bluuebunny/crossref_metadata_2025_split huggingface dataset:
Replitase: Complete machinery for DNA synthesis
Authors: Murthy Shalini , Reddy G. Prem‐Veer 
Published: September 2006

AbstractReplication of nuclear DNA in eukaryotes presents a tremendous challenge, not only due to the size and complexity of the genome, but also because of the time constraint imposed by a limited duration of S phase during which the entire genome has to be duplicated accurately and only once per cell division cycle. A challenge of this magnitude can only be met by the close coupling of DNA precursor synthesis to replication. Prokaryotic systems provide evidence for multienzyme and multiprotein complexes involved in DNA precursor synthesis and DNA replication. In addition, fractionation of nuclear proteins from proliferating mammalian cells shows co‐sedimentation of enzymes involved in DNA replication with those required for synthesis of deoxynucleoside triphosphates (dNTPs). Such complexes can be isolated only from cells that are in S phase, but not from cells in G0/G1 phases of cell cycle. The kinetics of deoxynucleotide metabolism supporting DNA replication in intact and permeabilized cells reveals close coupling and allosteric interaction between the enzymes of dNTP synthesis and DNA replication. These interactions contribute to channeling and compartmentation of deoxynucleotides in the microvicinity of DNA replication. A multienzyme and multiprotein megacomplex with these unique properties is called “replitase.” In this article, we summarize some of the relevant evidence to date that supports the concept of replitase in mammalian cells, which originated from the observations in Dr. Pardee's laboratory. In addition, we show that androgen receptor (AR), which plays a critical role in proliferation and viability of prostate cancer cells, is associated with replitase, and that identification of constituents of replitase in androgen‐dependent versus androgen‐independent prostate cancer cells may provide insights into androgen‐regulated events that control proliferation of prostate cancer cells and potentially offer an effective strategy for the treatment of prostate cancer. J. Cell. Physiol. 209: 711–717, 2006. © 2006 Wiley‐Liss, Inc.
Radiosynthesis of 6‐([18F]fluoroacetamido)‐1‐hexanoicanilide ([18F]FAHA) for PET imaging of histone deacetylase (HDAC)
Authors: Mukhopadhyay Uday , Tong William P. , Gelovani Juri G. , Alauddin Mian M. 
Published: September 2006

AbstractRadiosynthesis of a novel substrate for histone deacetylase (HDAC), 6‐([18F]fluoroacetamido)‐1‐hexanoicanilide ([18F]FAHA, [18F]‐3) is reported. For precursor synthesis, compound 1 (6‐amino‐1‐hexanoicanilide) was prepared by the reaction of 6‐amino hexanoic acid with thionyl chloride in dichloroethane followed by addition of aniline. Compound 1 was reacted with bromoacetic anhydride in tetrahydrofuran (THF) in the presence of triethylamine to produce the precursor compound 6‐(bromoacetamido)‐1‐hexanoicanilide 2. Fluorination reactions were performed using tetrabutylammonium fluoride in various solvents at 80°C to prepare the unlabeled reference compound 3. Radiofluorinations were performed using either n‐Bu4N18F or K18F/kryptofix, and the crude product was purified by high performance liquid chromatography (HPLC). The radiochemical yields were 9–13% decay corrected (d.c.) with an average of 11% using K18F/kryptofix, and specific activity >2 GBq/µmol at the end of synthesis. The synthesis time was 67–75 min from the end of bombardment (EOB). Copyright © 2006 John Wiley & Sons, Ltd.
Lagged relationships between North American snow mass and atmospheric teleconnection indices
Authors: Sobolowski Stefan , Frei Allan 
Published: September 2006

AbstractRelationships between North American winter (January, February, March or JFM) snow mass, or snow water equivalent (SWE), between 1980 and 1997, and four teleconnection indices are explored at different spatial and temporal scales, with teleconnection indices leading SWE by one to two seasons. Summer (July, August, September, or JAS) and fall (October, November, December, or OND) Pacific North American pattern (PNA), North Atlantic Oscillation (NAO), El‐Nino Southern Oscillation (ENSO), and the Pacific Decadal Oscillation (PDO) are included in this analysis. Principal components analysis of the SWE data set results in four components, explaining over 56% of the variance in the SWE signal which have significant relationships to ENSO, PDO, and NAO. Strong spatial components associated with these relationships emerge, with the first component (NAO, ENSO) located in the northcentral to northwestern regions of the United States and the southcentral to southwestern regions of Canada. A third component (PDO) stretches from the midwest to the east coast of the United States, New England, and the Atlantic Provinces. Ranked correlation analyses using the SWE data set, and additional analyses of station observations in order to extend the time domain, corroborate and elucidate the PCA results. Examinations of these relationships at different spatial scales, and over varying time domains, indicate that there may be some scale‐dependant predictive ability for North American snow mass. Copyright © 2006 Royal Meteorological Society.
Analysis and objective mapping of extreme daily rainfall in Catalonia
Authors: Carmen Casas M. , Herrero Mònica , Ninyerola Miquel , Pons Xavier , Rodríguez Raül , Rius Anna , Redaño Angel 
Published: September 2006

AbstractThe main objective of this study is to determine the maximum daily precipitation in Catalonia for several established return periods with a high spatial resolution. For this purpose, the maximum daily rainfall annual series from 145 pluviometric stations of the Instituto Nacional de Meteorología (INM) (Spanish Weather Service) in Catalonia have been analyzed. Using the L‐moments method of Hosking, every series has been fitted by the extreme value distribution function of Gumbel. From this fitting, the maximum daily precipitation for each of the pluviometric stations corresponding to return periods between 2 and 500 years, have been determined. Applying the Cressman method, the spatial analysis of these values has been achieved. Monthly precipitation climatological data, obtained from the application of Geographic Information Systems (GIS) techniques, have been used as the initial field for the analysis. The maximum daily precipitation at 1 km2spatial resolution on Catalonia has been objectively determined by the method employed, and structures with wavelength longer than approximately 35 km can be identified. The results show that places where the maximum daily precipitation values are expected are the zone of Guilleries in the Transversal Range, in the highest zones of the Catalan Pyrenees and Cape Creus zone at the northeastern end of Catalonia and in the south, around the Prelittoral Mountain Range between the Mountains of Prades and Montsià. A good fit between the distribution of minimum values and the driest Catalan areas has been found, the lowest values being on the western end of the Central Basin. Copyright © 2006 Royal Meteorological Society.
Trends in extreme daily precipitation and temperature near lake Hövsgöl, Mongolia
Authors: Nandintsetseg Banzragch , Greene J. Scott , Goulden Clyde E. 
Published: September 2006

AbstractA long‐term (1963–2002) set of daily maximum and minimum temperature and precipitation data are analyzed for the Hövsgöl Basin area, Mongolia. Six indices of extreme temperature and eight indices of extreme precipitation are examined. Results suggest that climate conditions over northern Mongolia are changing as indicated by a warming trend identified during the study period. Significant increases are detected in the annual number of hot days and warm nights in this region. Associated with these changes are concomitant decreases in the annual number of cold days and cold nights. The number of days with precipitation has increased slightly while the annual total precipitation has not significantly increased in northern Mongolia. On an average, there was no significant decrease in the maximum number of consecutive dry days or increase in the wet days. The 5‐day precipitation total showed a small increase. Copyright © 2006 Royal Meteorological Society.
An Arctic and antarctic perspective on recent climate change
Authors: Turner John , Overland James E. , Walsh John E. 
Published: September 2006

AbstractWe contrast recent climatic and environmental changes and their causes in the Arctic and the Antarctic. There are continuing increases in surface temperatures, losses of sea ice and tundra, and warming of permafrost over broad areas of the Arctic, while most of the major increase in Antarctic temperatures is on the Antarctic Peninsula associated with sea ice loss in the Bellingshausen–Amundsen Seas sector. While both natural atmospheric and oceanic variability, and changes in external forcing including increased greenhouse gas concentrations, must be considered in the quest for understanding such changes, the interactions and feedbacks between system components are particularly strong at high latitudes. For the 1950s to date in the Arctic and for 1957 to date in the Antarctic, positive trends in large‐scale atmospheric circulation represented by the Arctic oscillation (AO) and Antarctic oscillations (AAO) and the Pacific North American (PNA) pattern contribute to the long‐term temperature trends. However, continuing Arctic trends during the last decade of near neutral AO will require alternate explanations. The trend in the AAO since 1950 is larger than expected from natural variability and may be associated with the decrease in stratospheric ozone over Antarctic. The persistence shown in many Arctic and Antarctic Peninsula components of climate and their influence through possible feedback supports continuation of current trends over the next decade. One can expect large spatial and temporal differences, however, from the relative contributions of intrinsic variability, external forcing, and internal feedback/amplifications. It is particularly important to resolve regional feedback processes in future projections based on modeling scenarios. Copyright © 2006 Royal Meteorological Society.
Frequency and within‐type variations of large‐scale circulation types and their effects on low‐frequency climate variability in central europe since 1780
Authors: Beck C. , Jacobeit J. , Jones P. D. 
Published: September 2006

AbstractThis study investigates the importance of large‐scale atmospheric circulation changes for Central European climate variations during the last two centuries. On the basis of an objective classification of monthly mean sea level pressure (SLP) grids reconstructed back to 1780 and monthly historical station data for the same period, temperature and precipitation changes in Central Europe since 1780 are decomposed into two parts; one part due to frequency changes of large‐scale circulation types, and the other part caused by (dynamic and climatic) changes within these circulation types. This is achieved by applying a particular decomposition scheme for moving 31‐year time windows during the 1780–1995 period. Results indicate that large parts of the long‐term variations in Central European climate cannot be explained sufficiently by frequency changes of circulation types. Roughly one half of these variations—even up to 80% during July—can be ascribed to varying internal properties of some major circulation types. Percentages of frequency‐related and within‐type‐related climate changes are seen to vary on decadal to multidecadal time scales, thus implying that relationships between large‐scale circulation patterns and regional climates are characterised by distinct instationarities. Furthermore, regional climate variations, being attributable to within‐type changes of major circulation types, can only partly be explained by corresponding variations in dynamic properties (vorticity, intensity) of these circulation types. This points to the importance of further sources for within‐type variability, including subgrid‐scale processes, synoptic‐scale variations, and modifications of the climatic boundary conditions. Copyright © 2006 Royal Meteorological Society.
Relations of South American summer rainfall interannual variations with the Pacific Decadal Oscillation
Authors: Kayano Mary T. , Andreoli Rita V. 
Published: September 2006

AbstractThe anomaly patterns of rainfall in South America for El Niño/Southern Oscillation (ENSO) extreme conditions stratified according to the high, low, and normal Pacific (inter‐) Decadal Oscillation (PDO) phases (HPDO, LPDO and NPDO) are examined for the three bi‐months of the season from November to April. El Niño (EN) and La Niña (LN) composites as well as the linear (EN − LN) and nonlinear (EN + LN) components of the precipitation anomaly patterns relative to ENSO show substantial differences among the three PDO phases. The differences in the strength of ENSO teleconnections for the South American rainfall might be related to the PDO, which creates a background for these teleconnections acting constructively (destructively) when ENSO and PDO are in the same (opposite) phase. An interesting aspect is the occurrence of robust structures of the nonlinear component, which are due to the same sign rainfall anomalies for EN and LN composites. This is particularly conspicuous for the HPDO over eastern Brazil in the South Atlantic Convergence Zone (SACZ) region during Nov/Dec and Jan/Feb, for the HPDO over northern/northwestern South America during Mar/Apr, and for the NPDO over northeastern Brazil during Mar/Apr. The results presented here might have relevant implications for climate monitoring purposes. Copyright © 2006 Royal Meteorological Society
Covariabilities of spring soil moisture and summertime United States precipitation in a climate simulation
Authors: Wu Wanru , Dickinson Robert E. , Wang Hui , Liu Yongqiang , Shaikh Muhammad 
Published: September 2006

AbstractThis paper explores the space‐time connections between springtime soil moisture and summer precipitation over the continental United States by applying a singular value decomposition (SVD) method to a 50‐year climate simulation. The first two SVD modes were analyzed. The two leading SVD modes account for 43% of the squared covariance between spring soil moisture and summer precipitation. Their corresponding components explain 14% of the soil moisture variance and 19% of the precipitation variance, respectively, which is larger than that contributed by tropical Pacific sea‐surface temperatures (SSTs). The temporal correlations between the two expansion coefficients of each SVD mode are 0.83 and 0.88, respectively, indicating a significant association between spring soil moisture variation and summer precipitation variability. Both positive and negative cross‐correlations exist over different regions of the United States in the two modes. Linear regression relates surface relative humidity and surface air temperature to the soil moisture SVD time series. The patterns revealed by the SVD analysis show where the local soil moisture‐precipitation coupling contributes to the model's simulation of precipitation. Copyright © 2006 Royal Meteorological Society
Climatic effects of urbanization in istanbul: a statistical and modeling analysis
Authors: Ezber Yasemin , Lutfi Sen Omer , Kindap Tayfun , Karaca Mehmet 
Published: September 2006

AbstractStatistical and numerical modeling tools were used to investigate the climatic effects of urbanization in Istanbul, the largest city in Turkey. Mann–Kendall trend test was applied to minimum temperature data from stations located in urban, suburban and rural areas in Istanbul to determine the existence and significance of trends, and the approximate years in which changes in the trends started. In addition, using a mesoscale atmospheric model, a sensitivity experiment was carried out to explore the atmospheric effects of urbanization in the city. Both statistical and modeling analyses indicated significant warming in the atmosphere over the urbanized areas. Mann–Kendall tests indicated statistically significant positive trends in the time series of the differences in minimum temperatures between urban and rural stations. Seasonal analyses showed that the urbanization effect on climate was most pronounced in summer. In most cases, the changes in the trends occurred in the 1970s and 1980s when the population growth rate in Istanbul increased dramatically. The model results exhibited a significant expansion of the urban heat island in Istanbul from 1951 to 2004, fairly consistent with the expansion of the city in this period. A two‐cell structure for the urban heat island emerged at the reference level from the difference of the July simulations with current and past landscapes: one on the European side and the other on the Asian side of the city. The maximum reference‐level temperature difference between the past and present simulations was found to be around 1 °C. The modeling experiment also indicated that the velocity of the prevailing northeasterly wind and the water vapor mixing ratio were both reduced over the city. The heating effect due to urbanization was found to penetrate about 600–800 m height in the atmosphere over the city, and the two surface heat island cells were found to combine aloft. Copyright © 2006 Royal Meteorological Society
Mobilization of endothelial precursor cells: Systemic vascular response to musculoskeletal trauma
Authors: Laing A.J. , Dillon J.P. , Condon E.T. , Street J.T. , Wang J.H. , McGuinness A.J. , Redmond H.P. 
Published: September 2006

AbstractPostnatal vasculogenesis, the process by which vascular committed bone marrow stem cells or endothelial precursor cells (EPC) migrate, differentiate, and incorporate into the nacent endothelium contributing to physiological and pathological neovascularization, has stimulated much interest. Its contribution to tumor nonvascularization, wound healing, and revascularization associated with skeletal and cardiac muscles ischaemia is established. We evaluated the mobilization of EPCs in response to musculoskeletal trauma. Blood from patients (n = 15) following AO type 42a1 closed diaphyseal tibial fractures was analyzed for CD34 and AC133 cell surface marker expression. Immunomagnetically enriched CD34+ mononuclear cell (MNCCD34+) populations were cultured and examined for phenotypic and functional vascular endothelial differentiation. Circulating MNCCD34+ levels increased sevenfold by day 3 postinjury. Circulating MNCAC133+ increased 2.5‐fold. Enriched MNCCD34+ populations from day 3 samples in culture exhibited cell cluster formation with sprouting spindles. These cells bound UEA‐1 and incorporated fluorescent DiI‐Ac‐LDL intracellularily. Our findings suggest a systemic provascular response is initiated in response to musculoskeletal trauma. Its therapeutic manipulation may have implications for the potential enhancement of fracture healing. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:44–50, 2007
Biofilm formation by bacteria isolated from retrieved failed prosthetic hip implants in an in vitro model of hip arthroplasty antibiotic prophylaxis
Authors: Tunney M.M. , Dunne N. , Einarsson G. , McDowell A. , Kerr A. , Patrick S. 
Published: September 2006

AbstractBacterial infection primarily with Staphylococcus spp. and Propionibacterium acnes remains a significant complication following total hip replacement. In this in vitro study, we investigated the efficacy of gentamicin loading of bone cement and pre‐ and postoperative administration of cefuroxime in the prevention of biofilm formation by clinical isolates. High and low initial inocula, representative of the number of bacteria that may be present at the operative site as a result of overt infection and skin contamination, respectively, were used. When a high initial inoculum was used, gentamicin loading of the cement did not prevent biofilm formation by the 10 Staphylococcus spp. and the 10 P. acnes isolates tested. Similarly, the use of cefuroxime in the fluid phase with gentamicin‐loaded cement did not prevent biofilm formation by four Staphylococcus spp. and four P. acnes isolates tested. However, when a low bacterial inoculum was used, a combination of both gentamicin‐loaded cement and cefuroxime prevented biofilm formation by these eight isolates. Our results indicate that this antibiotic combination may protect against infection after intra‐operative challenge with bacteria present in low numbers as a result of contamination from the skin but would not protect against bacteria present in high numbers as a result of overt infection of an existing implant. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:2–10, 2007
Radical scavenging properties of protein hydrolysates from Jumbo flying squid (Dosidicus eschrichitii Steenstrup) skin gelatin
Authors: Lin Lin , Li Ba‐fang 
Published: September 2006

AbstractGelatin extracted from Jumbo flying squid skin was hydrolyzed with serials of protease. The scavenging effects of gelatin hydrolysates on superoxide and hydroxyl radical were assessed by chemiluminescence analysis. Properase E and pepsin have shown efficient hydrolysis of squid skin gelatin to obtain high radical scavenging activity peptides. The conditions chosen for enzymic hydrolysis of squid skin gelatin with properase E were pH 9.0, 45 °C, 3 h reaction time, and enzyme‐to‐substrate ratio of 1:50. Hydrolysates combining properase E and pepsin showed the best radical scavenging activity. For fragmented hydrolysates by ultrafiltration, fractions UF‐2 (Mw < 2000 Da) had high yield and radical scavenging activity. Copyright © 2006 Society of Chemical Industry
Bioavailability of calcium, magnesium and phosphorus in rats fed probiotic, prebiotic and synbiotic powder follow‐up infant formulas and their effect on physiological and nutritional parameters
Authors: Pérez‐Conesa Darío , López Ginés , Abellán Pedro , Ros Gaspar 
Published: September 2006

AbstractThe effect of infant formulas supplemented with functional ingredients on calcium (Ca), magnesium (Mg) and phosphorus (P) bioavailability was investigated in rats. Seven follow‐up infant formulas containing probiotics (Bifidobacterium bifidum and Bifidobacterium longum), prebiotics (galactooligosaccharides at 12, 50 and 100 g kg−1) or synbiotics (bifidobacteria and galactooligosacccharides) were administered to weanling rats for 30 days. A 3 day mineral balance was performed over three periods (8–10, 18–20 and 28–30 days) to monitor mineral apparent absorption and retention ratios and physiological and nutritional parameters. Feeding rats on infant formula‐based diets showed high feed efficiency (≥0.46). It was found that infant formulas supplemented with probiotics and/or prebiotics for 30 days increased Ca, Mg and P bioavailability in rats. Mineral apparent absorption and retention ratios were higher than 90% for Ca and P and 80% for Mg during the first balance period regardless of the infant formula used, but they decreased during the next two balance periods. Although it was not possible to select one infant formula as the best to improve mineral absorption, the 100 g kg−1 prebiotic and 50 and 100 g kg−1 synbiotic infant formulas were the most efficient at increasing Ca, Mg and P bioavailability compared with the control group. Copyright © 2006 Society of Chemical Industry