsis Seeds and Embryos
Authors: Stadler Ruth , Lauterbach Christian , Sauer Norbert 
Published: September 2005

Abstract
Developing Arabidopsis (Arabidopsis thaliana) seeds and embryos represent a complex set of cell layers and tissues that mediate the transport and partitioning of carbohydrates, amino acids, hormones, and signaling molecules from the terminal end of the funicular phloem to and between these seed tissues and eventually to the growing embryo. This article provides a detailed analysis of the symplastic domains and the cell-to-cell connectivity from the end of the funiculus to the embryo, and within the embryo during its maturation. The cell-to-cell movement of the green fluorescent protein or of mobile and nonmobile green fluorescent protein fusions was monitored in seeds and embryos of plants expressing the corresponding cDNAs under the control of various promoters (SUC2, SUC3, TT12, and GL2) shown to be active in defined seed or embryo cell layers (SUC3, TT12, and GL2) or only outside the developing Arabidopsis seed (AtSUC2). Cell-to-cell movement was also analyzed with the low-molecular-weight fluorescent dye 8-hydroxypyrene-1,3,6-trisulfonate. The analyses presented identify a phloem-unloading domain at the end of the funicular phloem, characterize the entire outer integument as a symplastic extension of the phloem, and describe the inner integument and the globular stage embryo plus the suspensor as symplastic domains. The results also show that, at the time of hypophysis specification, the symplastic connectivity between suspensor and embryo is reduced or interrupted and that the embryo develops from a single symplast (globular and heart stage) to a mature embryo with new symplastic domains.
Lipid Signaling in Plants. Cloning and Expression Analysis of the Obtusifoliol 14α-Demethylase fromSolanum chacoenseBitt., a Pollination- and Fertilization-Induced Gene with Both Obtusifoliol and Lanosterol Demethylase Activity
Authors: O'Brien Martin , Chantha Sier-Ching , Rahier Alain , Matton Daniel P. 
Published: September 2005

AbstractThe sterol 14α-demethylase (CYP51) is the most widely distributed cytochrome P450 gene family being found in all biological kingdoms. It catalyzes the first step following cyclization in sterol biosynthesis, leading to the formation of precursors of steroid hormones, including brassinosteroids, in plants. Most enzymes involved in the plant sterol biosynthesis pathway have been characterized biochemically and the corresponding genes cloned. Genes coding for enzymes promoting substrate modifications before 24-methylenelophenol lead to embryonic and seed defects when mutated, while mutants downstream the 24-methylenelophenol intermediate show phenotypes characteristic of brassinosteroid mutants. By a differential display approach, we have isolated a fertilization-induced gene, encoding a sterol 14α-demethylase enzyme, named CYP51G1-Sc. Functional characterization of CYP51G1-Sc expressed in yeast (Saccharomyces cerevisiae) showed that it could demethylate obtusifoliol, as well as nontypical plant sterol biosynthetic intermediates (lanosterol), in contrast with the strong substrate specificity of the previously characterized obtusifoliol 14α-demethylases found in other plant species. CYP51G1-Sc transcripts are mostly expressed in meristems and in female reproductive tissues, where they are induced following pollination. Treatment of the plant itself with obtusifoliol induced the expression of the CYP51G1-Sc mRNA, suggesting a possible role of this transient biosynthetic intermediate as a bioactive signaling lipid molecule. Furthermore, treatments of leaves with 14C-labeled obtusifoliol demonstrated that this sterol could be transported in distal parts of the plant away from the sprayed leaves. Arabidopsis (Arabidopsis thaliana) CYP51 homozygous knockout mutants were also lethal, suggesting important roles for this enzymatic step and its substrate in plant development.
Cauliflower mosaic virus, a Compatible Pathogen of Arabidopsis, Engages Three Distinct Defense-Signaling Pathways and Activates Rapid Systemic Generation of Reactive Oxygen Species
Authors: Love Andrew J. , Yun Byung Wook , Laval Valérie , Loake Gary J. , Milner Joel J. 
Published: September 2005

Abstract
We analyzed expression of marker genes for three defense pathways during infection by Cauliflower mosaic virus (CaMV), a compatible pathogen of Arabidopsis (Arabidopsis thaliana), using luciferase reporter transgenes and directly by measuring transcript abundance. Expression of PR-1, a marker for salicylic acid signaling, was very low until 8 d postinoculation and then rose sharply, coinciding with the rise in virus levels. In contrast, as early as 2 h postinoculation, transcriptional up-regulation of GST1—a marker for reactive oxygen species—and PDF1.2—a marker for jasmonic acid/ethylene defense signaling—was detectable in the virus-inoculated leaf and systemically. In parallel with the activation of GST1, H2O2 accumulated locally and systemically in virus- but not mock-inoculated plants. However, in plants inoculated with infectious CaMV DNA rather than virus particles, the onset of systemic luciferase activity was delayed by 24 to 48 h, suggesting that virion structural proteins act as the elicitor. This phenomenon, which we term the rapid systemic response, preceded virus movement from the inoculated leaf; therefore, the systemic signal is not viral. Systemic, but not local, H2O2 accumulation was abolished in rbohDF double mutants and in etr1-1 and ein2-1 mutants, implicating NADPH oxidase and ethylene signaling in the generation and transduction of the response. Ethylene, but not rbohDF mutants, also showed reduced susceptibility to CaMV, whereas in NahG transgenics, virus levels were similar to wild type. These findings implicate reactive oxygen species and ethylene in signaling in response to CaMV infection, but suggest that salicylic acid does not play an effective role.
Selective Attention Modulates Neural Substrates of Repetition Priming and “Implicit” Visual Memory: Suppressions and Enhancements Revealed by fMRI
Authors: Vuilleumier Patrik , Schwartz Sophie , Duhoux Stéphanie , Dolan Raymond J. , Driver Jon 
Published: September 2005

Abstract
Attention can enhance processing for relevant information and suppress this for ignored stimuli. However, some residual processing may still arise without attention. Here we presented overlapping outline objects at study, with subjects attending to those in one color but not the other. Attended objects were subsequently recognized on a surprise memory test, whereas there was complete amnesia for ignored items on such direct explicit testing; yet reliable behavioral priming effects were found on indirect testing. Event-related fMRI examined neural responses to previously attended or ignored objects, now shown alone in the same or mirror-reversed orientation as before, intermixed with new items. Repetition-related decreases in fMRI responses for objects previously attended and repeated in the same orientation were found in the right posterior fusiform, lateral occipital, and left inferior frontal cortex. More anterior fusiform regions also showed some repetition decreases for ignored objects, irrespective of orientation. View-specific repetition decreases were found in the striate cortex, particularly for previously attended items. In addition, previously ignored objects produced some fMRI response increases in the bilateral lingual gyri, relative to new objects. Selective attention at exposure can thus produce several distinct long-term effects on processing of stimuli repeated later, with neural response suppression stronger for previously attended objects, and some response enhancement for previously ignored objects, with these effects arising in different brain areas. Although repetition decreases may relate to positive priming phenomena, the repetition increases for ignored objects shown here for the first time might relate to processes that can produce “negative priming” in some behavioral studies. These results reveal quantitative and qualitative differences between neural substrates of long-term repetition effects for attended versus unattended objects.
Tracing Problem Solving in Real Time: fMRI Analysis of the Subject-paced Tower of Hanoi
Authors: Anderson John R. , Albert Mark V. , Fincham Jon M. 
Published: September 2005

Abstract
Previous research has found three brain regions for tracking components of the ACT-R cognitive architecture: a posterior parietal region that tracks changes in problem representation, a prefrontal region that tracks retrieval of task-relevant information, and a motor region that tracks the programming of manual responses. This prior research has used relatively simple tasks to incorporate a slow event-related procedure, allowing the blood oxygen level-dependent (BOLD) response to go back to baseline after each trial. The research described here attempts to extend these methods to tracking problem solving in a complex task, the Tower of Hanoi, which involves many complex steps of cognition and motor actions in rapid succession. By tracking the activation patterns in these regions, it is possible to predict with intermediate accuracy when participants are planning a future sequence of moves. The article describes a cognitive model in the ACT-R architecture that is capable of explaining both the latency data in move generation and the BOLD responses in these three regions.