bluuebunny/crossref_metadata_2025 huggingface dataset:
Frontal lobe dementia with abnormal cholesterol metabolism and heterozygous mutation in sterol 27‐hydroxylase gene (CYP27)
Authors: Sugama S. , Kimura A. , Chen W. , Kubota S. , Seyama Y. , Taira N. , Eto Y.
Published: December 2002

Of the primary dementing disorders that cause frontotemporal dementia, the best‐known is Pick disease. We report on a 44‐year‐old woman with progressive frontal lobe dementia and spastic paraplegia. Examination revealed increased serum levels of cholestanol with abnormal cholesterol metabolism and a heterozygous mutation of the sterol 27‐hydroxylase gene (CYP27). Biochemical findings were compatible with cerebrotendinous xanthomatosis (CTX); however, the clinical manifestations were very dissimilar. To our knowledge, a symptomatic carrier of this mutation among CTX patients has not been reported. We speculate that the present patient has a previously undescribed neurodegenerative disease related to abnormal cholesterol metabolism with this heterozygous mutation.
Fluvoxamine and sleep disturbances in posttraumatic stress disorder
Authors: Neylan Thomas C. , Metzler Thomas J. , Schoenfeld Frank B. , Weiss Daniel S. , Lenoci Maryann , Best Suzanne R. , Lipsey Tami L. , Marmar Charles R.
Published: December 2002

This study assesses the efficacy of fluvoxamine treatment on different domains of subjective sleep quality in Vietnam combat veterans with chronic posttraumatic stress disorder (PTSD). Medically healthy male Vietnam theater combat veterans (N = 21) completed a 10‐week open label trial. Fluvoxamine treatment led to improvements in PTSD symptoms and all domains of subjective sleep quality. The largest effect was for dreams linked to the traumatic experience in combat. In contrast, generic unpleasant dreams showed only a modest response to treatment. Sleep maintenance insomnia and the item “troubled sleep” showed a large treatment response, whereas sleep onset insomnia improved less substantially. These therapeutic benefits contrast with published reports that have found activating effects of Selective Serotonin Reuptake Inhibitors on the sleep electroencephalogram.
Reconstructing trauma memories: A prospective study of “Amnesic” trauma survivors
Authors: Harvey Allison G. , Bryant Richard A.
Published: December 2002

The purpose of this study was to investigate memory for trauma in patients who were initially amnesic of the trauma as a result of mild traumatic brain injury (MTBI). Motor vehicle accident survivors who sustained a MTBI were assessed for their memory within 1‐month posttrauma (n = 79) and again at 2‐years post‐trauma (n = 50). Consistent with their brain injury, all patients reported significant amnesia of their accident at initial assessment. At 2‐years posttrauma, 40% were able to remember their accident. Reporting memory for the trauma was associated with shorter duration of posttraumatic amnesia. These findings suggest that people reconstruct memories of trauma in the absence of complete encoding of the experience. Possible mechanisms for memory reconstruction are considered.
Treatment of combat‐related nightmares using imagery rehearsal: A pilot study
Authors: Forbes David , Phelps Andrea , McHugh Tony
Published: December 2002

Posttraumatic nightmares are a hallmark of PTSD and distinct from general nightmares as they are often repetitive and faithful representations of the traumatic event. This paper presents data from a pilot study that examined the use of Imagery Rehearsal in treating combat‐related nightmares of 12 Vietnam veterans with PTSD. Three treatment groups, comprising 4 veterans in each, completed standardised treatment across 6 sessions. Treatment effects were investigated using nightmare diaries and established instruments, including the IES‐R, BDI, BAI, and SCL‐90‐R. The data demonstrate significant reductions in nightmares targeted, and improvements in PTSD and comorbid symptomatology. The paper recommends that, on the basis of the promising preliminary data, a randomised control trial be established to assess imagery ability and attidude toward nightmares.
Growth Phenomena — Algebraic and Geometric Descriptions
Authors: Jamiołkowski Andrzej
Published: December 2002

An enormous variety of nonlinear dynamical systems can be — by suitable introduction of new coordinates — represented in the form of polynomial systems and then can be reduced to Volterra systems, where the nonlinearities are at most quadratic. In this paper, we discuss a link between systems of differential equations with homogeneous quadratic polynomial vector fields and non-associative algebras on the one hand and the question of representation of such systems as geodesics in some Finsler spaces on the other hand.
On Entangled Information and Quantum Capacity
Authors: Belavkin Viacheslav P.
Published: December 2002

The pure quantum entanglement is generalized to the case of mixed compound states to include the classical and quantum encodings as particular cases. The true quantum entanglements are characterized as transpose-CP but not CP maps. The entangled information is introduced as the relative entropy of the mutual and the input state and total information of the entangled states leads to two different types of entropy for a given quantum state: the von Neumann entropy, which is achieved as the supremum of the information over all c-entanglements, and the true quantum entropy, which is achieved at the standard entanglement. The q-capacity, defined as the supremum over all entanglements, doubles the c-capacity in the case of the simple algebra. The conditional q-entropy is positive, and q-information of a quantum channel is additive.
Pseudorandom Number Generators Based on Chaotic Dynamical Systems
Authors: Szczepański Janusz , Kotulski Zbigniew
Published: December 2002

Pseudorandom number generators are used in many areas of contemporary technology such as modern communication systems and engineering applications. In recent years a new approach to secure transmission of information based on the application of the theory of chaotic dynamical systems has been developed. In this paper we present a method of generating pseudorandom numbers applying discrete chaotic dynamical systems. The idea of construction of chaotic pseudorandom number generators (CPRNG) intrinsically exploits the property of extreme sensitivity of trajectories to small changes of initial conditions, since the generated bits are associated with trajectories in an appropriate way. To ensure good statistical properties of the CPRBG (which determine its quality) we assume that the dynamical systems used are also ergodic or preferably mixing. Finally, since chaotic systems often appear in realistic physical situations, we suggest a physical model of CPRNG.
Variable clinical presentation in lysosomal storage disorders
Authors: Beck M.
Published: December 2002

Summary: Extensive clinical heterogeneity is seen in lysosomal storage disorders, regarding the age of onset and severity of symptoms, the organs involved, and effects on the central nervous system. A broad phenotypic spectrum is seen, for example, in mucopolysaccharidosis type I (Hurler/Scheie disease), Gaucher disease, the severalforms of GM2‐gangliosidosis and the different manifestations of β‐galactosidasedeficiency (GM1‐gangliosidosis and Morquio disease type B). Variable clinical expression of the same enzyme defect is not well understood. The presence of different mutations is only part of the explanation, as intrafamilial variability is observed in many cases. Other mechanisms, for example the effect of specific activators, may also have an influence on phenotype.
A case of PDH‐E1α mosaicism in a male patient with severe metabolic lactic acidosis
Authors: Seyda A. , Chun K. , Packman S. , Robinson B. H.
Published: December 2002

We have characterized a novel mutation in a male patient that affects the coding sequence of PDH‐E1α gene and changes arginine‐141 to a leucine. This nucleotide substitution was found in about 75% of the studied DNA (fibroblasts, liver and muscle), a scenario that would indicate a case of E1α mosaicism in a male patient. When the mutant E1α protein was expressed in human skin fibroblasts with zero endogenous pyruvate dehydrogenase complex activity and E1α protein expression, no significant restoration of activity was recorded, in contrast to the wild‐type cDNA, even though both wild‐type and mutant protein levels were comparable. We concluded that the R141L mutation is a severe one and that it must have occurred in one of the E1α alleles during early embryogenesis.
Neuroleptic malignant syndrome during zuclopenthixol therapy in X‐linked cerebral adrenoleukodystrophy
Authors: Rubio‐Gozalbo M. E. , van Waardenburg D. A. , Forget P. P. , Spaapen L. J. M. , Verrips A. , Vroomen P. C. A. J.
Published: December 2002

An 8 year‐old boy with X‐ALD under treatment with simvastatin developed a severe adverse reaction when the dose of his other medication, zuclopenthixol was increased. Both drugs were withdrawn after a diagnosis of neuroleptic malignant syndrome was made.
Identification of novel CBFA1/RUNX2 mutations causing cleidocranial dysplasia
Authors: Bergwitz C. , Prochnau A. , Mayr B. , Kramer F.‐J. , Rittierodt M. , Berten H.‐L. , Hausamen J.‐E. , Brabant G.
Published: December 2002

Core binding factor A1 (CBFA1/RUNX2) is a runt‐like transcription factor essential for osteoblast differentiation. Haplotype insufficiency causes cleidocranial dysplasia (CCD), a syndrome featuring supernumerary tooth buds, delayed tooth eruption, patent fontanels, Wormian bones, short stature, dysplasia of the clavicles, growth retardation and hypoplasia of the distal phalanges. We identified novel CBFA1/RUNX2 mutations after PCR and direct sequencing of patient leukocyte DNA. In family 1 mother and son are affected by CCD. Both carry the missense mutation R190W (CGG > TGG). This nucleotide change introduced a BsmI restriction site, which was used to independently confirm the mutation. It was absent in healthy members of the family. Family 2, in which father and daughter are affected by CCD, shows a deletion of nucleotide C821. This deletion causes a frameshift mutation with premature stop after the insertion of 18 aberrant amino acids. Healthy family members did not have this mutation. The clavicular dysplasia was more pronounced with the R190W mutation, while the bone density was markedly reduced in individuals with either mutation, suggesting a previously underemphasized increased risk for osteoporosis in CCD.
“It's the Day‐to‐Day Living That Matters”: The Meaning and Process of Community in the Lives of a Couple with Significant Psychiatric Disabilities
Authors: Royce-Davis Joanna C.
Published: December 2002

This study attempts to define and describe the experience and process of community and community participation using a qualitative case study of a couple labeled with significant psychiatric disabilities. Findings indicate that important influences on perceptions and the process of community belonging include (a) the opportunity to personally define the meaning, limitations, and level of care associated with receiving a psychiatric label; (b) a reciprocal, central relationship; and (c) recognized opportunities for intentional participation in and access to meaningful relationships with other community members, including in the role of coworker or colleague.
Plasma glutamine and ammonia concentrations in ornithine carbamoyltransferase deficiency and citrullinaemia
Authors: Wilson C. J. , Lee P. J. , Leonard J. V.
Published: December 2002

A retrospective review of the plasma ammonia and glutamine concentrations during the long‐term management of 7 patients with ornithine carbamoyltransferase (OCT) deficiency and three with citrullinaemia is presented. The relationship between the plasma concentrations of ammonia and glutamine is not a simple linear one and there are significant differences between the two disorders. Patients with citrullinaemia tend to have higher plasma ammonia concentrations for a given plasma glutamine concentration compared to those with OCT deficiency. The possible reasons for these differences and the implications for management are discussed.
Expression of Winged Bean Basic Agglutinin in Spodoptera frugiperda Insect Cell Expression System
Authors: Srinivas V. R. , Bachhawat-Sikder Kiran , Habib Saman , Hasnain Seyed E. , Surolia Avadhesha
Published: December 2002

In this paper we report the successful expression of the winged bean basic agglutinin (WBA I) in insect cells infected with a recombinant baculovirus carrying the WBA I gene and its characterization in terms of its carbohydrate binding properties. The expressed protein appears to have a lower molecular weight than the native counterpart which is consistent with the lack of glycosylation of the former. Moreover, the expressed protein maintains its dimeric nature. Hence, a role for glycosylation in modulation of dimerization of WBA I is ruled out unlike Erythrina corallodendron (EcorL). Despite this the protein is active, with its sugar specificity unaltered.
Mitochondrial Uncoupling Proteins in Mammals and Plants
Authors: Borecký Jirí , Maia Ivan G. , Arruda Paulo
Published: December 2002

Uncoupling proteins (UCPs) belong to a distinct cluster of the mitochondrial anion carrier family. Up to five different uncoupling protein types were found in mitochondria of mammals and plants, and recently in fishes, fungi and protozoa. They exhibit a significantly conserved structure with several motifs specific to either the whole cluster or protein type. Uncoupling proteins, as well as the whole mitochondrial anion carrier gene family, probably emerged in evolution before the separation of animal, fungi, and plant kingdoms and originate from an anion/nucleotide or anion/anion transporter ancestor. Mammalian UCP1, UCP2, UCP3, and plant uncoupling proteins pUCP1 and pUCP2 are similar and seem to form one subgroup, whereas UCP4 and BMCP1 belong to a different group. Molecular, biochemical, and phylogenic data suggest that UCP2 could be considered as an UCP-prototype. UCP1 plays its biological role mainly in the non-shivering thermogenesis while the role of the other types is unknown. However, hypotheses have suggested that they are involved in the general balance of basic energy expenditure, protection from reactive oxygen species, and, in plants, in fruit ripening and seed ontogeny.
The Discovery of an Uncoupling Mitochondrial Protein in Plants
Authors: E. Vercesi Anibal
Published: December 2002

This paper describes peculiar properties of plant mitochondria and summarizes the experiments that led to the discovery of an uncoupling protein in these mitochondria. Recent advances in the study of the biochemical and physiological properties as well as on genes encoding plant uncoupling proteins are described in articles by Borecky et al., Jezek et al., and Jarmuszkiewicz et al. in this issue.
A pH-sensitive histidine residue as control element for ligand release from HLA-DR molecules
Authors: Rötzschke Olaf , Lau Julie M. , Hofstätter Maria , Falk Kirsten , Strominger Jack L.
Published: December 2002

Class II MHC molecules undergo conformational changes on shifts of the pH. As a consequence, low-affinity peptides tightly bound at pH 7.0 can be released at pH 5.0. The imidazole group of histidine is the only amino acid side chain affected within this range. At pH 5.0 the group is positively charged, polar, and hydrophilic, whereas at pH 7.4 it is neutral, apolar, and hydrophobic. In this study, we used soluble forms of HLA-DR and substituted conserved histidine residues with tyrosine, an isosteric analogue to the uncharged form of histidine. The goal of this substitution was to identify crucial His residues by an increase in pH stability of the ligand complex. HLA-DM-mediated release experiments revealed that substitution of His-33 in the α
1
domain of the HLA-DR molecule almost doubled the half-life of HLA-DR1/class II-associated invariant-chain peptide complexes. The divergence in the off-rate of WT and H33Y mutated complex was strictly pH-dependent and correlated with the theoretical titration curve of the imidazole group. For both HLA-DR1 and HLA–DR4 molecules the mutation resulted in a shift of class II-associated invariant-chain peptide release curves by up to 0.5 pH units. His-33α1 is present in all HLA-DR and H-2E molecules. It connects the α
1
and α
2
domains in its noncharged form by hydrophobic interactions with residue Val-136α2. It is located in close proximity to the putative interface with HLA-DM and may function as a pH-sensitive “button,” which is closed at pH 7.0 but opens below pH 6.0 to allow conformational transitions necessary for ligand exchange.
Interaction of pollinators and herbivores on plant fitness suggests a pathway for correlated evolution of mutualism- and antagonism-related traits
Authors: Herrera Carlos M. , Medrano Mónica , Rey Pedro J. , Sánchez-Lafuente Alfonso M. , García María B. , Guitián Javier , Manzaneda Antonio J.
Published: December 2002

Different kinds of plant–animal interactions are ordinarily studied in isolation, yet considering the combined fitness effects of mutualistic and antagonistic interactions is essential to understanding plant character evolution. Functional, structural, or phylogenetic associations between attractive and defensive traits may be nonadaptive or result from correlational selection on sets of herbivory- and pollination-linked traits. Nonadditivity of fitness effects of mutualists and antagonists, a requisite for correlational selection, was experimentally tested in the field. We created experimental populations of the insect-pollinated perennial herb,
Helleborus foetidus
, at 16 different locations distributed among three regions in the Iberian Peninsula. Plants experienced one of four possible selective regimes generated by independently weakening the effects of pollinators and herbivores (flower and fruit predators) according to a two-way fully factorial design. Effects were assessed in terms of number of next-generation offspring recruited per mother plant under natural field conditions. Differences among
H. foetidus
plants in the strength of their interactions with pollinators and herbivores translated into differential fitness, as measured in terms of recruited offspring, and subsequent changes in plant population densities. A strong, geographically consistent nonadditivity in the fitness consequences of pollinators and herbivores was found also. Plants possessing the particular combination of “traits” simultaneously enhancing pollination and escape from herbivores enjoyed a disproportionate fitness advantage over plants possessing any of the other three possible “trait” combinations. Results suggest a simple, possibly widespread ecological pathway favoring the adaptive correlated evolution of mutualism- and antagonism-related plant traits in pollinator-dependent plants suffering intense flower and fruit herbivory.
CUL7: A DOC domain-containing cullin selectively binds Skp1⋅Fbx29 to form an SCF-like complex
Authors: Dias Dora C. , Dolios Georgia , Wang Rong , Pan Zhen-Qiang
Published: December 2002

Selective protein degradation targeted by members of the F-box protein family plays pivotal roles in cell biology. It is widely accepted that an F-box protein directs substrate ubiquitination within a Skp1⋅CUL1⋅F-box protein⋅ROC1 (SCF-ROC1) E3 ubiquitin ligase complex. This assembly utilizes the CUL1 molecular scaffold, allowing the F-box protein to position its bound substrate for ubiquitination by a ROC1-recruited E2-conjugating enzyme. Here, we describe an alternative mechanism for assembling an F-box protein-based E3 complex through a previously uncharacterized cullin, CUL7, identified by mass spectrometry as a ROC1-interacting protein. CUL7 is a large polypeptide containing a cullin domain, which is responsible for ROC1 binding, and a DOC domain, which is also present in the anaphase-promoting complex. Remarkably, CUL7 assembles an SCF-ROC1-like E3 ubiquitin ligase complex consisting of Skp1, CUL7, the Fbx29 F-box protein, and ROC1. In contrast to CUL1 that binds Skp1 by itself, CUL7 interacts with the Skp1⋅Fbx29 complex, but not with Skp1 alone. Strikingly, CUL7 selectively interacts with Skp1⋅Fbx29 but not with Skp1⋅βTRCP2 or Skp1⋅Skp2. Thus, CUL7 may define a previously uncharacterized, Fbx29-mediated, and ubiquitin-dependent proteolysis pathway.
ARF
mutation accelerates pituitary tumor development in
Rb
+/− mice
Authors: Tsai Kenneth Y. , MacPherson David , Rubinson Douglas A. , Nikitin Alexander Yu. , Bronson Roderick , Mercer Kim L. , Crowley Denise , Jacks Tyler
Published: December 2002

Mice heterozygous for the retinoblastoma (
Rb
) tumor suppressor gene develop pituitary and thyroid tumors with high penetrance. We demonstrate here that loss of the
ARF
tumor suppressor strongly accelerates intermediate lobe pituitary tumorigenesis in
Rb
heterozygous mice. These effects in the pituitary are greater than those conferred by
p53
loss in that
Rb
+/−;
ARF
−/− mice display significantly more early atypical lesions than
Rb
+/−;
p53
−/− mice. Also,
Rb
+/−;
ARF
−/− compound mutants do not develop many of the novel tumors or precancerous lesions seen in
Rb
+/−;
p53
−/− compound mutants. Although complete loss of
ARF
expression is not obligatory for pituitary tumorigenesis in
Rb
+/− mice, alterations of the
ARF
locus are observed in tumors from
Rb
+/−;
ARF
+/− mice, consistent with a selective advantage of
ARF
inactivation in this context. We conclude that inactivation of
ARF
acts more broadly than that of
p53
in connecting abrogation of the
Rb
pathway to tumorigenesis.
Initiation factor eIF5B catalyzes second GTP-dependent step in eukaryotic translation initiation
Authors: Lee Joon H. , Pestova Tatyana V. , Shin Byung-Sik , Cao Chune , Choi Sang K. , Dever Thomas E.
Published: December 2002

Initiation factors IF2 in bacteria and eIF2 in eukaryotes are GTPases that bind Met-tRNA

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to the small ribosomal subunit. eIF5B, the eukaryotic ortholog of IF2, is a GTPase that promotes ribosomal subunit joining. Here we show that eIF5B GTPase activity is required for protein synthesis. Mutation of the conserved Asp-759 in human eIF5B GTP-binding domain to Asn converts eIF5B to an XTPase and introduces an XTP requirement for subunit joining and translation initiation. Thus, in contrast to bacteria where the single GTPase IF2 is sufficient to catalyze translation initiation, eukaryotic cells require hydrolysis of GTP by both eIF2 and eIF5B to complete translation initiation.
Associations between human disease genes and overlapping gene groups and multiple amino acid runs
Authors: Karlin Samuel , Chen Chingfer , Gentles Andrew J. , Cleary Michael
Published: December 2002

Overlapping gene groups (OGGs) arise when exons of one gene are contained within the introns of another. Typically, the two overlapping genes are encoded on opposite DNA strands. OGGs are often associated with specific disease phenotypes. In this report, we identify genes with OGG architecture and genes encoding multiple long amino acid runs and examine their relations to diseases. OGGs appear to be susceptible to genomic rearrangements as happens commonly with the loci of the DiGeorge syndrome on human chromosome 22. We also examine the degree of conservation of OGGs between human and mouse. Our analyses suggest that (
i
) a high proportion of genes in OGG regions are disease-associated, (
ii
) genomic rearrangements are likely to occur within OGGs, possibly as a consequence of anomalous sequence features prevalent in these regions, and (
iii
) multiple amino acid runs are also frequently associated with pathologies.
High-throughput screening for evidence of association by using mass spectrometry genotyping on DNA pools
Authors: Mohlke Karen L. , Erdos Michael R. , Scott Laura J. , Fingerlin Tasha E. , Jackson Anne U. , Silander Kaisa , Hollstein Pablo , Boehnke Michael , Collins Francis S.
Published: December 2002

To facilitate positional cloning of complex trait susceptibility loci, we are investigating methods to reduce the effort required to identify trait-associated alleles. We examined primer extension analysis by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry to screen single-nucleotide polymorphisms (SNPs) for association by using DNA pools. We tested whether this method can accurately estimate allele frequency differences between pools while maintaining the high-throughput nature of assay design, sample handling, and scoring. We follow up interesting allele frequency differences in pools by genotyping individuals. We tested DNA pools of 182, 228, and 499 individuals using 16 SNPs with minor allele frequencies 0.026–0.486 and allele frequency differences 0.001–0.108 that we had genotyped previously on individuals and 381 SNPs that we had not. Precision, as measured by the average standard deviation among 16 semidependent replicates, was 0.021 ± 0.011 for the 16 SNPs and 0.018 ± 0.008 for the 291/381 SNPs used in further analysis. For the 16 SNPs, the average absolute error in predicting allele frequency differences between pools was 0.009; the largest errors were 0.031, 0.028, and 0.027. We determined that compensating for unequal peak heights in heterozygotes improved precision of allele frequency estimates but had only a very minor effect on accuracy of allele frequency differences between pools. Based on these data and assuming pools of 500 individuals, we conclude that at significance level 0.05 we would have 95% (82%) power to detect population allele frequency differences of 0.07 for control allele frequencies of 0.10 (0.50).
Three mutations in sterol-sensing domain of SCAP block interaction with insig and render SREBP cleavage insensitive to sterols
Authors: Yabe Daisuke , Xia Zong-Ping , Adams Christopher M. , Rawson Robert B.
Published: December 2002

We report the isolation and characterization of a new line of mutant Chinese hamster ovary cells, designated SRD-5, that are resistant to 25HC, a potent suppressor of cleavage of sterol regulatory element-binding proteins (SREBPs) in mammalian cells. In SRD-5 cells, SREBPs are cleaved constitutively, generating transcriptionally active nuclear SREBP even in the presence of sterols. Sequence analysis of SREBP cleavage-activating protein (SCAP) transcripts from SRD-5 cells revealed the presence of a mutation in one SCAP allele that results in substitution of a conserved Leu by Phe at amino acid 315 within the sterol-sensing domain. Sterols fail to inhibit the packaging of SREBP/SCAP(L315F) complexes into budding vesicles
in vitro
. Sterols also fail to induce binding of SCAP(L315F) to insig-1 or insig-2, two proteins that function in the sterol-mediated retention of SREBP/SCAP complexes in the endoplasmic reticulum. Similar findings were observed for SCAP(D443N) and SCAP(Y298C), both of which cause a sterol-resistant phenotype. Thus, three different point mutations, each within the sterol-sensing domain of SCAP, prevent sterol-induced binding of SCAP to insig proteins and abolish feedback regulation of SREBP processing by sterols.
Dynamic assembly of MinD into filament bundles modulated by ATP, phospholipids, and MinE
Authors: Suefuji Kyoko , Valluzzi Regina , RayChaudhuri Debabrata
Published: December 2002

Accurate positioning of the division septum at the equator of
Escherichia coli
cells requires a rapid oscillation of MinD ATPase between the polar halves of the cell membrane, together with the division inhibitor MinC, under MinE control. The mechanism underlying MinD oscillation remains poorly understood. Here, we demonstrate that purified MinD assembles into protein filaments in the presence of ATP. Incubation with phospholipid vesicles further stimulates MinD polymerization. Addition of purified MinE in the presence of lipids promotes bundling of MinD filaments as well as their disassembly through activation of MinD ATPase. MinE thus provokes a net decay in the steady-state MinD polymer mass. Taken together, our results suggest that reversible MinD assembly modulated by MinE underlies the dynamic processing of positional information in
E. coli
to identify precisely the nascent site for cell division.
Z-DNA-binding proteins can act as potent effectors of gene expression
in
viv
o
Authors: Oh Doo-Byoung , Kim Yang-Gyun , Rich Alexander
Published: December 2002

The role of Z-DNA-binding proteins
in vivo
is explored in yeast. A conformation-specific yeast one-hybrid system is made in which formation of Z-DNA is studied near a minimal promoter site where it can be stabilized by negative supercoiling in addition to protein binding. Experiments were carried out with a Z-DNA-binding protein domain from the editing enzyme, double-stranded RNA adenosine deaminase 1. In the one-hybrid system, the reporter gene is activated when a Z-DNA-specific binding domain is fused with an activation domain and expressed
in vivo
. Significantly, it was found that even in the absence of the activation domain there is substantial transcription of the reporter gene if the Z-DNA-binding protein is expressed in the cell. This result suggests that Z-DNA formation in the promoter region induced or stabilized by a Z-DNA-binding protein can act as a
cis
-element in gene regulation. Related results have been found recently when the human chromatin-remodeling system converts a segment of DNA in the promoter region of the human colony-stimulating factor 1 gene into the left-handed Z-conformation.
Intermediate filament–membrane attachments function synergistically with actin-dependent contacts to regulate intercellular adhesive strength
Authors: Huen Arthur C. , Park Jung K. , Godsel Lisa M. , Chen Xuejun , Bannon Leslie J. , Amargo Evangeline V. , Hudson Tracie Y. , Mongiu Anne K. , Leigh Irene M. , Kelsell David P. , Gumbiner Barry M. , Green Kathleen J.
Published: December 2002

By tethering intermediate filaments (IFs) to sites of intercellular adhesion, desmosomes facilitate formation of a supercellular scaffold that imparts mechanical strength to a tissue. However, the role IF–membrane attachments play in strengthening adhesion has not been directly examined. To address this question, we generated Tet-On A431 cells inducibly expressing a desmoplakin (DP) mutant lacking the rod and IF-binding domains (DPNTP). DPNTP localized to the plasma membrane and led to dissociation of IFs from the junctional plaque, without altering total or cell surface distribution of adherens junction or desmosomal proteins. However, a specific decrease in the detergent-insoluble pool of desmoglein suggested a reduced association with the IF cytoskeleton. DPNTP-expressing cell aggregates in suspension or substrate-released cell sheets readily dissociated when subjected to mechanical stress whereas controls remained largely intact. Dissociation occurred without lactate dehydrogenase release, suggesting that loss of tissue integrity was due to reduced adhesion rather than increased cytolysis. JD-1 cells from a patient with a DP COOH-terminal truncation were also more weakly adherent compared with normal keratinocytes. When used in combination with DPNTP, latrunculin A, which disassembles actin filaments and disrupts adherens junctions, led to dissociation up to an order of magnitude greater than either treatment alone. These data provide direct in vitro evidence that IF–membrane attachments regulate adhesive strength and suggest furthermore that actin- and IF-based junctions act synergistically to strengthen adhesion.
Concentrative sorting of secretory cargo proteins into COPII-coated vesicles
Authors: Malkus Per , Jiang Feng , Schekman Randy
Published: December 2002

Here, we show that efficient transport of membrane and secretory proteins from the ER of Saccharomyces cerevisiae requires concentrative and signal-mediated sorting. Three independent markers of bulk flow transport out of the ER indicate that in the absence of an ER export signal, molecules are inefficiently captured into coat protein complex II (COPII)-coated vesicles. A soluble secretory protein, glycosylated pro–α-factor (gpαf), was enriched ∼20 fold in these vesicles relative to bulk flow markers. In the absence of Erv29p, a membrane protein that facilitates gpαf transport (Belden and Barlowe, 2001), gpαf is packaged into COPII vesicles as inefficiently as soluble bulk flow markers. We also found that a plasma membrane protein, the general amino acid permease (Gap1p), is enriched approximately threefold in COPII vesicles relative to membrane phospholipids. Mutation of a diacidic sequence present in the COOH-terminal cytosolic domain of Gap1p eliminated concentrative sorting of this protein.
Finding the common structure shared by two homologous RNAs
Authors: Perriquet O. , Touzet H. , Dauchet M.
Published: December 2002

Motivation: CARNAC is a new method for pairwise folding of RNA sequences. The program takes into account local similarity, stem energy, and covariations to produce the common folding. It can handle all RNA types, and has also been adapted to align a new homologous sequence along a reference structured sequence.

Results: Using different data sets, we show that CARNAC provides a good partial prediction for a wide range of sequences (16S ssu rRNA, RNase P RNA, viruses) with only two sequences. In presence of a whole family of sequences, we also show that CARNAC can be used to detect whether the sequences actually share the same structure.

Availability: CARNAC is available at the URLhttp://www.lifl.fr/~perrique/rna/

Contact: ; touzet@lifl.fr

* To whom correspondence should be addressed.
Predicting HIV drug resistance with neural networks
Authors: Drăghici Sorin , Potter R. Brian
Published: December 2002

Motivation: Drug resistance is a very important factor influencing the failure of current HIV therapies. The ability to predict the drug resistance of HIV protease mutants may be useful in developing more effective and longer lasting treatment regimens.

Methods: The HIV resistance is predicted to two current protease inhibitors, Indinavir and Saquinavir. The problem was approached from two perspectives. First, a predictor was constructed based on the structural features of the HIV protease–drug inhibitor complex. A particular structure was represented by its list of contacts between the inhibitor and the protease. Next, a classifier was constructed based on the sequence data of various drug resistant mutants. In both cases, self-organizing maps were first used to extract the important features and cluster the patterns in an unsupervised manner. This was followed by subsequent labelling based on the known patterns in the training set.

Results: The prediction performance of the classifiers was measured by cross-validation. The classifier using the structure information correctly classified previously unseen mutants with an accuracy of between 60 and 70%. Several architectures were tested on the more abundant sequence data. The best single classifier provided an accuracy of 68% and a coverage of 69%. Multiple networks were then combined into various majority voting schemes. The best combination yielded an average of 85% coverage and 78% accuracy on previously unseen data. This is more than two times better than the 33% accuracy expected from a random classifier.

Contact: sod@cs.wayne.edu

* To whom correspondence should be addressed.
Community Contexts of Human Welfare
Authors: Shinn Marybeth , Toohey Siobhan M.
Published: December 2002

This chapter identifies “context minimization error” as the tendency to ignore the impact of enduring neighborhood and community contexts on human behavior. The error has adverse consequences for understanding psychological processes and efforts at social change. The chapter describes a series of theoretical models of how neighborhoods and community settings are associated with various aspects of human welfare and reviews evidence of associations of contexts with health, psychological distress, risky behaviors, psychological attitudes, and child development. It suggests that many psychological processes may play out differently in different contexts and that contextual factors interact with sociocultural characteristics of individuals in predicting outcomes. People, in turn, can shape community contexts. A more sophisticated understanding of the effects of contexts depends on more sophisticated approaches to assessing them.
Biology, Context, and Developmental Inquiry
Authors: Kagan Jerome
Published: December 2002

[Figure: see text]

This chapter summarizes some of the conceptual changes in developmental research over the last half-century. These advances include an acknowledgment of the role of maturation; also recognized have been the need for positing distinct psychological structures, the influence of temperament, the malleability of the infant, the role of the local context, and the dynamic nature of the categories describing human psychological types.
Atomic‐Scale High‐Entropy Design for Superior Capacitive Energy Storage Performance in Lead‐Free Ceramics
Authors: Li Dengfeng , Zheng Zihao , Yang Bin , Chen Longyu , Shi Dean , Guo Jinming , Nan Ce‐Wen
Published: February 2025

Dielectric ceramics with high energy storage performance are crucial for the development of advanced high‐power capacitors. However, achieving ultrahigh recoverable energy storage density and efficiency remains challenging, limiting the progress of leading‐edge energy storage applications. In this study, (Bi1/2Na1/2)TiO3 (BNT) is selected as the matrix, and the effects of different A‐site elements on domain morphology, lattice polarization, and dielectric and ferroelectric properties are systematically investigated. Mg, La, Ca, and Sr are shown to enhance relaxation behavior by different magnitudes; hence, a high‐entropy strategy for designing local polymorphic distortions is proposed. Based on atomic‐scale investigations, a series of BNT‐based high‐entropy compositions are designed by introducing trace amounts of Mg and La to improve the electric breakdown strength and further disrupt the polar nanoscale regions (PNRs). A disordered polarization distribution and ultrasmall PNRs with a minimum size of ≈1 nm are detected in the high‐entropy ceramics. Ultimately, a high recoverable energy density of 10.1 J cm−3 and an efficiency of 90% are achieved for (Ca0.2Sr0.2Ba0.2Mg0.05La0.05Bi0.15Na0.15)TiO3. Furthermore, it displays a high‐power density of 584 MW cm−3 and an ultrashort discharge time of 27 ns. This work presents an effective approach for designing dielectric energy storage materials with superior comprehensive performance via a high‐entropy strategy.
In Situ Formation of Ripplocations in Hybrid Organic–Inorganic MXenes
Authors: Lagunas Francisco , Zhou Chenkun , Wang Di , Thakur Anupma , Anasori Babak , Talapin Dmitri V. , Hood Zachary D. , Klie Robert F.
Published: February 2025

Inorganic–organic hybrid MXenes (h‐MXenes) are a family of 2D transition metal carbides and nitrides functionalized with alkylimido and alkylamido surface groups. Using cryogenic and room temperature scanning transmission electron microscopy (STEM) and electron energy‐loss spectroscopy (EELS), it is shown that ripplocations, a form of a fundamental defect in 2D and layered structures, are abundant in this family of materials. Furthermore, detailed studies of electron probe sample interactions, focusing on structural deformations caused by the electron beam are presented. The findings indicate that at cryogenic temperatures (≈100 K) and below a specific dose threshold, the structure of h‐MXenes remains largely intact. However, exceeding this threshold leads to electron beam‐induced deformation through ripplocations. Interestingly, the deformation behavior, required dose, and resultant structure are highly dependent on temperature. At 100 K, it is demonstrated that the electron beam can induce ripplocations in situ with a high degree of precision.
Zinc Single‐Atom Catalysts Encapsulated in Hierarchical Porous Bio‐Carbon Synergistically Enhances Fast Iodine Conversion and Efficient Polyiodide Confinement for Zn‐I2 Batteries
Authors: Pei Li‐Hua , Xu Dong‐Ming , Luo Yan‐Zhu , Guo Shao‐Jie , Liu De‐Rong , Jiang Si‐Jie , Zhang Wen‐Jun , Cao Fei‐Fei
Published: February 2025

Aqueous zinc iodine (Zn‐I2) batteries have attracted attention due to their low cost, environmental compatibility, and high specific capacity. However, their development is hindered by the severe shuttle effect of polyiodides and the slow redox conversion kinetics of the iodine (I2) cathode. Herein, a long‐life Zn‐I2 battery is developed by anchoring iodine within an edible fungus slag‐derived carbon matrix encapsulated with Zn single‐atom catalysts (SAZn@CFS). The high N content and microporous structure of SAZn@CFS provide a strong iodine confinement, while the Zn‐N4‐C sites chemical interact with polyiodides effectively mitigating the iodine dissolution and the polyiodide shuttle effect. Additionally, the uniformly distributed SAZn sites significantly enhance the redox conversion efficiency of I−/I3−/I5−/I2, leading to improved capacity. At a high current density of 10 A g−1, the designed Zn‐I2 battery delivers an excellent capacity of 147.2 mAh g−1 and a long lifespan of over 80 000 cycles with 93.6% capacity retention. Furthermore, the battery exhibits stable operation for 3500 times even at 50 °C, demonstrating significant advances in iodine reversible storage. This synergistic strategy optimizes composite structure, offering a practical approach to meet the requirements of high‐performance Zn‐I2 batteries.
Engineering of Lignocellulose Pulp Binder for Ah‐Scale Lithium–Sulfur Batteries
Authors: Li Shengzhi , Chen Zhuzuan , Chen Jie , Luo Xintao , Qiu Xueqing , Qian Yong
Published: February 2025

Natural binders play attractive roles in stabilizing lithium–sulfur (Li–S) battery systems due to their polymeric skeleton and abundant functional structures, but the complex extraction and modification hinder the practical use. Here, lignocellulose, the unbleached product of the pulp industry, is directly developed as a robust binder in Li–S batteries. Benefiting from various oxygen‐containing functional groups woven strong hydrogen‐bonded network framework, robust mechanical stability, lithium polysulfide anchoring capacity, and high‐speed Li+ transport channel. The Li–S cell battery delivers an initial discharge capacity of 996 mAh·g⁻¹ at a current density of 0.5 C and can stably run 500 cycles. Moreover, an Ah‐scale pouch cell is constructed and delivers notable gravimetric and volumetric energy densities of 322 Wh·kg⁻¹ and 432 Wh·L⁻1, respectively. This work expands the application boundaries of bulk lignocellulose pulp in advanced energy storage systems.
Farmers' Perceived Transparency and Performance: A Moderated‐Mediation Model of Supply Chain Type, Buyer Type, and Relationship Quality
Authors: Vandenhaute Heidi , Gellynck Xavier , De Steur Hans
Published: February 2025

This study explores the potential of short food supply chains in addressing information asymmetries within the agri‐food chain. Drawing on data from 133 farmers in Flanders, Belgium, this research examines farmers' transparency perceptions regarding their buyers and evaluates their associations with relationship quality and perceived performance. The findings reveal a direct positive association between perceived transparency and perceived performance, with a substantial mediation through relationship quality. Moderated mediation analyses underscore the significant roles of supply chain type and buyer type in shaping these relationships. Notably, the association between transparency and performance is more pronounced for farmers engaged in short food supply chains and with privately owned buyers, contexts characterized by lower transparency perceptions. This highlights the potential benefits of enhanced transparency, particularly in such farmer–buyer relationships. This study emphasizes the importance for researchers, policymakers, and stakeholders to identify and strategically target practices aimed at increasing transparency in agri‐food supply chains.
Atomically dispersed Cu‐Zn tandem catalyst for efficient electrocatalytic reduction of CO2 to alcohols
Authors: Wang Hui , Jin Yifan , Jin Yaxin , Kuang Siyu , Yan Tianxiang , Wang Xinyue , Wang Xiao , Cui Wenquan , Zhang Sheng
Published: February 2025

Electrochemical carbon dioxide reduction reaction (CO2RR) is one of the most prospective strategies to achieve carbon neutrality. Multi‐carbon compound (C2+) products have higher commercial value and wider applications, among which ethanol is a widely used chemical feedstock and high energy density fuel. Here, we prepared nitrogen‐doped carbon nanofibers containing copper‐zinc double atoms using the electrospinning technique and controlled the content of both metal atoms by varying the calcination temperature. This catalyst exhibited ultra‐high selectivity for ethanol at low potentials. Ethanol selectivity at −0.3 V versus RHE was more than 60% with the total alcohol selectivity of over 80%. Meanwhile, we explored the ethanol production pathway by combining density‐functional theory (DFT) and ATR‐FTIR spectroscopy, and found that OCCO* intermediates were most abundant for the optimal ratio of Cu to Zn atoms, lowering the energetic barriers to ethanol formation, and thus improving the selectivity of ethanol production.
Cs+‐enabled stabilization of sub‐nanometer Pt‐bimetallic catalysts for propane dehydrogenation
Authors: Chai Shanshan , Xue Fan , Shao Yifan , Yao Yongbin , Li Jumeng , Wang Xi
Published: February 2025

Highly dispersed Pt‐bimetallic sub‐nanometer catalysts are crucial for efficient propane dehydrogenation (PDH), but synthesizing them with cost‐effective Pt precursors is challenging due to Pt's tendency to agglomerate, reducing catalytic activity. This study presents a Cs+‐mediated vacancy‐anchoring strategy to fabricate sub‐nanometer Pt‐bimetallic aggregates (CsPtM, M = Sn, V, Cr, Zn, Ga, Mn, Nb, Cu, and In) supported on Al₂O₃. Cs+ ions selectively occupy cationic vacancies on the Al₂O₃ surface, which serves to anchor Pt species, preventing their agglomeration and promoting the formation of sub‐nanoclusters through electrostatic interactions with [PtCl₆]2− precursor. Consequently, the CsPtM catalysts exhibit superior PDH performance compared to their PtM counterparts. Notably, CsPtSn demonstrates exceptional durability (450 h) and high propylene space–time yields (STY) after continuous operation. This enhanced performance is attributed to the strong metal‐support interaction induced by the vacancy‐anchoring strategy, which effectively suppresses metal sintering and preserves highly dispersed active sites.