bluuebunny/crossref_metadata_2025 huggingface dataset:
Defects in homocysteine metabolism: diversity among hyperhomocyst(e)inemias
Authors: Matthews Rowena G. , Elmore C. Lee
Published: October 2007

There are now four genetic mouse models that induce hyperhomocyst(e)inemia by decreasing the activity of an enzyme involved in homocysteine metabolism: cystathionine β-synthase, methylenetetrahydrofolate reductase, methionine synthase and methionine synthase reductase. While each enzyme deficiency leads to murine hyperhomocyst(e)inemia, the accompanying metabolic profiles are significantly and often unexpectedly, different. Deficiencies in cystathionine β-synthase lead to elevated plasma methionine, while deficiencies of the remaining three enzymes lead to hypomethioninemia. The liver [S-adenosylmethionine]/[S-adenosylhomocysteine] ratio is decreased in mice lacking methylenetetrahydrofolate reductase or cystathionine β-synthase, but unexpectedly increased in mice with deficiencies in methionine synthase or methionine synthase reductase. Folate pool imbalances are observed in complete methylenetetrahydrofolate reductase deficiency, where methyltetra-hydrofolate is a minor component, and in methionine synthase reductase deficiency, where methyltetrahydrofolate is increased relative to wild-type mice. These differences illustrate the potential diversity among human patients with hyperhomocyst(e)inemia, and strengthen the argument that the pathologies associated with the dissimilar forms of the condition will require different treatments.

Clin Chem Lab Med 2007;45:1700–3.
Perspective on the efficacy analysis of the Vitamin Intervention for Stroke Prevention trial
Authors: Spence J. David
Published: October 2007

Clin Chem Lab Med 2007;45:1582–5.
Homocysteine-lowering vitamin B treatment decreases cardiovascular events in hemodialysis patients
Authors: Righetti Marco
Published: October 2007

In Italy, the mortality rate of hemodialysis patients is approximately 14% per year. Cardiovascular disease is the most important cause of morbidity and mortality in hemodialysis patients. High plasma homocysteine levels are commonly detected in these patients, but hyperhomocysteinemia and cardiovascular mortality are not always strictly correlated. The Dialysis Outcomes and Practice Pattern Study (DOPPS) showed a direct association between regular use of water-soluble vitamins and lower cardiovascular mortality. We recently performed a long-term prospective trial to study the effects of folic acid therapy on cardiovascular events in hemodialysis patients. We observed not only a lower rate of combined cardiovascular events in patients treated with folate, but also a direct correlation between hyperhomocysteinemia and cardiovascular morbidity. On the contrary, the distribution of deaths was similar in treated and untreated patients, because, almost certainly, sudden death is not always due to atherosclerotic events, and non-cardiovascular deaths, such as cachexia, septicemia and malignancy were characterized by low levels of homocysteine, which may be, in addition, a nutritional index similar to albumin and protein catabolic rate. As it is known that diabetic hemodialysis patients have a higher mortality rate, but lower homocysteine levels as compared to non-diabetic patients, we performed an equal allocation of diabetic patients in treated and untreated groups. We observed a similar homocysteine reduction rate in diabetic patients as compared to non-diabetic patients, and a trend towards a lower rate of composite cardiovascular events in treated diabetic patients as compared to untreated diabetic patients. To summarize, the strong relationship between homocysteine and nutritional, inflammatory markers may hide its association with cardiovascular disease. Homocysteine-lowering vitamin B therapy may lower cardiovascular events in dialysis patients. It is mandatory to perform large prospective trials to confirm our results.

Clin Chem Lab Med 2007;45:1586–9.
Homocysteine and asymmetric dimethylarginine (ADMA): biochemically linked but differently related to vascular disease in chronic kidney disease
Authors: van Guldener Coen , Nanayakkara Prabath W.B. , Stehouwer Coen D.A.
Published: October 2007

Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, is formed by methylation of arginine residues in proteins and released after proteolysis. In this reaction, S-adenosylmethionine is methyldonor and S-adenosylhomocysteine the demethylated product. ADMA and homocysteine are thus biochemically linked. Both plasma homocysteine and ADMA concentrations are increased in patients with renal dysfunction, probably as a result of an impairment in their metabolic, but not urinary, clearance. Hyperhomocysteinemia has been associated with an increased risk of cardiovascular disease in end-stage renal disease, especially in patients without malnutrition and inflammation. Also, plasma ADMA levels have been associated with cardiovascular disease in renal failure patients. Both homocysteine and ADMA are thought to mediate their adverse vascular effects by impairing endothelial, nitric oxide-dependent function resulting in decreased vasodilatation, increased smooth muscle cell proliferation, platelet dysfunction and increased monocyte adhesion. At the same time, it has been shown that the correlation between plasma ADMA and homocysteine is weak and that, in renal patients, the association of plasma ADMA carotid intima-media thickness, cardiovascular events and overall mortality is independent of homocysteine. This indicates that the negative vascular effects of ADMA and homocysteine have a different etiology. Treatment with folic acid substantially lowers homocysteine, but not ADMA concentration. So far, homocysteine-lowering therapy has not been very successful in decreasing cardiovascular disease. In patients with renal failure, ADMA reduction may be an interesting new goal in the prevention of cardiovascular disease.

Clin Chem Lab Med 2007;45:1683–7.
Exploring image schemas as a critical concept: Toward a critical-cognitive linguistic account of image-schematic interactions
Authors: Tseng Ming-Yu
Published: October 2007

This article aims to advance the study of “image schemas” by drawing on insights not only from cognitive linguistics but also from critical linguistics. It highlights five specific features possessed by “image schemas”: (1) their serving as a bridge between concrete, sensorimotor experience and abstract reasoning; (2) their being emergent patterns created and evoked when people engage in understanding language; (3) their function of superimposition (i. e. interactions among image schemas); (4) their insinuation of a plus-minus parameter (i. e. the tendency of the opposing parts of an image schema to be more positively or negatively valued); and (5) their static and dynamic nature. It will also briefly address how image schemas, metaphors and socio-cultural values are entwined. The critical-cognitive perspective calls for the view of “situated” image schemas in discourse. By way of illustration, I will analyze two Chinese Zen poems. The analysis will pay special attention to imageschematic patterns and their significance in the interface between discourse, cognition, and worldview.
The expressive dimension
Authors: Potts Christopher
Published: October 2007

Expressives like damn and bastard have, when uttered, an immediate and powerful impact on the context. They are performative, often destructively so. They are revealing of the perspective from which the utterance is made, and they can have a dramatic impact on how current and future utterances are perceived. This, despite the fact that speakers are invariably hard-pressed to articulate what they mean. I develop a general theory of these volatile, indispensable meanings. The theory is built around a class of expressive indices. These determine the expressive setting of the context of interpretation. Expressive morphemes act on that context, actively changing its expressive setting. The theory is multidimensional in the sense that descriptives and expressives are fundamentally different but receive a unified logical treatment.
Re-expressing judgment
Authors: Anand Pranav
Published: October 2007

Potts (this issue) claims that non-speaker-oriented expressive content may be handled by the introduction of an expressive judge to the context. Given both that expressives may express sentiments temporally and modally displaced from the utterance and that there may be multiple expressive judges per sentence, I argue that a unitary judge is insuffcient, and suggest that non-speaker-oriented expressives are more directly captured as a species of partial quotation.
Really fucking brilliant
Authors: Geurts Bart
Published: October 2007

The title of this note has a two-tiered interpretation. On the “use” level, it expresses my admiration for the ingenuity and elegance of Christopher Potts's paper, which is not diminished by the fact that I disagree with him practically across the board. On the “mention” level, my title denotes the key phrase in Potts's example (2), which will figure rather prominently in the following remarks.
Expressives, perspective and presupposition
Authors: Lasersohn Peter
Published: October 2007

I compare Potts' use of a “judge” parameter in semantic interpretation with the use of a similar parameter in Lasersohn (2005). The latter technique portrays the content of expressives as constant across speakers, while Pott's technique does not. The idea that the content of expressives is a kind of presupposition is also briefly defended, and a technical problem in the “dynamics” of Pott's formalism is pointed out.
Beyond unpluggability
Authors: Sauerland Uli
Published: October 2007

Emotional expressions like damn and bastard seem to bring out the extreme not only in the speakers who use them, but also in the linguists who try to account for them: For Potts, nothing short of a new dimension of meaning can accommodate these expressions. Potts already in earlier work (Potts, 2003) provides one interesting argument for this view: the unpluggability (or nondisplaceability) of these expressions in many cases. Regardless of the position and level of embedding that that damn bastard John occurs in in a sentence, the speaker uttering such a sentence conveys that he, the speaker, does not think all too highly of John. In the present work, Potts still tries to maintain the core of his earlier theory, but slightly retreats from his earlier position accepting examples due to Kratzer and Schlenker where unpluggability is not observed. Potts' interesting work raises two related questions from my perspective: 1) What is the best account for the unpluggability of expressive content? and 2) Is expressive content a uniform phenomenon?
I like that damn paper – Three comments on Christopher Potts' The expressive dimension
Authors: Zimmermann Malte
Published: October 2007

1. Introduction

Christopher Potts has put forward a precise formal analysis of the semantics of expressives, which accounts for their characteristic properties quite well, and which will certainly further our understanding of these expressions. In this short reaction, I concentrate on three aspects where – I think – the proposed analysis of expressives is in need of refinement, or where it is in need of complementation. The three aspects concern (i) the suggested non-accessibility of expressive content to the descriptive meaning dimension; (ii) the internal structure of expressive indices and the nature of index-changing operations; (iii) and the semantic behavior of discourse particles in relation to expressives proper.
The centrality of expressive indices
Authors: Potts Christopher
Published: October 2007

1. Introduction

Without exception, the commentaries on my paper help further develop and refine the theory of expressives. They approach the expressive dimension from diverse theoretical perspectives, and they leave us with important new data. There is not space in this reply to do justice to all the points raised, so I instead highlight and reexamine the main themes.
Bihemispheric Leftward Bias in a Visuospatial Attention-Related Network
Authors: Siman-Tov Tali , Mendelsohn Avi , Schonberg Tom , Avidan Galia , Podlipsky Ilana , Pessoa Luiz , Gadoth Natan , Ungerleider Leslie G. , Hendler Talma
Published: October 2007

Asymmetry of spatial attention has long been described in both disease (hemispatial neglect) and healthy (pseudoneglect) states. Although right-hemisphere specialization for spatial attention has been suggested, the exact neural mechanisms of asymmetry have not been deciphered yet. A recent functional magnetic resonance imaging study from our laboratory serendipitously revealed bihemispheric left-hemifield superiority in activation of a visuospatial attention-related network. Nineteen right-handed healthy adult females participated in two experiments of visual half-field presentation. Either facial expressions (experiment 1) or house images (experiment 2) were presented unilaterally and parafoveally for 150 ms while subjects were engaging a central fixation task. Brain regions previously associated with a visuospatial attention network, in both hemispheres, were found to be more robustly activated by left visual field stimuli. The consistency of this finding with manifestations of attention lateralization is discussed, and a revised model based on neural connectivity asymmetry is proposed. Support for the revised model is given by a dynamic causal modeling analysis. Unraveling the basis for attention asymmetry may lead to better understanding of the pathogenesis of attention disorders, followed by improved diagnosis and treatment. Additionally, the proposed model for asymmetry of visuospatial attention might provide important insights into the mechanisms underlying functional brain lateralization in general.
Conditional Knock-Out of Kir4.1 Leads to Glial Membrane Depolarization, Inhibition of Potassium and Glutamate Uptake, and Enhanced Short-Term Synaptic Potentiation
Authors: Djukic Biljana , Casper Kristen B. , Philpot Benjamin D. , Chin Lih-Shen , McCarthy Ken D.
Published: October 2007

During neuronal activity, extracellular potassium concentration ([K+]out) becomes elevated and, if uncorrected, causes neuronal depolarization, hyperexcitability, and seizures. Clearance of K+from the extracellular space, termed K+spatial buffering, is considered to be an important function of astrocytes. Results from a number of studies suggest that maintenance of [K+]outby astrocytes is mediated by K+uptake through the inward-rectifying Kir4.1 channels. To study the role of this channel in astrocyte physiology and neuronal excitability, we generated a conditional knock-out (cKO) of Kir4.1 directed to astrocytes via the human glial fibrillary acidic protein promotergfa2. Kir4.1 cKO mice die prematurely and display severe ataxia and stress-induced seizures. Electrophysiological recordings revealed severe depolarization of both passive astrocytes and complex glia in Kir4.1 cKO hippocampal slices. Complex cell depolarization appears to be a direct consequence of Kir4.1 removal, whereas passive astrocyte depolarization seems to arise from an indirect developmental process. Furthermore, we observed a significant loss of complex glia, suggestive of a role for Kir4.1 in astrocyte development. Kir4.1 cKO passive astrocytes displayed a marked impairment of both K+and glutamate uptake. Surprisingly, membrane and action potential properties of CA1 pyramidal neurons, as well as basal synaptic transmission in the CA1 stratum radiatum appeared unaffected, whereas spontaneous neuronal activity was reduced in the Kir4.1 cKO. However, high-frequency stimulation revealed greatly elevated posttetanic potentiation and short-term potentiation in Kir4.1 cKO hippocampus. Our findings implicate a role for glial Kir4.1 channel subunit in the modulation of synaptic strength.
Behavioral Discrimination between Sucrose and Other Natural Sweeteners in Mice: Implications for the Neural Coding of T1R Ligands
Authors: Dotson Cedrick D. , Spector Alan C.
Published: October 2007

In taste bud cells, two different T1R heteromeric taste receptors mediate signal transduction of sugars (the canonical “sweet” taste receptor, T1R2 + T1R3) andl-amino acids (the T1R1 + T1R3 receptor). The T1R1 + T1R3 receptor is thought to mediate what is considered the fifth basic taste quality “umami.” However, a subset ofl-amino acids is “sweet tasting” to humans and appears to possess a “sucrose-like” taste quality to nonhuman mammals. This suggests, to varying degrees, that all of these compounds activate a single neural channel that leads to the perception of sweetness.

The experiments detailed here were designed to test the ability of mice to distinguish between sucrose and various others sugars andl-amino acids in operant taste discrimination tasks. Mice had at least some difficulty discriminating sucrose froml-serine,l-threonine, maltose, fructose, and glucose. For example, when concentration effects are taken into consideration, mice discriminated poorly, if at all, sucrose from glucose or fructose and, to a lesser extent maltose, suggesting that sugars generate a unitary perceptual quality. However, mice were able to reliably discriminate sucrose froml-serine andl-threonine. Data gathered using a conditioned taste aversion assay also suggest that, although qualitatively similar to the taste of sucrose,l-serine andl-threonine generate distinctive percepts.

In conclusion, it appears that some signals from taste receptor proteins binding with sugars and somel-amino acids converge somewhere along the gustatory neuraxis. However, the results of these experiments also imply that sweet-tastingl-amino acids may possess qualitative taste characteristics that are distinguishable from the prototypical sweetener sucrose.
How Progesterone Impairs Memory for Biologically Salient Stimuli in Healthy Young Women
Authors: van Wingen Guido , van Broekhoven Frank , Verkes Robbert Jan , Petersson Karl Magnus , Bäckström Torbjörn , Buitelaar Jan , Fernández Guillén
Published: October 2007

Progesterone, or rather its neuroactive metabolite allopregnanolone, modulates amygdala activity and thereby influences anxiety. Cognition and, in particular, memory are also altered by allopregnanolone. In the present study, we investigated whether allopregnanolone modulates memory for biologically salient stimuli by influencing amygdala activity, which in turn may affect neural processes in other brain regions. A single progesterone dose was administered orally to healthy young women in a double-blind, placebo-controlled, crossover design, and participants were asked to memorize and recognize faces while undergoing functional magnetic resonance imaging. Progesterone decreased recognition accuracy without affecting reaction times. The imaging results show that the amygdala, hippocampus, and fusiform gyrus supported memory formation. Importantly, progesterone decreased responses to faces in the amygdala and fusiform gyrus during memory encoding, whereas it increased hippocampal responses. The progesterone-induced decrease in neural activity in the amygdala and fusiform gyrus predicted the decrease in memory performance across subjects. However, progesterone did not modulate the differential activation between subsequently remembered and subsequently forgotten faces in these areas. A similar pattern of results was observed in the fusiform gyrus and prefrontal cortex during memory retrieval. These results suggest that allopregnanolone impairs memory by reducing the recruitment of those brain regions that support memory formation and retrieval. Given the important role of the amygdala in the modulation of memory, these results suggest that allopregnanolone alters memory by influencing amygdala activity, which in turn may affect memory processes in other brain regions.
Neurotoxic Lesions of the Medial Mediodorsal Nucleus of the Thalamus Disrupt Reinforcer Devaluation Effects in Rhesus Monkeys
Authors: Mitchell Anna S. , Browning Philip G. F. , Baxter Mark G.
Published: October 2007

The mediodorsal thalamus is a major input to the prefrontal cortex and is thought to modulate cognitive functions of the prefrontal cortex. Damage to the medial, magnocellular part of the mediodorsal thalamus (MDmc) impairs cognitive functions dependent on prefrontal cortex, including memory. The contribution of MDmc to other aspects of cognition dependent on prefrontal cortex has not been determined. The ability of monkeys to adjust their choice behavior in response to changes in reinforcer value, a capacity impaired by lesions of orbital prefrontal cortex, can be tested in a reinforcer devaluation paradigm. In the present study, rhesus monkeys with bilateral neurotoxic MDmc lesions were tested in the devaluation procedure. Monkeys learned visual discrimination problems in which each rewarded object is reliably paired with one of two different food rewards and then were given choices between pairs of rewarded objects, one associated with each food. Selective satiation of one of the food rewards reduces choices of objects associated with that food in normal monkeys. Monkeys with bilateral neurotoxic lesions of MDmc learned concurrently presented visual discrimination problems as quickly as unoperated control monkeys but showed impaired reinforcer devaluation effects. This finding suggests that the neural circuitry for control of behavioral choice by changes in reinforcer value includes MDmc.
Audiovisual Temporal Correspondence Modulates Human Multisensory Superior Temporal Sulcus Plus Primary Sensory Cortices
Authors: Noesselt Toemme , Rieger Jochem W. , Schoenfeld Mircea Ariel , Kanowski Martin , Hinrichs Hermann , Heinze Hans-Jochen , Driver Jon
Published: October 2007

The brain should integrate related but not unrelated information from different senses. Temporal patterning of inputs to different modalities may provide critical information about whether those inputs are related or not. We studied effects of temporal correspondence between auditory and visual streams on human brain activity with functional magnetic resonance imaging (fMRI). Streams of visual flashes with irregularly jittered, arrhythmic timing could appear on right or left, with or without a stream of auditory tones that coincided perfectly when present (highly unlikely by chance), were noncoincident with vision (different erratic, arrhythmic pattern with same temporal statistics), or an auditory stream appeared alone. fMRI revealed blood oxygenation level-dependent (BOLD) increases in multisensory superior temporal sulcus (mSTS), contralateral to a visual stream when coincident with an auditory stream, and BOLD decreases for noncoincidence relative to unisensory baselines. Contralateral primary visual cortex and auditory cortex were also affected by audiovisual temporal correspondence or noncorrespondence, as confirmed in individuals. Connectivity analyses indicated enhanced influence from mSTS on primary sensory areas, rather than vice versa, during audiovisual correspondence. Temporal correspondence between auditory and visual streams affects a network of both multisensory (mSTS) and sensory-specific areas in humans, including even primary visual and auditory cortex, with stronger responses for corresponding and thus related audiovisual inputs.
Endogenous Transforming Growth Factor β1 Suppresses Inflammation and Promotes Survival in Adult CNS
Authors: Makwana Milan , Jones Leonard L. , Cuthill Dan , Heuer Heike , Bohatschek Marion , Hristova Mariya , Friedrichsen Sönke , Ormsby Ilona , Bueringer Dietmute , Koppius Andrea , Bauer Karl , Doetschman Thomas , Raivich Gennadij
Published: October 2007

Transforming growth factor β1 (TGFβ1) is a pleiotropic cytokine with potent neurotrophic and immunosuppressive properties that is upregulated after injury, but also expressed in the normal nervous system. In the current study, we examined the regulation of TGFβ1 and the effects of TGFβ1 deletion on cellular response in the uninjured adult brain and in the injured and regenerating facial motor nucleus. To avoid lethal autoimmune inflammation within 3 weeks after birth in TGFβ1-deficient mice, this study was performed on a T- and B-cell-deficient RAG2−/− background. Compared with wild-type siblings, homozygous deletion of TGFβ1 resulted in an extensive inflammatory response in otherwise uninjured brain parenchyma. Astrocytes increased in GFAP and CD44 immunoreactivity; microglia showed proliferative activity, expression of phagocytosis-associated markers [αXβ2, B7.2, and MHC1 (major histocompatibility complex type 1)], and reduced branching. Ultrastructural analysis revealed focal blockade of axonal transport, perinodal damming of axonal organelles, focal demyelination, and myelin debris in granule-rich, phagocytic microglia. After facial axotomy, absence of TGFβ1 led to a fourfold increase in neuronal cell death (52 vs 13%), decreased central axonal sprouting, and significant delay in functional recovery. It also interfered with the microglial response, resulting in a diminished expression of early activation markers [ICAM1 (intercellular adhesion molecule 1), α6β1, and αMβ2] and reduced proliferation. In line with axonal and glial findings in the otherwise uninjured CNS, absence of endogenous TGFβ1 also caused an ∼10% reduction in the number of normal motoneurons, pointing to an ongoing and potent trophic role of this anti-inflammatory cytokine in the normal as well as in the injured brain.
Cyclooxygenase-1-Derived Prostaglandins in the Periaqueductal Gray Differentially Control C- versus A-Fiber-Evoked Spinal Nociception
Authors: Leith J. Lianne , Wilson Alex W. , Donaldson Lucy F. , Lumb Bridget M.
Published: October 2007

Nonsteroidal anti-inflammatory drugs (NSAIDs) exert analgesic effects by inhibiting peripheral cyclooxygenases (COXs). It is now clear that these drugs also have central actions that include the modulation of descending control of spinal nociception from the midbrain periaqueductal gray (PAG). Descending control is a powerful determinant of the pain experience and is thus a potential target for analgesic drugs, including COX inhibitors. Noxious information from the periphery is conveyed to the spinal cord in A- and C-fiber nociceptors, which convey different qualities of the pain signal and have different roles in chronic pain. Thisin vivostudy used different rates of skin heating to preferentially activate A- or C-heat nociceptors to further investigate the actions of COX inhibitors and prostaglandins in the PAG on spinal nociceptive processing. The results significantly advance our understanding of the central mechanisms underlying the actions of NSAIDs and prostaglandins by demonstrating that (1) in the PAG, it is COX-1 and not COX-2 that is responsible for acute antinociceptive effects of NSAIDsin vivo; (2) these effects are only evoked from the opioid-sensitive ventrolateral PAG; and (3) prostaglandins in the PAG exert tonic facilitatory control that targets C- rather than A-fiber-mediated spinal nociception. This selectivity of control is of particular significance given the distinct roles of A- and C-nociceptors in acute and chronic pain. Thus, effects of centrally acting prostaglandins are pivotal, we suggest, to both the understanding of nociceptive processing and the development of new analgesic drugs.
Tyrosine Phosphorylation Sites in ephrinB2 Are Required for Hippocampal Long-Term Potentiation But Not Long-Term Depression
Authors: Bouzioukh Farima , Wilkinson George A. , Adelmann Giselind , Frotscher Michael , Stein Valentin , Klein Rüdiger
Published: October 2007

Long-lasting changes in synaptic function are thought to be the cellular basis for learning and memory and for activity-dependent plasticity during development. Long-term potentiation (LTP) and long-term depression (LTD) are two opposing forms of synaptic plasticity that help fine tune neural connections and possibly serve to store information in the brain. Eph receptor tyrosine kinases and their transmembrane ligands, the ephrinBs, have essential roles in certain forms of synaptic plasticity. At the CA3–CA1 hippocampal synapse, EphB2 and EphA4 receptors are critically involved in long-term plasticity independent of their cytoplasmic domains, suggesting that ephrinBs are the active signaling partners. In cell-based assays, ephrinB reverse signaling was previously shown to involve phosphotyrosine-dependent and postsynaptic density-95/Discs large/zona occludens-1 (PDZ) domain interaction-dependent pathways. Which reverse signaling mode is required at hippocampal synapses is unknown. To address this question, we used knock-in mice expressing mutant isoforms of ephrinB2 that are deficient in specific aspects of reverse signaling. Our analysis revealed that tyrosine phosphorylation sites in ephrinB2 are required to mediate normal hippocampal LTP, but not for LTD. Conversely, ephrinB2 lacking the C-terminal PDZ interaction site, but competent to undergo tyrosine phosphorylation, cannot mediate either form of long-term plasticity. Our results provide the first evidence for phosphotyrosine-dependent ephrinB reverse signaling in a neuronal network and for differential ephrinB2 reverse signaling in two forms of synaptic plasticity.
The Long Form of Fas Apoptotic Inhibitory Molecule Is Expressed Specifically in Neurons and Protects Them against Death Receptor-Triggered Apoptosis
Authors: Segura Miguel F. , Sole Carme , Pascual Marta , Moubarak Rana S. , Jose Perez-Garcia M. , Gozzelino Raffaella , Iglesias Victoria , Badiola Nahuai , Bayascas Jose R. , Llecha Nuria , Rodriguez-Alvarez Jose , Soriano Eduardo , Yuste Victor J. , Comella Joan X.
Published: October 2007

Death receptors (DRs) and their ligands are expressed in developing nervous system. However, neurons are generally resistant to death induction through DRs and rather their activation promotes neuronal outgrowth and branching. These results suppose the existence of DRs antagonists expressed in the nervous system. Fas apoptosis inhibitory molecule (FAIMS) was first identified as a Fas antagonist in B-cells. Soon after, a longer alternative spliced isoform with unknown function was identified and named FAIML. FAIMSis widely expressed, including the nervous system, and we have shown previously that it promotes neuronal differentiation but it is not an anti-apoptotic molecule in this system. Here, we demonstrate that FAIMLis expressed specifically in neurons, and its expression is regulated during the development. Expression could be induced by NGF through the extracellular regulated kinase pathway in PC12 (pheochromocytoma cell line) cells. Contrary to FAIMS, FAIMLdoes not increase the neurite outgrowth induced by neurotrophins and does not interfere with nuclear factor κB pathway activation as FAIMSdoes. Cells overexpressing FAIMLare resistant to apoptotic cell death induced by DRs such as Fas or tumor necrosis factor R1. Reduction of endogenous expression by small interfering RNA shows that endogenous FAIMLprotects primary neurons from DR-induced cell death. The detailed analysis of this antagonism shows that FAIMLcan bind to Fas receptor and prevent the activation of the initiator caspase-8 induced by Fas. In conclusion, our results indicate that FAIMLcould be responsible for maintaining initiator caspases inactive after receptor engagement protecting neurons from the cytotoxic action of death ligands.
Rapid Activation of Antioxidant Defenses by Nerve Growth Factor Suppresses Reactive Oxygen Species during Neuronal Apoptosis: Evidence for a Role in CytochromecRedistribution
Authors: Kirkland Rebecca A. , Saavedra Geraldine M. , Franklin James L.
Published: October 2007

Depriving mouse sympathetic neurons of nerve growth factor (NGF) causes their apoptotic death. A Bax-dependent increase of mitochondrial-derived reactive oxygen species (ROS) begins in these cells soon after NGF withdrawal. We investigated the effects on these ROS of adding NGF to cultures of NGF-deprived neurons. ROS levels were monitored with the fluorescent, redox-sensitive dyes CM-H2DCFDA and MitoSOX Red. The intensity of the former dye increases when it is oxidized by H2O2and free radicals downstream of H2O2. MitoSOX Red is relatively insensitive to oxidation by H2O2but is sensitive to oxidation by superoxide (O2.−). Withdrawing NGF increased CM-H2DCFDA intensity, indicating elevated H2O2-associated ROS. Re-exposure of cells deprived of NGF to NGF resulted in rapid suppression of these ROS. Neurons deprived of NGF also had increased MitoSOX Red intensities. Readdition of NGF had no effect on MitoSOX Red fluorescence. The suppression of CM-H2DCFDA-detected ROS by NGF was caused by a rapid activation of glutathione redox cycling. The most likely explanation for these findings is that mitochondria increased O2.−production after NGF withdrawal. The O2.−was converted to H2O2by dismutation, and the H2O2was detoxified by accelerated glutathione redox cycling. Our previous work shows that H2O2induces cytochromecto be released from mitochondria in NGF-supported sympathetic neurons, whereas antioxidants that detoxify H2O2block cytochromecredistribution in NGF-deprived neurons. Readdition of NGF also immediately inhibits cytochromecrelease. We present evidence that this inhibition is mediated by the rapid activation of glutathione redox cycling by NGF.
Maya Coffee Farmers and Fair Trade: Assessing the Benefits and Limitations of Alternative Markets
Authors: Lyon Sarah
Published: October 2007

Fair trade is a form of alternative trade that seeks to improve the position of disempowered producers through trade as a means of development. It has also been celebrated as a contemporary social movement that contests the conventional agrofood system and its exploitative social and environmental relations of production. In this article, I employ the results of 20 months of ethnographic research in Guatemala and the United States to evaluate fair trade's potential as a form of alternative development. The research demonstrates that fair‐trade market participation can offer a variety of potential benefits to producers, including higher prices, stable market access, organizational capacity building, market information, and access to credit. However, I also identify several key limitations of fair‐trade markets, such as increasing debt burdens, insufficient compensation, the potential for growing inequality, and a lack of cooperative member participation in the fair‐trade movement's international decision making and agenda setting.
Learning from the Tiv: Why a Sustainable Economy Would Have to Be "Multicentric"
Authors: Hornborg Alf
Published: October 2007

Although careful not to romanticize the premodern cultures that have traditionally been the central object of their research, anthropologists might reconsider some classical ethnography in the light of ongoing deliberations on sustainability. Economic anthropology is in a unique position to achieve a distanced view of modern money and neoliberal market ideology by contrasting its notions of value and reciprocity with those of premodern, "multicentric" economies such as that documented over 50 years ago by Paul Bohannan among the Tiv of Nigeria. The assumptions of generalized interchangeability and abstract utility that are so fundamental to the theory and practice of neoclassical economics inexorably generate an accelerating destruction of natural resources and increasingly inequitable global trade relations. The fundamental principle of any "multicentric" economy is the acknowledgment of two or more distinct and incommensurable spheres of value. This principle deserves to be reexamined by economic policy makers seriously committed to improving local control of resources, sustainability, and equity. The challenge could be expressed in terms of "immunizing" local meanings and ecosystems against the conceptual and physical ravages of global capital. In this article, I discuss some aspects of the rationale of alternative markets and currencies, emphasizing the peculiarly dissolvent semiotics of "general purpose money" in a biosphere organized in terms of hierarchically nested levels of integration. I also sketch some fundamental considerations that such alternative economies would have to incorporate to stand a chance of curbing the dissipative logic of modern money.
The Interests of Competing Elites: Fighting over Protectionism and "Free Markets" in Philippine Sugar
Authors: Billig Michael S.
Published: October 2007

Although scholars often view the Philippines as still dominated by rural agrarian elites, this image is increasingly a distortion. Urban industrial, commercial, and financial elites are becoming more and more dominant, both economically and culturally. In this article, I describe a conflict between the sugar and the food processing industries, in which the former advocated that sugar be protected from imports and the latter argued in favor of a "free market" in sugar. The defeat suffered by the once‐influential sugar industry illustrates the extent to which dominance has shifted in the Philippines and also how the rhetoric of the free market reflects the interests of an emerging dominant reference group. As dominant economic interests become less restricted by national borders, they will increasingly demand the ability to import raw materials, export labor, and move goods and capital in and out at lower cost. Debates about the relative merits of protectionist versus free market policies are less about principles for maximizing social welfare and more about which segment of elites has the power and standing to press its interests most effectively.
Selling Coffee, or Selling Out?: Evaluating Different Ways to Analyze the Fair‐Trade System
Authors: Fisher Carolyn
Published: October 2007

Consumers have been increasingly associating gourmet coffee with ethical questions in recent years, leading to a confusing array of claims by retailers about how coffee farmers are treated. Among these competing claims, fair trade stands out as the only system to have wide activist support. Is fair trade just another marketing claim? A consumption paradigm shift? Or a social movement? In this article, I review three potential interpretations of fair trade: as the partial introduction of gifting into a market context, as the commodification of new realms, and as a social movement. I conclude that seeing fair trade as gifting overdraws the difference between fair trade and other commerce, failing to take into account research that blurs the differences between gift and commodity and obscuring the considerable power inequalities in the system. It makes sense to see fair trade as the commodification of activism. And we can see the fair‐trade system as a social movement with active participants and more passive supporters. Ultimately, we should not characterize the entire system as one phenomenon, but see it as articulating modes of social transformation. I conclude with a discussion of the moral connotations of each interpretation.
Research and Moral Law: Ethics and the Social Science Research Relation
Authors: Swiffen Amy
Published: October 2007

This paper explores the ethics of social science research by taking the Canadian context as a case study of the increasing formalization of ethics review procedures in North America. Based on a biomedical model of harm prevention, all university research involving humans in Canada, regardless of discipline, must pass through an ethics board review. I read the official ethics policy document governing review procedures for human research in Canada and use two examples of criticism of such policy as entry points to identify and explore a limit in understandings of social research ethics. This limit is reached when ethics policy is criticized on the basis of the incompatibility of a general rule applied to a particular research situation. Using concepts from the ethical philosophies of Kant and Lacan, I move beyond the question of the application of general rules to particular research situations and push research ethics into different territory, where neither general rules nor the notion of particularity can be relied on to ground ethical action. In this other terrain, radical responsibility and unguaranteed decision are the only signposts.
Comparative "Research": A Modest Proposal concerning the Object of Ethics Regulation
Authors: Lederman Rena
Published: October 2007

Complementing the broader project of treating human subjects research regulation (including "informed consent") as an ethnographic object, this article scrutinizes the category research: that about which research subjects may (in some way) be informed, to which they may (or may not) consent, and in which they may (variously) participate. What is "research"? When does it begin and end? What is the relationship between its demarcations as a regulatory object and its demarcations in the everyday practices of knowledge production? Federal research ethics regulations take for granted that research can be distinguished from nonresearch and subjected to distinctive constraints. The regulations also presume an idealized scientific method with predetermined spaces, times, personnel, and procedures. Although such clarity is difficult for many kinds of human subjects research, it is impossible for ethnographic fieldwork. A modest proposal is offered concerning with whom ethnographers might make common cause.
Book Review
Authors: Guyer Jane I.
Published: October 2007

The Pan African Nation: Oil and the Spectacle of Culture in Nigeria By Andrew Apter. Chicago. University of Chicago Press. 2005.
Book Review
Authors: Sridhar Devi
Published: October 2007

Playing at Politics: An Ethnography of the Oxford Union By Fiona Graham. Edinburgh. Dunedin Academic Press. 2005.
Book Review
Authors: Haenn Nora
Published: October 2007

Mayan Voices for Human Rights: Displaced Catholics in Highland Chiapas By Christine Kovic. Austin. University of Texas Press. 2005.
Book Review
Authors: Kornhauser Ann
Published: October 2007

The Modern Art of Dying:. History of Euthanasia in the United States By Shai J. Lavi. Princeton. Princeton University Press. 2005.
Book Review
Authors: Holden Livia
Published: October 2007

Navajo Nation Peacemaking: Living Traditional Justice By Marianne O. Nielsen and James W. Zion, editors. Tucson. University of Arizona Press. 2005.
Book Review
Authors: Coleman Amanda
Published: October 2007

Shadows of War: Violence, Power, and International Profiteering in the Twenty‐first Century By Carolyn Nordstrom. Berkeley. University of California Press. 2004.
Az ovidiusi fakatalógus (Met. 10, 90-106) és a Metamorphoses esztétikája
Authors: Acél Zsolt
Published: October 2007

Ovidius
Metamorphoses
című
művének fakatalógusa (10, 90—106) a mű nehezen értelmezhető részei közé
tartozik. A tizedik könyv motívumk_0
Az öröklés kérdése Vespasianus idejében
Authors: Székely Melinda
Published: October 2007

Vespasianus
uralomra kerülése után a dinasztikus politika elvét követte, a
senatus
i
ellenzék és a kor köztársasági érzelmű gondolkodói azonban a sztoikus_0
Evidências do impacto da suplementação de vitamina A no grupo materno-infantil
Authors: Oliveira Julicristie Machado de , Rondó Patrícia Helen de Carvalho
Published: October 2007

O objetivo deste artigo é reunir os resultados de revisões sistemáticas e metanálises sobre o efeito da suplementação de vitamina A no crescimento, morbi-mortalidade infantil, materna e fetal. Foi realizada uma busca criteriosa nas bases de dados bibliográficos PubMed, Embase, LILACS, PAHO, Biblioteca Cochrane, Banco de Teses da CAPES, Biblioteca Digital de Teses da USP e acervo da Biblioteca Central da UNIFESP, localizando-se 14 trabalhos publicados entre 1993 e 2006. Há evidências de que a suplementação de vitamina A em crianças esteja associada à redução de 23% a 30% no risco de morte e atenuação da gravidade do quadro de sarampo e diarréia. Não há evidências de que a intervenção em crianças reduza a incidência de pneumonia não associada ao sarampo e mortalidade por essa causa. Em crianças e gestantes com HIV/AIDS, a suplementação apresenta impacto positivo na morbi-mortalidade infantil e no peso ao nascer. Não há evidências de que a suplementação em gestantes e lactantes esteja associada à redução da morbi-mortalidade infantil, mas há indicação de que essa intervenção seja protetora em relação à morbidade materna.
Qual deficiência?: perícia médica e assistência social no Brasil
Authors: Diniz Debora , Squinca Flávia , Medeiros Marcelo
Published: October 2007

Este artigo analisa o conceito de deficiência adotado pela principal política de transferência de renda para a população portadora de deficiência no Brasil, o Benefício de Prestação Continuada (BPC). O estudo contrasta os critérios de seleção regulamentados pelo programa aos critérios utilizados pelos médicos peritos encarregados de avaliar e selecionar os beneficiários do programa. Foi realizada uma pesquisa por amostra com 16% do total de médicos peritos no Brasil. O objetivo do questionário foi avaliar a qualidade das instruções, dos formulários e dos procedimentos relativos à elegibilidade das pessoas deficientes ao benefício. Os resultados mostram que há uma divergência entre os critérios formais que regulamentam o BPC e a prática pericial dos médicos que apontam para um alargamento do conceito de deficiência para a inclusão de beneficiários com doenças genéticas, crônicas e infecciosas graves.
Queixas osteomusculares relacionadas ao trabalho relatadas por mulheres de centro de ressocialização
Authors: Pastre Eliane Cristina , Carvalho Filho Guaracy , Pastre Carlos Marcelo , Padovani Carlos Roberto , Almeida Josiane Schadeck de , Netto Júnior Jayme
Published: October 2007

Considerando as queixas de origem laboral um problema de saúde pública, objetivou-se, com o presente estudo, analisar a freqüência da população que refere queixas osteomusculares e a associação de ocorrência e severidade destas às variáveis antropométricas e de trabalho. Tomou-se 146 mulheres de um centro de ressocialização feminino, que responderam a um questionário validado contendo informações sobre dados antropométricos e queixas osteomusculares relacionadas ao trabalho. O estudo da associação entre e dentro das variáveis foi feito pelo teste de Goodman. Observou-se elevada freqüência de ocorrência de queixas após início de atividade laboral (94,19%). As participantes com necessidade de afastamento apresentaram maiores valores em idade e peso. Queixa acentuada foi mais referida na coluna do tronco. Afastamento foi mais referido para as que trabalhavam há mais tempo. Concluiu-se que é alta a freqüência de queixas relacionadas ao trabalho e que há associação entre maiores valores de peso e de estatura e nível de severidade acentuado; maiores valores de idade e de peso e necessidade de afastamento; níveis acentuados de queixas e região da coluna e entre maior tempo de serviço e necessidade de afastamento.
Terapia de reposição hormonal e o câncer do endométrio
Authors: Araújo Júnior Naidilton Lantyer Cordeiro de , Athanazio Daniel Abensur
Published: October 2007

A reposição hormonal para alívio dos sintomas menopausais é amplamente utilizada em todo o mundo. A evolução do conhecimento sobre os riscos deste tratamento sempre foi mais lenta do que sua aplicação na prática clínica. Na década de 70, um aumento de incidência de câncer do endométrio ocorreu nos países desenvolvidos sendo que a terapia de estrógenos exógenos na menopausa foi o principal fator relacionado. Nas décadas de 80 e 90, a combinação entre estrógenos e progestínicos passou a ser largamente utilizada com base na premissa de que apresentava efeitos benéficos sobre os sistemas cardiovascular e osteoarticular, sem aumento no risco de câncer uterino. Entretanto, relatos recentes novamente questionam a segurança da reposição hormonal e, desta vez, apontam para o risco maior de câncer total e doença cardiovascular nos esquemas combinados. Concluímos neste trabalho que os riscos recentemente relacionados à terapia combinada têm grande potencial de impacto na Saúde Pública, e este esquema não é indicado para proteção do risco de carcinoma endometrial uma vez que seus riscos superam os benefícios.