bluuebunny/crossref_metadata_2025 huggingface dataset:
NO synthase 2 (
NOS2
) deletion promotes multiple pathologies in a mouse model of Alzheimer's disease
Authors: Colton C. A. , Vitek M. P. , Wink D. A. , Xu Q. , Cantillana V. , Previti M. L. , Van Nostrand W. E. , Weinberg J. B. , Dawson H.
Published: August 2006

Alzheimer's disease is characterized by two primary pathological features: amyloid plaques and neurofibrillary tangles. The interconnection between amyloid and tau aggregates is of intense interest, but mouse models have yet to reveal a direct interrelationship. We now show that NO may be a key factor that connects amyloid and tau pathologies. Genetic removal of NO synthase 2 in mice expressing mutated amyloid precursor protein results in pathological hyperphosphorylation of mouse tau, its redistribution to the somatodendritic compartment in cortical and hippocampal neurons, and aggregate formation. Lack of NO synthase 2 in the amyloid precursor protein Swedish mutant mouse increased insoluble β-amyloid peptide levels, neuronal degeneration, caspase-3 activation, and tau cleavage, suggesting that NO acts at a junction point between β-amyloid peptides, caspase activation, and tau aggregation.
Efficient generation of retinal progenitor cells from human embryonic stem cells
Authors: Lamba Deepak A. , Karl Mike O. , Ware Carol B. , Reh Thomas A.
Published: August 2006

The retina is subject to degenerative conditions, leading to blindness. Although retinal regeneration is robust in lower vertebrates, regeneration does not occur in the adult mammalian retina. Thus, we have developed efficient methods for deriving retinal neurons from human embryonic stem (hES) cells. Under appropriate culture conditions, up to 80% of the H1 line can be directed to the retinal progenitor fate, and express a gene expression profile similar to progenitors derived from human fetal retina. The hES cell-derived progenitors differentiate primarily into inner retinal neurons (ganglion and amacrine cells), with functional glutamate receptors. Upon coculture with retinas derived from a mouse model of retinal degeneration, the hES cell derived retinal progenitors integrate with the degenerated mouse retina and increase in their expression of photoreceptor-specific markers. These results demonstrate that human ES cells can be selectively directed to a neural retinal cell fate and thus may be useful in the treatment of retinal degenerations.
Autogenous and nonautogenous control of response in a genetic network
Authors: Camas Francisco M. , Blázquez Jesús , Poyatos Juan F.
Published: August 2006

Feedback-based control methods determine the behavior of cellular systems, an example being autogenous control, the regulation of production of a protein by itself. This control strategy was theoretically shown to be superior to an equivalent but nonautogenously regulated system when based on a repressor. Although some of its advantages were later confirmed with isolated synthetic circuits, the superiority of autogenous control in natural networks remains untested. Here, we use the SOS DNA repair system of
Escherichia coli
, where autogenous control is part of a single-input module, as a valid model to evaluate the functional advantages and biological implications of this mechanism. We redesign the control of its master regulator, the protein LexA, so that it becomes nonautogenously controlled. We compare both systems by combining high-resolution expression measurements with mathematical modeling. We show that the stronger stability associated with the autogenous regulation prevents false triggering of the response due to transient fluctuations in the inducing signal and that this control also reduces the system recovery time at low DNA damage. Likewise, autoregulation produces responses proportional to the damage signal level. In contrast, bacteria with LexA constitutively expressed induce maximal action even for very low damage levels. This excess in response comes at a cost, because it reduces comparatively the growth rate of these cells. Our results suggest that autogenous control evolved as a strategy to optimally respond to multiple levels of input signal minimizing the costs of the response and highlights reasons why master regulators of single-input modules are mostly autorepressed.
p38MAPK inhibition prevents disease in pemphigus vulgaris mice
Authors: Berkowitz Paula , Hu Peiqi , Warren Simon , Liu Zhi , Diaz Luis A. , Rubenstein David S.
Published: August 2006

Pemphigus vulgaris (PV) is a life-threatening autoimmune blistering skin disease characterized by detachment of keratinocytes (acantholysis). It has been proposed that PV IgG might trigger signaling and that this process may lead to acantholysis. Indeed, we recently identified a rapid and dose-dependent phosphorylation of p38 mitogen-activated protein kinase (p38MAPK) and heat shock protein (HSP) 27 after binding of PV antibodies to cultured keratinocytes. In human keratinocyte cultures, inhibitors of p38MAPK prevented PV IgG-induced phosphorylation of HSP27 and, more importantly, prevented the early cytoskeletal changes associated with loss of cell–cell adhesion. This study was undertaken to (i) determine whether p38MAPK and HSP25, the murine HSP27 homolog, were similarly phosphorylated in anin vivomodel of PV and (ii) investigate the potential therapeutic use of p38MAPK inhibition to block blister formation in an animal model of PV. We now report that p38MAPK inhibitors prevented PV blistering diseasein vivo. Targeting the end-organ by inhibiting keratinocyte desmosome signaling may be effective for treating desmosome autoimmune blistering disorders.
Unique self-palmitoylation activity of the transport protein particle component Bet3: A mechanism required for protein stability
Authors: Kümmel Daniel , Heinemann Udo , Veit Michael
Published: August 2006

Bet3 is a component of the transport protein particle complex involved in vesicular trafficking to and through the Golgi complex. X-ray structural analysis of human and mouse Bet3 revealed a hydrophobic tunnel inside the protein, which is occupied by a fatty acid linked to cysteine-68. We show here that Bet3 has strong self-palmitoylating activity. Incubation of purified Bet3 with [
3
H]palmitoyl-CoA (Pal-CoA) leads to a rapid and stoichiometric attachment of fatty acids to cysteine-68. Bet3 has an intrinsic affinity for Pal-CoA, and the palmitoylation reaction occurs at physiological pH values and Pal-CoA concentrations. Moreover, Bet3 is also efficiently palmitoylated at cysteine-68 inside vertebrate cells. Palmitoylation can occur late after Bet3 synthesis, but once the fatty acids are bound they are not removed, not even by disassembly of the Golgi complex. Narrowing the hydrophobic tunnel by exchange of alanine-82 with bulkier amino acids inhibits palmitoylation, both
in vitro
and inside cells, indicating that the fatty acid must insert into the tunnel for stable attachment. Finally, we show that palmitoylation of Bet3 plays a structural role. CD spectroscopy reveals that chemically deacylated Bet3 has a reduced melting temperature. As a consequence of its structural defect nonacylated Bet3 does not bind to TPC6, a further subunit of the transport protein particle complex, and is degraded inside cells.
Estrogen receptor signaling protects against immune suppression by UV radiation exposure
Authors: Widyarini Sitarina , Domanski Diane , Painter Nicole , Reeve Vivienne E.
Published: August 2006

The phytoestrogenic isoflavonoid equol is known to protect against solar-simulated UV radiation-induced inflammation, immunosuppression, and skin carcinogenesis. The mechanism may involve antioxidant actions, because equol not only is a radical scavenger but also enhances the induction of a relevant cutaneous antioxidant, metallothionein. However, this study in female hairless mice examined whether the estrogenicity of the isoflavonoid might be responsible. Protection by topically applied equol against photoimmune suppression was found to be strongly and dose-dependently inhibited by the estrogen receptor (ER) antagonist ICI 182,780. Furthermore, ICI 182,780 alone was found to significantly exacerbate immunosuppression resulting from solar-simulated UV radiation irradiation, suggesting a natural role for the ER in photoimmune protection. In support of this role, topical application of the physiological ligand 17-β-estradiol also provided dose-dependent photoimmune protection, inhibitable by ICI 182,780, that was attributed largely to the inactivation of the downstream actions ofcis-urocanic acid, an important endogenous immunosuppressive photoproduct. Thus, a hitherto unrecognized function of the ER as a normal photoprotective immune regulator in the skin was revealed. The relationship between equol and cutaneous metallothionein suggests an association of the ER with this inducible antioxidant in constraining the photoimmune-suppressed state and therefore in the prevention of the facilitation of photocarcinogenesis by this immunological defect. This role for the ER may underlie important gender-specific differences in UV-responsiveness that would reflect different needs for environmental photoprotection in males and females.
Comprehensive identification of
Drosophila
dorsal–ventral patterning genes using a whole-genome tiling array
Authors: Biemar Frédéric , Nix David A. , Piel Jessica , Peterson Brant , Ronshaugen Matthew , Sementchenko Victor , Bell Ian , Manak J. Robert , Levine Michael S.
Published: August 2006

Dorsal–ventral (DV) patterning of the
Drosophila
embryo is initiated by Dorsal, a sequence-specific transcription factor distributed in a broad nuclear gradient in the precellular embryo. Previous studies have identified as many as 70 protein-coding genes and one microRNA (miRNA) gene that are directly or indirectly regulated by this gradient. A gene regulation network, or circuit diagram, including the functional interconnections among 40 Dorsal target genes and 20 associated tissue-specific enhancers, has been determined for the initial stages of gastrulation. Here, we attempt to extend this analysis by identifying additional DV patterning genes using a recently developed whole-genome tiling array. This analysis led to the identification of another 30 protein-coding genes, including the
Drosophila
homolog of Idax, an inhibitor of Wnt signaling. In addition, remote 5′ exons were identified for at least 10 of the ≈100 protein-coding genes that were missed in earlier annotations. As many as nine intergenic uncharacterized transcription units were identified, including two that contain known microRNAs, miR-1 and -9a. We discuss the potential functions of these recently identified genes and suggest that intronic enhancers are a common feature of the DV gene network.
Differential regulation of phagosome maturation in macrophages and dendritic cells mediated by Rho GTPases and ezrin–radixin–moesin (ERM) proteins
Authors: Erwig Lars-Peter , McPhilips Kathleen A. , Wynes Murray W. , Ivetic Alexander , Ridley Anne J. , Henson Peter M.
Published: August 2006

Deletion of apoptotic cells from tissues involves their phagocytosis by macrophages, dendritic cells, and tissue cells. Although much attention has been focused on the participating ligands, receptors, and mechanisms of uptake, little is known of the disposition of the ingested cell within the phagosome. Here we show that uptake of apoptotic cells by macrophages or fibroblasts results in rapid phagosome maturation, whereas macrophage phagosomes containing Ig-opsonized target cells mature at a slower rate. The early maturation was shown to depend on activation of Rho acting through Rho kinase on ezrin–radixin–moesin proteins. Blockade of Rho signaling or inhibition of moesin both delayed maturation rates to those seen with opsonized targets. By contrast, phagosome maturation in dendritic cells was slower, similar between apoptotic and opsonized target cells, and unaffected by Rho inhibition. These observations have direct implications for the clearance of dying cells and the roles played by different phagocytes in antigen digestion and presentation.
A FoxO–Smad synexpression group in human keratinocytes
Authors: Gomis Roger R. , Alarcón Claudio , He Wei , Wang Qiongqing , Seoane Joan , Lash Alex , Massagué Joan
Published: August 2006

Transforming growth factor β (TGF-β) signals through activation of Smad transcription factors. Activated Smad proteins associate with different DNA-binding cofactors for the recognition and regulation of specific target genes. Members of the forkhead box O family (FoxO1, FoxO3, and FoxO4) play such a role in the induction of the cyclin-dependent kinase inhibitors p15Ink4b and p21Cip1. To delineate the organization of the TGF-β response in human keratinocytes, we defined the set of genes whose activation by TGF-β requires both FoxO and Smad functions. FoxO factors are shown to be essential for 11 of the 115 immediate gene activation responses to TGF-β in these cells. FoxO1, FoxO3, and FoxO4 act redundantly as mediators of these effects. Smad4, which functions as a partner of receptor-phosphorylated Smad2/3, is required for all of these responses. These results define a FoxO–Smad synexpression group or group of genes that are jointly induced by a common mechanism in response to TGF-β. In addition to
p15INK4b
and
p21CIP1
, these genes include mediators of stress responses (
GADD45A
,
GADD45B
, and
IER1
) and adaptive cell signaling responses (
CTGF
,
JAG1
,
LEMD3
,
SGK
,
CDC42EP3
, and
OVOL1
). Bioinformatic analysis of the promoter region of these genes reveals diverse configurations of Smad and FoxO binding elements, implying differences in the regulatory properties of this group of genes. Indeed, a subset of FoxO/Smad-dependent TGF-β gene responses additionally require the transcription factor CCAAT/enhancer-binding protein β. The composition of the FoxO–Smad synexpression group suggests that stress reactions and adaptive functions accompany the cytostatic response of keratinocytes to TGF-β.
Cyclophosphamide enhances glioma virotherapy by inhibiting innate immune responses
Authors: Fulci Giulia , Breymann Laura , Gianni Davide , Kurozomi Kazuhiko , Rhee Sarah S. , Yu Jianhua , Kaur Balveen , Louis David N. , Weissleder Ralph , Caligiuri Michael A. , Chiocca E. Antonio
Published: August 2006

Clinical trials are testing oncolytic viruses (OVs) as therapies for cancer. We have shown that animals that have brain tumors and are treated with a herpes simplex virus (HSV)-derived OV live significantly longer when cyclophosphamide (CPA) is preadministered. Here, we explore the mechanisms behind this finding. In a syngeneic rat glioma model, intratumoral HSV administration is associated with rapid increase of natural killer cells, microglia/macrophages (CD68+and CD163+), and IFN-γ. Pretreatment with CPA enhances HSV replication and oncolysis and reduces an HSV-mediated increase in CD68+and CD163+cells and intratumoral IFN-γ. Molecular imaging shows CPA pretreatment to inhibit HSV-induced infiltration of tumor-associated phagocytic cells. Our results reveal molecular and cellular mechanisms that inhibit intratumoral spread of HSV and suggest a therapeutic path for improving the efficacy of virotherapy as a treatment for cancer.
Sexual acquisition of beneficial symbionts in aphids
Authors: Moran Nancy A. , Dunbar Helen E.
Published: August 2006

A noted cost of mating is the risk of acquiring sexually transmitted infections that are detrimental to the recipient. But many microbial associates of eukaryotes are mutualistic, raising the possibility that sexual contact provides the opportunity to acquire symbionts that are beneficial. In aphids, facultative bacterial symbionts, which benefit hosts by conferring resistance to natural enemies or to heat, are transmitted maternally with high fidelity and are maintained stably throughout hundreds of parthenogenetic generations in the laboratory. Data from field populations indicate that horizontal transfer of these facultative symbionts is frequent, and transfections are readily achieved by microinjection or ingestion in artificial diet. However, no natural mechanism for the horizontal transfer of these symbionts has been identified. Here we demonstrate that during sexual reproduction, male-borne symbionts can be acquired by females and subsequently transferred to sexually and parthenogenetically produced progeny, establishing stable, maternally transmitted associations. In our experiments, sexually transmitted symbionts resulted in (
i
) infection of previously uninfected matrilines, (
ii
) a double infection in a matriline already bearing a different symbiont, and (
iii
) replacement of the maternal symbiont. We also observed some cases in which maternal symbionts failed to become established in sexually produced progeny. Microscopy indicated that symbionts were abundant in the male reproductive system, which demonstrates a natural route of nonmaternal transfer of insect symbionts. Because such transfer can generate coinfections, thereby creating opportunities for symbiont competition and recombination, paternal inheritance has major consequences for expectations regarding symbiont evolution.
Expanding retrieval practice: An effective aid to preschool children's learning
Authors: Fritz Catherine O. , Morris Peter E. , Nolan Debra , Singleton Jillian
Published: August 2006

The benefits of expanding retrieval practice for preschool children were explored in two experiments. In Experiment 1, three groups learned names for six plush toy pigs using expanding retrieval practice, a reward incentive, or a control condition. Reward did not significantly improve learning but retrieval practice doubled recall. In Experiment 2, three groups learned names to soft toys, comparing recall following massed elaborative study with either expanding retrieval practice or expanding re-presentation. Recall was tested after 1 minute, 1 day, and 2 days. A very large effect size ( d = 1.9) indicated the very considerable benefit from expanding retrieval practice over the elaboration condition. Comparison with the re-presentation condition suggested that half of the benefit of expanding retrieval practice came from spaced scheduling and half from retrieval practice. Expanding retrieval practice provides an effective method to improve learning by young children.
Duration of the initial TCR stimulus controls the magnitude but not functionality of the CD8+ T cell response
Authors: Prlic Martin , Hernandez-Hoyos Gabriela , Bevan Michael J.
Published: August 2006

CD8+ T cells only require a brief stimulation with antigen in vitro to divide and differentiate into effector and memory cells upon transfer in vivo. The efficiency of clonal expansion and the functional characteristics of memory cells derived from briefly stimulated cells are poorly defined. We developed a system that allowed us to examine programming entirely in vivo. This was achieved by rapidly killing peptide-pulsed DCs carrying a diphtheria toxin receptor transgene with timed injections of diphtheria toxin without altering the course of an accompanying infection. The magnitude of clonal expansion, but not the functionality of the effector cells, correlated directly with the duration of antigen exposure. Furthermore, memory T cells were capable of mounting a secondary response, regardless of the length of antigen encounter during the primary response. These results indicate that the duration of initial antigen encounter influences the magnitude of the primary response, but does not program responsiveness during the secondary challenge.
Reversal of HCN Channel Voltage Dependence via Bridging of the S4–S5 Linker and Post-S6
Authors: Prole David L. , Yellen Gary
Published: August 2006

Voltage-gated ion channels possess charged domains that move in response to changes in transmembrane voltage. How this movement is transduced into gating of the channel pore is largely unknown. Here we show directly that two functionally important regions of the spHCN1 pacemaker channel, the S4–S5 linker and the C-linker, come into close proximity during gating. Cross-linking these regions with high-affinity metal bridges or disulfide bridges dramatically alters channel gating in the absence of cAMP; after modification the polarity of voltage dependence is reversed. Instead of being closed at positive voltage and activating with hyperpolarization, modified channels are closed at negative voltage and activate with depolarization. Mechanistically, this reversal of voltage dependence occurs as a result of selectively eliminating channel deactivation, while retaining an existing inactivation process. Bridging also alters channel activation by cAMP, showing that interaction of these two regions can also affect the efficacy of physiological ligands.
The ties problem resulting from counting-based error estimators and its impact on gene selection algorithms
Authors: Zhou Xin , Mao K. Z.
Published: August 2006

Motivation: Feature selection approaches, such as filter and wrapper, have been applied to address the gene selection problem in the literature of microarray data analysis. In wrapper methods, the classification error is usually used as the evaluation criterion of feature subsets. Due to the nature of high dimensionality and small sample size of microarray data, however, counting-based error estimation may not necessarily be an ideal criterion for gene selection problem.

Results: Our study reveals that evaluating genes in terms of counting-based error estimators such as resubstitution error, leave-one-out error, cross-validation error and bootstrap error may encounter severe ties problem, i.e. two or more gene subsets score equally, and this in turn results in uncertainty in gene selection. Our analysis finds that the ties problem is caused by the discrete nature of counting-based error estimators and could be avoided by using continuous evaluation criteria instead. Experiment results show that continuous evaluation criteria such as generalised ‖w‖2 measure for support vector machines and modified Relief's measure for k-nearest neighbors produce improved gene selection compared with counting-based error estimators.

Availability: The companion website is at . The website contains (1) the source code of all the gene selection algorithms and (2) the complete set of tables and figures of experiments.

Contact:  ekzmao@ntu.edu.sg
Keystone meeting summary: ‘Adipogenesis, obesity, and inflammation’ and ‘Diabetes mellitus and the control of cellular energy metabolism, ’ January 21–26, 2006, Vancouver, Canada: Figure 1.
Authors: Corvera Silvia , Burkart Alison , Kim Ja-Young , Christianson Jennifer , Wang Zhao , Scherer Philipp E.
Published: August 2006

The dysregulation of specific cellular functions in adipocytes, muscle cells, β cells, and the liver leads to changes in systemic metabolic processes and ultimately to the pathophysiological manifestations that cause type 2 diabetes. The underlying cellular mechanisms are complex. The two meetings summarized here aimed to highlight the recent advances in our understanding of the molecular basis of feeding and nutrient storage and on the molecular consequences of obesity in terms of promoting risk for type 2 diabetes and cardiovascular disease.
The flagellar-specific transcription factor, σ28, is the Type III secretion chaperone for the flagellar-specific anti-σ28 factor FlgM
Authors: Aldridge Phillip D. , Karlinsey Joyce E. , Aldridge Christine , Birchall Christopher , Thompson Danielle , Yagasaki Jin , Hughes Kelly T.
Published: August 2006

The σ28 protein is a member of the bacterial σ70-family of transcription factors that directs RNA polymerase to flagellar late (class 3) promoters. The σ28 protein is regulated in response to flagellar assembly by the anti-σ28 factor FlgM. FlgM inhibits σ28-dependent transcription of genes whose products are needed late in assembly until the flagellar basal motor structure, the hook-basal body (HBB), is constructed. A second function for the σ28 transcription factor has been discovered: σ28 facilitates the secretion of FlgM through the HBB, acting as the FlgM Type III secretion chaperone. Transcription-specific mutants in σ28 were isolated that remained competent for FlgM-facilitated secretion separating the transcription and secretion-facilitation activities of σ
28. Conversely, we also describe the isolation of mutants in σ28 that are specific for FlgM-facilitated secretion. The data demonstrate that σ28 is the Type III secretion chaperone for its own anti-sigma factor FlgM. Thus, a novel role for a σ70-family transcription factor is described.
C. elegans GLA-3 is a novel component of the MAP kinase MPK-1 signaling pathway required for germ cell survival
Authors: Kritikou Ekaterini A. , Milstein Stuart , Vidalain Pierre-Olivier , Lettre Guillaume , Bogan Erica , Doukoumetzidis Kimon , Gray Phillip , Chappell Thomas G. , Vidal Marc , Hengartner Michael O.
Published: August 2006

During oocyte development in Caenorhabditis elegans, approximately half of all developing germ cells undergo apoptosis. While this process is evolutionarily conserved from worms to humans, the regulators of germ cell death are still largely unknown. In a genetic screen for novel genes involved in germline apoptosis in Caenorhabditis elegans, we identified and cloned gla-3. Loss of gla-3 function results in increased germline apoptosis and reduced brood size due to defective pachytene exit from meiosis I. gla-3 encodes a TIS11-like zinc-finger-containing protein that is expressed in the germline, from the L4 larval stage to adulthood. Biochemical evidence and genetic epistasis analysis revealed that GLA-3 participates in the MAPK signaling cascade and directly interacts with the C. elegans MAPK MPK-1, an essential meiotic regulator. Our results show that GLA-3 is a new component of the MAPK cascade that controls meiotic progression and apoptosis in the C. elegans germline and functions as a negative regulator of the MAPK signaling pathway during vulval development and in muscle cells.
Plasticity and expanding complexity of the hepatic transcription factor network during liver development
Authors: Kyrmizi Irene , Hatzis Pantelis , Katrakili Nitsa , Tronche Francois , Gonzalez Frank J. , Talianidis Iannis
Published: August 2006

Cross-regulatory cascades between hepatic transcription factors have been implicated in the determination of the hepatic phenotype. Analysis of recruitments to regulatory regions and the temporal and spatial expression pattern of the main hepatic regulators during liver development revealed a gradual increase in complexity of autoregulatory and cross-regulatory circuits. Within these circuits we identified a core group of six transcription factors, which regulate the expression of each other and the expression of other downstream hepatic regulators. Changes in the promoter occupancy patterns during development included new recruitments, release, and exchange of specific factors. We also identified promoter and developmental stage-specific dual regulatory functions of certain factors as an important feature of the network. Inactivation of HNF-4α in embryonic, but not in adult, liver resulted in the diminished expression of most hepatic factors, demonstrating that the stability of the network correlates with its complexity. The results illustrate the remarkable flexibility of a self-sustaining transcription factor network, built up by complex dominant and redundant regulatory motifs in developing hepatocytes.
Factor X deficiency: clinical manifestation of 102 subjects from Europe and Latin America with mutations in the factor 10 gene
Authors: HERRMANN F. H. , AUERSWALD G. , RUIZ‐SAEZ A. , NAVARRETE M. , POLLMANN H. , LOPACIUK S. , BATOROVA A. , WULFF K. ,   THE GREIFSWALD FACTOR X DEFICIENCY STUDY GROUP
Published: August 2006

Summary.  Inherited factor X deficiency (FXD) is a rare (1:1 000 000) recessive bleeding disorder. The clinical and laboratory phenotypes of FXD are poorly correlated and few regional studies on the genotype and the clinical manifestations of FXD are known. To understand the association between clinical manifestations and causative genotype, detailed evaluation of bleeding pattern in a high number of patients is needed. This international study analysed the phenotype and genotype of 102 subjects from Central Europe (Germany, Poland and Slovakia) and Latin America (Costa Rica and Venezuela) with causative mutations in the F10 gene, via sequencing. Twenty‐eight homozygous, seven compound‐heterozygous and 67 heterozygous FXD subjects were characterized. Twenty‐nine different causative mutations, including 15 novel mutations, were analysed. Spontaneous bleeding symptoms in 42 symptomatic individuals (26 homozygous, seven compound heterozygous and nine heterozygous) comprised easy bruising (55%), haematoma (43%), epistaxis (36%), haemarthrosis (33%), intracranial haemorrhage (ICH; 21%), and gastrointestinal (GI) haemorrhage (12%). The manifestation of bleeding symptoms in 9 of 67 (13%) symptomatic heterozygous subjects is described. The bleeding patterns of the enrolled patients showed differences that are associated with the types of F10 mutation, and the corresponding genotypes. The homozygous patients were evaluated for genotype–phenotype correlation. The results suggested that ICH seems to be associated with the F10 mutation Gly380Arg, and possibly with the mutations IVS7–1G > A and Tyr163delAT. A tentative association of other mutations to severe symptoms such as haemarthrosis and GI haemorrhage is reported. The severity of FXD, the genotype–phenotype association, and the results of regional studies are discussed.
Physical fitness, functional ability and quality of life in children with severe haemophilia: a pilot study
Authors: VAN DER NET J. , VOS R. C. , ENGELBERT R. H. H. , VAN DEN BERG M. H. , HELDERS P. J. M. , TAKKEN T.
Published: August 2006

Summary.  In the Netherlands comparable levels of sports‐participation between persons with haemophilia and healthy controls have been reported. This raises the question if children with haemophilia under the currently available prophylaxis do reach comparable levels of physical fitness and health‐related quality of life (HRQoL) as their healthy peers. The aim of this study was to investigate the level of physical fitness, functional ability and quality of life and to determine the feasibility to safely test the exercise capacity of boys with severe haemophilia A. Thirteen subjects participated in this study. Physical fitness was determined using the measurement of maximal oxygen uptake (VO2peak) attained during a graded maximal exercise test to volitional exhaustion. Joint health, physical activity levels and health‐related quality of life (Haemo‐Qol) were also measured. Mean VO2peak was 1.86 ± 0.77 L min−1 (Z‐score: −0.39 ± 1.61) which was not significantly different from reference values. Relative VO2peak was 47.42 ± 8.29 mL min−1 kg−1 (Z‐score: −0.52 ±1.43), which did not differ significantly from reference values either. One boy suffered a joint bleeding one day after the test. Haemo‐Qol scores in parents and children ranged from 3.2% to 36.7% (100% reflects poor outcome). Relationship between the child or parent reports of Haemo‐QoL and both absolute and relative VO2peak ranged from R = 0.00 and R = 0.4. Exercise testing in children with severe haemophilia A was a safe procedure. Patients with severe haemophilia A with good joint health and no limitations of activities have comparable physical fitness and physical active lifestyle with healthy peers and good HRQoL.
Reliability and construct validity of the compatible MRI scoring system for evaluation of haemophilic knees and ankles of haemophilic children. Expert MRI working group of the international prophylaxis study group
Authors: DORIA A. S. , BABYN P. S. , LUNDIN B. , KILCOYNE R. F. , MILLER S. , RIVARD G. E. , MOINEDDIN R. , PETTERSSON H.
Published: August 2006

Summary.  We tested the reliability and construct validity of the Compatible magnetic resonance imaging (MRI) scale for the evaluation of haemophilic knees and ankles and compared the diagnostic performance of MRI and plain film radiographs. Sagittal and coronal gradient‐echo 1.5‐T MR images of knees (n = 22) and ankles (n = 23) were obtained from boys (age range 4–16 years; mean 11 years) in two centres (Toronto, n = 26; Europe, n = 19). The MR images were independently read by four blinded radiologists on two occasions. Number of previous joint bleedings and laboratory level of severity of haemophilia were the reference standards for imaging assessment. Both components of the MRI scale demonstrated high inter‐ and intrareader intraclass correlation coefficients (progressive (P) scale, 0.91 and 0.94; additive (A) scale, 0.81 and 0.92 respectively). The correlation between the osteochondral domain of the MRI scale and patient's age was moderate. Otherwise, correlations between A‐ and P‐scales and clinical laboratory measurements were weak. The areas under the curve (AUCs) used for discrimination of disease severity were similar for the A‐ and P‐scales (AUCs used for mild disease, A‐scale, 0.72 ± 0.07; P‐scale, 0.69 ± 0.08; P = 0.23; AUCs for severe disease, A‐scale, 0.93 ± 0.05; P‐scale, 0.87 ± 0.08; P = 0.05). No differences were noted between the AUCs of the MRI and radiographic scales used for discrimination of late osteoarticular changes; MRI scales performed better for discrimination of early changes. In conclusion, both MRI scales demonstrated excellent reliability, poor convergent validity, and moderate and excellent validity for discrimination of mild and severe diseases respectively. Compared with radiographic scores, the MRI scales performed better for discrimination of early osteoarticular changes.
Advanced resources for plant genomics: a BAC library specific for the short arm of wheat chromosome 1B
Authors: Janda Jaroslav , Šafář Jan , Kubaláková Marie , Bartoš Jan , Kovářová Pavlína , Suchánková Pavla , Pateyron Stephanie , Číhalíková Jarmila , Sourdille Pierre , Šimková Hana , Faivre‐Rampant Patricia , Hřibová Eva , Bernard Michel , Lukaszewski Adam , Doležel Jaroslav , Chalhoub Boulos
Published: August 2006

Common wheat (Triticum aestivum L., 2n = 6x = 42) is a polyploid species possessing one of the largest genomes among the cultivated crops (1C is approximately 17 000 Mb). The presence of three homoeologous genomes (A, B and D), and the prevalence of repetitive DNA make sequencing the wheat genome a daunting task. We have developed a novel ‘chromosome arm‐based’ strategy for wheat genome sequencing to simplify this task; this relies on sub‐genomic libraries of large DNA inserts. In this paper, we used a di‐telosomic line of wheat to isolate six million copies of the short arm of chromosome 1B (1BS) by flow sorting. Chromosomal DNA was partially digested with HindIII and used to construct an arm‐specific BAC library. The library consists of 65 280 clones with an average insert size of 82 kb. Almost half of the library (45%) has inserts larger than 100 kb, while 18% of the inserts range in size between 75 and 100 kb, and 37% are shorter than 75 kb. We estimated the chromosome arm coverage to be 14.5‐fold, giving a 99.9% probability of identifying a clone corresponding to any sequence on the short arm of 1B. Each chromosome arm in wheat can be flow sorted from an appropriate cytogenetic stock, and we envisage that the availability of chromosome arm‐specific BAC resources in wheat will greatly facilitate the development of ready‐to‐sequence physical maps and map‐based gene cloning.
Identification and quantification of uncultivated Proteobacteria associated with pyrene degradation in a bioreactor treating PAH‐contaminated soil
Authors: Singleton David R. , Sangaiah Ramiah , Gold Avram , Ball Louise M. , Aitken Michael D.
Published: August 2006

Uncultivated bacteria associated with the degradation of pyrene in a bioreactor treating soil contaminated with polycyclic aromatic hydrocarbons (PAH) were identified by DNA‐based stable‐isotope probing (SIP) and quantified by real‐time quantitative PCR. Most of the 16S rRNA gene sequences recovered from 13C‐enriched DNA fractions clustered phylogenetically within three separate groups of β‐ and γ‐Proteobacteria unassociated with described genera and were designated ‘Pyrene Groups 1, 2 and 3’. One recovered sequence was associated with the Sphingomonas genus. Pyrene Groups 1 and 3 were present in very low numbers in the bioreactor but represented 75% and 7%, respectively, of the sequences recovered from 16S rRNA gene clone libraries constructed from 13C‐enriched DNA. In a parallel time‐course incubation with unlabelled pyrene, there was between a 2‐ and 4‐order‐of‐magnitude increase in the abundance of 16S rRNA genes from Pyrene groups 1 and 3 and from targeted Sphingomonas spp. over a 10 day incubation. Sequences from Pyrene Group 2 were 11% of the SIP clone libraries but accounted for 14% of the total bacterial 16S rRNA genes in the bioreactor community. However, the abundance of this group did not increase significantly in response to pyrene disappearance. These data indicate that the primary pyrene degraders in the bioreactor were uncultivated, low‐abundance β‐ and γ‐Proteobacteria not previously associated with pyrene degradation.
Some Notes on the Morphology of an Aberrant Actinian (Hexacorallia, Actiniaria) Associated with the Glaucothoe of the Hermit Crab Paguropsis typica Henderson (Anomura, Paguridae)
Authors: SCHÄFER WOLFGANG , HØEG JENS T. , LÜTZEN JØRGEN
Published: August 2006

The planktonic glaucothoe of the Indo‐West Pacific hermit crab Paguropsis typica Henderson has an aberrant anthozoan polyp, identified as a nynanthean actinian, attached to the underside of its thorax. The morphology of the anemone is described. The scapus is dumb‐bell shaped and exhibits a slit‐like mouth opening oriented transverse to the animal's siphonoglyphal plane. The gonads are very well developed, whereas tentacle‐like structures or retractor muscles of certain septa are reduced. In the adult stage, Paguropsis typica is associated with the zoanthidean Epizoanthus paguropsides. It is assumed that the actinian is lost at the ecdysis leading to the first “hermit stage” and that P. typica might possibly seize a free Epizoanthus colony and adapt it to its body.
Spermatophore Transfer and Subsequent Sperm Development in a Homalorhagid Kinorhynch
Authors: BROWN ROSEMARY
Published: August 2006

The cuticular morphology and precise location of male and female gonopores and penile spines of the homalorhagid kinorhynch Kinorhynchus phyllotropis Brown & Higgins, 1983 are described and illustrated. In this species spermatozoa are transferred from male to female by a spermatophore. This is the first record of the mechanism of sperm transfer in a kinorhynch. The spermatophore is presumably extruded through the male gonopore and directed towards the female by the ductless penile spines. Spermatozoa in the spermatophore are rod‐shaped and catenulate. The spermatophore is pressed directly against the cuticular plates of the female, and usually covers the female gonopores. The spermatophore contains a mass of intertwined spermatids and spermatozoa surrounded by clear material covered with a layer of debris. Spermatozoa are found in the female lodged in the seminal receptacle tissue applied to the dorsal aspect of posterior oocytes. There the spermatozoa complete their development. Nuclei change from filiform to geniculate, and oval corpuscles surrounding the nuclei disappear, so that the spermatozoa are seen as densely‐packed, polyhedral cells. These observations conform with literature reports of aberrant spermatozoa of unknown origin seen in female Pycnophyes. The fertilization process remains unknown.
Class Seticoronaria and Phylogeny of the Phylum Priapulida
Authors: POR FRANCIS D.
Published: August 2006

The Recent class Seticoronaria (Priapulida) as represented by the genus Maccabeus is compared with the newly described Priapulida from the Middle Cambrian Burgess Shale. It is concluded that the Seticoronaria retained such plesiomorphic characters of the Cambrian Priapulida as sedentary life and food trapping tentacles, whereas the other Recent class, the Priapulomorpha, is the derived, apomorphic branch of this small phylum. The bearing of this hypothesis on an eventual phylogenetic sequence of the Metazoa is discussed.
An Anatomical Description of Eulima bilineata Alder with Remarks on and a Revision of Pyramidelloides Nevill (Mollusca, Prosobranchia, Eulimidae)
Authors: WARÉN ANDERS
Published: August 2006

The anatomy and biology of Eulima bilineata Alder is described and compared with PyramidelIoides miranda (A. Adams) and P. angusta (Hedley). All the species are parasitic on ophiuroids, have a ptenoglossate radula, an acrembolic proboscis with a pair of salivary glands close to the buccal mass and a reduced stomach with two histologically different digestive glands. The males have a well developed penis, the female a partly open or closed pallial oviduct. The central nervous system is concentrated. The sub‐ and supraoesophageal ganglia are completely integrated in the nerve ring. In Eulima, the supraoesophageal ganglion is split into two parts. Few differences were found between the species investigated, and it is concluded that Pyramidelloides should be classified in Eilimidae, not in Rissoidae where it has been placed previously.
Zum Nachweis des Axialkomplexes bei Holothurien (Echinodermata)
Authors: ERBER WILHELM
Published: August 2006

On the basis of a histological investigation concerning 16 species of 4 holothurian orders, the homology of the so‐called problematic canal with the axial sinus on the one side and the dorso‐axial haemal strand with the axial gland on the other side is discussed. Combining these results with former investigations, the following conclusions are drawn. There is no axial complex as an organic unit represented within the class Holothuroidea. Nevertheless, this axial complex, formerly thought to be missing, is locally disintegrated into two parts, which are isolated from each other within the dorsal mesentery. One part is the stone canal—protocoelampulla—the other one the axial sinus—axial gland. Within the holothurians there is a tendency towards reduction of the protocoelampulla and the axial sinus. This recently aberrant structure of the axial complex can be deduced from an echinoid “plan”.
Leptepsilonema gen. n. (Nematoda, Epsilonematidae) from Chile and the Caribbean Sea
Authors: CLASING ELENA
Published: August 2006

The new genus Leptepsilonema is erected. L. procerum sp.n from intertidal sandy beaches of the Caribbean sea and L. macrum sp.n. and L. exile sp.n. from Chile are described. Postembryonal development of L. procerum, covering the juvenile stages II‐IV, is presented. Some ecological data are added.
An Ultrastructural Study of Basommatophoran Spermatozoa (Mollusca, Gastropoda)
Authors: HEALY JOHN M.
Published: August 2006

Spermatozoa of the basommatophoran pulmonate families Ellobiidae (Ophicardelus ornatus Ferussac), Amphibolidae (Salinator fragilis Lamarck, Salinator solida von Martens), Siphonariidae (Siphonaria funiculata Reeve) and Lymnaeidae (Lymnaea lessoni (Deshayes)) were studied using transmission electron microscopy. Spermatozoa of all species, like most euthyneuran spermatozoa, possess (1) an acrosome composed of an apical vesicle and acrosomal pedestal (many differences between families), (2) a helically keeled, posteriorly invaginated nucleus, (3) a midpiece composed of paracrystalline and matrix materials and a variable number of incorporated glycogen‐filled helices (one in Salinator and Siphonaria, two or three in Lymnaea, three in Ophicardelus) and (4) an axoneme associated with coarse fibres (periodically banded in “neck” region) and rows of intra‐axonemal granules. The wide diversity of spermatozoon structure in the species studied, in particular the midpiece structure of Siphonaria (which resembles closely that of certain opisthobranchs) indicates that the Basommatophora may not represent a valid taxonomic unit. A comparison of basommatophoran sperm with other euthyneurans and with euspermatozoa of prosobranchs is given.
Spermatozoal Ultrastructure: Evolution and Congruence with a Holomorphological Phylogeny of the Oligochaeta (Annelida)
Authors: JAMIESON BARRIE G. M.
Published: August 2006

Plesiomorph characters for the oligochaete spermatozoon are proposed. The chief trends from these plesiomorphies have been elongation of the acrosome and its tube; withdrawal of the primary acrosome vesicle and the axial rod into the acrosome tube and development of a capitulum; development of connectives from the secondary tube to the axial rod (though there is some possibility that the reverse, absence of connectives, is plesiomorph); detorting and shortening of the midpiece (or possibly, again, the reverse) with an increase in numbers of mitochrondria from the plesiomorph four to eight; modification of the base of the tube to form a hen of variable form; and, in one line (lumbricids) flattening of the tip of the nucleus and correspondingly of the limen. Sperm ultrastructure, examined for 9 oligochaete families, corresponds well with taxonomic and phylogenetic groupings recently recognized by the author. However, convergent similarity of the phreodrilid sperm to that of the Lumbricina suggests a corresponding alteration of fertilization biology in the phreodrilids. The results indicate that the Haplotaxidae lie at the base of the opisthopores, though they do not unequivocally contraindicate acceptance of a Haplotaxis‐like form as a stem form of the Haplotaxida (opisthopores and Haplotaxidae) and Tubificida. An even more basal position for prosopores, now represented by the Lumbriculida, cannot yet be dismissed.
Sphaeromatid lsopods (Crustacea) from Brackish Waters in Queensland, Australia
Authors: HOLDICH D. M. , HARRISON K.
Published: August 2006

Exosphaeroides fluvialis gen. et sp.n. is recorded from a number of estuaries along the mainland coast of Queensland and Cymodetta gracilipes sp.n. is recorded from sediment amongst mangroves and in a ‘dry’ location on Lizard Island, in the Great Barrier Reef. The brackish water species Cymodetta gambosa Bowman & Kühne is redescribed and the genus is transferred from the hemibranchiate to the platybranchiate group of Sphaeromatidae. Another brackish water sphaeromatid, Exosphaeroma alatum Baker, is also redescribed and is removed from the hemibranchiate Sphaeromatidae to form the type‐species of a eubranchiate genus, Ptyosphaera gen.n. Details are given of the occurrence of sphaeromatid isopods in brackish water in Australia. Sphaeroma triste Heller, a wood‐boring sphaeromatid, is reported from Australia for the first time. A discussion is given concerning the colonization of brackish water and freshwater by sphaeromatids throughout the world.
A Redescription of Rhabdalestes tangensis (Lönnberg) (Pisces, Characidae) from East Africa
Authors: BAILEY ROLAND G.
Published: August 2006

Rhabdalestes tangensis (Lönnberg, 1907), a small African characin, is redescribed on the basis of new material from the Pangani River Basin in northern Tanzania. The morphometric and meristic variations described encompass those of R. leleupi Poll, 1967.
What is Tubifex tubifex (O. F. Müller) (Oligochaeta, Tubificidae)?
Authors: HOLMQUIST CHARLOTTE
Published: August 2006

A review of the fairly muddled conditions in the early history of Tubifex tubifex (O. F. Müller, 1774) is given. The identity of Müller's (1774) Lumbricus tubifex is discussed, analytical examinations of samples from the most likely type‐locality of the species are accounted for, and a neo type has been selected. For comparison, other “Tubifex” specimens, both European and American, are likewise analysed and a scrutiny of the literature concerning the species and its synonyms is undertaken. The survey results in a clearer picture of T. tubifex and a revised view of the qualifying characters on the specific level. Diagnoses of the species T. tubifex (O. F. Müller) and T. fissidens sp.n., Kernall, MS, 1914, are given.