bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Expression for Spectral Line Intensity Data
Authors: Thelin Bo 
Published: June 2005

In this paper a new spectral line intensity expression for describing spectral data is shown. Linear graphs were obtained during a study of the logarithm of the following spectral line intensity proportionality: [Formula: see text] where hv is the photon energy. These results were obtained from the UV to the IR spectral regions, with the use of standard tables of spectral line intensitites from dc arc experiments. Similar relationships were obtained when an inductively coupled plasma (ICP) was used in combination with a photon-counting IDES system. Support for the exp( hv/kT) term in this expression is given by comparison with another method where spectral line intensity ratio fluctuations are studied with an ICP-IDES system. A linear graph was obtained when spectral line intensity ratio fluctuations were plotted against the differences in photon energies for the spectral transitions. Consequently, two independent methods give support to this expression over a wide spectral range with different kinds of experiments.
Evidence for a common regulation in the activation of a polyphenol oxidase by trypsin and sodium dodecyl sulfate
Authors: Gandía-Herrero Fernando , Jiménez-Atiénzar Mercedes , Cabanes Juana , García-Carmona Francisco , Escribano Josefa 
Published: June 2005

AbstractPolyphenol oxidase (PPO) was extracted from beet root, in both soluble and membrane fractions, and in both cases the enzyme was in a latent state. PPO from the membrane fraction showed no diphenolase activity unless it was activated by trypsin or sodium dodecyl sulfate (SDS). The kinetics of the activation process of latent PPO by trypsin was studied and the specific rate constant of active PPO formation,k3, showed a value of 0.03 s−1. The protease-activated form showed a pH optimum (6.5) and kinetic properties identical to those of the SDS-activated enzyme. Evidence is provided for the existence of a common peptide responsible for the regulation of the activity of the enzyme by both proteolysis and SDS detergent. Formation of the active proteolyzate was followed by spectroscopic measurements, Western blotting and partially denaturing SDS-PAGE.
Spectrophotometric determination of urinary iodine by the Sandell-Kolthoff reaction subsequent to dry alkaline ashing. Results from the Czech Republic in the period 1994–2002
Authors: Bílek Radovan , Bednář Jiří , Zamrazil Václav 
Published: June 2005

AbstractThe Czech Republic is an iodine-deficient area. Insufficient iodine intake was reduced by enriching cooking salt with iodine in the range 20–34mgI/kg. An important indicator for tracking changes in iodine nutrition over time is accurate information about urinary iodine concentrations in the population. In this paper we describe and characterize our method used for the determination of iodine in biological material, which is based on alkaline ashing of urine specimens preceding Sandell-Kolthoff reaction using brucine as a colorimetric marker. The losses of radioiodine added during sample preparation have not exceeded 0.001%. The detection limit is 2.6μgI/L and the limit of quantification is 11.7μgI/L, with intra-assay precision of 4% and inter-assay precision of 4.9%. During the period 1994–2002, the urinary iodine concentration was determined in 29,612 samples in the Institute of Endocrinology. The mean basal urinary iodine concentrations±SD were 115±69μgI/L. Of the samples, 0.7% were in severe (<20μgI/L), 9.6% in moderate (20–49μgI/L), 40.1% in mild (50–99μgI/L), 35.6% in adequate (100–200μgI/L), and 14.0% in more than adequate (>200μgI/L) subsets of iodine nutrition. A statistically significant (p<0.00001) difference was found between mean male (127μgI/L) and female (112μgI/L) urinary iodine, and an inversely proportional trend also exists in the age-related data.
Comparison of iodine contents in gastric cancer and surrounding normal tissues
Authors: Gulaboglu Mine , Yildiz Leyla , Celebi Fehmi , Gul Mustafa , Peker Kemal 
Published: June 2005

AbstractIt has been suggested that iodine plays an important role in gastric cancer. Gastric cancer ranks first among the cancers in the north-eastern Anatolia region, Turkey, where iodine deficiency is common. In this study, iodine levels were determined in gastric cancer and surrounding normal tissues in 19 patients with gastric cancer. Tissue iodine levels were determined by the Foss method based on the Sandell-Kolt-hoff reaction. Tissue iodine levels were lower in gastric cancer tissue (17.8±3.4ngI/mg protein, mean±SEM) compared with surrounding normal tissue (41.7±8.0ngI/mg protein) (p<0.001). There was positive correlation between the iodine levels in gastric cancer tissue and surrounding normal tissue (r=0.845, p<0.001). There was no significant difference in iodine levels in cancer and surrounding normal tissue between male and female subjects. The iodine deficiency in our region may be one of the factors for increased gastric cancer prevalence. Our results support the hypothesis that iodine plays an important role in gastric cancer development.
Effects of urine dilution on quantity, size and aggregation of calcium oxalate crystals induced in vitro by an oxalate load
Authors: Guerra Angela , Allegri Franca , Meschi Tiziana , Adorni Giuditta , Prati Beatrice , Nouvenne Antonio , Novarini Almerico , Maggiore Umberto , Fiaccadori Enrico , Borghi Loris 
Published: June 2005

AbstractIncreasing urinary volume is an important tool in the prevention of calcium renal stones. However, the mechanism of how it actually works is only partially understood. This study aimed at assessing how urine dilution affects urinary calcium oxalate crystallization. A total of 16 male idiopathic calcium oxalate (CaOx) stone-formers and 12 normal male subjects were studied and 4 h urine samples were taken twice, under low (undiluted urine) and high hydration conditions (diluted urine). An equal oxalate load (1.3mmol/L) was added to both types of urine and the crystallization parameters were assessed. In both stone-formers and normal subjects, the crystallization processes were significantly (p<0.05 or less) more marked in the undiluted urine than in the diluted urine in terms of: a) total quantity of calcium oxalate dihydrate (COD) and calcium oxalate monohydrate (COM) crystals; b) total quantity of crystalline aggregates; and c) aggregation index (i.e., ratio between the area occupied by crystalline aggregates and the area occupied by all the crystals present). The comparison between stone-formers and normal subjects showed that the greatest difference was for the size of COD crystals, which were larger in the urine of the stone-formers. A further important finding was an inverse relationship between changes in urinary volume and in the aggregation index (r=–0.53, p=0.004). In conclusion, urine dilution considerably reduces crystallization phenomena induced in vitro by an oxalate load in both calcium stone-formers and normal subjects.
Circulating levels of nitrated apolipoprotein A-I are increased in type 2 diabetic patients
Authors: Hermo Ricardo , Mier Cristina , Mazzotta Mary , Tsuji Masatomi , Kimura Satoshi , Gugliucci Alejandro 
Published: June 2005

AbstractRecent work has shown that high-density lipoprotein (HDL) isolated from human atherosclerotic lesions and the blood of patients with established coronary artery disease contains elevated levels of 3-nitrotyrosine and 3-chlorotyrosine. A higher nitrotyrosine content in lipoprotein is significantly associated with diminished cholesterol efflux capacity of the lipoprotein. Since accelerated atherogenesis is a key complication of diabetes mellitus, and nitrosative stress has recently been implicated in diabetic pathology, we set out to demonstrate an increase in the circulating levels of nitrated apolipoprotein A (apoA)-I in type 2 diabetic patients and its putative correlation with metabolic biomarkers. In this work we addressed this hypothesis in a case-control study with 30 type 2 diabetic patients and 30 age-matched control subjects. Nitrated apoA-I was 3280±1910 absorbance peak area/apoA-I (g/L) for diabetic patients and 2320±890 for control subjects (p<0.037). This represents a 50% increase in circulating nitrated apoA-I in diabetic patients to age-matched controls. Diabetic patients also showed increases of a similar magnitude in circulating advanced glycation endproducts measured as pentosidine fluorescence (44.16±16.26 vs. 30.84±12.86 AU; p<0.01) and in circulating lipoperoxides (46.0±18.0 vs. 37.2±18.0nmol/L; p<0.03). No significant correlation was found between nitration of apoA-I and glycosylated hemoglobin or any of the other parameters measured. If proven in subsequent functional and in vivo studies, increased nitrated apoA-I would represent another mechanism by which nitrosative stress participates in diabetic macro-angiopathy.
A simple method for estimating equilibrium constants for serum testosterone binding resulting in an optimal free testosterone index for use in elderly men
Authors: Ross H. Alec , Meuleman Eric J. , Sweep Fred C. G. J. 
Published: June 2005

AbstractAn algorithm was developed to evaluate equilibrium constants for testosterone (Te) and sex hormone-binding globulin (SHBG) or albumin from serum free testosterone (FTe) measurements performed in a panel of 30 healthy elderly men by means of a near-reference method, i.e., symmetric dialysis (affinity constants: SHBG-Te, 1.13×10
Standardized quantification of circulating peripheral tumor cells from lung and breast cancer
Authors: Pachmann Katharina , Clement Joachim H. , Schneider Claus-Peter , Willen Babette , Camara Oumar , Pachmann Ulrich , Höffken Klaus 
Published: June 2005

AbstractDetection and quantitation of circulating tumor cells from solid epithelial tumors could become a valuable tool for therapy monitoring if the procedure can be standardized. In the present work we assessed the influence of preanalytical handling, storage and white blood cell isolation on analysis of a population of spiked tumor cell-line cells and intrinsically present epithelial cells in the peripheral blood of breast and lung cancer patients and the sensitivity of their detection. Sucrose density separation did not enrich epithelial cells, and even depleted them, leading to a gross underestimation of their numbers (3/13 positive, between 2.9 and 50cells/mL) in comparison to red blood cell lysis (13/13 positive, between 77,200 and 800cells/mL). Short-term storage of whole blood samples for up to 7days had little influence on the number of epithelial cells recovered. The effectiveness of magnetic bead enrichment was dependent on the number of relevant cells and the volume used for enrichment. Red blood cell lysis and fluorochrome-labeled antibody staining in a no-wash procedure with subsequent laser scanning cytometry allowed the detection of circulating epithelial cells in 92% of breast and lung cancer patients. Two examples of how this method can be applied for the longitudinal analysis in individual patients are shown, with an increase in numbers preceding relapse and a decrease paralleling tumor reduction. The proposed simple and easy method allows close monitoring, which may help in real-time analysis of the response of solid tumors, especially their systemic component, to therapy and hopefully will contribute to more individually tailored therapy.
Radioimmunoassay for plasma C-type natriuretic peptide determination: a methodological evaluation
Authors: Del Ry Silvia , Maltinti Maristella , Emdin Michele , Passino Claudio , Catapano Giosué , Giannessi Daniela 
Published: June 2005

AbstractC-Type natriuretic peptide (CNP) is a member of the family of natriuretic peptides with vasodilatory properties, and is produced and secreted by endothelial cells. It seems to play a central role in the paracrine vasomotor control of tone and to be important in several clinical conditions characterized by endothelial dysfunction. We evaluated the analytical performance of a commercially available radioimmunoassay for CNP after a preliminary extraction with Sep-Pak C18. Its analytical reliability was checked by determination of CNP plasma levels in healthy subjects (n=23) and in patients with different diseases, likely characterized by endothelial dysfunction, such as chronic heart failure (n=133) and cirrhosis (n=84). The extraction yield was 78±3%. Accuracy of the radiommunological determination was evaluated by dilution (45–370μL of extracted plasma) and recovery tests (>80%). Between- and within-assay variabilities were ≤10% and analytical sensitivity was 0.41±0.015pg/tube. Plasma CNP in patients with chronic heart failure and with cirrhosis was significantly raised compared to controls (p<0.0001 and p=0.001, respectively). The sensitivity, accuracy and variability levels of the method proposed for CNP assay was suitable for reliable detection of changes in CNP plasma levels in the clinical setting.
Evaluation of the Konelab 20XT clinical chemistry analyzer
Authors: Stojanović Nataša , Rogić Dunja , Stavljenić-Rukavina Ana 
Published: June 2005

AbstractThe Konelab 20XT (Thermo Electron Oy, Finland) is a clinical chemistry analyzer for colorimetric, immunoturbidimetric and ion-selective electrode measurements. The aim of our work was to evaluate the analytical performances of the Konelab 20XT according to the European Clinical Chemistry Laboratory Standards Guidelines. A total of 30 analytes including substrates, enzymes, electrolytes and specific proteins were tested. Investigation results showed low imprecision (within-run coefficient of variation was below 3.5% and between-day coefficient of variation was less than 2.5% for most analytes at all three levels studied) and acceptable accuracy of the analyzer. No significant sample- or reagent-related carry-over was found. It was demonstrated that the analytical system operates within the claimed linearity ranges. The results compared well with those obtained by instruments routinely used in our laboratory (Olympus AU2700, Behring Nephelometer II). In general, the data on interference by hemoglobin, hyperbilirubinemia and turbidity are in accordance with known facts. However, slight hemolysis was found to interfere with the alkaline phosphatase (ALP) assay and mild lipemia affected the glucose assay. The Konelab 20XT is an easy-to-use analyzer that is suitable for routine and emergency analyses in small laboratories.
Hydrophobisation and densification of wood by different chemical treatments
Authors: Bach Sylvie , Belgacem Mohamed Naceur , Gandini Alessandro 
Published: June 2005

Abstract
Samples of Pinus sylvestris were treated with different reagents bearing isocyanate, carboxylic anhydride or oxirane functions to induce reaction with the OH groups of the various components of wood. Conditions were optimised to achieve maximum grafting. When the reagents also carried a polymerisable function, a monomer (styrene or methyl methacrylate) was incorporated into the wood morphology after the derivatisation reaction. Subsequent radical polymerisation produced chemical incorporation of some of the resulting macromolecules. The properties of the doubly modified samples were assessed using a wide variety of tests. Both the hydrophobic character and the density increased considerably, suggesting improved lifetime and extended domains of application.
Functionalisation of wood by reaction with 3-isocyanatopropyltriethoxysilane: Grafting and hydrolysis of the triethoxysilane end groups
Authors: Tingaut Philippe , Weigenand Oliver , Militz Holger , Jéso Bernard De , Sèbe Gilles 
Published: June 2005

Abstract
The chemical modification of maritime pine sapwood (Pinus pinaster Soland) with 3-isocyanatopropyltriethoxysilane (IPTES) and its subsequent hydrolysis were investigated. The formation of urethane linkages after the carbamoylation reaction was confirmed by Fourier-transform infrared (FTIR) spectroscopy. The weight percent gain (WPG) obtained was found to be commensurate with the quantity of IPTES in the reagent solution. Swelling measurements combined with scanning electron microscopy-energy dispersive X-ray (SEM-EDX) analysis showed that the reaction occurred within the wood cell walls. Hydrolysis of the grafted triethoxysilane ends in highly carbamoylated wood was also envisaged: the modifications generated after prolonged contact with water were studied by FTIR spectroscopy and 13C and 29Si nuclear magnetic resonance cross-polarisation with magic-angle spinning (NMR CP MAS) analysis. The chemical environments found for silicon (Si–OH, Si–OEt or Si–OSi) before and after hydrolysis were thus identified and a schematic representation of the silicon structures most often encountered in modified wood was proposed.
Bioactive phenolic substances in industrially important tree species. Part 4: Identification of two new 7-hydroxy divanillyl butyrolactol lignans in some spruce, fir, and pine species
Authors: Willför Stefan , Eklund Patrik , Sjöholm Rainer , Reunanen Markku , Sillanpää Reijo , Schoultz Sebastian von , Hemming Jarl , Nisula Linda , Holmbom Bjarne 
Published: June 2005

Abstract
A few lignans, that is, 7-hydroxymatairesinol, secoisolariciresinol, lariciresinol, and nortrachelogenin, predominate in a large proportion of the industrially important softwood species used. Some other lignans, of which some still are unidentified, are also present in lower amounts. Softwood knots, i.e., the branch bases inside tree stems, commonly contain exceptionally large amounts of free aglycone lignans, which has provided a great opportunity to isolate sufficient amounts of softwood lignans for structural characterisation. Here we present the identification and characterisation of two new 9-epimers of 7-hydroxy divanillyl butyrolactol lignans, (7S,8R,8′R,9′R)-4,4′,7-trihydroxy-3,3′-dimethoxylignano-9′,9′-lactol and (7S,8R,8′R,9′S)-4,4′,7-trihydroxy-3,3′-dimethoxylignano-9′,9′-lactol, in knotwood of Colorado spruce (Picea pungens), from tentative GC-MS analysis to final determination of the structure by NMR spectroscopy and X-ray analysis. Further analyses have verified the occurrence of these lignans, which were earlier incorrectly addressed by our group as isomers of liovil, in several spruce, pine, and fir species.
Characterization of physiological functions of sapwood IV: Formation and accumulation of lignans in sapwood of Cryptomeria japonica (L.f.) D. Don after felling
Authors: Imai Takanori , Sato Mika , Takaku Naohiro , Kawai Shingo , Ohashi Hideo , Nomura Masaki , Kushi Masayoshi 
Published: June 2005

AbstractMatairesinol and pinoresinol were isolated from sugisapwood 40 days after felling. These lignans were not detected in the heartwood. Accordingly, they are probably the result of post-mortem biosynthesis in sapwood parenchyma cells.
An assessment of the feasibility of ultrasound as a defect detector in lumber
Authors: Dyk Herman van , Rice Robert W. 
Published: June 2005

Abstract
This study investigated the limitations of certain attributes for use in detecting internal defects using ultrasonic methods in spruce dimension lumber. Wave propagation in the radial direction and the effect of induced defects on ultrasonic wave characteristics were examined. Ultrasonic velocity, a parameter often applied, was found to be ineffective due to changes in wavelength and frequency when large defects were present. Amplitude, peak frequency magnitude and the area under the frequency spectra showed statistically significant differences between clear and defect-bearing samples, but among-sample variation was found to be too high because of localized density differences and microstructure, so that these methods were not consistently reliable. When sound intensity level was calculated, the variation among samples decreased and distinctions could be made between clear and defect-bearing wood, both within and among the samples tested. Certain attributes of the frequency spectra also showed clear changes with the introduction of defects.
Vibrational properties of green wood in high-temperature water vapor
Authors: Kubojima Yoshitaka , Suzuki Youki , Tonosaki Mario 
Published: June 2005

Abstract
The object of this study was to measure basic wood properties when water in wood is lost by heating under high temperature and high humidity. Using Sitka spruce (Picea sitchensis Carr.) specimens with dimensions of 110 mm (R)×25 mm (L)×8 mm (T), temperature and weight were measured and free-free flexural vibration tests were conducted in water vapor at 115–150°C and 75–98% relative humidity. The results were compared to those at high temperatures without humidity control under atmospheric pressure. Early in the drying process, the resonance frequency and loss tangent showed a minimum and maximum, respectively. Temporal changes in the temperature, moisture content and vibrational properties were similar to those in heating without humidity control, while the specific Young's modulus and loss tangent during the drying processes were much smaller and greater, respectively, than those in heating without humidity control. Hence, we concluded that the wood was remarkably softened by high temperature and moisture.
The stiffness modulus in Norway spruce as a function of year ring
Authors: Koponen Tiina , Karppinen Timo , Hæggström Edward , Saranpää Pekka , Serimaa Ritva 
Published: June 2005

AbstractThe elastic properties of Norway spruce were studied by means of ultrasound. Samples were from stems that were grown either at a medium- or a high-fertility site in Finland. The stiffness modulus was determined in the longitudinal, radial, and tangential directions as a function of the distance from the pith using 1-mm-thick samples. Tangentially cut samples contained only earlywood, while radially and longitudinally cut samples contained both earlywood and latewood. The stiffness modulus in the longitudinal direction for Norway spruce grown at a medium-fertility site increased with distance from the pith from 6±1 to 8.5±1 GPa. This parameter increased as the mean microfibril angle decreased. In the radial and tangential directions, the stiffness modulus was nearly constant, at 1±0.15 and 0.35±0.04 GPa, respectively. The longitudinal stiffness modulus of fast-growing clonal trees, which contained a large share of juvenile wood and were growing on a fertile site, was ca. 30% smaller (4±1 GPa near the pith and 6±1 GPa at the age of 12 years) than that of trees on a medium-fertility site. No difference was found in the radial and tangential stiffness modulus between stems grown at the two sites.
Effect of climatic variables on chromated copper arsenate (CCA) leaching during above-ground exposure
Authors: Taylor James L. , Cooper Paul A. 
Published: June 2005

Abstract
Until recently, most research on the leaching of preservatives from treated wood was conducted in the laboratory. Although these studies have contributed to the understanding of leaching, the data generated under controlled conditions often do not apply to leaching during natural exposure and weathering. In addition, little is known about the effects of climatic variables and long-term emission rates. This paper examines leaching of chromated copper arsenate (CCA) from lumber exposed above ground to 685 mm of precipitationduring 351 days of natural weathering. Stepwise multiple regression analysis revealed relationships between leaching and a number of treatment and climatic variables, including: species of wood, initial preservative loading, amount of precipitation, average air temperature, average light intensity, pH and duration of rain event. Regression models explained approximately 30% of the variation in chromium and arsenic leaching and 44% of the variation in copper leaching.