bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimization of the Human Adenosine A2a Receptor Yields in Saccharomyces cerevisiae
Authors: Wedekind Alison , O'Malley Michelle A. , Niebauer Ronald T. , Robinson Anne S. 
Published: July 2006

AbstractG‐protein coupled receptors (GPCRs) have been implicated in many human diseases and have emerged as important drug targets. Despite their medical relevance, knowledge about GPCR structure is limited, mainly due to difficulties associated with producing large amounts of functional protein and isolating this protein in functional form. However, our previous results indicate that when the human adenosine A2a receptor (A2aR) is expressed in Saccharomyces cerevisiae, high yields can be achieved. In light of these initial results and in anticipation of future purification efforts, experiments were conducted to optimize the system for maximum total protein yield. Emphasis was placed on not only producing large quantities of A2aR in each cell but also achieving high cell density in batch culture. Therefore, temperature, media pH, inducer concentration in the media, and induction cell density were tested for their effects on both cell growth (as measured by optical density, OD600) and per cell A2aR expression levels. For these studies, the A2aR expression levels were determined using a previously described A2aR‐green fluorescent protein (GFP) fusion, so that expression could be monitored by fluorescence. Overall the data indicate that at late times (∼60 h of expression) approximately 75% higher total batch protein yields can be achieved using lower expression temperatures or 60% higher using elevated induction cell density. The highest yields correspond to approximately 28 mg per liter of culture of total A2aR. Amounts of functional receptor were shown to increase on a per cell basis by decreasing expression temperature up to 25 h of expression, but at late time points (∼60 h) functional yields did not appreciably improve. When compared to other reports of GPCR expression in yeast it is clear that this system is among those producing the highest GPCR protein yields per culture both before and after optimization.
Prevalence of EGG Derangement in Newly Diagnosed Type 1 Diabetes in Childhood
Authors: Toporowska‐Kowalska Ewa , Wąsowska‐Królikowska Krystyna , Szadkowska Agnieszka , Młynarski Wojciech , Bodalski J 
Published: July 2006

ABSTRACTObjective:To evaluate gastric myoelectrical activity in children with newly diagnosed type 1 diabetes melliltus (T1DM) in relation to blood glucose control and visceral neuropathy.Methods:Percutaneous electrogastrograpy (EGG) was performed on 42 children (20 F; mean age 12.9 ± 3.1 years) with T1DM of <1 year's duration and on 35 healthy controls (18 F; mean age 13.4 ± 3.6 years). After overnight fasting, a 30‐minute EGG recording was followed by test meal consumption and then a 60‐minute postprandial EGG aquisition. Fasting and postprandial periods were analyzed for gastric dysrhythmias, dominant frequency (DF) and additional parameters. In T1DM patients, HbA1c and blood glucose levels were measured and tests for visceral neuropathy were performed.Results:In 41 T1DM patients (98%), cardiovascular neuropathy tests were negative. In 12 of those patients (29%) and in 32 healthy controls (91%), electrogastrograms were normal. The percentages of fasting and postprandial gastric dysrhythmias were significantly higher in T1DM patients compared to controls (P < 0,05). In T1DM children after feeding, some normalization of gastric myoelectrical rhythm was observed: normogastria increased nearly 2‐fold to 72.6 ± 22.9% and bradygastria decreased to 20.8 ± 20.4% from 52.3 ± 32.4% (P < 0.05). The percentages of fasting bradygastria and normogastria were correlated with glycemia level (r = −0.55 and r = 0.51, respectively; P < 0.05), as was postprandial DF (r = 0.41; P < 0.05). There was no correlation between HbA1c levels and EGG parameters.Conclusions:Derangement of the gastric myoelectrical activity is present in 71% of children with early stage T1DM. Glucose levels influence gastric myoelectrical activity, whereas long‐term glucose control (HbA1c level) does not correlate with EGG parameters.
Alanine Amino Transferase Concentrations Are Linked to Folate Intakes and Methylenetetrahydrofolate Reductase Polymorphism in Obese Adolescent Girls
Authors: Frelut Marie‐Laure , Emery‐Fillon Nathalie , Guilland Jean‐Claude , Dao Hunh Han , de Courcy Geneviève Potier 
Published: July 2006

ABSTRACTObjective:The objective of this study was to investigate the consequences of low dietary folate intake and the impact of the 677 C→T methylenetetrahydrofolate reductase (MTHFR) common mutation on liver function in obese adolescents.Methods:Fifty‐seven obese girls (BMI = 36.1 ± 6.0 kg/m2) aged 14.1 ± 1.5 years were included before starting a weight reduction program. Dietary intakes for folate were assessed by means of an adapted food frequency questionnaire (n = 50). Liver enzymes, plasma lipids, glucose metabolism parameters, ferritin, homocysteine and erythrocyte folate content were measured in plasma or blood obtained under fasting conditions. The MTHFR 677 C→T polymorphism, which is associated with decreased enzyme activity, was determined using PCR. Body composition was assessed using dual x‐ray absorptiometry.Results:Twenty‐three subjects were heterozygote (CT) for the mutation and 5 were homozygote (TT). An increase in alanine amino transferase (ALT) and ALT/aspartate aminotransferase ratio was associated with the mutation (F = 4.46, P = 0.016 and F = 5.92, P = 0.0049, respectively). Alanine amino transferase was correlated negatively to folate intake (r = −0.32, P = 0.024) (n = 50) and positively to homocysteine concentrations (r = 0.30, P = 0.025). Body composition was similar among the 3 genotypic groups. Ferritin was also correlated to ALT concentrations of the entire group (P = 0.009).Conclusion:Our data suggest that folate intake and the MTHFR polymorphism represent a part of the link between antioxidant status and liver disease in obese adolescent girls.
Hepatitis C in Children
Authors: Rumbo Carolina , Fawaz Rima L. , Emre Sukru H. , Suchy Frederick J. , Kerkar Nanda , Morotti Raffaella A. , Shneider Benjamin L. 
Published: July 2006

ABSTRACTIntroduction:Chronic hepatitis C virus (HCV) infection affects 0.3% of children in the United States, and the general impression is that it has a benign course in childhood. We analyzed a pediatric population with chronic HCV in a quaternary referral center.Material and Methods:This is a retrospective clinical review comprising all patients with chronic HCV referred to the Pediatric Liver/Liver Transplant Program between January 1999 and December 2004.Results:Ninety‐one patients (52% female; mean age, 9 years) were assessed. Eight‐three percent of the patients were genotype 1. Twenty‐one patients received/are receiving interferon and ribavirin for chronic HCV (treatment indications‐advanced disease, 9; clinical trial, 6; genotype 2, 2; social, 2; prerenal transplant, 1). Eight (53%) of 15 patients, who have completed therapy and follow‐up, achieved sustained viral response. Seven of 91 patients had cirrhosis at presentation (mean age, 11.7 years). Four underwent liver transplantation, all experienced HCV recurrence, 2 died, 1 was retransplanted, and 1 has compensated cirrhosis.Conclusion:Although, in general, HCV in children has a slow progression, there are cases with an accelerated course and early development of cirrhosis requiring liver transplant. Hepatitis C virus recurs universally after transplant, and its prognosis is usually poor; therefore, the most promising long‐term approach is to clear this infection before transplantation.
Slicing a protease: Structural features of the ATP‐dependent Lon proteases gleaned from investigations of isolated domains
Authors: Rotanova Tatyana V. , Botos Istvan , Melnikov Edward E. , Rasulova Fatima , Gustchina Alla , Maurizi Michael R. , Wlodawer Alexander 
Published: July 2006

AbstractATP‐dependent Lon proteases are multi‐domain enzymes found in all living organisms. All Lon proteases contain an ATPase domain belonging to the AAA+superfamily of molecular machines and a proteolytic domain with a serine‐lysine catalytic dyad. Lon proteases can be divided into two subfamilies, LonA and LonB, exemplified by theEscherichia coliandArchaeoglobus fulgidusparalogs, respectively. The LonA subfamily is defined by the presence of a large N‐terminal domain, whereas the LonB subfamily has no such domain, but has a membrane‐spanning domain that anchors the protein to the cytoplasmic side of the membrane. The two subfamilies also differ in their consensus sequences. Recent crystal structures for several individual domains and sub‐fragments of Lon proteases have begun to illuminate similarities and differences in structure–function relationships between the two subfamilies. Differences in orientation of the active site residues in several isolated Lon protease domains point to possible roles for the AAA+domains and/or substrates in positioning the catalytic residues within the active site. Structures of the proteolytic domains have also indicated a possible hexameric arrangement of subunits in the native state of bacterial Lon proteases. The structure of a large segment of the N‐terminal domain has revealed a folding motif present in other protein families of unknown function and should lead to new insights regarding ways in which Lon interacts with substrates or other cellular factors. These first glimpses of the structure of Lon are heralding an exciting new era of research on this ancient family of proteases.
Plane xanthomata associated with multiple myeloma and hyperlipoproteinaemia
Authors: MARIEN K.J.C. , SMEENK G. 
Published: July 2006

SUMMARY
A case of plane xanthomatosis associated with multiple myeloma and hyperlipoproteinaemia in a 62-year-old woman is reported. The patient had IgG type lambda paraproteinaemia and type II A hyperlipoproteinaemia.
The IgG paraprotein showed binding activity against high-density lipoproteins. It could not be demonstrated that these paraprotein-lipoprotein complexes were responsible for the hyperlipidaemia.
Microchemical analysis of pathological skin demonstrated a high content of triglycerides, similar to that in eruptive xanthomata. No correlation was found between the lipid composition of the xanthomatous skin and the serum lipid composition.
The results obtained with an in vitro culture method showed that the paraprotein present in the patient's serum was synthesized in the bone marrow but not in the normal or pathological skin.
A severe ‘stasis eczema’, associated with low plasma zinc, treated successfully with oral zinc
Authors: OWENS C.W.I. , AL-KHADER A.A. , JACKSON M.J. , PRICHARD B.N.C. 
Published: July 2006

SUMMARY
We describe a case of non-ulcerating severe stasis eczema in an elderly female associated with a low plasma zinc and which responded to treatment with oral supplements. The dermatological changes were not accompanied by oedema and were most marked over the lower legs and ankles, with patchy erythematous lesions extending to the inner thighs, over the dorsal surface of both hands and the forearms. There was some excoriation and a degree of lichenification. These lesions were intensely pruritic and resolved almost completely following treatment with oral zinc sulphate (220 mg daily) on two separate occasions. Histological appearances of biopsy material included those of stasis eczema but there was also a marked degree of parakeratosis.
The cause of the low plasma zinc was not identified.
Packing of sands
Authors: PANAYIOTOPOULOS K. P. , MULLINS C. E. 
Published: July 2006

SUMMARYThe packing of sands was studied over a range of moisture contents using both static loads and impacts from a Bruce compactor. Particle shape and particle size distribution were found to determine the maximum and minimum void ratio to which a sand would pack. For narrowly graded sands, air‐dry and nearly saturated sands were always found to pack more closely under a given load than the same sand at any other moisture content. There was practically no variation of packing with moisture content over a wide range of intermediate moisture contents. The bulk density attained after impact loading depended on the bulk density prior to impact and increased with the logarithm of the number of impacts. An attempt is made to give a physical explanation for these results and to relate results obtained by static loading and Bruce compaction.
Fused protein of δPKC activation loop and PDK1‐interacting fragment (δAL‐PIF) functions as a pseudosubstrate and an inhibitory molecule for PDK1 when expressed in cells
Authors: Seki Takahiro , Irie Naoki , Nakamura Kyoko , Sakaue Hiroshi , Ogawa Wataru , Kasuga Masato , Yamamoto Hideyuki , Ohmori Shiho , Saito Naoaki , Sakai Norio 
Published: July 2006

To elucidate the role of 3‐phosphoinositide‐dependent protein kinase‐1 (PDK1) in cellular signaling, we constructed and expressed a pseudosubstrate of PDK1, designated as δAL‐PIF, and characterized its properties in cultured cells. δAL‐PIF consists of two fused proteins of the protein kinase Cδ (δPKC) activation loop (δAL) and PDK1‐interacting fragment (PIF). The phosphorylation of δAL‐PIF was detected with anti‐δPKC phospho‐Thr505‐specific antibody and was increased in proportion to the expression level of co‐expressed GST‐PDK1, indicating that it acts as a pseudosubstrate of PDK1. In cells expressing δAL‐PIF, basal phosphorylation level at the activation loop of PKBα, δPKC and γPKC was reduced, compared with that in control cells, suggesting that δAL‐PIF functions as an inhibitory molecule for PDK1. δAL‐PIF affected the stability, translocation and endogenous activity of PKCs. These effects of δAL‐PIF on γPKC properties were confirmed by investigation using conditioned PDK1 knockout cells. Furthermore, apoptosis frequently occurred in cells expressing δAL‐PIF for 3 days. These findings revealed that δAL‐PIF served as an effective pseudosubstrate and an inhibitory molecule for PDK1, suggesting that this molecule can be used as a tool for investigating PDK‐mediated cellular functions as well as being applicable for anti‐cancer therapy.
The effect of planting Pinus pinaster Ait. on populations of soil microarthropods and on litter decomposition at Gnangara, Western Australia
Authors: SPRINGETT JOSEPHINE A. 
Published: July 2006

AbstractLitter decomposition rates and the population densities of soil microarthropods were measured in three Pinus pinaster stands thirty‐one, twenty‐three and eighteen years old, and on an area of native vegetation on sandy soil at Gnangara, W.A. Litter decomposition was faster in the soil than within the litter layer and was slowest at the litter surface. Decomposition was rapid in cool wet seasons and slow in hot, dry summers. Microarthropod population densities were similar on all sites (77–100 × 103/m2) but species diversity was greatest under native vegetation and least under the youngest pine stand. The impoverished soil micro‐fauna of the pine stands is unable to decompose pine or sclerophyll litter as fast as the full complement of soil microfauna in native vegetation.
Population characteristics of Australian leafrollers (Epiphyas spp., Lepidoptera) infesting orchards
Authors: GEIER P. W. , SPRINGETT B. P. 
Published: July 2006

Abstract Light‐brown apple moths (LBAMs) are Australian leafrollers of the genus Epiphyas, capable of infesting orchards and other horticultural crops. Currently, five species are recognized, two of which, E. postvittana and E. pulla, can be serious economic pests. By means of principal‐components and group‐average cluster analyses applied to six parameters of demographic performance, two forms suspected of being interspecific hybrids were tested comparatively with possible parent species, and were found to be indistinguishable from E. postvittana. The frequency distribution of cornuti, a structural feature of the male genitalia used in identification, was investigated experimentally in the two economic species and their hybrids. The numerical variability of this character was shown to be much greater than had been recognized previously. It was found also that, in E. postvittana, cornuti frequencies may change in response to environmental influences. Hybrids tended to have cornuti numbers intermediate between those of their progenitors.LBAMs seem to be undergoing rapid evolutionary change in response to man‐induced alterations in the environment, and represent a hazard to horticulture not only in Australia, but possibly also in any temperate or sub‐tropical region to which they might gain access overseas. The situation would justify undertaking a systematic, Australia‐wide, survey of these and related leafrollers.
Physical structure of an ant community in semi‐arid Australia
Authors: BRIESE D. T. , MACAULEY B. J. 
Published: July 2006

AbstractA study was carried out on the physical structure of an ant community in a semi‐arid habitat of southern New South Wales. Thirty‐seven species were collected from the area, and the relative abundance and spatial distribution of colonies of these species were determined in two plots, one in an area dominated by saltbush (Atriplex vesicaria), the other in an area where saltbush had been removed by overgrazing, leaving a simple grassland.The composition and community structure of the populations were found to be little affected by vegetation, and there were no marked differences between the ant faunas of the two areas.Analyses of spatial distribution of the ant colonies showed a variety of patterns, ranging from aggregated to overdispersed, both within and between species. It is suggested that the contemporary structure of an ant community results in the main from processes involving aggressive interactions, determined by the intrinsic properties of the constituent species.
Microvariation in the fauna of a sublittoral sand bank, Moreton Bay, Queensland
Authors: POINER I. R. 
Published: July 2006

AbstractBenthic macrofauna was sampled from Naval Reserve Bank, Moreton Bay, Queensland, using an 0.05 m2 van Veen grab, and data were used to investigate spatial micropatterning. Samples were taken within a 5 × 6 square sampling grid (total area 730 in2) with an intersampling distance of 6 m. Samples were taken in duplicate on each occasion at 2‐inonth intervals. Particle size of sediments and depth data were also collected. Data on other abiotic factors such as temperature, salinity and currents were inferred.Sampling gave data for 131 species. Hierarchical numerical classificatory techniques were employed to obtain (a) spatial patterns (site‐groups) based on biotic data, and (b) species‐groups which characterize the above site groups. Species diversity (SH) species richness (S), species evenness (J’) and individual species diversity (I) indices were computed for the total data set for each site with the species summated over the sampling times.A selected number of species were used in the classification. The spatial patterns were well defined but the species‐groups categorizing them were somewhat confused. Species diversity indices were found to be of little aid in the interpretation of the site patterns or in generating alternative hypotheses.
The comparative ecology of ten species of honeyeaters in South Australia
Authors: FORD HUGF A. , PATON DAVID C. 
Published: July 2006

AbstractWe describe the habitats and feeding sites used by ten species of honeyeaters in the Mount Lofty Ranges near Adelaide, South Australia.Five of the species have relatively short beaks and feed chiefly on insects gleaned from leaves and bark or captured in the air. They also visit the flowers of Eucalyptus and occasionally of other plants. Species in the same genus occupy different habitats. The five longer‐beaked species feed more often onflowers of a wider variety including Eucalyptus, tubular flowers of the heaths and the inflorescences of bottle‐brushes. They also feed on insects, most of which they capture in the air. Most of these species overlap broadly in habitat and thus form a guild of species which are very similar in their overall ecology.
Aggregation of sublittoral macrobenthos in Moreton Bay, Queensland
Authors: STEPHENSON W. , COOK S. D. 
Published: July 2006

AbstractQuintuplicate samples of macrobenthos were collected by an 0.1 m2 Smith‐McIntyre grab from six selected sites in Moreton Bay at 8‐week intervals on twelve occasions. This is part of a continuing study of time changes in the benthos.The present paper deals with the‘withinfives’data, mostly on a species basis. We show that there is, for most species, a close power curve relationship between variances (withinfives) and means (of fives): here v = am where V is variance, m is mean, and a and b are constants. Following Taylor's (1961, 1971) initial interpretations b is a measure of aggregation, although a values also have interpretive importance. Of eight‐seven species studied there is a spectrum from highly aggregated (c. 65% of total) to random (c. 25%) to spaced (c. l0%). There is a comparable spectrum of transformations to produce variance stabilizing in the data.Power curve fitting also applies to total site populations (n) where b is 1.977 and data require log transformation, and to species densities (s) where b is 1.342 and data require cube‐root transformation.The data are not entirely suitable for investigating the topographic scale of patchiness of species within the 20 m‘within‐fives’traverses. A predominant patch width of 30 m or more was revealed.
Time‐patterns of macrobenthic species in Moreton Bay
Authors: STEPHENSON W. 
Published: July 2006

Abstract Data were obtained at 2‐month intervals for ea 31/2 years by quintuplicate sampling with an 0.1 m2 Smith‐Mclntyre grab at six selected sites in Moreton Bay. A total of 312 species‐in‐sites was obtained; when considering species‐in‐all‐sites this was reduced to 158. Both sets of data were analysed with and without data (species) reduction.After trials of several analytical methods single cyclical regressions involving Fourier transforms were selected as the main method. By prescribing a range of wavelengths, those giving the best and most significant fit to the data were obtained. Two ranges of wavelengths were used, near‐annual and long‐term. The former showed a wide range of optimal periodicities from ca 38 to 60 weeks for one set of data and ca 38 to ca 65 weeks for the other. Species with the more rapid cycles are believed to be under particularly severe control by predator/disturbers.‘Imposing’ a 52‐week cycle on the data and determining the estimated times of attainment of the first maximum shows a modal distribution with most species attaining maximum populations in September. This agrees with previous, but less intensive work, in Moreton Bay.More species show significant long‐term cycles than show annual cycles, with a spectrum of cycles of from 2 to 7 years (the range scanned), with concentrations at 3, 5 and 6 years. It is impossible to ‘explain’ these varying cycles by any conceivable combination of abiotic factors. Considering cycles of 5, 6 and 7 years, there is convincing evidence in each case that an earlier group of species is replaced, in a synchronous fashion, by a later group. Quite often species disappear from one site and are synchronously replaced at another.It was suspected that the overall situation would be complex, and although this complexity has been partially partitioned and partly clarified, much remains unexplained.
Throughfall and stemflow on silverleaf ironbark (Eucalyptus melanophloia) trees
Authors: PREBBLE R. E. , STIRK G. B. 
Published: July 2006

AbstractThe redistribution of rainfall on silverleaf ironbark (Eucalyptus melanophloia) trees in a semiarid environment at Narayen Research Station has been studied using detailed measurements on four trees.Interception accounts for about 11% of the annual rainfall with only 0.6% as stem flow; canopy storage capacity is estimated to be 2 mm and an estimate of the rain required to initiate stem flow is 7 mm.With the exception of nitrogen, the amounts of major elements returned to the soil surface beneath the tree canopy via through fall and stem flow is of the same order as that added by litter fall.