bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cytokine Production of In Vitro Stimulated Peripheral Lymphocytes During the Course of Pregnancy and Pseudopregnancy in the Rat
Authors: Faas M. M. , Eenling R. , Van Der Schaaf G. , Moes H. , Heineman M. J. , de Vos P. 
Published: March 2006

Problem  Does maternal lymphocyte cytokine production after in vitro stimulation vary with the stage of pregnancy in the rat?Method of study  Blood samples were taken during the estrus cycle in rats (n = 11). Thereafter, rats were rendered pregnant (n = 6) or pseudopregnant (n = 5) and blood samples were taken at days 4, 8, 11, 15, and 20 of pregnancy and pseudopregnancy. White blood cell (WBC) count was measured and whole blood was stimulated with phorbol 12‐myristate 13‐acetate and calcium ionophore; interferon‐γ (IFNγ) and interleukin‐4 (IL‐4) production as well as (sub)populations of lymphocytes were measured using flow cytometry.Results  We observed an increase of WBC in the second week of pregnancy and a slowly decreasing percentage of lymphocytes during the course of pregnancy. The percentage IFNγ producing T‐lymphocytes after in vitro stimulation was increased during pregnancy (for Th‐lymphocytes only in the second week of pregnancy, for Tc‐lymphocytes at all days). This increased IFNγ production in pregnant T‐lymphocytes was accompanied by an increase during pseudopregnancy, and therefore may result from increased sex hormone concentrations. The percentage IFNγ producing natural killer (NK) cells after in vitro stimulation was decreased on day 20 of pregnancy. No effect of pregnancy or pseudopregnancy was seen on percentage IL‐4 producing lymphocytes after in vitro stimulation.Conclusion  In the rat the IFNγ production after in vitro stimulation varies during pregnancy and is increased, rather than decreased, during pregnancy.
Stratigraphic Control of Flow and Transport Characteristics
Authors: Edington Dwaine , Poeter Eileen 
Published: March 2006

AbstractGround water flow and travel time are dependent on stratigraphic architecture, which is governed by competing processes that control the spatial and temporal distribution of accommodation and sediment supply. Accommodation is the amount of space in which sediment may accumulate as defined by the difference between the energy gradient and the topographic surface. The temporal and spatial distribution of accommodation is affected by processes that change the distribution of energy (e.g., sea level or subsidence). Fluvial stratigraphic units, generated by FLUVSIM (a stratigraphic simulator based on accommodation and sediment supply), with varying magnitudes and causes of accommodation, were incorporated into a hydraulic regime using MODFLOW (a ground water flow simulator), and particles were tracked using MODPATH (a particle‐tracking algorithm). These experiments illustrate that the dominant type of accommodation process influences the degree of continuity of stratigraphic units and thus affects ground water flow and transport. When the hydraulic gradient is parallel to the axis of the fluvial system in the depositional environment, shorter travel times occur in low–total accommodation environments and longer travel times in high–total accommodation environments. Given the same total accommodation, travel times are longer when sea‐level change is the dominant process than those in systems dominated by subsidence.
Heterogeneities in Glaciofluvial Deposits Using an Example from New Hampshire
Authors: Sturgeon Gordon M. , Davis J. Matthew , Linder Ernst , Harter Robert D. 
Published: March 2006

AbstractThe strong influence of subsurface heterogeneity on contaminant migration and in situ remediation calls for an improved understanding of its origins and more efficient methods of characterization. Accordingly, an outcrop study of physical and chemical heterogeneity was conducted in a glaciofluvial deposit in Deerfield, New Hampshire, in order to uncover processes controlling the spatial variation of sediment properties and evaluate the extent to which geologic information can be used to characterize the observed variation. The results indicate that physical and chemical properties at the Deerfield site have distinctly different spatial correlation structures. Lithologic facies explain 31% to 60% of the variation in permeability, dithionite citrate (DC)–extractable manganese, and DC‐extractable aluminum. Lithofacies bounding surfaces do not separate regions of significantly different DC‐extractable iron; instead, 49% of its variation is explained by sediment color. Color also accounts for 34% of the variation in DC‐extractable aluminum and 60% of the variation in DC‐extractable manganese. Strong relationships with sediment facies and/or color enable detailed mapping of permeability, extractable iron, and extractable manganese. Differences in the geometries of iron and manganese enrichment, petrographic observations, and scanning electron microscope analyses indicate that (hydr)oxide grain coatings originated from the postdepositional weathering of biotite and garnet, coupled with local, redox‐driven redistribution of the liberated iron and manganese. The findings suggest that lithofacies and color information can aid the characterization and modeling of heterogeneity at similar carbon‐poor glaciofluvial sites.
Comparison of Local Grid Refinement Methods for MODFLOW
Authors: Mehl Steffen , Hill Mary C. , Leake Stanley A. 
Published: March 2006

AbstractMany ground water modeling efforts use a finite‐difference method to solve the ground water flow equation, and many of these models require a relatively fine‐grid discretization to accurately represent the selected process in limited areas of interest. Use of a fine grid over the entire domain can be computationally prohibitive; using a variably spaced grid can lead to cells with a large aspect ratio and refinement in areas where detail is not needed. One solution is to use local‐grid refinement (LGR) whereby the grid is only refined in the area of interest. This work reviews some LGR methods and identifies advantages and drawbacks in test cases using MODFLOW‐2000. The first test case is two dimensional and heterogeneous; the second is three dimensional and includes interaction with a meandering river. Results include simulations using a uniform fine grid, a variably spaced grid, a traditional method of LGR without feedback, and a new shared node method with feedback. Discrepancies from the solution obtained with the uniform fine grid are investigated. For the models tested, the traditional one‐way coupled approaches produced discrepancies in head up to 6.8% and discrepancies in cell‐to‐cell fluxes up to 7.1%, while the new method has head and cell‐to‐cell flux discrepancies of 0.089% and 0.14%, respectively. Additional results highlight the accuracy, flexibility, and CPU time trade‐off of these methods and demonstrate how the new method can be successfully implemented to model surface water–ground water interactions.
Food and activity in out of school hours care in Victoria
Authors: THOMPSON Ernestine , COOPER Catherine , FLANAGAN Claire , CRAWFORD David , WORSLEY Anthony 
Published: March 2006

AbstractObjective:  To describe characteristics of the Victorian out of school hours care (OSHC) sector to assess its potential role in promoting healthy lifestyles to children and their families.Design:  Written questionnaires were sent to 1100 Victorian OSHC programs to collect information about the services, foods and activities offered to children, the training and resources utilised by staff and the type of information sent home to parents/guardians.Subjects:  A total of 426 Victorian OSHC coordinators completed questionnaires in the present descriptive study (39% response rate).Setting:  Out of school hours care provides care for 5–12 years olds before school, after school and/or during school holidays.Results:  Over 80% of coordinators reported offering fruit, breads, cereals, and milk and dairy products. One‐third offer vegetables as part of meals or snacks. One‐third reported offering cakes, biscuits and/or slices, and chips and/or pastries. About 17% reported offering water, whereas 24% reported offering cordial/soft drinks and fruit juice. Cooking was offered as an after‐school activity by about half of those surveyed. Active games were common (62%) as were indoor active games and sports (36%). Sedentary activities were also commonplace (37–51%). Only about 30% of OSHC coordinators had participated in nutrition and/or physical activity training in the previous two years. Few OSHC programs sent home health information to parents/guardians.Conclusion and application:  Opportunities exist to help Victorian OSHC programs with nutrition and physical activity information, resources and training. Although the findings of the present study are specific to Victoria, they highlight the potential role of the growing OSHC sector to help improve the health of Australian children.
Eating breakfast and its impact on children's daily diet
Authors: WILSON Noela C. , PARNELL Winsome R. , WOHLERS Mark , SHIRLEY Philippa M. 
Published: March 2006

AbstractObjective:  To describe the impact of breakfast eating on the nutrient intakes of New Zealand children aged 5–14 years.Design:  Secondary data analysis of a cross‐sectional national survey.Subjects:  A total of 3275 children aged 5–14 years.Setting:  Dietary data were collected primarily in the homes of the children.Main outcome measures:  ‘Breakfast consumption’ was based on whether any food items were consumed between 6 and 9 a.m. from 24‐hour diet recall data. Nutrient intake was also based on 24‐hour diet recall.Data analyses:  Demographic profile of breakfast eaters was determined. Difference in daily nutrient intakes between breakfast and non‐breakfast eaters was determined.Results:  In total, 84% of New Zealand children reported eating breakfast. Younger children were more likely to eat breakfast than older children. Breakfast habits differed between Māori, Pacific and ‘New Zealand European & Others’ children. When intakes were adjusted for the demographic variables that significantly affected breakfast consumption patterns, daily nutrient intake of children who ate breakfast compared with those who did not, was significantly better. This was true for all ethnic groups. Cereal (including cold, ready‐to‐eat and cooked) was the most common breakfast food.Conclusion:  Although the majority of New Zealand children consume breakfast, a significant improvement in daily nutrient intake could be achieved for children of all ethnic groups who currently do not consume breakfast.
Saccharomyces cerevisiae
Sof1p Associates with 35S Pre-rRNA Independent from U3 snoRNA and Rrp5p
Authors: Bax Ralph , Vos Harmjan R. , Raué Hendrik A. , Vos Jan C. 
Published: March 2006

ABSTRACT

Sof1p is a
trans
-acting protein that is essential for biogenesis of the 40S ribosomal subunits in the yeast
Saccharomyces cerevisiae
. Because of its involvement in the early cleavage steps of precursor rRNA, its interaction with Nop1p and its ability to coprecipitate U3 snoRNA, Sof1p has so far been regarded as a protein that is specific to the U3 snoRNP. To determine whether a site exists within U3 snoRNA with which Sof1p directly or indirectly associates, we studied the ability of ProtA-tagged Sof1p to coimmunoprecipitate mutant versions of U3 snoRNA. None of the tested mutations had a significant effect on the recovery of mutant U3 from cell extracts. Further coimmunoprecipitation experiments, using cells that could be genetically depleted for either Sof1p or U3 snoRNA demonstrated that the two factors associate independently of each other with the 35S precursor RNA. Indeed, association between Sof1p and U3 snoRNA was abolished in cells in which 35S pre-rRNA transcription was blocked. Finally, we found that an overall reduction in the levels of box C/D snoRNPs by genetic depletion of the common Nop58p protein did not affect coprecipitation of 35S pre-rRNA by Sof1p. From these data, we conclude that Sof1p does not assemble into the 90S preribosome as part of the U3, or any other box C/D, snoRNP. The early and independently assembling
trans-
acting factor Rrp5p also proved to be dispensable for assembly of Sof1p.
Fission Yeast Rho5p GTPase Is a Functional Paralogue of Rho1p That Plays a Role in Survival of Spores and Stationary-Phase Cells
Authors: Rincón Sergio A. , Santos Beatriz , Pérez Pilar 
Published: March 2006

ABSTRACT

The Rho GTPase family and their effectors are key regulators involved in many eukaryotic cell functions related to actin organization and polarity establishment.
Schizosaccharomyces pombe
Rho1p is essential, directly activates the (1,3)-β-
d
-glucan synthase, and participates in regulation of cell wall growth and morphogenesis. Here we describe the characterization of the fission yeast Rho5p GTPase, highly homologous to Rho1p, sharing 86% identity and 95% similarity. Overexpression of the hyperactive allele
rho5-G15V
causes a morphological effect similar to that of
rho1-G15V
, but the penetrance is significantly lower, and overexpression of the dominant-negative allele
rho5-T20N
causes lysis like that of
rho1-T20N
. Importantly, overexpression of
rho5
+
but no other
rho
genes is able to rescue the lethality of
rho1
Δ cells. Shutoff experiments indicated that Rho5p can replace Rho1p, but it is not as effective in maintaining cell wall integrity or actin organization.
rho5
+
expression is hardly detected during log-phase growth but is induced under nutritional starvation conditions.
rho5
Δ cells are viable and do not display any defects during logarithmic growth. However, when
rho1
+
expression is repressed during stationary phase,
rho5
Δ cells display reduced viability. Ascospores lacking Rho5p are less resistant to heat or lytic enzymes than wild-type spores. Moreover, h
90
mutant strains carrying the hyperactive
rho5-G15V
or the dominant-negative
rho5-T20N
alleles display severe ascospore formation defects. These results suggest that Rho5p functions in a way similar to, but less efficient than, Rho1p, plays a nonessential role during stationary phase, and participates in the spore wall formation.
Transcriptional Regulation of
xyn1
, Encoding Xylanase I, in
Hypocrea jecorina
Authors: Rauscher Roman , Würleitner Elisabeth , Wacenovsky Christian , Aro Nina , Stricker Astrid R. , Zeilinger Susanne , Kubicek Christian P. , Penttilä Merja , Mach Robert L. 
Published: March 2006

ABSTRACT

Two major xylanases (XYN I and XYN II) of the filamentous fungus
Hypocrea jecorina
(
Trichoderma reesei
) are simultaneously expressed during growth on xylan but respond differently to low-molecular-weight inducers. In vivo footprinting analysis of the xylanase1 (
xyn1
) promoter revealed three different nucleotide sequences (5′-

GGCTAA

ATGCGACATC

TTAGCC

-3′ [an inverted repeat of GGCTAA spaced by 10 bp], 5′-CCAAT-3′, and 5′-

GGGGTC

TA

GACCCC

-3′ [equivalent to a double Cre1 site]) used to bind proteins. Binding to the Cre1 site is only observed under repressed conditions, whereas binding to the two other motifs is constitutive. Applying heterologously expressed components of the
H. jecorina
cellulase regulators Ace1 and Ace2 and the xylanase regulator Xyr1 suggests that Ace1 and Xyr1 but not Ace2 contact both GGCTAA motifs.
H. jecorina
transformants containing mutated versions of the
xyn1
promoter, leading to elimination of protein binding to the left or the right GGCTAA box revealed either strongly reduced or completely eliminated induction of transcription. Elimination of Cre1 binding to its target released the basal transcriptional level from glucose repression but did not influence the inducibility of
xyn1
expression. Mutation of the CCAAT box prevents binding of the Hap2/3/5 complex in vitro and is partially compensating for the loss of transcription caused by the mutation of the right GGCTAA box. Finally, evidence for a competition of Ace1 and Xyr1 for the right GGCTAA box is given. These data prompted us to hypothesize that
xyn1
regulation is based on the interplay of Cre1 and Ace1 as a general and specific repressor with Xyr1 as transactivator.
Analysis of the Phosphoproteome of
Chlamydomonas reinhardtii
Provides New Insights into Various Cellular Pathways
Authors: Wagner Volker , Geßner Gunther , Heiland Ines , Kaminski Marc , Hawat Susan , Scheffler Kai , Mittag Maria 
Published: March 2006

ABSTRACT

The unicellular flagellated green alga
Chlamydomonas reinhardtii
has emerged as a model organism for the study of a variety of cellular processes. Posttranslational control via protein phosphorylation plays a key role in signal transduction, regulation of gene expression, and control of metabolism. Thus, analysis of the phosphoproteome of
C. reinhardtii
can significantly enhance our understanding of various regulatory pathways. In this study, we have grown
C. reinhardtii
cultures in the presence of an inhibitor of Ser/Thr phosphatases to increase the phosphoprotein pool. Phosphopeptides from these cells were enriched by immobilized metal-ion affinity chromatography and analyzed by nano-liquid chromatography-electrospray ionization-mass spectrometry (MS) with MS-MS as well as neutral-loss-triggered MS-MS-MS spectra. In this way, we were able to identify 360 phosphopeptides from 328 different phosphoproteins of
C. reinhardtii
, thus providing new insights into a variety of cellular processes, including metabolic and signaling pathways. Comparative analysis of the phosphoproteome also yielded new functional information on proteins controlled by redox regulation (thioredoxin target proteins) and proteins of the chloroplast 70S ribosome, the centriole, and especially the flagella, for which 32 phosphoproteins were identified. The high yield of phosphoproteins of the latter correlates well with the presence of several flagellar kinases and indicates that phosphorylation/dephosphorylation represents one of the key regulatory mechanisms of eukaryotic cilia. Our data also provide new insights into certain cilium-related mammalian diseases.
Regulation of Salt Tolerance byTorulaspora delbrueckiiCalcineurin Target Crz1p
Authors: Hernandez-Lopez Maria Jose , Panadero Joaquin , Prieto Jose Antonio , Randez-Gil Francisca 
Published: March 2006

ABSTRACTRecently, the academic interest in the yeastTorulaspora delbrueckiihas increased notably due to its high resistance to several types of stress, including salt and osmotic imbalance. However, the molecular mechanisms underlying these unusual properties are poorly understood. InSaccharomyces cerevisiae, the high-salt response is mediated by calcineurin, a conserved Ca2+/calmodulin-modulated protein phosphatase that regulates the transcriptional factor Crz1p. Here, we cloned theT. delbrueckiiTdCRZ1gene, which encodes a putative zinc finger transcription factor homologue to Crz1p. Consistent with this, overexpression of TdCRZ1enhanced the salt tolerance ofS. cerevisiaewild-type cells and suppressed the sensitivity phenotype ofcnb1Δ andcrz1Δ mutants to monovalent and divalent cations. However,T. delbrueckiicells lacking TdCrz1p showed phenotypes distinct from those previously observed inS. cerevisiae crz1Δ mutants. Quite remarkably, Tdcrz1-null cells were insensitive to high Na+and were more Li+tolerant than wild-type cells. Clearly, TdCrz1p was not required for the salt-induced transcriptional activation of the TdENA1gene, encoding a putative P-type ATPase homologue to the mainS. cerevisiaeNa+pumpENA1. Furthermore,T. delbrueckiicells were insensitive to the immunosuppressive agents FK506 and cyclosporine A, both in the presence and in the absence of NaCl. Signaling through the calcineurin/Crz1 pathway appeared to be essential only on high-Ca2+/Mn2+media. Hence,T. delbrueckiiandS. cerevisiaediffer in the regulatory circuits and mechanisms that drive the adaptive response to salt stress.
Role of a Mitogen-Activated Protein Kinase Cascade in Ion Flux-Mediated Turgor Regulation in Fungi
Authors: Lew Roger R. , Levina Natalia N. , Shabala Lana , Anderca Marinela I. , Shabala Sergey N. 
Published: March 2006

ABSTRACTFungi normally maintain a high internal hydrostatic pressure (turgor) of about 500 kPa. In response to hyperosmotic shock, there are immediate electrical changes: a transient depolarization (1 to 2 min) followed by a sustained hyperpolarization (5 to 10 min) prior to turgor recovery (10 to 60 min). Using ion-selective vibrating probes, we established that the transient depolarization is due to Ca2+influx and the sustained hyperpolarization is due to H+efflux by activation of the plasma membrane H+-ATPase. Protein synthesis is not required for H+-ATPase activation. Net K+and Cl−uptake occurs at the same time as turgor recovery. The magnitude of the ion uptake is more than sufficient to account for the osmotic gradients required for turgor to return to its original level. Two osmotic mutants,os-1andos-2, homologs of a two-component histidine kinase sensor and the yeast high osmotic glycerol mitogen-activated protein (MAP) kinase, respectively, have lower turgor than the wild type and do not exhibit the sustained hyperpolarization after hyperosmotic treatment. Theos-1mutant does not exhibit all of the wild-type turgor-adaptive ion fluxes (Cl−uptake increases, but net K+flux barely changes and net H+efflux declines) (os-2was not examined). Bothosmutants are able to regulate turgor but at a lower level than the wild type. Our results demonstrate that a MAP kinase cascade regulates ion transport, activation of the H+-ATPase, and net K+and Cl−uptake during turgor regulation. Other pathways regulating turgor must also exist.
Lipid Rafts in
Cryptococcus neoformans
Concentrate the Virulence Determinants Phospholipase B1 and Cu/Zn Superoxide Dismutase
Authors: Siafakas A. Rosemary , Wright Lesley C. , Sorrell Tania C. , Djordjevic Julianne T. 
Published: March 2006

ABSTRACT

Lipid rafts have been identified in the membranes of mammalian cells, the yeast
Saccharomyces cerevisiae
, and the pathogenic fungus
Candida albicans
. Formed by a lateral association of sphingolipids and sterols, rafts concentrate proteins carrying a glycosylphosphatidylinositol (GPI) anchor. We report the isolation of membranes with the characteristics of rafts from the fungal pathogen
Cryptococcus neoformans
. These characteristics include insolubility in Triton X-100 (TX100) at 4°C, more-buoyant density within a sucrose gradient than the remaining membranes, and threefold enrichment with sterols. The virulence determinant phospholipase B1 (PLB1), a GPI-anchored protein, was highly concentrated in raft membranes and could be displaced from them by treatment with the sterol-sequestering agent methyl-β-cyclodextrin (MβCD). Phospholipase B enzyme activity was inhibited in the raft environment and increased 15-fold following disruption of rafts with TX100 at 37°C. Treatment of viable cryptococcal cells in suspension with MβCD also released PLB1 protein and enzyme activity, consistent with localization of PLB1 in plasma membrane rafts prior to secretion. The antioxidant virulence factor Cu/Zn superoxide dismutase (SOD1) was concentrated six- to ninefold in raft membrane fractions compared with nonraft membranes, whereas the cell wall-associated virulence factor laccase was not detected in membranes. We hypothesize that raft membranes function to cluster certain virulence factors at the cell surface to allow efficient access to enzyme substrate and/or to provide rapid release to the external environment.