bluuebunny/crossref_metadata_2025 huggingface dataset:
Paths to Compliance: Enforcement, Management, and the European Union
Authors: Tallberg Jonas
Published: October 2002

The contemporary debate on compliance has been framed in terms of two contending perspectives on how best to make states comply with international rules: enforcement or management. Whereas enforcement theorists stress a coercive strategy of monitoring and sanctions, management theorists embrace a problem-solving approach based on capacity building, rule interpretation, and transparency. In this article, I challenge the conception that enforcement and management are competing strategies for achieving compliance. Based on the case of the European Union (EU) and a comparison with other international regimes, I suggest that enforcement and management mechanisms are most effective when combined. The twinning of cooperative and coercive instruments in a “management-enforcement ladder” makes the EU highly successful in combating violations, thus reducing non-compliance to a temporal phenomenon. An examination of regimes in the areas of trade, environment, and human rights lends additional support to this proposition; compliance systems that offer both forms of mechanism are particularly effective in securing rule conformance, whereas systems that only rely on one of the strategies suffer in identifiable ways.
Growing Semi-Living Sculptures: The Tissue Culture & Art Project
Authors: Catts Oron , Zurr Ionat
Published: October 2002

Tissue engineering promises to replace and repair body organs but has largely been overlooked for artistic purposes. In the last 6 years, the authors have grown tissue sculptures, “semi-living objects,” by culturing cells on artificial scaffolds. The goal of this work is to culture and sustain for long periods tissue constructs of varying geometrical complexity and size, and by that process to create a new artistic palette to focus attention on and challenge perceptions regarding the utilization of new biological knowledge.
The Scientific and Philosophical Scope of Artificial Life
Authors: Bedau Mark
Published: October 2002

The new interdisciplinary science of ALife has had a connection with the arts from its inception. This paper provides an overview of ALife, reviews its key scientific challenges and discusses its philosophical implications. It ends with a few words about the implications of ALife for the arts.
On Minimalist Approaches to the Locality of Movement
Authors: Fitzpatrick Justin M.
Published: October 2002

Several distinct approaches to the locality of movement have emerged within the Minimalist Program, but little attention has been paid to their formal and empirical differences. I examine a range of possible locality constraints on movement that are representative of current approaches. I expose some important formal differences among these alternatives and examine five phenomena, some previously unnoted, that distinguish them empirically. No single approach succeeds in capturing all of the facts that should arguably follow from a theory of locality, but the bulk of the evidence seems to support a theory that defines locality using only simple and independently motivated syntactic objects and relations.
Scalable Hybrid Computation with Spikes
Authors: Sarpeshkar Rahul , O'Halloran Micah
Published: October 2002

We outline a hybrid analog-digital scheme for computing with three important features that enable it to scale to systems of large complexity: First, like digital computation, which uses several one-bit precise logical units to collectively compute a precise answer to a computation, the hybrid scheme uses several moderate-precision analog units to collectively compute a precise answer to a computation. Second, frequent discrete signal restoration of the analog information prevents analog noise and offset from degrading the computation. And, third, a state machine enables complex computations to be created using a sequence of elementary computations. A natural choice for implementing this hybrid scheme is one based on spikes because spike-count codes are digital, while spike-time codes are analog. We illustrate how spikes afford easy ways to implement all three components of scalable hybrid computation. First, as an important example of distributed analog computation, we show how spikes can create a distributed modular representation of an analog number by implementing digital carry interactions between spiking analog neurons. Second, we show how signal restoration may be performed by recursive spike-count quantization of spike-time codes. And, third, we use spikes from an analog dynamical system to trigger state transitions in a digital dynamical system, which reconfigures the analog dynamical system using a binary control vector; such feedback interactions between analog and digital dynamical systems create a hybrid state machine (HSM). The HSM extends and expands the concept of a digital finite-state-machine to the hybrid domain. We present experimental data from a two-neuron HSM on a chip that implements error-correcting analog-to-digital conversion with the concurrent use of spike-time and spike-count codes. We also present experimental data from silicon circuits that implement HSM-based pattern recognition using spike-time synchrony. We outline how HSMs may be used to perform learning, vector quantization, spike pattern recognition and generation, and how they may be reconfigured.
Center-Crossing Recurrent Neural Networks for the Evolution of Rhythmic Behavior
Authors: Mathayomchan Boonyanit , Beer Randall D.
Published: October 2002

A center-crossing recurrent neural network is one in which the null- (hyper) surfaces of each neuron intersect at their exact centers of symmetry, ensuring that each neuron's activation function is centered over the range of net inputs that it receives. We demonstrate that relative to a random initial population, seeding the initial population of an evolutionary search with center-crossing networks significantly improves both the frequency and the speed with which high-fitness oscillatory circuits evolve on a simple walking task. The improvement is especially striking at low mutation variances. Our results suggest that seeding with center-crossing networks may often be beneficial, since a wider range of dynamics is more likely to be easily accessible from a population of center-crossing networks than from a population of random networks.
Computational Capacity of an Odorant Discriminator: The Linear Separability of Curves
Authors: Caticha N. , Tejada J. E. Palo , Lancet D. , Domany E.
Published: October 2002

We introduce and study an artificial neural network inspired by the probabilistic receptor affinity distribution model of olfaction. Our system consists of N sensory neurons whose outputs converge on a single processing linear threshold element. The system's aim is to model discrimination of a single target odorant from a large number p of background odorants within a range of odorant concentrations. We show that this is possible provided p does not exceed a critical value pc and calculate the critical capacity αc = pc/N. The critical capacity depends on the range of concentrations in which the discrimination is to be accomplished. If the olfactory bulb may be thought of as a collection of such processing elements, each responsible for the discrimination of a single odorant, our study provides a quantitative analysis of the potential computational properties of the olfactory bulb. The mathematical formulation of the problem we consider is one of determining the capacity for linear separability of continuous curves, embedded in a large-dimensional space. This is accomplished here by a numerical study, using a method that signals whether the discrimination task is realizable, together with a finite-size scaling analysis.
On the Emergence of Rules in Neural Networks
Authors: Hanson Stephen José , Negishi Michiro
Published: October 2002

A simple associationist neural network learns to factor abstract rules (i.e., grammars) from sequences of arbitrary input symbols by inventing abstract representations that accommodate unseen symbol sets as well as unseen but similar grammars. The neural network is shown to have the ability to transfer grammatical knowledge to both new symbol vocabularies and new grammars. Analysis of the state-space shows that the network learns generalized abstract structures of the input and is not simply memorizing the input strings. These representations are context sensitive, hierarchical, and based on the state variable of the finite-state machines that the neural network has learned. Generalization to new symbol sets or grammars arises from the spatial nature of the internal representations used by the network, allowing new symbol sets to be encoded close to symbol sets that have already been learned in the hidden unit space of the network. The results are counter to the arguments that learning algorithms based on weight adaptation after each exemplar presentation (such as the long term potentiation found in the mammalian nervous system) cannot in principle extract symbolic knowledge from positive examples as prescribed by prevailing human linguistic theory and evolutionary psychology.
Sufficient Conditions for Error Backflow Convergence in Dynamical Recurrent Neural Networks
Authors: Aussem Alex
Published: October 2002

This article extends previous analysis of the gradient decay to a class of discrete-time fully recurrent networks, called dynamical recurrent neural networks, obtained by modeling synapses as finite impulse response (FIR) filters instead of multiplicative scalars. Using elementary matrix manipulations, we provide an upper bound on the norm of the weight matrix, ensuring that the gradient vector, when propagated in a reverse manner in time through the error-propagation network, decays exponentially to zero. This bound applies to all recurrent FIR architecture proposals, as well as fixed-point recurrent networks, regardless of delay and connectivity. In addition, we show that the computational overhead of the learning algorithm can be reduced drastically by taking advantage of the exponential decay of the gradient.
Electoral Guerrilla Theatre in Australia: Pauline Hanson vs. Pauline Pantsdown
Authors: Bogad Lawrence M.
Published: October 2002

Parody can be a potent political weapon—as demonstrated in the creation of “Pauline Pantsdown”, the in-your-face drag version of Pauline Hanson, the far-right founder of Australia's One Nation Party. Did Pantsdown bring Hanson down?
Ike and Italy: The Eisenhower Administration and Italy's “Neo-Atlanticist” Agenda
Authors: Brogi Alessandro
Published: October 2002

U.S. -Italian relations in the 1950s were shaped in part by Italy's pursuit of a “Neo-Atlanticist” policy—a policy that emphasized economic multilateralism within the Western alliance and active diplomatic engagement with the nonaligned Arab countries. The Neo-Atlanticist approach led to certain ac-complishments but also to some notable failures. By late 1959, when domes-tic political squabbles and an unpropitious international climate brought an end to the Neo-Atlanticist policy, Italy had been unable to attain its chief objective of a significant increase in its international standing. The country did, however, shift from being a mere client of the United States to something closer to a full-fledged partner. Despite the failures of Neo-Atlanticism, the policy showed that a reliance on “soft power” (non-coercive means of influence)can work in some circumstances.
Capital Controls in Malaysia: Effectiveness and Side Effects
Authors: Cook David , Devereux Michael B.
Published: October 2002

In 1998 and 1999, following the East Asian financial crisis, Malaysia imposed a set of constraints and taxes on the movement of capital out of the country. Using a quantitative equilibrium model, we attempt to construct estimates of the effects of these controls on Malaysia's recovery from the crisis. The analysis relies on a model of a dependent economy with taxation on capital movements. We focus on the aftermath of a financial panic (the East Asian crisis) in which effective international interest rates rise. Capital taxation implicitly ameliorates the brunt of such a rise in the interest rate and substantially limits its real effects. This amelioration is shown to be especially significant under fixed exchange rates.
The Samson Story as Border Fiction
Authors: Weitzman Steve
Published: October 2002

This essay explores the role of story-telling in constructing Judah's border with the Philistines in the shephelah. Judah's struggle to control this frontier involved overcoming social pressures and incentives that naturally pulled Israelites and Philistines living in it toward integration and hybridization. The Samson story, the most famous biblical narrative associated with the shephelah, offers us an opportunity to reconstruct a possible role for story-telling in counteracting this pressure. Drawing on parallels with Greek myth, I argue that the Samson narrative does not merely reflect the ethnic and cultural ambiguities of the shephelah but seeks to assert control over them, doing so in ways that delegitimize Philistine claims to this region and stigmatize border-crossing. What we have in the Samson story, in other words, is an attempt to impose a fictional border between Judah and the Philistines in the shephelah, a border no less inhibitive for being imaginary.
"TO MIX OR NOT TO MIX": SYNCRETISM/ANTI-SYNCRETISM IN THE HISTORY OF THEOSOPHY
Authors: Kraft Siv Ellen
Published: October 2002

Once defined as a "mishmash of religions," syncretism has been referred to as a meaningless, derogatory and essentialistic term which should be banned from the fields of religio-historical research. Written in defence of the category, this article provides a review of problematic aspects and recent attempts to deal with them. Particularly useful in this concern, anthropologists Rosalind Shaw and Charles Stewart have suggested a demarcation between "syncretism" (as the politics of religious synthesis) and "anti-syncretism" (as attempts to protect religious boundaries). Taking their tools as a starting point, this article discusses shifting tendencies in the history of Theosophy. The Theosophical Society started out, it is argued, as a hyper-syncretistic religion, while at the same time promoting anti-syncretism on behalf of other religions. More recently, these strategies have been replaced by efforts to protect boundaries and demarcate its Blavatskian roots.
On Modeling Cognition and Culture: Why cultural evolution does not require replication of representations
Authors: Henrich Joseph , Boyd Robert
Published: October 2002

Formal models of cultural evolution analyze how cognitive processes combine with social interaction to generate the distributions and dynamics of 'representations.' Recently, cognitive anthropologists have criticized such models. They make three points: mental representations are non-discrete, cultural transmission is highly inaccurate, and mental representations are not replicated, but rather are 'reconstructed' through an inferential process that is strongly affected by cognitive 'attractors.' They argue that it follows from these three claims that: 1) models that assume replication or replicators are inappropriate, 2) selective cultural learning cannot account for stable traditions, and 3) selective cultural learning cannot generate cumulative adaptation. Here we use three formal models to show that even if the premises of this critique are correct, the deductions that have been drawn from them are false. In the first model, we assume continuously varying representations under the influence of weak selective transmission and strong attractors. We show that if the attractors are sufficiently strong relative to selective forces, the continuous representation model reduces to the standard discrete-trait replicator model, and the weak selective component determines the final equilibrium of the system. In the second model, we assume inaccurate replication and discrete traits. We show that very low fidelity replication of representations at the individual level does not preclude accurate replication at the population level, and therefore, accurate individual-level replication of representations is not necessary for either cultural inertia or cumulative cultural adaptation. In the third model, we derive plausible conditions for cumulative adaptive evolution, assuming continuous cultural representations, incomplete transmission and substantial inferential transformations.
Testosterone versus psychological castration in the expression of dominance, territoriality and breeding behavior by male village weavers (Ploceus cucullatus)
Authors: Collias Nicholas , Barfield Ronald , Tarvyd Edward
Published: October 2002

The village weaver (Ploceus cucullatus), a tropical passerine bird widely distributed in subSaharan Africa, was the subject of experiments in aviaries at our university. Castrated males fall in the dominance hierarchy, fewer such males establish territorial ownership, they sing less often and weave fewer nests. Injection with testosterone propionate in castrates, or in normal males outside the breeding season, tends to stimulate aggressiveness and breeding behavior. However, the most dominant individuals may strongly suppress breeding behavior by subordinate males (psychological castration). Thus, outside the breeding season, subordinate males that were injected with testosterone propionate to which they at first showed little response, promptly began to sing or sang significantly much more often, and established territories, after dominant males were removed from their aviary.
Do kentish plovers regulate the amount of their nest material? an experimental test
Authors: Szentirmai István , Székely Tamás
Published: October 2002

Parent birds are often assumed to regulate the amount of their nest material during incubation in response to various costs and benefits. This assumption, however, is rarely tested. We investigated this assumption in a ground-nesting shorebird, the Kentish plover (Charadrius alexandrinus) by experimentally manipulating the amount of nest material. Materials were removed from some nests (reduced nests) and added to other nests (increased nests), whereas in control nests the amount of nest material was not manipulated. In both reduced and increased nests the parents restored the original amount of nest material within 24 hours. The parents tended to spend more time on arranging nest material in both reduced and increased nests than in control nests. However, neither incubation behaviour nor internal egg temperatures were different between reduced, increased and control nests. We conclude that Kentish plovers can quickly adjust the amount of materials around their eggs. This suggests that the parents carefully balance the various costs and benefits of nest material use during incubation.
Nematodes of the order Dorylaimida from Andalucía Oriental, Spain: Discolaimus Cobb, 1913. 1. Description of two new species
Authors: Torres Baltasar , Abolafia Joaquín , Peña-Santiago Reyes , Liébanas Gracia
Published: October 2002

Two new species of the genus Discolaimus Cobb, 1913 are described from southeastern Spain. D. mariae sp. n. is distinguished by its large size (L = 2.4-3.3 mm), lip region diameter 29-35 μm, odontostyle 23-25 μm, pharyngeal expansion occupying two-thirds of the total neck length, presence of dorsal cell bodies close to cardia, V = 46-53, female genital system didelphicamphidelphic, tail conical with rounded terminus (33-39 μm, c = 72-88, c′ = 0.9-1.0) and with a terminal gap in the inner cuticle, and males absent. D. labiatus sp. n. is characterised by being medium sized (L = 0.99-1.20 mm), lip region diameter 14-17 μm wide, labial disc with no radial but six longitudinal grooves, inner (perioral) labial portion forming well developed liplets, odontostyle 10.0-12.5 μm, vulva relatively anterior (V = 39-43), female tail conical with rounded terminus (26-27 μm, c = 37-46, c′ = 1.5-1.7), and male unknown. Scanning electron microscope observations of the species are also presented.
The discursive position of religious studies in Japan: Masaharu Anesaki and the origins of religious studies
Authors: Isomae Jun'ichi
Published: October 2002

In Japan today, the issue of religious cults is a frequent topic of discussion, particularly in the aftermath of the Aum Shinrikyo incident. However, at the time of the Aum incident, the views of scholars in religious studies were scarcely heeded. This can be attributed to the fact that for many people, religious studies was thought to lean too much toward a defense of religion. Focusing upon Masaharu Anesaki, the founder of religious studies in Japan, this article explores the fundamental characteristics of the discourse of religious studies as it has come down to the present day. It seeks to elucidate the close relationship of religious studies to the political situation in Japanese society during the Meiji period (1868-1912), and how this contributed to the development of the field. It further maintains that in conjunction with state policies for national education, the discourse of religious studies helped instantiate religion as an integral component of modern society, one defined particularly by the vacillation between individualism and nationalism. After World War II, there were few in Japan who would openly express admiration for nationalist ideology, but in religious studies a tendency toward nationalism remained evident in its yearning for the solidarity of religious groups and other kinds of communal bodies. Thus, even as its outward form underwent change, this tendency toward nationalism not only served as a defense of religion, but it also continued to uphold the existing discursive positionality of religious studies.
Characterization and crystal chemistry of an Fe-rich montmorillonite from Ölberg, Germany
Authors: Petit S. , Caillaud J . , Righi D. , Madejová J . , Elsass F. , Köster H. M.
Published: October 2002

An Fe-rich smectite from Ölberg (Germany) was characterized using X-ray diffraction, infrared spectroscopy and analytical electron microscopy. Progressive reduction of the octahedral charge was performed through the Hofmann & Klemen effect at increasing temperatures. The sample was heterogeneous, consisting of two smectite populations. One population, which comprises a minor portion of the sample, is an ‘Fe3+-montmorillonite’ with little or no tetrahedral charge and Fe3+as the major octahedral cation. The other population, a major constituent of the sample, contains less Mg and more Al than the first one and exhibits some tetrahedral charge. This fraction may be considered as an inter-grade between nontronite (dominant tetrahedral charge) and Fe3+-montmorillonite (dominant octahedral charge). These two populations may occur as separate particles but also as interstratified layers.
Short-term granulocyte colony-stimulating factor and erythropoietin treatment enhances hematopoiesis and survival in the mitomycin C–conditioned Fancc−/− mouse model, while long-term treatment is ineffective
Authors: Carreau Madeleine , Liu Lili , Gan Olga I. , Hitzler Johann K. , Dick John E. , Buchwald Manuel
Published: October 2002

Transient treatment with cytokines appears to improve hematopoietic function in Fanconi anemia; however, the effectiveness or adverse effect of long-term treatment is not known. The mitomycin C–treatedFancc−/− mouse provides a valuable model to address long-term efficacy of such treatment.Fancc−/− mice injected with granulocyte colony-stimulating factor, erythropoietin, or both cytokines showed a delay in mitomycin C (MMC)–induced bone marrow (BM) failure compared to untreated mice. However, long-term cytokine exposure followed by MMC challenges did not protect mice from the reduction of peripheral blood counts or the number of early myeloid progenitors. These results suggest that cytokine treatment may be beneficial only in the short-term, while long-term treatment is not protective for BM aplasia.
Functionally distinct dendritic cell (DC) populations induced by physiologic stimuli: prostaglandin E2 regulates the migratory capacity of specific DC subsets
Authors: Luft Thomas , Jefford Michael , Luetjens Petra , Toy Tracey , Hochrein Hubertus , Masterman Kelly-Anne , Maliszewski Charlie , Shortman Ken , Cebon Jonathan , Maraskovsky Eugene
Published: October 2002

Migration of antigen (Ag)-loaded dendritic cells (DCs) from sites of infection into draining lymphoid tissues is fundamental to the priming of T-cell immune responses. We evaluated monocyte-derived DCs (MoDCs) and peripheral blood DCs (PBDCs) to respond to proinflammatory mediators, CD40L, and intact bacteria. All classes of stimuli induced DC phenotypic maturation. However, for MoDCs, only prostaglandin E2 (PGE2)–containing stimuli induced migratory-type DCs. Thus, immature MoDCs that encountered proinflammatory cytokines or CD40L or intact bacteria in the presence of PGE2 acquired migratory capacity but secreted low levels of cytokines. Conversely, MoDCs that encountered pathogens or CD40L alone become nonmigratory cytokine-secreting cells (proinflammatory type). Interestingly, both migratory- and proinflammatory-type DCs expressed equivalent levels of chemokine receptors, suggesting that the role of PGE2 was to switch on migratory function. We demonstrate that PGE2 induces migration via the E-prostanoid 2/E-prostanoid 4 (EP2/EP4) receptors and the cAMP pathway. Finally, migratory-type MoDCs stimulated T-cell proliferation and predominantly IL-2 secretion, whereas proinflammatory-type MoDCs induced IFN-γ production. In contrast, CD1b/c+ PBDC rapidly acquired migratory capacity irrespective of the class of stimulus encountered and secreted low levels of cytokines. This suggests that not all mature stages of DCs are destined to migrate to lymphoid organs and that the sequence in which stimuli are encountered significantly affects which functions are expressed. Thus, certain immature DC subsets recruited from the resting precursor pool may have multiple functional fates that play distinct roles during the induction and effector phases of the immune response. These findings have important implications for the clinical utility of DCs in immunotherapy.
Living T9 glioma cells expressing membrane macrophage colony-stimulating factor produce immediate tumor destruction by polymorphonuclear leukocytes and macrophages via a “paraptosis”-induced pathway that promotes systemic immunity against intracranial T9 gliomas
Authors: Chen Yijun , Douglass Thomas , Jeffes Edward W. B. , Xu Qingcheng , Williams Christopher C. , Arpajirakul Neary , Delgado Christina , Kleinman Michael , Sanchez Ramon , Dan Qinghong , Kim Ronald C. , Wepsic H. Terry , Jadus Martin R.
Published: October 2002

Cloned T9-C2 glioma cells transfected with membrane macrophage colony-stimulating factor (mM-CSF) never formed subcutaneous tumors when implanted into Fischer rats, whereas control T9 cells did. The T9-C2 cells were completely killed within 1 day through a mechanism that resembled paraptosis. Vacuolization of the T9-C2 cell's mitochondria and endoplasmic reticulum started within 4 hours after implantation. By 24 hours, the dead tumor cells were swollen and terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL)–positive. Bcl2-transduced T9-C2 cells failed to form tumors in rats. Both T9 and T9-C2 cells produced cytokine-induced neutrophil chemoattractant that recruited the granulocytes into the tumor injection sites, where they interacted with the tumor cells. Freshly isolated macrophages killed the T9-C2 cells in vitro by a mechanism independent of phagocytosis. Nude athymic rats treated with antiasialo GM1 antibody formed T9-C2 tumors, whereas rats treated with a natural killer cell (NK)–specific antibody failed to form tumors. When treated with antipolymorphonuclear leukocyte (anti-PMN) and antimacrophage antibodies, 80% of nude rats formed tumors, whereas only 40% of the rats developed a tumor when a single antibody was used. This suggests that both PMNs and macrophages are involved in the killing of T9-C2 tumor cells. Immunocompetent rats that rejected the living T9-C2 cells were immune to the intracranial rechallenge with T9 cells. No vaccinating effect occurred if the T9-C2 cells were freeze-thawed, x-irradiated, or treated with mitomycin-C prior to injection. Optimal tumor immunization using mM-CSF–transduced T9 cells requires viable tumor cells. In this study optimal tumor immunization occurred when a strong inflammatory response at the injection of the tumor cells was induced.
Reconstitution of lymphoid development and function in ZAP-70–deficient mice following gene transfer into bone marrow cells
Authors: Otsu Makoto , Steinberg Marcos , Ferrand Christophe , Merida Peggy , Rebouissou Cosette , Tiberghien Pierre , Taylor Naomi , Candotti Fabio , Noraz Nelly
Published: October 2002

Mutations in the ZAP-70 protein tyrosine kinase gene result in a severe combined immunodeficiency (SCID) characterized by a selective inability to produce CD8+ T cells and a signal transduction defect in peripheral CD4+ cells. Transplantation of genetically modified hematopoietic progenitor cells that express the wild-type ZAP-70 gene may provide significant benefit to some of these infants. The feasibility of stem cell gene correction for human ZAP-70 deficiency was assessed using a ZAP-70 knock-out model. ZAP-70–deficient murine bone marrow progenitor cells were transduced with a retroviral vector expressing the human ZAP-70 gene. Engraftment of these cells in irradiated ZAP-70–deficient animals resulted in the development of mature CD4+ and CD8+ T cells. In marked contrast, both populations were absent in ZAP-70−/− mice undergoing transplantation with bone marrow progenitor cells transduced with a control vector. Importantly, ZAP-70–reconstituted T cells proliferated in response to T-cell receptor stimulation. Moreover, these ZAP-70–expressing T cells demonstrated a diverse T-cell receptor repertoire as monitored by the relative usage of each T-cell receptor β chain hypervariable region subfamily. The presence of ZAP-70 in B cells did not affect either lipopolysaccharide- or lipopolysaccharide/interleukin-4–mediated immunoglobulin isotype switching. Altogether, these data indicate that retroviral-mediated gene transfer of the ZAP-70 gene may prove to have a therapeutic benefit for patients with ZAP-70–SCID.
Expression of a human β-globin transgene in erythroid cells derived from retrovirally transduced transplantable human fetal liver and cord blood cells
Authors: Nicolini Franck E. , Imren Suzan , Oh Il-Hoan , Humphries R. Keith , Leboulch Philippe , Fabry Mary E. , Nagel Ronald L. , Eaves Connie J.
Published: October 2002

Transfer of therapeutic genes to human hematopoietic stem cells (HSCs) using complex vectors at clinically relevant efficiencies remains a major challenge. Recently we described a stable retroviral vector that sustains long-term expression of green fluorescent protein (GFP) and a human β-globin gene in the erythroid progeny of transduced murine HSCs. We now report the efficient transduction of primitive human CD34+ fetal liver or cord blood cells with this vector and expression of the β-globin transgene in the erythroid progeny of these human cells for at least 2 months. After growth factor prestimulation and then a 2- to 3-day exposure to the virus, 35% to 55% GFP+ progeny were seen in assays of transduced colony-forming cells, primitive erythroid precursors that generate large numbers of glycophorin A+ cells in 3-week suspension cultures, and 6-week long-term culture-initiating cells. In immunodeficient mice injected with unselected infected cells, 5% to 15% of the human cells regenerated in the marrow (including the erythroid cells) were GFP+ 3 and 6 weeks after transplantation. Importantly, the numbers of GFP+ human lymphoid and either granulopoietic or erythroid cells in individual mice 6 weeks after transplantation were significantly correlated, indicative of the initial transduction of human multipotent cells with in vivo repopulating activity. Expression of the transduced β-globin gene in human cells obtained directly from the mice or after their differentiation into erythroid cells in vitro was demonstrated by reverse transcriptase–polymerase chain reaction using specific primers. These experiments represent a significant step toward the realization of a gene therapy approach for human β-globin gene disorders.
Factor VIII expression in azoxymethane-induced murine fulminant hepatic failure
Authors: Doering Christopher B. , Josephson Cassandra D. , Craddock Heather N. , Lollar Pete
Published: October 2002

Fulminant hepatic failure (FHF) in humans produces a bleeding diathesis due in large part to a reduction in the biosynthesis of liver-derived coagulation factors. Remarkably, factor VIII procoagulant activity is elevated in most of these patients despite widespread liver cell death. FHF can be modeled in mice by administration of azoxymethane, the active ingredient found in cycad palm nuts. We compared the expression of factor VIII to other hepatic hemostatic factors in azoxymethane-induced murine FHF. Mice displayed dose-dependent decreases in all coagulation factor activities measured, including factors V, VII, VIII, and IX. At the highest dose of azoxymethane (50 μg/g body weight), factor VIII activity in plasma decreased by 98% within 36 hours after treatment, which was associated with an 80% reduction in hepatic factor VIII messenger RNA (mRNA). In contrast, factor VIII mRNA levels in spleen, kidney, and lung tissue of azoxymethane-treated mice were unchanged. Cellular damage in these mice appeared to be limited to hepatocytes as evident by histologic examination. This finding is supported by 2 observations. First, hepatic mRNA levels of von Willebrand factor, which is synthesized by liver sinusoidal endothelial cells but not hepatocytes, were unchanged. Second, von Willebrand factor was detected antigenically in liver sections of azoxymethane-treated mice by immunofluorescence. These results indicate that the contribution of the liver to factor VIII biosynthesis is not replaced or significantly supplemented by other tissues in this model of FHF.
Circulating and binding characteristics of wild-type factor IX and certain Gla domain mutants in vivo
Authors: Gui Tong , Lin Hui-Feng , Jin Da-Yun , Hoffman Maureane , Straight David L. , Roberts Harold R. , Stafford Darrel W.
Published: October 2002

Residue K5 in factor IX γ-carboxyglutamic acid (Gla) domain participates in binding endothelial cells/collagen IV. We injected recombinant factor IX containing mutations at residue 5 (K5A, K5R) into factor IX–deficient mice and compared their behavior with that of wild-type factor IX. The plasma concentration of factor IX that binds to endothelial cells/collagen IV (recombinant wild type and K5R) was consistently lower than that of the one that does not bind (K5A). Mice treated with wild type or K5R had 79% of the injected factor IX in the liver after 2 minutes, whereas 17% remained in circulation. In mice injected with K5A, 59% of the injected factor IX was found in liver and 31% was found in plasma. When we blocked the liver circulation before factor IX injection, 74% of K5A and 64% of K5R remained in the blood. When we treated the mouse with EDTA after injecting exogenous factor IX, the blood levels of factor IX that bind to endothelial cells/collagen IV increased, presumably because of release from endothelial cell/collagen IV binding sites. In contrast, the levels of the mutants that do not bind were unaffected by EDTA. In immunohistochemical studies, factor IX appears on the endothelial surfaces of mouse arteries after factor IX injection and of human arteries from surgical specimens. Thus, we have demonstrated that factor IX binds in vivo to endothelial cell–collagen IV surfaces. Our results suggest that factor IX Gla-domain mediated binding to endothelial cells/collagen IV plays a role in controlling factor IX concentration in the blood.
Band 3 is an anchor protein and a target for SHP-2 tyrosine phosphatase in human erythrocytes
Authors: Bordin Luciana , Brunati Anna Maria , Donella-Deana Arianna , Baggio Bruno , Toninello Antonio , Clari Giulio
Published: October 2002

Tyr phosphorylation of the multifunctional transmembrane protein band 3 has been implicated in several erythrocyte functions and disorders. We previously demonstrated that pervanadate treatment of human erythrocytes induces band-3 Tyr phosphorylation, which is catalyzed by the sequential action of tyrosine kinase Syk and tyrosine kinase(s) belonging to the Src family. In this study, we show that Tyr phosphorylation of band 3, elicited by pervanadate, N-ethylmaleimide, or diamide, greatly increases band-3 interaction with the tyrosine phosphatase SHP-2 in parallel with the translocation of SHP-2 to erythrocyte membranes. These events seem to be mediated by Src-like catalyzed phosphorylation of band 3 because both SHP-2 translocation to cellular membranes and its interaction with Tyr-phosphorylated protein are greatly counteracted by PP2, a specific inhibitor of Src kinases. Binding-competition experiments demonstrate that SHP-2 recruitment to band 3 occurs via its SH2 domain(s). In particular, our data support the view that SHP-2 docks specifically with P-Y359 of band 3. Experiments performed with intact erythrocytes in the presence of the SHP-2 inhibitor calpeptin suggest that, once recruited to Tyr-phosphorylated band 3, the tyrosine phosphatase dephosphorylates the protein. P-Y8, 21, and 904 are the residues affected by SHP-2, as judged by 32P-peptide mapping of band 3 digested with trypsin. These results indicate that in treated erythrocytes, recruitment of cytosolic SHP-2 to band 3 is a prerequisite for the subsequent dephosphorylation of the transmembrane protein.
High numbers of active caspase 3–positive Reed-Sternberg cells in pretreatment biopsy specimens of patients with Hodgkin disease predict favorable clinical outcome
Authors: Dukers Danny F. , Meijer Chris J. L. M. , ten Berge Rosita L. , Vos Wim , Ossenkoppele Gert J. , Oudejans Joost J.
Published: October 2002

In vitro studies suggest that resistance to the apoptosis-inducing effect of chemotherapy might explain poor responses to therapy in fatal instances of Hodgkin disease (HD). Execution of apoptosis depends on proper functioning of effector caspases, in particular caspase 3, which is activated on the induction of apoptosis through either the stress-induced pathway or the death receptor–mediated pathway. Thus, high levels of caspase 3 activation should reflect proper functioning of one or both identified apoptosis pathways, resulting in chemotherapy-sensitive neoplastic cells and thus a favorable clinical response to chemotherapy. We tested this hypothesis by quantifying active caspase 3–positive tumor cells in primary biopsy specimens of HD and compared these numbers to clinical outcomes. Using an immunohistochemical assay, activation of caspase 3 was detected in 0% to 13% of neoplastic cells. High numbers of active caspase 3–positive tumor cells (5% or more) correlated with excellent clinical prognosis; 0 of 22 patients with 5% or more active caspase 3–positive cells died compared with 11 of 41 patients with less than 5% positive cells (P = .007). Proper functioning of active caspase 3 was demonstrated by the detection of one of its cleaved substrates, PARP-1/p89, in similar percentages of neoplastic cells. High levels of active caspase 3–positive neoplastic cells were associated with the expression of p53 and its downstream effector molecule p21, suggesting proper functioning of the stress-induced apoptosis pathway. In conclusion, high numbers of active caspase 3–positive neoplastic cells predict a highly favorable clinical outcome in HD patients, supporting the notion that an (at least partially) intact apoptosis cascade is essential for the cell killing effect of chemotherapy.
Persistence of HTLV-I in blood components after leukocyte depletion
Authors: Pennington Joanne , Taylor Graham P. , Sutherland Janet , Davis Ricardo E. , Seghatchian Jerhard , Allain Jean-Pierre , Williamson Lorna M.
Published: October 2002

The human T-cell leukemia virus HTLV-I is a transfusion-transmissible retrovirus targeting T lymphocytes for which screening is not currently undertaken in United Kingdom blood donors. The introduction of universal leukocyte depletion (LD) of the United Kingdom blood supply raises the question as to the degree of protection afforded by this procedure against HTLV-I transmission by blood components. HTLV-I viral DNA removal by leukocyte-depleting filters was assessed in units of whole blood and platelets by real-time quantitative polymerase chain reaction (PCR) and by nested PCR for HTLV-I Tax DNA. We examined HTLV-I removal by LD filters using a model system of blood units containing exogenous spiked HTLV-I–positive MT-2 cells at a relevant concentration and whole blood donations from asymptomatic HTLV-I carriers. T-lymphocyte removal was assessed in parallel by measurement of endogenous subset-specific CD3 mRNA. In the MT-2 model system we observed 3.5 log10 to 4 log10 removal of HTLV-I Tax DNA by filtration of whole blood and 2 log10 to 3 log10 removal across platelet filters with 13 of 16 whole blood and 8 of 8 platelet units still positive after filtration. Despite 3 log10 to 4 log10 viral removal, HTLV-I Tax DNA could be detected after whole blood filtration in asymptomatic carriers with viral loads above 108 proviral DNA copies/L. T-lymphocyte removal was also between 3.5 log10 and 4.5 log10. HTLV-I provirus removal was incomplete in the model system and in asymptomatic carriers with viral loads greater than 108 copies/L. These results suggest that LD alone may not provide complete protection from HTLV-I transmission by transfusion.
Keratinocyte growth factor preserves normal thymopoiesis and thymic microenvironment during experimental graft-versus-host disease
Authors: Rossi Simona , Blazar Bruce R. , Farrell Catherine L. , Danilenko Dimitry M. , Lacey David L. , Weinberg Kenneth I. , Krenger Werner , Holländer Georg A.
Published: October 2002

Thymus-dependent reconstitution of the peripheral T-cell compartment is critical for the successful outcome of bone marrow transplantation. However, graft-versus-host disease (GVHD) affects thymic stromal function and thus prevents normal T-cell maturation and selection. To determine whether cytoprotection of thymic epithelial cells (TECs) by keratinocyte growth factor (KGF) averts GVHD-related injury to the thymus, a nonirradiated murine parent→F1 transplantation model was investigated. Administration of KGF between days −3 and +3 of GVHD induction preserved normal thymic size, cellularity, and thymocyte phenotype when measured 2 weeks after transplantation and compared with saline-treated parent→F1 mice that received allogeneic transplants. Moreover, the characteristic GVHD-induced impairment in cell cycle progression of pro- and pre-T cells was prevented by KGF. However, the normal phenotypic and functional status of the thymus did not correlate with the higher number of GVHD-inducing mature donor T cells in thymi of KGF-treated mice. Importantly, extensive analysis of the different TEC populations within the thymic cortex and medulla revealed an almost normal stromal architecture and composition in GVHD mice treated with KGF. These observations are likely to reflect an indirect effect of KGF on thymopoiesis as KGF-receptor expression was demonstrated to be restricted to TECs. Thus, pharmacologic doses of KGF appear to exert a potent effect on TEC function, which in turn allows for normal T lymphopoiesis to occur during acute GVHD.
Novel mutation in ferroportin1 is associated with autosomal dominant hemochromatosis
Authors: Wallace Daniel F. , Pedersen Palle , Dixon Jeannette L. , Stephenson Peter , Searle Jeffrey W. , Powell Lawrie W. , Subramaniam V. Nathan
Published: October 2002

Hemochromatosis is a common disorder characterized by excess iron absorption and accumulation of iron in tissues. Usually hemochromatosis is inherited in an autosomal recessive pattern and is caused by mutations in the HFE gene. Less common non-HFE–related forms of hemochromatosis have been reported and are caused by mutations in the transferrin receptor 2 gene and in a gene localized to chromosome 1q. Autosomal dominant forms of hemochromatosis have also been described. Recently, 2 mutations in theferroportin1 gene, which encodes the iron transport protein ferroportin1, have been implicated in families with autosomal dominant hemochromatosis from the Netherlands and Italy. We report the finding of a novel mutation (V162del) in ferroportin1 in an Australian family with autosomal dominant hemochromatosis. We propose that this mutation disrupts the function of the ferroportin1 protein, leading to impaired iron homeostasis and iron overload.
Lineage-specific growth factors can compensate for stem and progenitor cell deficiencies at the postprogenitor cell level: an analysis of doubly TPO- and G-CSF receptor–deficient mice
Authors: Kaushansky Kenneth , Fox Norma , Lin Nancy L. , Liles W. Conrad
Published: October 2002

Multiple lines of evidence indicate that thrombopoietin (TPO) substantially impacts the number of hematopoietic stem cells and progenitors of all myeloid lineages. Nevertheless, tpoknock-out mice (T−) display thrombocytopenia only; blood erythroid and neutrophil levels are normal despite 60% to 85% reductions in stem and progenitor cells. The compensatory mechanism(s) for these deficiencies remains uncertain; lineage-specific cytokines such as erythropoietin or granulocyte colony-stimulating factor (G-CSF) have been postulated but never proven to be responsible. To directly test whether G-CSF can compensate for the myeloid progenitor cell reduction in the T−model of hematopoietic deficiency, T−and G-CSF–receptor knock-out(GR−) mice were crossed, and F1 animals bred to obtain doubly nullizygous mice(T−GR−). This experiment also allowed us to test the hypothesis that G-CSF contributes to the residual platelet production in T−mice. We found that T−GR−F2 mice displayed similar blood platelet levels as that seen inT−mice, indicating that G-CSF does not account for the residual megakaryopoiesis in T−mice. However, we also noted excessive perinatal mortality ofT−GR−animals, caused by infection due to a profound and significant decrease in marrow and peripheral blood neutrophils, far greater than that seen in eitherT−or GR−mice. These data indicate that in the additional absence of GR, T−mice cannot compensate for their 62% reduction in myeloid progenitors and become profoundly neutropenic, supporting the hypothesis that G-CSF can compensate for the myeloid effects of TPO deficiency by expanding the pool of cells between the granulocyte-macrophage colony-forming unit and mature neutrophil stages of granulopoiesis.