bluuebunny/crossref_metadata_2025_split huggingface dataset:
Self-Assembly of Pulp Derivatives as Amphiphilic Compounds: Verification of Molecular Association and Complexation with Low and High Molecular Mass Compounds
Authors: Uraki Y. , Hanzaki A. , Hashida K. , Sano Y. 
Published: October 2004

Summary
Acetic acid pulps (AAPs) have been converted to amphiphiles by hydroxypropylation. The resulting
hydroxypropyl derivatives (HP-AAPs) formed self-aggregates in water. The interaction of HP-AAP molecules
was investigated by a viscometric method. The reduced viscosity (η
sp/c) of HP-AAP in both water
and chloroform was increased remarkably above a concentration of 0.1%. This implies that HP-AAP
molecules strongly interact with each other, caused by the hydrophobic interaction of residual lignins in
water and by hydrogen bonding of polysaccharides in chloroform. The self-aggregates adsorb water-soluble
fluorescent agents. The highest adsorption capacity was observed at the lowest pH among three pH
conditions investigated. They also solubilized sparingly water-soluble fluorescent agents in water in larger
amounts than did sodium dodecyl sulfate when used as a surfactant. These results suggest that the self-aggregates
of HP-AAP adsorb low molecular mass compounds as inclusion compounds. To clarify the
interaction of HP-AAP with biopolymers as high molecular mass compounds, the change in the activity
of papain, a protease, in phosphate buffer (pH 6.2) was examined in the presence and absence of HP-AAP.
HP-AAP acted as an inhibitor of papain at the initial stage of mixing. After mixing for 24 hours,
however, the papain activity was revived and preserved for 6 days. In contrast, the papain activity vanished
in the absence of HP-AAP after 24 hours because of autolysis. Therefore, HP-AAP protects papain
against autolysis, resulting from tight complexation with the biopolymer.
Formic Acid-Peroxyformic Acid Pulping of Aspen Wood: An Optimization Study
Authors: Abad S. , Santos V. , Parajó J. C. 
Published: October 2004

Summary

Populus tremula* Populus tremuloides wood samples were subjected to three-stage pulping in formic
acid media with hydrogen peroxide addition, according to the Milox process. By means of three incomplete,
second-order, centered, factorial designs, the effects of selected operational variables on the composition
and technical properties of pulps were assessed for optimization purposes. Under the best conditions
assayed, a pulp with 2.30% lignin, 87.0 % cellulose and 3.25% xylan was obtained at 53.2%
pulp yield. Good SCAN viscosity (826 ml/g), reduced Kappa number (9.0) and satisfactory alkaline
resistance (R-10 = 89.0; R-18 = 91.0) proved the potentiality of the selected pulp for dissolving pulp
production.
Marker paraneoplastischer neurologischer Erkrankungen / Markers of paraneoplastic neurologic disorders
Authors: Voltz Raymond 
Published: October 2004

Zusammenfassung

Zusammenfassung Paraneoplastische neurologische Erkrankungen sind relativ seltene, aber sicher häufiger übersehene Krankheitsbilder. Meist entsteht die neurologische Symptomatik, bevor ein Tumor diagnostiziert werden kann. Daher sind Marker für den Kliniker wichtig, welche einerseits die paraneoplastische Ätiologie eines neurologischen Syndroms bestätigen und andererseits helfen, den Begleittumor rasch zu diagnostizieren. Aufgrund der begleitenden Immunreaktion sind diese Tumore oft begrenzt und somit schwer zu diagnostizieren; die Tumortherapie stellt aber immer noch die wesentliche Therapiemaßnahme für die Patienten dar.
Diagnostic work-up of iron deficiency / Diagnostisches Vorgehen bei Eisenmangel
Authors: Metzgeroth Georgia , Hastka Jan 
Published: October 2004

Abstract

Abstract Iron deficiency (ID) is defined as a diminished total body iron content. Three degrees of severity have been defined: storage iron depletion (stage I), iron-deficient erythropoiesis (stage II), and iron deficiency anemia (stage III). When assessing the patient’s iron status, it is important to bear in mind that each of the various iron tests indicate something different in terms of ID. As they detect different stages of ID, the parameters efficiently complement each other to characterize the iron status in the individual patient. Of particular clinical interest are newer iron tests of the iron-deficient erythropoiesis: zinc protoporphyrin (ZPP), soluble transferrin receptor (sTfR), hypochrome erythrocytes (Hypo) and reticulocyte hemoglobin (CHr). Supervising the final step of the heme production, ZPP can be used as a reliable and inexpensive screening test of the whole iron metabolism. sTfR measurement is a useful tool to distinguish between real iron deficiency and functional iron deficiency in anemia of chronic disorders. Hypo and CHr seem to be the best parameters to diagnose ID in hemodialysis patients treated with recombinant human erythropoietin.
Durchflußzytometrische Typisierung der B-Zell Non-Hodgkin-Lymphome / Flow cytometric typing of B-cell Non Hodgkin lymphoma
Authors: Bettelheim Peter , Diem Heinz , Nebe Thomas 
Published: October 2004

Zusammenfassung

Zusammenfassung Die durchflußzytometrische Analyse von B-Zell-Lymphomen ist neben der zytologischen Beurteilung und der Histopathologie in der Diagnostik dieser vielfältigen Erkrankungen eine Routineuntersuchung. Sie eignet sich insbesondere bei den chronisch lymphoproliferativen Erkrankungen vom B-Zelltyp, bei denen zu einem hohen Prozentsatz Zellen des Lymphoms im Blut bzw. Knochenmark (KM) nachgewiesen werden können, zur näheren Klassifikation. Mittels eines Antikörperpanels können entsprechend der WHO-Klassifikation der Non-Hodgkin-Lymphome (NHL) vom B-Zelltyp bestimmte Entitäten voneinander abgegrenzt werden. Im folgenden Beitrag werden die Markerprofile der einzelnen Entitäten der B-zelligen NHL dargestellt und besprochen.
Die durchflußzytometrische Methode eignet sich aber nicht nur zur Subklassifikation von Lymphomen, sondern ist auch in der Lage, eine minimale Resterkrankung zu erkennen. Darüber hinaus weisen bestimmte Strukturen wie CD38 und ZAP-70 eine Assoziation mit dem klinischen Verlauf auf. Andere Moleküle wie CD20 und CD52 wiederum sind Targetstrukturen für therapeutische Ansätze.
Immunpathogenetische Subtypisierung der Multiplen Sklerose / Immunopathogenetic subtyping of multiple sclerosis
Authors: Berger Thomas , Reindl Markus 
Published: October 2004

Zusammenfassung

Zusammenfassung Multiple Sklerose ist keine einheitliche Erkrankung, sondern ein Formenkreis unterschiedlicher entzündlichdemyelinisierender ZNS-Erkrankungen. Die Variabilität des klinischen Verlaufs, verbunden mit fehlenden individuellen prognostischen Parametern, führt vor allem zu einem unterschiedlichen, letztlich nicht voraussagbaren Ansprechen auf therapeutische Interventionen. Daraus ergibt sich die Forderung nach einer differenzierten Subtypisierung der Patienten nach genetischen, klinischen, neuroradiologischen, neuropathologischen und neuroimmunologischen Gesichtspunkten. Damit wäre es erstmals möglich, Patienten nach einem differentialtherapeutischen Konzept spezifisch für eine individuelle Therapie zu stratifizieren und den Erfolg bisheriger Therapiestrategien zu steigern.
Anti-Glykolipid-Antikörper in der Diagnostik von Immunneuropathien / Anti-glycolipid antibodies in the diagnosis of immunoneuropathies
Authors: Wanschitz Julia , Deisenhammer Florian 
Published: October 2004

Zusammenfassung

Zusammenfassung Unter den nicht hereditären Formen von Neuropathien (NP) stellen die Immunneuropathien insofern eine Sonderform dar, als sie meistens einer kausalen Therapie zugeführt werden können. Die Diagnose stützt sich wie bei anderen Formen auf die klinische Untersuchung und den elektrophysiologischen Befund. Manche Immunneuropathien sind durch spezifische Antikörper gegen Nervenmembranbestandteile charakterisiert. Dazu zählen verschiedene Ganglioside, das Myelin-assoziierte Glykoprotein und Sulfatide. Zwar sind Immunneuropathien selten, es können aber bei bestimmten Formen in bis zu annähernd 100% der Fälle solche Antikörper nachgewiesen werden. Am häufigsten wird eine direkte ELISA-Methode angewandt, wobei insbesondere bei IgM-Antikörpern beachtet werden muss, dass solche wegen ihrer Kreuzreaktivität in niedrigen Titern auch bei der gesunden Bevölkerung mit hoher Frequenz vorkommen.
In dieser Arbeit werden die wichtigsten Typen von Immunneuropathien und die dazu gehörigen charakteristischen Laborbefunde beschrieben.
Joint Mapping of Quantitative Trait Loci for Multiple Binary Characters
Authors: Xu Chenwu , Li Zhikang , Xu Shizhong 
Published: October 2004

AbstractJoint mapping for multiple quantitative traits has shed new light on genetic mapping by pinpointing pleiotropic effects and close linkage. Joint mapping also can improve statistical power of QTL detection. However, such a joint mapping procedure has not been available for discrete traits. Most disease resistance traits are measured as one or more discrete characters. These discrete characters are often correlated. Joint mapping for multiple binary disease traits may provide an opportunity to explore pleiotropic effects and increase the statistical power of detecting disease loci. We develop a maximum-likelihood method for mapping multiple binary traits. We postulate a set of multivariate normal disease liabilities, each contributing to the phenotypic variance of one disease trait. The underlying liabilities are linked to the binary phenotypes through some underlying thresholds. The new method actually maps loci for the variation of multivariate normal liabilities. As a result, we are able to take advantage of existing methods of joint mapping for quantitative traits. We treat the multivariate liabilities as missing values so that an expectation-maximization (EM) algorithm can be applied here. We also extend the method to joint mapping for both discrete and continuous traits. Efficiency of the method is demonstrated using simulated data. We also apply the new method to a set of real data and detect several loci responsible for blast resistance in rice.
Using Molecular Sizes of Simple Sequence Repeats vs. Discrete Binned Data in Assessing Probability of Ancestry
Authors: Berry Donald A , Wright Deanne , Xie Chongqing , Seltzer Jon D , Smith J Stephen C 
Published: October 2004

Abstract
Most inferential methods for profiling genotypes based upon the use of DNA fragments use molecular-size data transcribed into discrete bins, which are intervals of DNA fragment sizes. Categorizing into bins is labor intensive with inevitable arbitrariness that may vary between laboratories. We describe and evaluate an algorithm for determining probabilities of parentage based on raw molecular-size data without establishing bins. We determine the standard deviation of DNA fragment size and assess the association of standard deviation with fragment size. We consider a pool of potential ancestors for an index line that is a hybrid with unknown pedigree. We evaluate the identification of inbred parents of maize hybrids with simple sequence repeat data in the form of actual molecular sizes received from two laboratories. We find the standard deviation to be essentially constant over the molecular weight. We compare these results with those of parallel analyses based on these same data that had been transcribed into discrete bins by the respective laboratories. The conclusions were quite similar in the two cases, with excellent performance using either binned or molecular-size data. We demonstrate the algorithm's utility and robustness through simulations of levels of missing and misscored molecular-size data.
On the Meaning and Existence of an Effective Population Size
Authors: Sjödin P , Kaj I , Krone S , Lascoux M , Nordborg M 
Published: October 2004

Abstract
We investigate conditions under which a model with stochastic demography or population structure converges to the coalescent with a linear change in timescale. We argue that this is a necessary condition for the existence of a meaningful effective population size. We find that such a linear timescale change is obtained when demographic fluctuations and coalescence events occur on different timescales. Simple models of population structure and randomly fluctuating population size are used to exemplify the ideas and provide an intuitive feel for the meaning of the conditions.
The LF1 Gene of Chlamydomonas reinhardtii Encodes a Novel Protein Required for Flagellar Length Control
Authors: Nguyen Rachel L , Tam Lai-Wa , Lefebvre Paul A 
Published: October 2004

Abstract
Flagellar length is tightly regulated in the biflagellate alga Chlamydomonas reinhardtii. Several genes required for control of flagellar length have been identified, including LF1, a gene required to assemble normal-length flagella. The lf1 mutation causes cells to assemble extra-long flagella and to regenerate flagella very slowly after amputation. Here we describe the positional cloning and molecular characterization of the LF1 gene using a bacterial artificial chromosome (BAC) library. LF1 encodes a protein of 804 amino acids with no obvious sequence homologs in other organisms. The single LF1 mutant allele is caused by a transversion that produces an amber stop at codon 87. Rescue of the lf1 phenotype upon transformation was obtained with clones containing the complete LF1 gene as well as clones that lack the last two exons of the gene, indicating that only the amino-terminal portion of the LF1 gene product (LF1p) is required for function. Although LF1 helps regulate flagellar length, the LF1p localizes almost exclusively in the cell body, with &lt;1% of total cellular LF1p localizing to the flagella.
The Amplification Model for Adaptive Mutation
Authors: Pettersson Mats E , Andersson Dan I , Roth John R , Berg Otto G 
Published: October 2004

Abstract
It has been proposed that the lac revertants arising under selective conditions in the Cairns experiment do not arise by stress-induced mutagenesis of stationary phase cells as has been previously assumed. Instead, these revertants may arise within growing clones initiated by cells with a preexisting duplication of the weakly functional lac allele used in this experiment. It is proposed that spontaneous stepwise increases in lac copy number (amplification) allow a progressive improvement in growth. Reversion is made more likely primarily by the resultant increase in the number of mutational targets—more cells with more lac copies. The gene amplification model requires no stress-induced variation in the rate or target specificity of mutation and thus does not violate neo-Darwinian theory. However, it does require that a multistep process of amplification, reversion, and amplification segregation be completed within ∼20 generations of growth. This work examines the proposed amplification model from a theoretical point of view, formalizing it into a mathematical framework and using this to determine what would be required for the process to occur within the specified period. The analysis assumes no stress-induced change in mutation rate and describes only the growth improvement occurring during the process of amplification and subsequent elimination of excess mutant lac copies. The dynamics of the system are described using Monte Carlo simulations and numerical integration of the deterministic equations governing the system. The results imply that the amplification model can account for the behavior of the system using biologically reasonable parameter values and thus can, in principle, explain Cairnsian adaptive mutation.
Ccr4-Not Complex mRNA Deadenylase Activity Contributes to DNA Damage Responses in Saccharomyces cerevisiae
Authors: Traven Ana , Hammet Andrew , Tenis Nora , Denis Clyde L , Heierhorst Jörg 
Published: October 2004

Abstract
DNA damage checkpoints regulate gene expression at the transcriptional and post-transcriptional level. Some components of the yeast Ccr4-Not complex, which regulates transcription as well as transcript turnover, have previously been linked to DNA damage responses, but it is unclear if this involves transcriptional or post-transcriptional functions. Here we show that CCR4 and CAF1, which together encode the major cytoplasmic mRNA deadenylase complex, have complex genetic interactions with the checkpoint genes DUN1, MRC1, RAD9, and RAD17 in response to DNA-damaging agents hydroxyurea (HU) and methylmethane sulfonate (MMS). The exonuclease-inactivating ccr4-1 point mutation mimics ccr4Δ phenotypes, including synthetic HU hypersensitivity with dun1Δ, demonstrating that Ccr4-Not mRNA deadenylase activity is required for DNA damage responses. However, ccr4Δ and caf1Δ DNA damage phenotypes and genetic interactions with checkpoint genes are not identical, and deletions of some Not components that are believed to predominantly function at the transcriptional level rather than mRNA turnover, e.g., not5Δ, also lead to increased DNA damage sensitivity and synthetic HU hypersensitivity with dun1Δ. Taken together, our data thus suggest that both transcriptional and post-transcriptional functions of the Ccr4-Not complex contribute to the DNA damage response affecting gene expression in a complex manner.
Convergent, RIC-8-Dependent Gα Signaling Pathways in the Caenorhabditis elegans Synaptic Signaling Network
Authors: Reynolds Nicole K , Schade Michael A , Miller Kenneth G 
Published: October 2004

Abstract
We used gain-of-function and null synaptic signaling network mutants to investigate the relationship of the Gαq and Gαs pathways to synaptic vesicle priming and to each other. Genetic epistasis studies using Gαq gain-of-function and null mutations, along with a mutation that blocks synaptic vesicle priming and the synaptic vesicle priming stimulator phorbol ester, suggest that the Gαq pathway generates the core, obligatory signals for synaptic vesicle priming. In contrast, the Gαs pathway is not required for the core priming function, because steady-state levels of neurotransmitter release are not significantly altered in animals lacking a neuronal Gαs pathway, even though these animals are strongly paralyzed as a result of functional (nondevelopmental) defects. However, our genetic analysis indicates that these two functionally distinct pathways converge and that they do so downstream of DAG production. Further linking the two pathways, our epistasis analysis of a ric-8 null mutant suggests that RIC-8 (a receptor-independent Gα guanine nucleotide exchange factor) is required to maintain both the Gαq vesicle priming pathway and the neuronal Gαs pathway in a functional state. We propose that the neuronal Gαs pathway transduces critical positional information onto the core Gαq pathway to stabilize the priming of selected synapses that are optimal for locomotion.
The Dlx Gene Complement of the Leopard Shark, Triakis semifasciata, Resembles That of MammalsSequence data from this article have been deposited with the EMBL/GenBank Data Libraries under accession nos. AY738118, AY738119, AY738120, AY738121, AY738122, AY738123.
Authors: Stock David W 
Published: October 2004

Abstract
Extensive gene duplication is thought to have occurred in the vertebrate lineage after it diverged from cephalochordates and before the divergence of lobe- and ray-finned fishes, but the exact timing remains obscure. This timing was investigated by analysis of the Dlx gene family of a representative cartilaginous fish, the leopard shark, Triakis semifasciata. Dlx genes encode homeodomain transcription factors and are arranged in mammals as three convergently transcribed bigene clusters. Six Dlx genes were cloned from Triakis and shown to be orthologous to single mammalian Dlx genes. At least four of these are arranged in bigene clusters. Phylogenetic analyses of Dlx genes were used to propose an evolutionary scenario in which two genome duplications led to four Dlx bigene clusters in a common ancestor of jawed vertebrates, one of which was lost prior to the diversification of the group. Dlx genes are known to be involved in jaw development, and changes in Dlx gene number are mapped to the same branch of the vertebrate tree as the origin of jaws.
Suppression of Histone H1 Genes in Arabidopsis Results in Heritable Developmental Defects and Stochastic Changes in DNA Methylation
Authors: Wierzbicki Andrzej T , Jerzmanowski Andrzej 
Published: October 2004

Abstract
Histone H1 is an abundant component of eukaryotic chromatin that is thought to stabilize higher-order chromatin structures. However, the complete knock-out of H1 genes in several lower eukaryotes has no discernible effect on their appearance or viability. In higher eukaryotes, the presence of many mutually compensating isoforms of this protein has made assessment of the global function of H1 more difficult. We have used double-stranded RNA (dsRNA) silencing to suppress all the H1 genes of Arabidopsis thaliana. Plants with a &gt;90% reduction in H1 expression exhibited a spectrum of aberrant developmental phenotypes, some of them resembling those observed in DNA hypomethylation mutants. In subsequent generations these defects segregated independently of the anti-H1 dsRNA construct. Downregulation of H1 genes did not cause substantial genome-wide DNA hypo- or hypermethylation. However, it was correlated with minor but statistically significant changes in the methylation patterns of repetitive and single-copy sequences, occurring in a stochastic manner. These findings reveal an important and previously unrecognized link between linker histones and specific patterns of DNA methylation.
The Dynamics of Transposable Elements in Structured Populations
Authors: Deceliere Grégory , Charles Sandrine , Biémont Christian 
Published: October 2004

Abstract
We analyzed the dynamics of transposable elements (TEs) according to Wright's island and continent-island models, assuming that selection tends to counter the deleterious effects of TEs. We showed that migration between host populations has no impact on either the existence or the stability of the TE copy number equilibrium points obtained in the absence of migration. However, if the migration rate is slower than the transposition rate or if selection is weak, then the TE copy numbers in all the populations can be expected to slowly become homogeneous, whereas a heterogeneous TE copy number distribution between populations is maintained if TEs are mobilized in some populations. The mean TE copy number is highly sensitive to the population size, but as a result of migration between populations, it decreases as the sum of the population sizes increases and tends to reach the same value in these populations. We have demonstrated the existence of repulsion between TE insertion sites, which is established by selection and amplified by drift. This repulsion is reduced as much as the migration rate is higher than the recombination rate between the TE insertion sites. Migration and demographic history are therefore strong forces in determining the dynamics of TEs within the genomes and the populations of a species.