bluuebunny/crossref_metadata_2025 huggingface dataset:
CCK2receptor nullification attenuates lipopolysaccharide-induced sickness behavior
Authors: Weiland Tracey J. , Voudouris Nicholas J. , Kent Stephen
Published: July 2006

Systemic infection produces a highly regulated set of responses such as fever, anorexia, adipsia, inactivity, and cachexia, collectively referred to as sickness behavior. Although the expression of sickness behavior requires immune-brain communication, the mechanisms by which peripheral cytokines signal the brain are unclear. Several mechanisms have been proposed for neuroimmune communication, including the interaction of cytokines with peripheral nerves. A critical role has been ascribed to the vagus nerve in mediating sickness behavior after intraperitoneally delivered immune activation, and converging evidence suggests that this communication may involve neurochemical intermediaries afferent and/or efferent to this nerve. Mice lacking functional CCK2/gastrinreceptors (CCK2KO) and wild-type (WT) controls were administered LPS (50, 500, or 2,500 μg/kg; serotype 0111:B4; ip). Results indicate a role for CCK2receptor activation in the initiation and maintenance of LPS-induced sickness behavior. Compared with WT controls, CCK2KO mice were significantly less affected by LPS on measures of body temperature, activity, body weight, and food intake, with the magnitude of effects increasing with increasing LPS dose. Although activation of CCK2receptors at the level of the vagus nerve cannot be excluded, a possible role for these receptors in nonvagal routes of immune-brain communication is suggested.
ANG II type 2 receptors and neural control of intrarenal blood flow
Authors: Rajapakse Niwanthi W. , Eppel Gabriela A. , Widdop Robert E. , Evans Roger G.
Published: July 2006

We tested the hypothesis that activation of angiotensin type 2 (AT2) receptors, by both exogenous and endogenous ANG II, modulates neurally mediated vasoconstriction in the renal cortical and medullary circulations. Under control conditions in pentobarbital-anesthetized rabbits, electrical stimulation of the renal nerves (RNS; 0.5–8 Hz) reduced renal blood flow (RBF; −88 ± 3% at 8 Hz) and cortical perfusion (CBF; −92 ± 2% at 8 Hz) more than medullary perfusion (MBF; −67 ± 6% at 8 Hz). Renal arterial infusion of ANG II, at a dose titrated to reduce RBF by ∼40–50% (5–50 ng·kg−1·min−1) blunted responses of MBF to RNS, without significantly affecting responses of RBF or CBF. Subsequent administration of PD123319 (1 mg/kg plus 1 mg·kg−1·h−1) during continued renal arterial infusion of ANG II did not significantly affect responses of RBF or CBF to RNS but enhanced responses of MBF, so that they were similar to those observed under control conditions. In contrast, administration of PD123319 alone blunted responses of CBF and MBF to RNS. Subsequent renal arterial infusion of ANG II in PD123319 -pretreated rabbits restored CBF responses to RNS back to control levels. In contrast, ANG II infusion in PD123319 -pretreated rabbits did not alter MBF responses to RNS. These data indicate that exogenous ANG II can blunt neurally mediated vasoconstriction in the medullary circulation through activation of AT2 receptors. However, AT2-receptor activation by endogenous ANG II appears to enhance neurally mediated vasoconstriction in both the cortical and medullary circulations.
Inhibition of cyclooxygenase isoforms in late- but not midgestation decreases contractility of the ductus arteriosus and prevents postnatal closure in mice
Authors: Reese Jeff , Anderson Judy D. , Brown Naoko , Roman Christine , Clyman Ronald I.
Published: July 2006

Use of cyclooxygenase (COX) inhibitors to delay preterm birth is complicated by in utero constriction of the ductus arteriosus and delayed postnatal closure. Delayed postnatal closure has been attributed to loss of vasa vasorum flow and ductus wall ischemia resulting from constriction in utero. We used the murine ductus (which does not depend on vasa vasorum flow) to determine whether delayed postnatal closure may be because of mechanisms independent of in utero constriction. Acute inhibition of both COX isoforms constricted the fetal ductus on days 18 and 19 (term) but not earlier in gestation; COX-2 inhibition constricted the fetal ductus more than COX-1 inhibition. In contrast, mice exposed to prolonged inhibition of COX-1, COX-2, or both COX isoforms (starting on day 15, when the ductus does not respond to the inhibitors) had no contractile response to the inhibitors on days 18 or 19. Newborn mice closed their ductus within 4 h of birth. Prolonged COX inhibition on days 11–14 of gestation had no effect on newborn ductal closure; however, prolonged COX inhibition on days 15–19 resulted in delayed ductus closure despite exposure to 80% oxygen after birth. Similarly, targeted deletion of COX-2 alone, or COX-1/COX-2 together, impaired postnatal ductus closure. Nitric oxide inhibition did not prevent the delay in ductus closure. These data show that impaired postnatal ductus closure is not the result of in utero ductus constriction or upregulation of nitric oxide synthesis. They are consistent with a novel role for prostaglandins in ductus arteriosus contractile development.
The adolescent decline of NREM delta, an indicator of brain maturation, is linked to age and sex but not to pubertal stage
Authors: Feinberg Irwin , Higgins Lisa M. , Khaw Wong Yu , Campbell Ian G.
Published: July 2006

Two dramatic phenomena of human adolescence are sexual maturation and a steep decline in the delta EEG of non-rapid eye movement (NREM) sleep. It has long been speculated that these developmental changes are causally related. Here, we present the first longitudinal data on this issue. Cohorts of 9- and 12-year-old children ( n = 31, 38) were studied with in-home sleep EEG recordings at 6-mo intervals over 2 years. Pubertal (Tanner) stage, height, and weight were obtained at each time point. NREM delta power density (DPD) did not change significantly over ages 9–11 years, and its level did not differ in boys and girls. DPD declined by 25% between ages 12 and 14 years. This decline was parallel in the two sexes, but levels were lower in girls, suggesting that their DPD decline began earlier. Mixed effect analyses demonstrated that DPD was strongly related to age with Tanner stage, height, weight and body mass index controlled but that none of these measures of physical and sexual development was related to DPD with age controlled. NREM delta is the sleep EEG component homeostatically related to prior waking duration and the intensity of waking brain activity. We hypothesize that the DPD decline is caused by age-programmed synaptic pruning that decreases waking brain metabolic rate. This reduced rate would decrease the “substrate” for delta homeostasis. Whether or not this interpretation proves correct, these longitudinal data demonstrate that the delta decline in adolescence reflects brain processes that are not predicted by physical growth or sexual maturation.
The flounder organic anion transporter fOat has sequence, function, and substrate specificity similarity to both mammalian Oat1 and Oat3
Authors: Aslamkhan Amy G. , Thompson Deborah M. , Perry Jennifer L. , Bleasby Kelly , Wolff Natascha A. , Barros Scott , Miller David S. , Pritchard John B.
Published: July 2006

The flounder renal organic anion transporter (fOat) has substantial sequence homology to mammalian basolateral organic anion transporter orthologs (OAT1/Oat1 and OAT3/Oat3), suggesting that fOat may have functional properties of both mammalian forms. We therefore compared uptake of various substrates by rat Oat1 and Oat3 and human OAT1 and OAT3 with the fOat clone expressed in Xenopus oocytes. These data confirm that estrone sulfate is an excellent substrate for mammalian OAT3/Oat3 transporters but not for OAT1/Oat1 transporters. In contrast, 2,4-dichlorophenoxyacetic acid and adefovir are better transported by mammalian OAT1/Oat1 than by the OAT3/Oat3 clones. All three substrates were well transported by fOat-expressing Xenopus oocytes. fOat Kmvalues were comparable to those obtained for mammalian OAT/Oat1/3 clones. We also characterized the ability of these substrates to inhibit uptake of the fluorescent substrate fluorescein in intact teleost proximal tubules isolated from the winter flounder ( Pseudopleuronectes americanus) and killifish ( Fundulus heteroclitus). The rank order of the IC50values for inhibition of cellular fluorescein accumulation was similar to that for the Kmvalues obtained in fOat-expressing oocytes, suggesting that fOat may be the primary teleost renal basolateral Oat. Assessment of the zebrafish ( Danio rerio) genome indicated the presence of a single Oat (zfOat) with similarity to both mammalian OAT1/Oat1 and OAT3/Oat3. The puffer fish ( Takifugu rubripes) also has an Oat (pfOat) similar to mammalian OAT1/Oat1 and OAT3/Oat3 members. Furthermore, phylogenetic analyses argue that the teleost Oat1/3-like genes diverged from a common ancestral gene in advance of the divergence of the mammalian OAT1/Oat1, OAT3/Oat3, and, possibly, Oat6 genes.
Restrained whole body plethysmography for measure of strain-specific and allergen-induced airway responsiveness in conscious mice
Authors: Lofgren Jennifer L. S. , Mazan Melissa R. , Ingenito Edward P. , Lascola Kara , Seavey Molly , Walsh Ashley , Hoffman Andrew M.
Published: July 2006

The mouse is the most extensively studied animal species in respiratory research, yet the technologies available to assess airway function in conscious mice are not universally accepted. We hypothesized that whole body plethysmography employing noninvasive restraint (RWBP) could be used to quantify specific airway resistance (sRaw-RWBP) and airway responsiveness in conscious mice. Methacholine responses were compared using sRaw-RWBP vs. airway resistance by the forced oscillation technique (Raw-FOT) in groups of C57, A/J, and BALB/c mice. sRaw-RWBP was also compared with sRaw derived from double chamber plethysmography (sRaw-DCP) in BALB/c. Finally, airway responsiveness following allergen challenge in BALB/c was measured using RWBP. sRaw-RWBP in C57, A/J, and BALB/c mice was 0.51 ± 0.03, 0.68 ± 0.03, and 0.63 ± 0.05 cm/s, respectively. sRaw derived from Raw-FOT and functional residual capacity (Raw*functional residual capacity) was 0.095 cm/s, approximately one-fifth of sRaw-RWBP in C57 mice. The intra- and interanimal coefficients of variations were similar between sRaw-RWBP (6.8 and 20.1%) and Raw-FOT (3.4 and 20.1%, respectively). The order of airway responsiveness employing sRaw-RWBP was AJ > BALBc > C57 and for Raw-FOT was AJ > BALB/c = C57. There was no difference between the airway responsiveness assessed by RWBP vs. DCP; however, baseline sRaw-RWBP was significantly lower than sRaw-DCP. Allergen challenge caused a progressive decrease in the provocative concentration of methacholine that increased sRaw to 175% postsaline values based on sRaw-RWBP. In conclusion, the technique of RWBP was rapid, reproducible, and easy to perform. Airway responsiveness measured using RWBP, DCP, and FOT was equivalent. Allergen responses could be followed longitudinally, which may provide greater insight into the pathogenesis of chronic airway disease.
Role of Soluble Epoxide Hydrolase in Postischemic Recovery of Heart Contractile Function
Authors: Seubert John M. , Sinal Christopher J. , Graves Joan , DeGraff Laura M. , Bradbury J. Alyce , Lee Craig R. , Goralski Kerry , Carey Michelle A. , Luria Ayala , Newman John W. , Hammock Bruce D. , Falck John R. , Roberts Holly , Rockman Howard A. , Murphy Elizabeth , Zeldin Darryl C.
Published: July 2006

Cytochrome P450 epoxygenases metabolize arachidonic acid to epoxyeicosatrienoic acids (EETs) which are converted to dihydroxyeicosatrienoic acids (DHETs) by soluble epoxide hydrolase (
Ephx2
, sEH). To examine the functional role of sEH in the heart, mice with targeted disruption of the
Ephx2
gene were studied. Hearts from sEH null mice have undetectable levels of sEH mRNA and protein and cannot convert EETs to DHETs. sEH null mice have normal heart anatomy and basal contractile function, but have higher fatty acid epoxide:diol ratios in plasma and cardiomyocyte cell culture media compared with wild type (WT). sEH null hearts have improved recovery of left ventricular developed pressure (LVDP) and less infarction compared with WT hearts after 20 minutes ischemia. Perfusion with the putative EET receptor antagonist 14,15-epoxyeicosa-5(Z)-enoic acid (10 to 100 nmol/L) before ischemia abolishes this cardioprotective phenotype. Inhibitor studies demonstrate that perfusion with phosphatidylinositol-3 kinase (PI3K) inhibitors wortmannin (200 nmol/L) or LY294002 (5 μmol/L), the ATP-sensitive K
+
channel (K
ATP
) inhibitor glibenclamide (1 μmol/L), the mitochondrial K
ATP
(mitoK
ATP
) inhibitor 5-hydroxydecanoate (100 to 200 μmol/L), or the Ca
2+
-sensitive K
+
channel (K
Ca
) inhibitor paxilline (10 μmol/L) abolishes the cardioprotection in sEH null hearts. Consistent with increased activation of the PI3K cascade, sEH null mice exhibit increased cardiac expression of glycogen synthase kinase-3β (GSK-3β) phospho-protein after ischemia. Together, these data suggest that targeted disruption of sEH increases the availability of cardioprotective EETs that work by activating PI3K signaling pathways and K
+
channels.
Neural Response Suppression Predicts Repetition Priming of Spoken Words and Pseudowords
Authors: Orfanidou Eleni , Marslen-Wilson William D. , Davis Matthew H.
Published: July 2006

An important method for studying how the brain processes familiar stimuli is to present the same item on more than one occasion and measure how responses change with repetition. Here we use repetition priming in a sparse functional magnetic resonance imaging (fMRI) study to probe the neuroanatomical basis of spoken word recognition and the representations of spoken words that mediate repetition priming effects. Participants made lexical decisions to words and pseudowords spoken by a male or female voice that were presented twice, with half of the repetitions in a different voice. Behavioral and neural priming was observed for both words and pseudowords and was not affected by voice changes. The fMRI data revealed an elevated response to words compared to pseudowords in both posterior and anterior temporal regions, suggesting that both contribute to word recognition. Both reduced and elevated activation for second presentations (repetition suppression and enhancement) were observed in frontal and posterior regions. Correlations between behavioral priming and neural repetition suppression were observed in frontal regions, suggesting that repetition priming effects for spoken words reflect changes within systems involved in generating behavioral responses. Based on the current results, these processes are sufficiently abstract to display priming despite changes in the physical form of the stimulus and operate equivalently for words and pseudowords.
Cortical Mechanisms Involved in the Processing of Verbs: An fMRI Study
Authors: Yokoyama Satoru , Miyamoto Tadao , Riera Jorge , Kim Jungho , Akitsuki Yuko , Iwata Kazuki , Yoshimoto Kei , Horie Kaoru , Sato Shigeru , Kawashima Ryuta
Published: July 2006

In this study, we investigated two aspects of verb processing: first, whether verbs are processed differently from nouns; and second, how verbal morphology is processed. For this purpose, we used functional magnetic resonance imaging to compare three types of lexical processing in Japanese: the processing of nouns, unmarked active verbs, and inflected passive verbs. Twenty-eight healthy subjects were shown a lexical item and asked to judge whether the presented item was a legal word. Although all three conditions activated the bilateral inferior frontal, occipital, the left middle, and inferior temporal cortices, we found differences in the degree of activation for each condition. Verbs elicited greater activation in the left middle temporal gyrus than nouns, and inflected verbs showed greater activation in the left inferior frontal gyrus than unmarked verbs. This study demonstrates that although verbs are basically processed in the same cortical network as nouns, nouns and verbs elicit different degrees of activation due to the cognitive demands involved in lexical semantic processing. Furthermore, this study also shows that the left inferior frontal cortex is related to the processing of verbal inflectional morphology.
Automaticity and Reestablishment of Executive Control—An fMRI Study
Authors: Kübler Andrea , Dixon Veronica , Garavan Hugh
Published: July 2006

The ability to exert control over automatic behavior is of particular importance as it allows us to interrupt our behavior when the automatic response is no longer adequate or even dangerous. However, despite the literature that exists on the effects of practice on brain activation, little is known about the neuroanatomy involved in reestablishing executive control over previously automatized behavior. We present a visual search task that enabled participants to automatize according to defined criteria within about 3 hr of practice and then required them to reassert control without changing the stimulus set. We found widespread cortical activation early in practice. Activation in all frontal areas and in the inferior parietal lobule decreased significantly with practice. Only selected prefrontal (Brodmann's areas [BAs] 9/46/8) and parietal areas (BAs 39/40) were specifically reactivated when executive control was required, underlining the crucial role of the dorsolateral prefrontal cortex in executive control to guide our behavior.
Cross-modal Interactions in Time and Space: Auditory Influence on Visual Attention in Hemispatial Neglect
Authors: Van Vleet Thomas M. , Robertson Lynn C.
Published: July 2006

Recent studies indicate that auditory tone presentation and auditory alerting can temporarily ameliorate visuospatial attention deficits in patients with unilateral neglect [Frassinetti, F., Pavani, F., & Ladavas, E. Acoustical vision of neglected stimuli: Interaction among spatially converging audiovisual inputs in neglect patients. Journal of Cognitive Neuroscience, 14, 62–69, 2002; Robertson, I. H., Mattingley, J. B., Rorden, C., & Driver, J. Phasic alerting of neglect patients overcomes their spatial deficit in visual awareness. Nature, 395, 169–172, 1998]. The current study investigated proposed mechanisms of cross-modal interaction to determine conditions in which auditory stimulation affects spatial and nonspatially lateralized attention deficits in a patient with hemispatial neglect. In Experiment 1, a target was presented among related distracters (conjunction search) while a tone was presented either bilaterally or in a congruent or incongruent spatial location with respect to the visual target. Whereas the results suggest a benefit of both general alerting and cross-modal spatial integration on visual search efficiency, the most significant improvement occurred when the target and tone were both presented in contralesional space. In Experiment 2, the effect of auditory alerting on selective attention was examined in a rapid serial visual search procedure with visual targets embedded in a stream of distracters presented at central fixation. When two targets were presented without an alerting tone, the patient missed the second target for up to 1000 msec after the first target appeared (a finding known as the “attentional blink” [AB] and, on average, about 400–500 msec in normals). An alerting tone presented at a fixed temporal location significantly reduced the AB in a tone-duration-dependent manner. Experiment 3 examined the effect of cross-modal space on selective attention in an AB paradigm in which T2 occurred randomly to the left or right of T1 with a spatially congruent or incongruent tone. Discrimination of T2 in contralesional space significantly improved when the tone was presented in the same location, and was impaired when the tone was presented on the ipsilesional side. The findings are discussed as they relate to cross-modal interactions and their influence on spatial and nonspatially lateralized attention deficits in neglect.
Processing the Trees and the Forest during Initial Stages of Face Perception: Electrophysiological Evidence
Authors: Bentin Shlomo , Golland Yulia , Flevaris Anastasia , Robertson Lynn C. , Moscovitch Morris
Published: July 2006

Although configural processing is considered a hallmark of normal face perception in humans, there is ample evidence that processing face components also contributes to face recognition and identification. Indeed, most contemporary models posit a dual-code view in which face identification relies on the analysis of individual face components as well as the spatial relations between them. We explored the interplay between processing face configurations and inner face components by recording the N170, an event-related potential component that manifests early detection of faces. In contrast to a robust N170 effect elicited by line-drawn schematic faces compared to line-drawn schematic objects, no N170 effect was found if a pair of small objects substituted for the eyes in schematic faces. However, if a pair of two miniaturized faces substituted for the eyes, the N170 effect was restored. Additional experiments ruled out an explanation on the basis of miniaturized faces attracting attention independent of their location in a face-like configuration and show that global and local face characteristics compete for processing resources when in conflict. The results are discussed as they relate to normal and abnormal face processing.
Impact of Cloud Model Microphysics on Passive Microwave Retrievals of Cloud Properties. Part I: Model Comparison Using EOF Analyses
Authors: Biggerstaff Michael I. , Seo Eun-Kyoung , Hristova-Veleva Svetla M. , Kim Kwang-Yul
Published: July 2006

The impact of model microphysics on the relationships among hydrometeor profiles, latent heating, and derived satellite microwave brightness temperatures TB have been examined using a nonhydrostatic, adaptive-grid cloud model to simulate a mesoscale convective system over water. Two microphysical schemes (each employing three-ice bulk parameterizations) were tested for two different assumptions in the number of ice crystals assumed to be activated at 0°C to produce simulations with differing amounts of supercooled cloud water. The model output was examined using empirical orthogonal function (EOF) analysis, which provided a quantitative framework in which to compare the simulations. Differences in the structure of the vertical anomaly patterns were related to physical processes and attributed to different approaches in cloud microphysical parameterizations in the two schemes. Correlations between the first EOF coefficients of cloud properties and TB at frequencies associated with the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) showed additional differences between the two parameterization schemes that affected the relationship between hydrometeors and TB. Classified in terms of TB, the microphysical schemes produced significantly different mean vertical profiles of cloud water, cloud ice, snow, vertical velocity, and latent heating. The impact of supercooled cloud water on the 85-GHz TB led to a 15% variation in mean convective rain mass at the surface. The variability in mean profiles produced by the four simulations indicates that the retrievals of cloud properties, especially latent heating, based on TMI frequencies are dependent on the particular microphysical parameterizations used to construct the retrieval database.
The Asymmetry Parameter of Cirrus Clouds Composed of Hollow Bullet Rosette–Shaped Ice Crystals from Ray-Tracing Calculations
Authors: Schmitt C. G. , Iaquinta J. , Heymsfield A. J.
Published: July 2006

Cirrus clouds in the midlatitude and Arctic regions are often composed of bullet rosette–shaped ice crystals. Bullet rosette–shaped ice crystals are composed of a number of bullets radiating from a central point. The bullets that make up the rosette will grow to be hollow in some conditions. To understand better the radiative impact of cirrus clouds, the authors have used a ray-tracing code to calculate the scattering properties of solid and hollow bullet rosettes at visible wavelengths. Results show that hollow bullet rosettes exhibit a broader forward-scattering peak than do solid bullet rosettes. This difference results in an asymmetry parameter that is as much as 0.08 lower for hollow bullet rosettes than for solid rosettes. The effective asymmetry parameter of spheres with the same particle volume and total surface area of the bullet rosettes has also been calculated. Asymmetry parameter estimates for equivalent spheres were similar to those calculated using the ray tracing. Asymmetry parameter calculations were used in combination with direct aircraft measurements from the Atmospheric Radiation Measurement Program intensive operational period in March of 2000. Asymmetry parameter estimates were used with particle size distributions for three cirrus cloud flights for which the observed large particles were predominantly bullet rosettes. Calculated asymmetry parameter values (0.80–0.84) agreed poorly with published cirrus parameterizations (0.75–0.84) when applied to the same aircraft data. Differences lead to 4.5–9 W m−2 differences in reflected and transmitted visible light energy for a cloud of 0.5 optical depth.
Return Levels of Northern Great Plains Snow Water Equivalents
Authors: Grundstein Andrew J. , Lu Qi Qi , Lund Robert
Published: July 2006

This paper estimates return levels of extreme snow water equivalents (SWE) in the northern Great Plains region, containing North and South Dakota, Iowa, Minnesota, and Nebraska. The return levels are estimated from extreme-value methods using a new hybrid SWE dataset that improves the spatial resolution of existing data in the area. A novel aspect of the methods is the use of standard error margins to spatially smooth the estimated SWE return levels computed on individual grid cells. The end product is a reliable return-level estimate that controls for uncertainties in the raw observations. The methods should prove useful in analyses of other geographical regions.
How to Surf
Authors: Evers Clifton
Published: July 2006

This article explores the sensual world of men who surf. Self-reflexive and fictocritical in tone, it meditates on how many studies of masculinity tend to separate the social and bodily. The article maps a way to pull bodies and feelings back into such studies in a productive manner. Affect theory is used to evidence how doing masculinity is built on feelings and intimacy. In turn, the article grounds gender in the activities of everyday life that function to bring together the sociological, psychological, and biological. Furthermore, the article argues that by researching through bodies, it is possible to complicate traditional tropes of masculinity that position it as stable and unemotional. Most important, the researcher's body is shown to be integral to any imagination of how the surfing culture works.
Prevalence of Male Intimate Partner Abuse in Vietnam
Authors: Nguyen Tuyen D.
Published: July 2006

The present study investigated the prevalence of both current and lifetime physical partner abuse among Vietnamese males who reside in Vietnam. Participants ( N = 315) were randomly selected to participate in the study. Participants completed the Vietnamese version of the Conflict Tactics Scale–2. A total of 47% ( n = 148) of the sampled participants were identified as current physical abusers and 68% ( n = 214) as past abusers. Four of the most common abusive tactics abusers exhibited toward their partner were (a) throwing something at their wife (80%), (b) pushing or shoving their partner (78%), (c) beating up their partner (54%), and (d) twisting their partner's arm or hair (60%).
Hostile Sexism, Type of Rape, and Self-Reported Rape Proclivity Within a Sample of Zimbabwean Males
Authors: Viki G. Tendayi , Chiroro Patrick , Abrams Dominic
Published: July 2006

The role of hostile sexism in accounting for rape proclivity among men was investigated using a sample of Zimbabwean students. Participants were presented with either an acquaintance rape or a stranger rape scenario and asked to respond to five questions about the scenario designed to assess rape proclivity. As expected, a significant relationship between hostile sexism and rape proclivity was obtained in the acquaintance rape but not the stranger rape condition. These results replicate previous research and suggest that hostile sexists are more likely to express their hostility toward women in situations where such behavior might be perceived as acceptable.
Communication, Coherence, and Collective Action
Authors: Comfort Louise K. , Haase Thomas W.
Published: July 2006

Communications infrastructure is critical to managing the complex, dynamic operations that evolve in disaster environments. The impact of Hurricane Katrina destroyed the communications infrastructure within the New Orleans metropolitan region, leaving emergency response personnel and the public with little capacity to exchange information vital for coordinating response actions. The loss of communications proved especially damaging, given the size of the geographic region and the number of people affected. The authors used content analysis of news reports to identify the network of organizations that emerged in response to Hurricane Katrina, and network analysis to examine patterns of interaction among the organizations. The patterns reveal significant asymmetry in information among organizations at different levels of authority and responsibility in the disaster response system, a condition that contributed to the collapse of coordination in disaster operations. Conversely, well-designed communications and information infrastructure can contribute significantly to the resilience of communities exposed to recurring risk.
Restricted Play
Authors: Brookey Robert Alan , Booth Paul
Published: July 2006

Although recent critical studies have begun to acknowledge the aesthetic connections that films and video games share, too often these studies neglect to extend an analysis to consumer culture. As video games now make up an important segment of the film industry’s market, this critical engagement is needed to extend the scholarship on video games. Specifically, this essay critically engages the concept of interactivity as an important theoretical construction in the study of video games. Through an analysis of The Lord of the Rings: The Return of the King video game, the authors discover that interactivity can be limited in a way that augments the synergistic connections between films and video games.
Hybrid Reality Games Reframed
Authors: de Souza e Silva Adriana , Delacruz Girlie C.
Published: July 2006

Hybrid reality games (HRGs) employ mobile technologies and GPS devices as tools for transforming physical spaces into interactive game boards. Rather than situating participants in simulated environments, which mimic the physical world, HRGs make use of physical world immersion by merging physical and digital spaces. Online multiuser environments already connect users who do not share contiguous spaces. With mobile devices, players may additionally incorporate interactions with the surrounding physical space. This article is a speculative study about the potential uses of HRGs in education, as activities responsible for taking learning practices outside the closed classroom environment into open, public spaces. Adopting the framework of sociocultural learning theory, the authors analyze design elements of existing HRGs, such as mobility and location awareness, collaboration/sociability, and the configuration of the game space, with the aim of reframing these games into an educational context to foresee how future games might contribute to discovery and learning.
Dissociation of local nitric oxide concentration and vasoconstriction in the presence of cell-free hemoglobin oxygen carriers
Authors: Tsai Amy G. , Cabrales Pedro , Manjula Belur N. , Acharya Seetharama A. , Winslow Robert M. , Intaglietta Marcos
Published: July 2006

Cell-free hemoglobin's (CFH) high affinity for nitric oxide (NO) could limit CFH's use as an oxygen-carrying blood replacement fluid because it scavenges NO, causing vasoconstriction and hypertension. However, the extent to which perivascular NO levels change following intravascular administration of hemoglobin (Hb) with different molecular dimensions correlates with vasoconstrictive responses in the microcirculation is unknown. The study objective was to determine vasoconstrictive effects following bolus infusions of (1) αα cross-linked Hb; (2) polymerized bovine Hb; or (3) polyethylene glycol-decorated Hb (PEG-Hb), by measurements of in vivo microvessel diameter, blood flow, perivascular NO concentration, and systemic hemodynamic parameters. All CFHs caused reductions in perivascular NO levels, not correlated to microvascular responses. PEG-Hb (largest molecular volume) maintained blood flow, while the others caused vasoconstriction and reduced perfusion. All solutions increased mean arterial pressure due to vasoconstriction and blood volume expansion, except for PEG-Hb, which increased blood pressure due to blood volume expansion and maintenance of cardiac output. In conclusion, perivascular NO reduction is similar for all Hb solutions because NO binding affinities are similar; however, effects on vascular resistance are related to the type of molecular modification, molecular volume, and oxygen affinity.
The role of sialomucin CD164 (MGC-24v or endolyn) in prostate cancer metastasis
Authors: Havens AM , Jung Y , Sun YX , Wang J , Shah RB , Bühring HJ , Pienta KJ , Taichman RS
Published: July 2006

Background

The chemokine stromal derived factor-1 (SDF-1 or CXCL12) and its receptor CXCR4 have been demonstrated to be crucial for the homing of stem cells and prostate cancers to the marrow. While screening prostate cancers for CXCL12-responsive adhesion molecules, we identified CD164 (MGC-24) as a potential regulator of homing. CD164 is known to function as a receptor that regulates stem cell localization to the bone marrow.

Results

Using prostate cancer cell lines, it was demonstrated that CXCL12 induced both the expression of CD164 mRNA and protein. Functional studies demonstrated that blocking CD164 on prostate cancer cell lines reduced the ability of these cells to adhere to human bone marrow endothelial cells, and invade into extracellular matrices. Human tissue microarrays stained for CD164 demonstrated a positive correlation with prostate-specific antigen levels, while its expression was negatively correlated with the expression of androgen receptor.

Conclusion

Our findings suggest that CD164 may participate in the localization of prostate cancer cells to the marrow and is further evidence that tumor metastasis and hematopoietic stem cell trafficking may involve similar processes.
Metabolic engineering of microbes for oligosaccharide and polysaccharide synthesis
Authors: Ruffing Anne , Chen Rachel Ruizhen
Published: July 2006

Metabolic engineering has recently been embraced as an effective tool for developing whole-cell biocatalysts for oligosaccharide and polysaccharide synthesis. Microbial catalysts now provide a practical means to derive many valuable oligosaccharides, previously inaccessible through other methods, in sufficient quantities to support research and clinical applications. The synthesis process based upon these microbes is scalable as it avoids expensive starting materials. Most impressive is the high product concentrations (up to 188 g/L) achieved through microbe-catalyzed synthesis. The overall cost for selected molecules has been brought to a reasonable range (estimated $ 30–50/g).

Microbial synthesis of oligosaccharides and polysaccharides is a carbon-intensive and energy-intensive process, presenting some unique challenges in metabolic engineering. Unlike nicotinamide cofactors, the required sugar nucleotides are products of multiple interacting pathways, adding significant complexity to the metabolic engineering effort. Besides the challenge of providing the necessary mammalian-originated glycosyltransferases in active form, an adequate uptake of sugar acceptors can be an issue when another sugar is necessary as a carbon and energy source. These challenges are analyzed, and various strategies used to overcome these difficulties are reviewed in this article. Despite the impressive success of the microbial coupling strategy, there is a need to develop a single strain that can achieve at least the same efficiency. Host selection and the manner with which the synthesis interacts with the central metabolism are two important factors in the design of microbial catalysts. Additionally, unlike in vitro enzymatic synthesis, product degradation and byproduct formation are challenges of whole-cell systems that require additional engineering. A systematic approach that accounts for various and often conflicting requirements of the synthesis holds the key to deriving an efficient catalyst.

Metabolic engineering strategies applied to selected polysaccharides (hyaluronan, alginate, and exopolysaccharides for food use) are reviewed in this article to highlight the recent progress in this area and similarity to challenges in oligosaccharide synthesis. Many naturally occurring microbes possess highly efficient mechanisms for polysaccharide synthesis. These mechanisms could potentially be engineered into a microbe for oligosaccharide and polysaccharide synthesis with enhanced efficiency.
Expansion of opiate agonist treatment: an historical perspective
Authors: Newman Robert G
Published: July 2006

Untreated opiate addiction remains a major health care crisis in New York and in most other urban centers in America. Optimism for closing the gap between need and demand for treatment and its availability has greeted the recent approval of a new opiate medication for addiction, buprenorphine – which unlike methadone may be prescribed by independent, office-based practitioners. The likelihood of buprenorphine fulfilling its potential is assessed in the light of the massive expansion of methadone treatment more than 30 years earlier. It is concluded that the key, indispensable ingredient of success will be true commitment on the part of Government to provide care to all those who need it.
Simvastatin inhibits interferon-γ-induced MHC class II up-regulation in cultured astrocytes
Authors: Zeinstra Esther , Wilczak Nadine , Chesik Daniel , Glazenburg Lisa , Kroese Frans GM , De Keyser Jacques
Published: July 2006

Based on their potent anti-inflammatory properties and a preliminary clinical trial, statins (HMG-CoA reductase inhibitors) are being studied as possible candidates for multiple sclerosis (MS) therapy. The pathogenesis of MS is unclear. One theory suggests that the development of autoimmune lesions in the central nervous system may be due to a failure of endogenous inhibitory control of MHC class II expression on astrocytes, allowing these cells to adapt an interferon (IFN)-γ-induced antigen presenting phenotype. By using immunocytochemistry in cultured astrocytes derived from newborn Wistar rats we found that simvastatin at nanomolar concentrations inhibited, in a dose-response fashion, up to 70% of IFN-γ-induced MHC class II expression. This effect was reversed by the HMG-CoA reductase product mevalonate. Suppression of the antigen presenting function of astrocytes might contribute to the beneficial effects of statins in MS.
Postictal psychosis: presymptomatic risk factors and the need for further investigation of genetics and pharmacotherapy
Authors: Morrow Eric M , Lafayette Jennifer M , Bromfield Edward B , Fricchione Gregory
Published: July 2006

Background

Postictal psychosis (PIP), an episode of psychosis occurring after a cluster of seizures, is common and may be associated with profound morbidity, including chronic psychosis. Symptoms are often pleomorphic, involving a range of psychotic symptoms, including hallucinations and disorders of thought. PIP is treatable and may be averted if presymptomatic risk factors are considered in susceptible patients and treatment is initiated.

Case presentation

In this report, we present an illustrative case of PIP. The patient, Mr. R, presented to our emergency room with delusions and disordered thought process following a cluster of seizures. He recovered after admission, sedation and treatment with antipsychotic medication.

Discussion

A list of presymptomatic risk factors is established based on review of current literature. Identification of such risk factors may potentially help with prophylactic treatment; however, little empirical research exists in this area and treatment guidelines are thus far largely based on expert opinion. Further, while the neurobiology of schizophrenia is advancing at a rapid pace, largely due to advances in genetics, the pathophysiology of PIP remains largely unknown. Considering the progress in schizophrenia research in the context of the clinical features of PIP and existing studies, potential neurobiological mechanisms for PIP are herein proposed, and further genetic analyses, which may help identify those susceptible, are warranted.

Conclusion

While PIP is an important problem that may present first to general hospital psychiatrists, as in the case presented, this topic is under-represented in the medical psychiatry literature. As discussed in this article, further research is needed to develop presymptomatic screens and treatment pathways to help prevent morbidity.
Inhibition of anti-tuberculosis T-lymphocyte function with tumour necrosis factor antagonists
Authors: Hamdi Haïfa , Mariette Xavier , Godot Véronique , Weldingh Karin , Hamid Abdul Monem , Prejean Maria-Victoria , Baron Gabriel , Lemann Marc , Puechal Xavier , Breban Maxime , Berenbaum Francis , Delchier Jean-Charles , Flipo René-Marc , Dautzenberg Bertrand , Salmon Dominique , Humbert Marc , Emilie Dominique ,   the RATIO (Recherche sur Anti-TNF et Infections Opportunistes) Study Group
Published: July 2006

Reactivation of latent Mycobacterium tuberculosis (Mtb) infection is a major complication of anti-tumour necrosis factor (TNF)-α treatment, but its mechanism is not fully understood. We evaluated the effect of the TNF antagonists infliximab (Ifx), adalimumab (Ada) and etanercept (Eta) on anti-mycobacterial immune responses in two conditions: with ex vivo studies from patients treated with TNF antagonists and with the in vitro addition of TNF antagonists to cells stimulated with mycobacterial antigens. In both cases, we analysed the response of CD4+ T lymphocytes to purified protein derivative (PPD) and to culture filtrate protein (CFP)-10, an antigen restricted to Mtb. The tests performed were lymphoproliferation and immediate production of interferon (IFN)-γ. In the 68 patients with inflammatory diseases (rheumatoid arthritis, spondylarthropathy or Crohn's disease), including 31 patients with a previous or latent tuberculosis (TB), 14 weeks of anti-TNF-α treatment had no effect on the proliferation of CD4+ T lymphocytes. In contrast, the number of IFN-γ-releasing CD4+ T lymphocytes decreased for PPD (p < 0.005) and CFP-10 (p < 0.01) in patients with previous TB and for PPD (p < 0.05) in other patients (all vaccinated with Bacille Calmette-Guérin). Treatments with Ifx and with Eta affected IFN-γ release to a similar extent. In vitro addition of TNF antagonists to CD4+ T lymphocytes stimulated with mycobacterial antigens inhibited their proliferation and their expression of membrane-bound TNF (mTNF). These effects occurred late in cultures, suggesting a direct effect of TNF antagonists on activated mTNF+ CD4+ T lymphocytes, and Ifx and Ada were more efficient than Eta. Therefore, TNF antagonists have a dual action on anti-mycobacterial CD4+ T lymphocytes. Administered in vivo, they decrease the frequency of the subpopulation of memory CD4+ T lymphocytes rapidly releasing IFN-γ upon challenge with mycobacterial antigens. Added in vitro, they inhibit the activation of CD4+ T lymphocytes by mycobacterial antigens. Such a dual effect may explain the increased incidence of TB in patients treated with TNF antagonists as well as possible differences between TNF antagonists for the incidence and the clinical presentation of TB reactivation.
A model of anti-angiogenesis: differential transcriptosome profiling of microvascular endothelial cells from diffuse systemic sclerosis patients
Authors: Giusti Betti , Fibbi Gabriella , Margheri Francesca , Serratì Simona , Rossi Luciana , Poggi Filippo , Lapini Ilaria , Magi Alberto , Del Rosso Angela , Cinelli Marina , Guiducci Serena , Kahaleh Bashar , Bazzichi Laura , Bombardieri Stefano , Matucci-Cerinic Marco , Gensini Gian Franco , Del Rosso Mario , Abbate Rosanna
Published: July 2006

The objective of this work was to identify genes involved in impaired angiogenesis by comparing the transcriptosomes of microvascular endothelial cells from normal subjects and patients affected by systemic sclerosis (SSc), as a unique human model disease characterized by insufficient angiogenesis. Total RNAs, prepared from skin endothelial cells of clinically healthy subjects and SSc patients affected by the diffuse form of the disease, were pooled, labeled with fluorochromes, and hybridized to 14,000 70 mer oligonucleotide microarrays. Genes were analyzed based on gene expression levels and categorized into different functional groups based on the description of the Gene Ontology (GO) consortium to identify statistically significant terms. Quantitative PCR was used to validate the array results. After data processing and application of the filtering criteria, the analyzable features numbered 6,724. About 3% of analyzable transcripts (199) were differentially expressed, 141 more abundantly and 58 less abundantly in SSc endothelial cells. Surprisingly, SSc endothelial cells over-express pro-angiogenic transcripts, but also show up-regulation of genes exerting a powerful negative control, and down-regulation of genes critical to cell migration and extracellular matrix-cytoskeleton coupling, all alterations that provide an impediment to correct angiogenesis. We also identified transcripts controlling haemostasis, inflammation, stimulus transduction, transcription, protein synthesis, and genome organization. An up-regulation of transcripts related to protein degradation and ubiquitination was observed in SSc endothelial cells. We have validated data on the main anti-angiogenesis-related genes by RT-PCR, western blotting, in vitro angiogenesis and immunohistochemistry. These observations indicate that microvascular endothelial cells of patients with SSc show abnormalities in a variety of genes that are able to account for defective angiogenesis.