bluuebunny/crossref_metadata_2025_split huggingface dataset:
How a low tissue O2 strategy could be conserved in early crustaceans: the example of the podocopid ostracods
Authors: Corbari Laure , Carbonel Pierre , Massabuau Jean-Charles 
Published: November 2004

SUMMARYAn adaptation strategy whereby O2 partial pressure, PO2, in the tissues is maintained within a low,narrow range of 1–3 kPa, largely independent of the inspired PO2, has been reported in water- and air-breathing poikilotherms and in homeotherms. Based on the postulate that this basic cellular mechanism has been established since the early stages of evolution, it has been hypothesized that it could be the consequence of an early adaptation strategy to maintain cellular oxygenation within the same low and primitive range. To test this hypothesis we studied the basic mechanisms of oxygen regulation in podocopid ostracods, minute crustaceans that have existed on earth for at least 500 million years. Podocopids lack any regulatory mechanism for adapting their ventilation to cope with changes in water oxygenation, and instead adjust their tissue oxygenation status by migrating through the O2 gradient to sediment layers where the PO2 of the water is 3–5 kPa. Experimental manipulation of the O2 profile induced their vertical migration to follow this precise water PO2 and demonstrates the existence of a regulation strategy. This strategy must be associated with the lower PO2 values within the animal's carapace valves, showing that podocopids can actively regulate their tissue PO2 at constant but even lower values than the water. In conclusion, the low tissue PO2strategy could have existed in early crustaceans and, by extension, in early animals.
Metamorphosis inXenopus laevisis not associated with large-scale nuclear DNA content variation
Authors: Freeman Jennifer L. , Rayburn A. Lane 
Published: November 2004

SUMMARYAmphibian metamorphosis is a complex process that has been speculated to involve DNA amplification and chromatin rearrangement. While recent studies have concentrated on chromatin rearrangement, only a few studies have dealt with variation in the amount of DNA during amphibian metamorphosis. In this study, nuclei were isolated from Xenopus laevis at various developmental stages. The nuclei were examined in both an unfixed state and a fixed state. The nuclei were stained with propidium iodide and analyzed by flow cytometry to determine their fluorescence intensity. The unfixed nuclei had higher fluorescence variation compared with the fixed nuclei. This increase in variation appeared due to the presence of nuclei of variable fluorescence intensity within the unfixed nuclei. Upon optimum fixation, which has been speculated to result in more homogeneous chromatin conformation and to reduce staining artifacts, the nuclei were observed to have less fluorescence intensity variation. The differential fluorescence observed in this study is consistent with the hypothesis that large-scale intra-individual DNA variation is not associated with amphibian metamorphosis.
Prognostic Value of an Early Soluble L-Selectin (sCD62L) Assay for Risk Assessment in Blunt Multiple Trauma: A Metaanalysis
Authors: Stengel Dirk , Bauwens Kai , Keh Didier , Gerlach Herwig , Ekkernkamp Axel , Tauber Rudolf , Kerner Thoralf 
Published: November 2004

AbstractBackground: After severe trauma, decreased plasma concentrations of the soluble adhesion molecule L-selectin (sCD62L) have been linked to an increased incidence of lung failure and multiorgan dysfunction syndrome (MODS). Individual studies have had conflicting results, however. We examined multiple studies in an attempt to determine whether early sCD62L concentrations are predictive of major complications after severe trauma.Methods: We performed a systematic review of six electronic databases and a manual search for clinical studies comparing outcomes of multiply injured patients (Injury Severity Score ≥16) depending on their early sCD62L blood concentrations. Because of various outcome definitions, acute lung injury (ALI) and adult respiratory distress syndrome (ARDS) were studied as a composite endpoint. Weighted mean differences (WMDs) in sCD62L concentrations were calculated between individuals with and without complications by fixed- and random-effects models.Results: Altogether, 3370 citations were identified. Seven prospective studies including 350 patients were eligible for data synthesis. Published data showed the discriminatory features of sCD62L but did not allow for calculation of measures of test accuracy. Three of four studies showed lower early sCD62L concentrations among individuals progressing to ALI and ARDS (WMD = −229 μg/L; 95% confidence interval, −476 to 18 μg/L). No differences in sCD62L concentrations were noted among patients with or without later MODS. Nonsurvivors had significantly lower early sCD62L plasma concentrations (WMD = 121 μg/L; 95% confidence interval, 63–179 μg/L), but little information was available on potential confounders in this group.Conclusions: Early decreased soluble L-selectin concentrations after multiple trauma may signal an increased likelihood of lung injury and ARDS. The findings of this metaanalysis warrant a large cohort study to develop selectin-based models targeting the risk of inflammatory complications.
Metrologic Traceability of Total Thyroxine Measurements in Human Serum: Efforts to Establish a Network of Reference Measurement Laboratories
Authors: Thienpont Linda M , Van Uytfanghe Katleen , Marriot John , Stokes Peter , Siekmann Lothar , Kessler Anja , Bunk David , Tai Susan 
Published: November 2004

Abstract
Background: Assuring/demonstrating metrologic traceability of in vitro diagnostics necessitates the availability of measurand-specific reference measurement systems (RMSs) and the possibility for industry to work with competent reference measurement laboratories (RMLs). Here we report the results of a European project to investigate the feasibility of developing a RMS for serum total thyroxine.
Methods: Four candidate RMLs (cRMLs) developed/implemented variants of a candidate reference measurement procedure (cRMP) based on isotope dilution–liquid chromatography–mass spectrometry. The sole constraint implemented was calibration with a common thyroxine primary calibrator. The RMPs were externally validated and assessed for comparability in round-robin trials using common samples, i.e., 5 lyophilized and 33 frozen native sera. At the same time, the performance of the cRMLs organized in a network was assessed. For uniform external quality assessment, common performance specifications were agreed on.
Results: All cRMLs performed the cRMPs with fulfillment of the predefined specifications: total and between-laboratory CVs ≤2.0% and 2.5%, respectively, and a systematic deviation ≤0.9%, estimated with a target assigned from the mean of means obtained by the cRMLs. The mean expanded uncertainty for value assignment to the native sera was 2.1%.
Conclusions: A network of cRMLs, with externally conformed competence to properly perform RMPs, has been established. Performance specifications were defined and will form the basis for admittance of new network members. A serum panel, successfully targeted during the validation process, is available for split-sample measurements with commercial routine measurement procedures. The model can now be used for other measurands for which traceability to the Système International d’Unités is needed.
Cysteine cathepsins in human cancer
Authors: Jedeszko Christopher , Sloane Bonnie F. 
Published: November 2004

AbstractProteases play causal roles in the malignant progression of human tumors. This review centers on the roles in this process of cysteine cathepsins, i.e., peptidases belonging to the papain family (C1) of the CA clan of cysteine proteases. Cysteine cathepsins, most likely along with matrix metalloproteases (MMPs) and serine proteases, degrade the extracellular matrix, thereby facilitating growth and invasion into surrounding tissue and vasculature. Studies on tumor tissues and cell lines have shown changes in expression, activity and distribution of cysteine cathepsins in numerous human cancers. Molecular, immunologic and pharmacological strategies to modulate expression and activity of cysteine cathepsins have provided evidence for a causal role for these enzymes in tumor progression and invasion. Clinically, the levels, activities and localization of cysteine cathepsins and their endogenous inhibitors have been shown to be of diagnostic and prognostic value. Understanding the roles that cysteine proteases play in cancer could lead to the development of more efficacious therapies.
A proteinase inhibitor from Caesalpinia echinata (pau-brasil) seeds for plasma kallikrein, plasmin and factor XIIa
Authors: Cruz-Silva Ilana , Gozzo Andrezza J. , Nunes Viviane A. , Carmona Adriana K. , Faljoni-Alario Adelaide , Oliva Maria Luiza V. , Sampaio Misako U. , Sampaio Claudio A. M. , Araujo Mariana S. 
Published: November 2004

Abstract

Caesalpinia echinata is a tree belonging to the Leguminosae family. The red color of the trunk, looking like burning wood (‘brasa’ in Portuguese), is the origin of the name Brazil. Seeds of leguminous plants contain high amounts of serine proteinase inhibitors that can affect different biological processes. Here we show that a protein isolated from seeds of C. echinata is able to inhibit enzymes that participate in blood coagulation and fibrinolysis. This inhibitor (CeKI) was purified to homogeneity by ion exchange and reversed-phase chromatography. SDS-PAGE indicated a single polypeptide chain with a molecular mass of 20 kDa. CeKI inhibits human plasma kallikrein (K
i=3.1 nM), plasmin (K
i=0.18 nM), factor XIIa (K
i=0.18 nM), trypsin (K
i=21.5 nM) and factor Xa (K
i=0.49 mM). CeKI inhibited kinin release from highmolecular- mass kininogen by kallikrein in vitro. The N-terminal sequence, determined by automatic Edman degradation, identified the inhibitor as a member of the Kunitz family. The secondary structure, determined by circular dichroism, is mainly a random coil followed by β-sheet structure. The action of CeKI on enzymes of the blood-clotting intrinsic pathway was confirmed by prolongation of the activated partial thromboplastin time.
Epoxy Resins
Authors: Pham Ha. Q. , Marks Maurice J. 
Published: November 2004

AbstractEpoxy resins are reactive intermediates used to produce a versatile class of thermosetting polymers. They are characterized by the presence of a three‐membered cyclic ether group commonly referred to as an epoxy group, 1,2‐epoxide, or oxirane. The most widely used epoxy resins are diglycidyl ethers of bisphenol A derived from bisphenol A and epichlorohydrin. The outstanding performance characteristics of the thermosets derived from bisphenol A epoxies are largely conveyed by the bisphenol A moiety (toughness, rigidity, and elevated temperature performance), the ether linkages (chemical resistance), and the hydroxyl and epoxy groups (adhesive agents). In addition to bisphenol A, other starting materials such as aliphatic glycols and both phenol ando‐cresol novolacs are used to produce specialty resins. Epoxy resins may also include epoxide‐bearing compounds based on aromatic amine, triazine, and cycloaliphatic backbones.A variety of reagents have been described for converting the liquid and solid epoxy resins to the cured state, which is necessary for the development of the ultimate end‐use properties. The curing agents or hardeners are categorized as either catalytic or coreactive. Catalytic curing agents initiate resin homopolymerization, either cationic or anionic, as a consequence of using a Lewis acid or base in the curing process. Coreactive curing agents are polyfunctional compounds typically possessing active hydrogens that are employed up to stoichiometric quantities with epoxy resins. The important classes of coreactive curing agents include multifunctional amines and their amide derivatives, polyphenols, polymeric thiols, polycarboxylic acids, anhydrides, phenol–formaldehyde novolacs and resoles, and amino–formaldehyde resins.The largest single use of epoxy resins is in the protective coatings market where high corrosion resistance and adhesion to substrates are important. Epoxies have gained wide acceptance in protective coatings and in electrical and structural applications because of their exceptional combination of properties such as toughness, adhesion, chemical and thermal resistance, and good electrical properties.
Emission Control, Automotive
Authors: Mooney John J. 
Published: November 2004

AbstractAutomotive exhaust gas composition depends on the fuel, the air‐fuel ratio, and on engine type, wear, temperature, etc. Exhaust control systems must be versatile enough to oxidize unburned fuel and partial oxidation products such as carbon monoxide, yet reduce nitrogen oxides, at both engine start‐up and during sustained engine operation. Emission control systems consist of a catalytic converter for the oxidation‐reduction of exhaust gases in conjunction with a fuel ignition system and oxygen sensor to regulate the air‐fuel ratio. Diesel engine emission control technology is discussed briefly.
Hydrazine and Its Derivatives
Authors: Rothgery Eugene F. 
Published: November 2004

AbstractHydrazine (diamide), N2H4, a colorless liquid having an ammoniacal odor, is the simplest diamine and unique in its class because of the NN bond.Hydrazine and its simple methyl and dimethyl derivatives have endothermic heats of formation and high heats of combustion. Hence, these compounds are used as rocket fuels. Other derivatives are used as gas generators and explosives. Hydrazine, a base slightly weaker than ammonia, forms a series of useful salts. As a strong reducing agent, hydrazine is used for corrosion control in boilers and hot‐water heating systems; also for metal plating, reduction of noble‐metal catalysts, and hydrogenation of unsaturated bonds in organic compounds. Hydrazine is also an oxidizing agent under suitable conditions. Having two active nucleophilic nitrogens and four replaceable hydrogens, hydrazine is the starting material for many derivatives, among them foaming agents for plastics, antioxidants, polymers, polymer cross‐linkers and chain‐extenders, as well as fungicides, herbicides, plant‐growth regulators, and pharmaceuticals. Hydrazine is also a good ligand; numerous complexes have been studied. Many heterocyclics are based on hydrazine, where the rings contain from one to four nitrogen atoms as well as other heteroatoms.The many advantageous properties of hydrazine assure continued‐commercial utility. Hydrazine is available in anhydrous form as well as aqueous solutions, typically 35, 51.2, 54.4, and 64 wt % N2H4(54.7, 80, 85, and 100% hydrazine hydrate).The commercially feasible processes involve partial oxidation of ammonia (or urea) using hypochlorite or hydrogen peroxide. Most hydrazine is produced by some variation of the Raschig process, which is based on the oxidation of ammonia using alkaline hypochlorite.Hydrazine is toxic and readily absorbed by oral, dermal, or inhalation routes of exposure.
Mapping nonverbal IQ in young boys with fragile X syndrome
Authors: Skinner Martie , Hooper Stephen , Hatton Deborah D. , Roberts Jane , Mirrett Penny , Schaaf Jennifer , Sullivan Kelly , Wheeler Anne , Bailey Donald B. 
Published: November 2004

AbstractThis study examines the developmental changes in nonverbal intellectual functioning evident in males with fragile X syndrome (FXS) measured by the Leiter International Performance Scales‐Revised (Leiter‐R). The Leiter‐R provides both IQ scores and associated growth scores which permit the examination of both age‐based IQ scores and overall intellectual growth. Participants were 45 males with full mutation FXS and ranged in age from 4.0 to 13.8 years. Each child was assessed annually using the Leiter‐R as part of a larger longitudinal battery for an average of 3.5 assessments per child and a range of 2–6 assessments, representing a total of 156 assessment occasions. Longitudinal analyzes of Leiter scores consisted primarily of hierarchical linear modeling, with the impact of chronological age, maternal education, fragile X mental retardation 1 protein (FMRP), autistic behaviors also being assessed. Findings revealed a significant linear decline in nonverbal IQ scores, with no effects of maternal education, autistic behaviors, or FMRP on mean level or rate of change in IQ scores over time. The decline slowed significantly around 8 years of age, but scores continued to decline into the 12th year of age. In contrast, a significant linear increase was observed in Leiter‐R growth scores, which was negatively influenced by autistic behaviors. The rate of increase did not change over time, and neither mean level nor rate of increase was influenced by maternal education or FMRP levels. These findings suggest that declines in IQ are the result of steady, but suboptimal intellectual growth, rather than a true deterioration in overall intellectual functioning. © 2004 Wiley‐Liss, Inc.
Congenital stationary night blindness: Report of an autosomal recessive family and linkage analysis
Authors: Abramowicz Marc J. , Ribai Pascale , Cordonnier Monique 
Published: November 2004

AbstractCongenital stationary night blindness (CSNB) is a group of rare, non‐progressive conditions of the retina characterized by abnormal rod function causing impaired night vision. Among them, the Schubert–Bornschein subgroup, itself divided into a complete and an incomplete form, is characterized by a specific electrophysiological pattern. Complete, Schubert–Bornschein CSNB is usually transmitted as a monogenic trait, and most familial cases result from mutations of the NYX gene located on the X chromosome. We report a very rare family with consanguineous, first‐cousin parents, where a son and a daughter are affected with this condition, indicating autosomal recessive inheritance. As the family was too small for genome‐wide linkage, we considered several candidate loci, including the sidekick SDK1 and SDK2 genes. The latter determine lamina‐specific connectivity in the retina, a histological substrate of the ON pathway implicated in complete, Schubert–Bornschein CSNB. Although linkage was excluded in our family, observations like the present one may lead to the identification of a new molecular cause for this condition. © 2004 Wiley‐Liss, Inc.
The 2×3 Toolbox of Organometallic Methods for Regiochemically Exhaustive Functionalization
Authors: Schlosser Manfred 
Published: November 2004

AbstractThis Review describes a concept aimed at rational and maximal structure proliferation. To this end, simple aromatic or heterocyclic starting materials, often bulk chemicals, are converted into all regionisomerically possible polar organometallic intermediates (mostly lithiated species), which then may be combined with any of the countless electrophiles to provide attractive new building blocks, particularly functionalized derivatives. The practical implementation relies on a set (“toolbox”) of sophisticated recipes developed by mechanistically guided modification of the two most prominent exchange methods used for the generation of polar organometallic compounds: hydrogen–metal and halogen–metal interconversion. These mutant methods (“old methods in a new outfit”) amplify the existing options for organic synthesis by ensuring maximum regioflexibility. At the same time they offer new insight into factors that govern organometallic reactivity and provide hints on how to alter or finetune this reactivity judiciously.
Monitoring congenital rubella embryopathy
Authors: Rittler Monica , López‐Camelo Jorge , Castilla Eduardo E. 
Published: November 2004

AbstractBACKGROUNDCurrently, all developed countries include rubella vaccination in their immunization programs, targeting the complete elimination of congenital rubella syndrome (CRS). In the underdeveloped world, where this severely disabling condition still exists, only a few countries have implemented vaccination policies, and almost no data on their effectiveness or on prevalence rates are available. The aims of the present work were to search for the best phenotype to be used as a sentinel for CRS in a large series of malformed newborns and to propose a CRS surveillance system, based only on clinical data.METHODSA total of 43 infants diagnosed as having CRS were obtained from 19,184 multimalformed infants, ascertained by the Latin‐American Collaborative Study of Congenital Malformations, World Health Organization (WHO) Collaborating Centre for the Prevention of Birth Defects (ECLAMC), over 3,883,165 consecutive births, between 1982 and 2003. They were distributed by country and the most frequent birth defects were identified. From the 19,184 multimalformed infants, all cases presenting the birth defects identified were selected. The sensitivity, specificity, and likelihood ratio (LR) in detecting CRS were determined for these birth defects, alone and in combination. The sample size of multimalformed infants required to detect different levels of increase in the rate of CRS was determined for three sentinel phenotypes.RESULTSThe rate of CRS was highest in Brazil. Based on the best possible combination of sensitivity, specificity, and LR, the dyad comprising eye anomalies and congenital heart defects was shown to be the most appropriate sentinel, with the lowest sample size required, to detect CRS in neonates.CONCLUSIONSA surveillance system for CRS, based on clinical data in newborns, is being proposed, in an attempt to monitor ongoing vaccination policies, aimed at eliminating CRS in developing countries. Birth Defects Research (Part A), 2004. © 2004 Wiley‐Liss, Inc.
Cell weight kinetics simulation in chemostat and batch culture of the rhodophyte Porphyridium cruentum
Authors: Muller‐Feuga Arnaud , Le Guédes Roland , Le Déan Loïc 
Published: November 2004

AbstractExperimental observations of cell size variations in the proliferating rhodophyte Porphyridium cruentum cultured under fully controlled conditions showed significant decreases from inoculation to a steady state in the chemostat with 0.23 d−1 dilution rate and to a minimum in batch, dropping in size by ratios of over 10. To numerically simulate these variations, we assumed that the cell is made up of two categories of components that behave differently during the interphase and mitosis. These have been called essential (EC) and accessory (AC) components. It is assumed that the cell divides once the EC have doubled in size, regardless of the AC's state. The experimental cell weight time courses were correctly simulated by a model of synchronous cell kinetics based on these assumptions. The EC's specific growth rate was 1.5 times that of the whole cell, when no limitation occurred. The increase in cell weight observed during batch cultures after nutrient exhaustion was suitably simulated by assuming that EC growth stops when a limiting nutrient is exhausted. Several parameters characterizing the cell kinetics were defined, particularly the minimum minimorum EC or cell weight (26 and 15 pg for chemostat and batch, respectively), which was influenced by the cultivation method, and the maximum whole cell weight (224 to 244 pg), which depended on the inoculum's age. The influence of culture conditions on the amount of essential and accessory components contained in a cell was examined. A new approach was developed with respect to these compartments to determine the most suitable strategy and conduct a predictive approach for valuable molecule production. © 2004 Wiley Periodicals, Inc.