bluuebunny/crossref_metadata_2025 huggingface dataset:
Fis1 acts as a mitochondrial recruitment factor for TBC1D15 that is involved in regulation of mitochondrial morphology
Authors: Onoue Kenta , Jofuku Akihiro , Ban-Ishihara Reiko , Ishihara Takaya , Maeda Maki , Koshiba Takumi , Itoh Takashi , Fukuda Mitsunori , Otera Hidenori , Oka Toshihiko , Takano Hiroyoshi , Mizushima Noboru , Mihara Katsuyoshi , Ishihara Naotada
Published: October 2012

In yeast, C-tail-anchored mitochondrial outer membrane protein Fis1 recruits the mitochondrial-fission-regulating GTPase Dnm1 to mitochondrial fission sites. However, the function of its mammalian homologue remains enigmatic because it has been reported to be dispensable for the mitochondrial recruitment of Drp1, a mammalian homologue of Dnm1. We identified TBC1D15 as a Fis1-binding protein in HeLa cell extracts. Immunoprecipitation revealed that Fis1 efficiently interacts with TBC1D15 but not with Drp1. Bacterially expressed Fis1 and TBC1D15 formed a direct and stable complex. Exogenously expressed TBC1D15 localized mainly in cytoplasm in HeLa cells, but when coexpressed with Fis1 it localized to mitochondria. Knockdown of TBC1D15 induced highly developed mitochondrial network structures similar to the effect of Fis1 knockdown, suggesting that the TBC1D15 and Fis1 are associated with the regulation of mitochondrial morphology independently of Drp1. These data suggest that Fis1 acts as a mitochondrial receptor in the recruitment of mitochondrial morphology protein in mammalian cells.
Species-specific recognition of the carrier insect by dauer larvae of the nematode Caenorhabditis japonica
Authors: Okumura Etsuko , Tanaka Ryusei , Yoshiga Toyoshi
Published: October 2012

Host recognition is critical during the phoretic stage of nematodes because it facilitates their association with hosts. However, limited information is available on the direct cues used for host recognition and host specificity in nematodes. Caenorhabditis japonica forms an intimate association with the burrower bug Parastrachia japonensis. C. japonica dauer larvae (DL), the phoretic stage of the nematode, are mainly found on adult P. japonensis female but no other species. To understand the mechanisms of species-specific and female carrier-biased ectophoresy in C. japonica, we investigated whether C. japonica DL could recognize their hosts using nematode loading and chemoattraction experiments. During the loading experiments, up to 300 C. japonica DL embarked on male and female P. japonensis, whereas none or very few utilized the other shield bugs Erthesina fullo and Macroscytus japonensis or the terrestrial isopod Armadillidium vulgare. In the chemoattraction experiments, hexane extracts containing the body surface components of nymphs and both adult P. japonensis sexes attracted C. japonica DL, whereas those of other shield bugs did not. P. japonensis extracts also arrested the dispersal of C. japonica DL released in a site where hexane extracts were spotted on an agar plate; i.e. >50% of DL remained at the site even 60 min after nematode inoculation whereas M. japonensis extracts or hexane alone did not have the same effect. These results suggest that C. japonica DL recognize their host species using direct chemical attractants from their specific host to maintain their association.
ACTH-stimulated cortisol release from head kidney of rainbow trout is modulated by glucose concentration
Authors: Conde-Sieira Marta , Alvarez Rosa , López-Patiño Marcos A. , Míguez Jesús M. , Flik Gert , Soengas José L.
Published: October 2012

To assess the hypothesis of cortisol release in rainbow trout being modulated by glucose levels, we first evaluated cortisol release (basal and ACTH-regulated) by head kidney tissue superfused with medium reflecting hypo-, normo- or hyperglycaemic conditions. Next, cortisol release from head kidney fragments in static incubations was assessed in parallel with changes in parameters related to cortisol synthesis (mRNA abundance of StAR, P450scc, 3βHSD, and 11βH) and the GK-mediated glucosensing mechanism (levels of glycogen and glucose, activities of GK, GSase, and PK, and mRNA levels of GK, GLUT-2, Kir6.x-like, and SUR-like). We then evaluated the effects of two inhibitors of glucose transport cytochalasin B and phlorizin on cortisol production and glucosensing mechanisms. The ACTH-induced release of cortisol proved to be modulated by medium glucose concentration in a way that increased release occurs under high glucose levels, and decreased ACTH-stimulated cortisol release occurs when glucose transport was inhibited by cytochalasin B. The release of cortisol can be associated with increased synthesis since enhanced mRNA abundance of genes related to cortisol synthesis was also noted in high glucose medium. Specific GK-immunoreactivity in the cortisol producing cells (not in chromaffin cells) further substantiates GK-mediated glucosensing in cortisol production. In contrast, no changes compatible with those of glucose levels and cortisol release/synthesis in the presence of ACTH were noted for any other putative glucosensor mechanisms based on LXR, SGLT-1 or Gnat3. The results combined are the first evidence for a mechanism in fish linking synthesis and release of a non-pancreatic hormone like cortisol with circulating glucose levels. The relationship was evident for the regulated (ACTH-dependent) pathway and this suggests that under acute stress conditions glucose is important for the regulation of cortisol synthesis and release
Phylogeny: The science and underlying data
Authors: Wortley Alexandra H.
Published: October 2012

This article explains the nature of some of the phylogenetic data underlying a 2010 ‘Phylogeny Weekend’ from the viewpoint of a scientist. Phylogenies are a way of visualising inferred evolutionary relationships between organisms, making them intelligible and useful. They
may be based upon morphological or genetic data, and are constructed through a series of steps, outlined below, and reliant upon a series of assumptions. I describe how phylogenies are used in my work, to interpret the evolution of plant characters such as the nature of pollen grains. I also
explain how the guided walk, Plant Routes, was developed to provide an interactive exploration of phylogeny at the Royal Botanic Garden Edinburgh.
Reviews
Authors: Vinuela-Fernandez Ignacio , Speed Chris , Coulton Paul
Published: October 2012

SKYLANDERS: NEAR FIELD IN YOUR LIVING ROOM NOW
Force/Magnitude workshop
Authors: Andruszkiewicz Jan , Thomas Paul
Published: October 2012

The short paper plots the inclusion of an art workshop within the realm of the nanotechnological laboratory. The history given to us by Robert Hooke in his book Micrographia, reveals a symbiotic relationship between art and science through the drawings created from his enhanced perceptions
through the microscope. This history is re-embedded in the present tense with evidence of the research produced by artists engaged in Force/Magnitude workshop exploring the contemporary imaging via the atomic force microscope.
The Soluble Isoform of CX3CL1 Is Necessary for Neuroprotection in a Mouse Model of Parkinson's Disease
Authors: Morganti Josh M. , Nash Kevin R. , Grimmig Bethany A. , Ranjit Sonali , Small Brent , Bickford Paula C. , Gemma Carmelina
Published: October 2012

The chemokine CX3CL1/fractalkine is expressed by neurons as a transmembrane-anchored protein that can be cleaved to yield a soluble isoform. However, the roles for these two types of endogenous CX3CL1 in neurodegenerative pathophysiology remain elusive. As such, it has been difficult to delineate the function of the two isoforms of CX3CL1, as both are natively present in the brain. In this study we examined each isoform's ability to regulate neuroinflammation in a mouse model of Parkinson's disease initiated by the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). We were able to delineate the function of both CX3CL1 isoforms by using adeno-associated virus-mediated gene therapy to selectively express synthetic variants of CX3CL1 that remain either permanently soluble or membrane bound. In the present study we injected each CX3CL1 variant or a GFP-expressing vector directly into the substantia nigra ofCX3CL1−/−mice. Our results show that only the soluble isoform of CX3CL1 is sufficient for neuroprotection after exposure to MPTP. Specifically, we show that the soluble CX3CL1 isoform reduces impairment of motor coordination, decreases dopaminergic neuron loss, and ameliorates microglial activation and proinflammatory cytokine release resulting from MPTP exposure. Furthermore, we show that the membrane-bound isoform provides no neuroprotective capability to MPTP-induced pathologies, exhibiting similar motor coordination impairment, dopaminergic neuron loss, and inflammatory phenotypes as MPTP-treatedCX3CL1−/−mice, which received the GFP-expressing control vector. Our results reveal that the neuroprotective capacity of CX3CL1 resides solely upon the soluble isoform in an MPTP-induced model of Parkinson's disease.
Beneficial Effects of αB-Crystallin in Spinal Cord Contusion Injury
Authors: Klopstein Armelle , Santos-Nogueira Eva , Francos-Quijorna Isaac , Redensek Adriana , David Samuel , Navarro Xavier , López-Vales Rubèn
Published: October 2012

αB-crystallin is a member of the heat shock protein family that exerts cell protection under several stress-related conditions. Recent studies have revealed that αB-crystallin plays a beneficial role in a mouse model of multiple sclerosis, brain ischemia, and Alexander disease. Whether αB-crystallin plays a role in modulating the secondary damage after CNS trauma is not known. We report here that αB-crystallin mediates protective effects after spinal cord injury. The levels of αB-crystallin are reduced in spinal cord tissue following contusion lesion. In addition, administration of recombinant human αB-crystallin for the first week after contusion injury leads to sustained improvement in locomotor skills and amelioration of secondary tissue damage. We also provide evidence that recombinant human αB-crystallin modulates the inflammatory response in the injured spinal cord, leading to increased infiltration of granulocytes and reduced recruitment of inflammatory macrophages. Furthermore, the delivery of recombinant human αB-crystallin promotes greater locomotor recovery even when the treatment is initiated 6 h after spinal cord injury. Our findings suggest that administration of recombinant human αB-crystallin may be a good therapeutic approach for treating acute spinal cord injury, for which there is currently no effective treatment.
Label-Free Imaging of Cerebral β-Amyloidosis with Extended-Focus Optical Coherence Microscopy
Authors: Bolmont Tristan , Bouwens Arno , Pache Christophe , Dimitrov Mitko , Berclaz Corinne , Villiger Martin , Wegenast-Braun Bettina M. , Lasser Theo , Fraering Patrick C.
Published: October 2012

We demonstrate label-free imaging of cerebral β-amyloidosisex vivoand in a living mouse model of Alzheimer's disease using extended-focus Fourier domain optical coherence microscopy (xfOCM). xfOCM provides 3D, high-resolution images of individual β-amyloid plaques in the brain parenchyma and vasculature and requires no staining of the Alzheimeric sample under investigation. xfOCM also opens the possibility to perform minimally invasive studies of β-amyloid pathologyin vivo, without the use of labeling methods, which potentially confound experimental findings.
Genome-Wide Linkage Analysis of Human Auditory Cortical Activation Suggests Distinct Loci on Chromosomes 2, 3, and 8
Authors: Renvall Hanna , Salmela Elina , Vihla Minna , Illman Mia , Leinonen Eira , Kere Juha , Salmelin Riitta
Published: October 2012

Neural processes are explored through macroscopic neuroimaging and microscopic molecular measures, but the two levels remain primarily detached. The identification of direct links between the levels would facilitate use of imaging signals as probes of genetic function and, vice versa, access to molecular correlates of imaging measures. Neuroimaging patterns have been mapped for a few isolated genes, chosen based on their connection with a clinical disorder. Here we propose an approach that allows an unrestricted discovery of the genetic basis of a neuroimaging phenotype in the normal human brain. The essential components are a subject population that is composed of relatives and selection of a neuroimaging phenotype that is reproducible within an individual and similar between relatives but markedly variable across a population. Our present combined magnetoencephalography and genome-wide linkage study in 212 healthy siblings demonstrates that auditory cortical activation strength is highly heritable and, specifically in the right hemisphere, regulated oligogenically with linkages to chromosomes 2q37, 3p12, and 8q24. The identified regions delimit as candidate genesTRAPPC9, operating in neuronal differentiation, andROBO1, regulating projections of thalamocortical axons. Identification of normal genetic variation underlying neurophysiological phenotypes offers a non-invasive platform for an in-depth, concerted capitalization of molecular and neuroimaging levels in exploring neural function.
TRIP8b-Independent Trafficking and Plasticity of Adult Cortical Presynaptic HCN1 Channels
Authors: Huang Zhuo , Lujan Rafael , Martinez-Hernandez Jose , Lewis Alan S. , Chetkovich Dane M. , Shah Mala M.
Published: October 2012

Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are subthreshold activated voltage-gated ion channels. In the cortex, these channels are predominantly expressed in dendrites where they significantly modify dendritic intrinsic excitability as well synaptic potential shapes and integration. HCN channel trafficking to dendrites is regulated by the protein, TRIP8b. Additionally, altered TRIP8b expression may be one mechanism underlying seizure-induced dendritic HCN channel plasticity. HCN channels, though, are also located in certain mature cortical synaptic terminals, where they play a vital role in modulating synaptic transmission. In this study, using electrophysiological recordings as well as electron microscopy we show that presynaptic, but not dendritic, cortical HCN channel expression and function is comparable in adult TRIP8b-null mice and wild-type littermates. We further investigated whether presynaptic HCN channels undergo seizure-dependent plasticity. We found that, like dendritic channels, wild-type presynaptic HCN channel function was persistently decreased following induction of kainic acid-induced seizures. Since TRIP8b does not affect presynaptic HCN subunit trafficking, seizure-dependent plasticity of these cortical HCN channels is not conditional upon TRIP8b. Our results, thus, suggest that the molecular mechanisms underlying HCN subunit targeting, expression and plasticity in adult neurons is compartment selective, providing a means by which pre- and postsynaptic processes that are critically dependent upon HCN channel function may be distinctly influenced.
Cyclin-Dependent Kinase 5 Controls TRPV1 Membrane Trafficking and the Heat Sensitivity of Nociceptors through KIF13B
Authors: Xing Bao-Ming , Yang Yan-Rui , Du Jun-Xia , Chen Hai-Jing , Qi Cai , Huang Zhi-Hua , Zhang Ying , Wang Yun
Published: October 2012

The number of functional transient receptor potential vanilloid 1 (TRPV1) channels at the surface, especially at the peripheral terminals of primary sensory neurons, regulates heat sensitivity, and increased surface localization of TRPV1s contributes to heat hyperalgesia. However, the mechanisms for regulating TRPV1 surface localization are essentially unknown. Here, we show that cyclin-dependent kinase 5 (Cdk5), a new player in thermal pain sensation, positively regulates TRPV1 surface localization. Active Cdk5 was found to promote TRPV1 anterograde transportin vivo, suggesting a regulatory role of Cdk5 in TRPV1 membrane trafficking. TRPV1-containing vesicles bind to the forkhead-associated (FHA) domain of the KIF13B (kinesin-3 family member 13B) and are thus delivered to the cell surface. Overexpression of Cdk5 or its activator p35 promoted and inhibition of Cdk5 activity prevented the KIF13B–TRPV1 association, indicating that Cdk5 promotes TRPV1 anterograde transport by mediating the motor–cargo association. Cdk5 phosphorylates KIF13B at Thr-506, a residue located in the FHA domain. T506A mutation reduced the motor–cargo interaction and the cell-permeable TAT–T506 peptide, targeting to the Thr-506, decreased TRPV1 surface localization, demonstrating the essential role of Thr-506 phosphorylation in TRPV1 transport. Moreover, complete Freund's adjuvant (CFA) injection-induced activation of Cdk5 increased the anterograde transport of TRPV1s, contributing to the development and possibly the maintenance of heat hyperalgesia, whereas intrathecal delivery of the TAT–T506 peptide alleviated CFA-induced heat hyperalgesia in rats. Thus, Cdk5 regulation of TRPV1 membrane trafficking is a fundamental mechanism controlling the heat sensitivity of nociceptors, and moderate inhibition of Thr-506 phosphorylation during inflammation might be helpful for the treatment of inflammatory thermal pain.
Prefrontally Driven Downregulation of Neural Synchrony Mediates Goal-Directed Forgetting
Authors: Hanslmayr Simon , Volberg Gregor , Wimber Maria , Oehler Nora , Staudigl Tobias , Hartmann Thomas , Raabe Markus , Greenlee Mark W. , Bäuml Karl-Heinz T.
Published: October 2012

Neural synchronization between distant cell assemblies is crucial for the formation of new memories. To date, however, it remains unclear whether higher-order brain regions can adaptively regulate neural synchrony to control memory processing in humans. We explored this question in two experiments using a voluntary forgetting task. In the first experiment, we simultaneously recorded electroencephalography along with fMRI. The results show that a reduction in neural synchrony goes hand-in-hand with a BOLD signal increase in the left dorsolateral prefrontal cortex (dlPFC) when participants are cued to forget previously studied information. In the second experiment, we directly stimulated the left dlPFC with repetitive transcranial magnetic stimulation during the same task, and show that such stimulation specifically boosts the behavioral forgetting effect and induces a reduction in neural synchrony. These results suggest that prefrontally driven downregulation of long-range neural synchronization mediates goal-directed forgetting of long-term memories.
Oligodendrocyte Regeneration after Neonatal Hypoxia Requires FoxO1-Mediated p27Kip1Expression
Authors: Jablonska Beata , Scafidi Joseph , Aguirre Adan , Vaccarino Flora , Nguyen Vien , Borok Erzsebet , Horvath Tamas L. , Rowitch David H. , Gallo Vittorio
Published: October 2012

Diffuse white matter injury (DWMI) caused by hypoxia is associated with permanent neurodevelopmental disabilities in preterm infants. The cellular and molecular mechanisms producing DWMI are poorly defined. Using a mouse model of neonatal hypoxia, we demonstrate a biphasic effect on oligodendrocyte development, resulting in hypomyelination. Oligodendrocyte death and oligodendrocyte progenitor cell (OPC) proliferation during the week after hypoxia were followed by delayed oligodendrocyte differentiation and abnormal myelination, as demonstrated by electron microscopy. Cdk2 activation was essential for the regenerative OPC response after hypoxia and was accompanied by reduced FoxO1-dependent p27Kip1expression. p27Kip1was also reduced in OPCs in human infant white matter lesions after hypoxia. The negative effects of hypoxia on oligodendrogenesis and myelination were more pronounced in p27Kip1-null mice; conversely, overexpression of FoxO1 or p27Kip1in OPCs after hypoxia promoted oligodendrogenesis. Our studies demonstrate for the first time that neonatal hypoxia affects the Foxo1/p27Kip1pathway during white matter development. We also show that molecular manipulation of this pathway enhances oligodendrocyte regeneration during a critical developmental time window after DWMI. Thus, FoxO1 and p27Kip1may serve as promising target molecules for promoting timely oligodendrogenesis in neonatal DWMI.
Intracisternal Interleukin-1 Receptor Antagonist Prevents Postoperative Cognitive Decline and Neuroinflammatory Response in Aged Rats
Authors: Barrientos Ruth M. , Hein Amy M. , Frank Matthew G. , Watkins Linda R. , Maier Steven F.
Published: October 2012

To investigate the role of the pro-inflammatory cytokine interleukin-1β (IL-1β) in postoperative cognitive dysfunction (POCD) in aged rats, we used laparotomy to mimic human abdominal surgery in adult (3 months) and aged (24 months) F344/BN rats. We demonstrated that memory consolidation of the hippocampal-dependent contextual fear-conditioning task is significantly impaired in aged but not young rats 4 d after surgery. Hippocampal-independent auditory-cued fear memory was not disrupted by laparotomy in either age group. The hippocampal-dependent memory impairment was paralleled by elevations of IL-1β in the hippocampus of aged animals 1 and 4 d after surgery. These findings support our substantial line of previous research showing that aged animals are more vulnerable to cognitive decline after a peripheral immune challenge. In addition, we demonstrated that a single intracisternal administration of interleukin-1 receptor antagonist (IL-1RA; 112 μg) at the time of surgery was sufficient to block both the behavioral deficit and the neuroinflammatory response. Injecting the same dose of IL-1RA peripherally failed to have a protective effect. These data provide strong support for the specific role of central, not peripheral, IL-1β in POCD. Furthermore, the long-lasting presence of IL-1RA in the brain (4 d) compared with in the blood (<24 h) underscores the value of intracisternal administration of IL-1RA for therapeutic purposes.
Compartmentalization and Ca2+Buffering Are Essential for Prevention of Light-Induced Retinal Degeneration
Authors: Weiss Shirley , Kohn Elkana , Dadon Daniela , Katz Ben , Peters Maximilian , Lebendiker Mario , Kosloff Mickey , Colley Nansi Jo , Minke Baruch
Published: October 2012

Fly photoreceptors are polarized cells, each of which has an extended interface between its cell body and the light-signaling compartment, the rhabdomere. Upon intense illumination, rhabdomeric calcium concentration reaches millimolar levels that would be toxic if Ca2+diffusion between the rhabdomere and cell body was not robustly attenuated. Yet, it is not clear how such effective attenuation is obtained. Here we show that Ca2+homeostasis in the photoreceptor cell relies on the protein calphotin. This unique protein functions as an immobile Ca2+buffer localized along the base of the rhabdomere, separating the signaling compartment from the cell body. Generation and analyses of transgenicDrosophilastrains, in which calphotin-expression levels were reduced in a graded manner, showed that moderately reduced calphotin expression impaired Ca2+homeostasis while calphotin elimination resulted in severe light-dependent photoreceptor degeneration. Electron microscopy, electrophysiology, and optical methods revealed that the degeneration was rescued by prevention of Ca2+overload via overexpression of CalX, the Na+–Ca2+exchanger. In addition, Ca2+-imaging experiments showed that reduced calphotin levels resulted in abnormally fast kinetics of Ca2+elevation in photoreceptor cells. Together, the data suggest that calphotin functions as a Ca2+buffer; a possibility that we directly demonstrate by expressing calphotin in a heterologous expression system. We propose that calphotin-mediated compartmentalization and Ca2+buffering constitute an effective strategy to protect cells from Ca2+overload and light-induced degeneration.
Target-Specific Suppression of GABA Release from Parvalbumin Interneurons in the Basolateral Amygdala by Dopamine
Authors: Chu Hong-Yuan , Ito Wataru , Li Jiayang , Morozov Alexei
Published: October 2012

Dopamine (DA) in the basolateral amygdala (BLA) promotes fear learning by disinhibiting principal neurons (PNs) and enabling synaptic plasticity in their sensory inputs. While BLA interneurons (INs) are heterogeneous, it is unclear which interneuron subtypes decrease GABAergic input to PNs in the presence of DA. Here, using cell type-selective photostimulation by channelrhodopsin 2 in BLA slices from mouse brain, we examined the role of parvalbumin-positive INs (PV-INs), the major interneuronal subpopulation in BLA, in the disinhibitory effect of DA. We found that DA selectively suppressed GABAergic transmission from PV-INs to PNs by acting on presynaptic D2receptors, and this effect was mimicked by Rp-cAMP, an inhibitor of cAMP-dependent signaling. In contrast, DA did not alter GABA release from PV-INs to INs. Furthermore, neither suppressing cAMP-dependent signaling by Rp-cAMP nor enhancing it by forskolin altered GABA release from PV-INs to BLA INs. Overall, DA disinhibits BLA, at least in part, by suppressing GABA release from PV-INs in the target cell-specific manner that results from differential control of this release by cAMP-dependent signaling.
Serotonin-Induced Cleavage of the Atypical Protein Kinase C Apl III inAplysia
Authors: Bougie Joanna K. , Cai Diancai , Hastings Margaret , Farah Carole A. , Chen Shanping , Fan Xiaotang , McCamphill Patrick K. , Glanzman David L. , Sossin Wayne S.
Published: October 2012

A constitutively active kinase, known as protein kinase Mζ (PKMζ), is proposed to act as a long-lasting molecular memory trace. While PKMζ is formed in rodents through translation of a transcript initiating in an intron of the protein kinase Cζ (PKCζ) gene, this transcript does not exist inAplysia californicadespite the fact that inhibitors of PKMζ erase memory inAplysiain a fashion similar to rodents. We have previously shown that, inAplysia, the ortholog of PKCζ, PKC Apl III, is cleaved by calpain to form a PKM after overexpression of PKC Apl III. We now show that kinase activity is required for this cleavage. We further use a FRET reporter to measure cleavage of PKC Apl III into PKM Apl III in live neurons using a stimulus that induces plasticity. Our results show that a 10 min application of serotonin induces cleavage of PKC Apl III in motor neuron processes in a calpain- and protein synthesis-dependent manner, but does not induce cleavage of PKC Apl III in sensory neuron processes. Furthermore, a dominant-negative PKM Apl III expressed in the motor neuron blocked the late phase of intermediate-term facilitation in sensory-motor neuron cocultures induced by 10 min of serotonin. In summary, we provide evidence that PKC Apl III is cleaved into PKM Apl III during memory formation, that the requirements for cleavage are the same as the requirements for the plasticity, and that PKM in the motor neuron is required for intermediate-term facilitation.
Neural Substrate of the Late Positive Potential in Emotional Processing
Authors: Liu Yuelu , Huang Haiqing , McGinnis-Deweese Menton , Keil Andreas , Ding Mingzhou
Published: October 2012

The late positive potential (LPP) is a reliable electrophysiological index of emotional perception in humans. Despite years of research, the brain structures that contribute to the generation and modulation of LPP are not well understood. Recording EEG and fMRI simultaneously, and applying a recently proposed single-trial ERP analysis method, we addressed the problem by correlating the single-trial LPP amplitude evoked by affective pictures with the blood oxygen level-dependent (BOLD) activity. Three results were found. First, relative to neutral pictures, pleasant and unpleasant pictures elicited enhanced LPP, as well as heightened BOLD activity in both visual cortices and emotion-processing structures such as amygdala and prefrontal cortex, consistent with previous findings. Second, the LPP amplitude across three picture categories was significantly correlated with BOLD activity in visual cortices, temporal cortices, amygdala, orbitofrontal cortex, and insula. Third, within each picture category, LPP–BOLD coupling revealed category-specific differences. For pleasant pictures, the LPP amplitude was coupled with BOLD in occipitotemporal junction, medial prefrontal cortex, amygdala, and precuneus, whereas for unpleasant pictures significant LPP–BOLD correlation was observed in ventrolateral prefrontal cortex, insula, and posterior cingulate cortex. These results suggest that LPP is generated and modulated by an extensive brain network composed of both cortical and subcortical structures associated with visual and emotional processing and the degree of contribution by each of these structures to the LPP modulation is valence specific.
Hippocampal Place Cells Can Encode Multiple Trial-Dependent Features through Rate Remapping
Authors: Allen Kevin , Rawlins J. Nick P. , Bannerman David M. , Csicsvari Jozsef
Published: October 2012

The activity of hippocampal pyramidal cells reflects both the current position of the animal and information related to its current behavior. Here we investigated whether single hippocampal neurons can encode several independent features defining trials during a memory task. We also tested whether task-related information is represented by partial remapping of the place cell population or, instead, via firing rate modulation of spatially stable place cells. To address these two questions, the activity of hippocampal neurons was recorded in rats performing a conditional discrimination task on a modified T-maze in which the identity of a food reward guided behavior. When the rat was on the central arm of the maze, the firing rate of pyramidal cells changed depending on two independent factors: (1) the identity of the food reward given to the animal and (2) the previous location of the animal on the maze. Importantly, some pyramidal cells encoded information relative to both factors. This trial-type specific and retrospective coding did not interfere with the spatial representation of the maze: hippocampal cells had stable place fields and their theta-phase precession profiles were unaltered during the task, indicating that trial-related information was encoded via rate remapping. During error trials, encoding of both trial-related information and spatial location was impaired. Finally, we found that pyramidal cells also encode trial-related information via rate remapping during the continuous version of the rewarded alternation task without delays. These results suggest that hippocampal neurons can encode several task-related cognitive aspects via rate remapping.
Panic’s Castle
Authors: Dolven Jeff
Published: October 2012

“Panic’s Castle” considers panic—self-loss under the threat of self-contradiction—as a perpetual interruption of the action of Spenser’s Faerie Queene and simultaneously as the cause of its organization from the level of the line up to the architecture of the six books. The essay proposes a reading of overcommitment and overcorrection as the fundamental Spenserian dynamic.
The “Sticky Sediment” of Daily Life: Radical Domesticity, Revolutionary Christianity, and the Problem of Wealth in Britain from the 1880s to the 1930s
Authors: Koven Seth
Published: October 2012

This essay examines an early twentieth-century Christian revolutionary habitus—a “technique of Christian living”—based on the conviction that everyday life was an essential site for reconciling the claims of individual and community, the material and the spiritual. The pacifist-feminist members of London’s first “people’s house,” Kingsley Hall, linked their vision of Jesus’s inclusive and unbounded love for humanity to their belief in the ethical imperative that all people take full moral responsibility for cleaning up their own dirt as part of their utopian program to bring social, economic, and political justice to the outcast in London, Britain, and its empire. In imagining what a reconstructed post-World War I Britain might become, Kingsley Hall’s cross-class band of workers used mundane practices to unmake and remake the late-Victorian and Edwardian philanthropic legacy they inherited.
Long-term effects of previous oxandrolone treatment in adult women with Turner syndrome
Authors: Freriks Kim , Sas Theo C J , Traas Maaike A F , Netea-Maier Romana T , den Heijer Martin , Hermus Ad R M M , Wit Jan M , van Alfen-van der Velden Janiëlle A E M , Otten Barto J , de Muinck Keizer-Schrama Sabine M P F , Gotthardt Martin , Dejonckere Philippe H , Zandwijken Gladys R J , Menke Leonie A , Timmers Henri J L M
Published: October 2012

Objective

Short stature is a prominent feature of Turner syndrome (TS), which is partially overcome by GH treatment. We have previously reported the results of a trial on the effect of oxandrolone (Ox) in girls with TS. Ox in a dose of 0.03 mg/kg per day (Ox 0.03) significantly increased adult height gain, whereas Ox mg/kg per day (0.06) did not, at the cost of deceleration of breast development and mild virilization. The aim of this follow-up study in adult participants of the pediatric trial was to investigate the long-term effects of previous Ox treatment.

Design and methods

During the previous randomized controlled trial, 133 girls were treated with GH combined with placebo (Pl), Ox 0.03, or Ox 0.06 from 8 years of age and estrogen from 12 years. Sixty-eight women (Pl,n=23; Ox 0.03,n=27; and Ox 0.06,n=18) participated in the double-blind follow-up study (mean age, 24.0 years; mean time since stopping GH, 8.7 years; and mean time of Ox/Pl use, 4.9 years). We assessed height, body proportions, breast size, virilization, and body composition.

Results

Height gain (final minus predicted adult height) was maintained at follow-up (Ox 0.03 10.2±4.9 cm, Ox 0.06 9.7±4.4 cm vs Pl 8.0±4.6 cm). Breast size, Tanner breast stage, and body composition were not different between groups. Ox-treated women reported more subjective virilization and had a lower voice frequency.

Conclusion

Ox 0.03 mg/kg per day has a beneficial effect on adult height gain in TS patients. Despite previously reported deceleration of breast development during Ox 0.03 treatment, adult breast size is not affected. Mild virilization persists in only a small minority of patients. The long-term evaluation indicates that Ox 0.03 treatment is effective and safe.
Noncanonical suppression of GH-dependent isoforms of cytochrome P450 by the somatostatin analog octreotide
Authors: Das Rajat Kumar , Banerjee Sarmistha , Shapiro Bernard H
Published: October 2012

Octreotide is a potent somatostatin analog therapeutically used to treat several conditions including hyper GH secretion in patients with acromegaly. We infused, over 30 s, octreotide into male rats every 12 h for 6 days at levels considerably greater than typical human therapeutic doses. Unexpectedly, resulting circulating GH profile was characterized by pulses of higher amplitudes, longer durations, and greater total content than normal, but still contained an otherwise male-like episodic secretory profiles. In apparent disaccord, the normally elevated masculine expression levels (protein and/or mRNA) of CYP2C11 (accounting for >50% of the total hepatic cytochrome P450 content), CYP3A2, CYP2C7, and IGF1, dependent on the episodic GH profile, were considerably downregulated. We explain this contradiction by proposing that the requisite minimal GH-devoid interpulse durations in the masculine profile that solely regulate expression of at least CYP2C11 and IGF1 may be sufficiently reduced to suppress transcription of the hepatic genes. Alternatively, we observed that octreotide infusion may have acted directly on the hepatocytes to induce expression of immune response factors postulated to suppress CYP transcription and/or upregulate expression of several negative regulators (e.g. phosphatases and SOCS proteins) of the JAK2/STAT5B signaling pathway that normally mediates the upregulation of CYP2C11 and IGF1 by the masculine episodic GH profile.
Fatigue lives of self-compacting concrete and self-compacting fibre-reinforced concrete beams
Authors: Goel Sanjay , Singh Surinder Pal , Singh Partap
Published: October 2012

This paper presents results of an investigation conducted to estimate the mean and design fatigue lives of self-compacting concrete and self-compacting fibre-reinforced concrete beams containing 0·5% volume fraction of steel fibres. Approximately 19 flexural fatigue tests and 90 complementary static flexural strength tests were conducted on self-compacting concrete and self-compacting fibre-reinforced concrete beam specimens of 100 × 100 × 500 mm size. The distribution of fatigue life of self-compacting concrete and self-compacting fibre-reinforced concrete at different stress levels has been examined and Weibull distribution parameters have been obtained by different methods of analysis, which are subsequently used to estimate the mean and design fatigue lives of self-compacting concrete and self-compacting fibre-reinforced concrete. The performance of self-compacting concrete and self-compacting fibre-reinforced concrete have been found to be better, in terms of reduced variability in the distribution of fatigue lives and higher mean and design fatigue lives, compared to normally vibrated concrete and normally vibrated fibre reinforced concrete.
Effect of limestone addition on early-age properties of ultra high-performance concrete
Authors: Camiletti Jessica , Soliman Ahmed M. , Nehdi Moncef L.
Published: October 2012

In the present study, the effects of using limestone as partial replacement for cement on the early-age properties of ultra high-performance concrete cured at simulated cold and normal field conditions were investigated. Different particle sizes of limestone, ranging from nano (15–40 nm) up to 12 µm, were added at rates of 0, 5, 10 and 15% as partial volume replacement for cement. The results indicate that in very low water/cement ratio concrete mixtures, the incorporated micro-sized limestone acts mainly as an inert filler material, creating a denser microstructure and increasing the effective water/cement ratio. Although the mixtures incorporating micro-sized limestone exhibited mechanical properties that were comparable to or weaker than those of mixtures incorporating nano-sized calcium carbonate, they had similar or higher mechanical properties than those of the control mixture without limestone. Thus, environmentally friendly concrete can be produced using micro-limestone, by reducing the cement factor of ultra high-performance concrete while enhancing the mechanical properties
Slag material's proportion optimised by polynomial regression
Authors: Wang Jin , Sun Aizhi , Gao Qian , Zhai Fuqiang , Wu Shen , Volinsky Alex A.
Published: October 2012

Mixed activator agent for granulated blast furnace slag cementitious materials with potential hydraulic properties was prepared for tailings backfilling and optimised by the orthogonal test method and the Data Processing System analysis. The effects of lime, gypsum and cement clinker content on the 7 days compressive strength were investigated. Range and variance analysis, and quadratic polynomial step regression were used for analysing and optimising the formulation of the mixed activator agent. The optimised cementitious material contained 5% cement clinker, 15% lime and 4% gypsum. As a result, the maximum measured 7 days compressive strength was 2·79 MPa, which is 4·5 times higher than Portland cement (CEM I 32.5R). The difference between measured and predicted strength values was 4·5%, signifying good method applicability for slag cementing materials design.
Per capita invasion probabilities: an empirical model to predict rates of invasion via ballast water
Authors: Reusser Deborah A. , Lee II Henry , Frazier Melanie , Ruiz Gregory M. , Fofonoff Paul W. , Minton Mark S. , Miller A. Whitman
Published: October 2012

Ballast water discharges are a major source of species introductions into marine and estuarine ecosystems. To mitigate the introduction of new invaders into these ecosystems, many agencies are proposing standards that establish upper concentration limits for organisms in ballast discharge. Ideally, ballast discharge standards will be biologically defensible and adequately protective of the marine environment. We propose a new technique, the per capita invasion probability (PCIP), for managers to quantitatively evaluate the relative risk of different concentration‐based ballast water discharge standards. PCIP represents the likelihood that a single discharged organism will become established as a new nonindigenous species. This value is calculated by dividing the total number of ballast water invaders per year by the total number of organisms discharged from ballast. Analysis was done at the coast‐wide scale for the Atlantic, Gulf, and Pacific coasts, as well as the Great Lakes, to reduce uncertainty due to secondary invasions between estuaries on a single coast. The PCIP metric is then used to predict the rate of new ballast‐associated invasions given various regulatory scenarios. Depending upon the assumptions used in the risk analysis, this approach predicts that approximately one new species will invade every 10–100 years with the International Maritime Organization (IMO) discharge standard of <10 organisms with body size >50 μm per m3 of ballast. This approach resolves many of the limitations associated with other methods of establishing ecologically sound discharge standards, and it allows policy makers to use risk‐based methodologies to establish biologically defensible discharge standards.
In Vitro Analysis of the Efficacy of Ultrasonic Scalers and a Toothbrush for Removing Bacteria from Resorbable Blast Material Titanium Disks
Authors: Park Jun‐Beom , Jang Yun Ji , Koh Minchul , Choi Bong‐Kyu , Kim Kack‐Kyun , Ko Youngkyung
Published: October 2012

Background: A resorbable blast material (RBM) surface is reported to have a higher bone‐to‐implant contact percentage than machined surfaces, but modified surfaces with rougher textures have been shown to favor colonization by bacteria and development of peri‐implantitis. Therefore, this in vitro study compares the effects of different instruments on surface roughness and removal of bacteria from RBM titanium implant disks.

Methods: RBM titanium disks were treated with various ultrasonic scaler tips and a toothbrush, and change in surface roughness was measured by confocal microscopy. The disks were incubated with bacteria, and instruments made of carbon or plastic, two metal ultrasonic scaler tips, or a toothbrush were used to remove the attached bacteria. The amount of remaining bacteria was evaluated using a crystal violet assay.

Results: The change in surface structure following different treatment modalities was analyzed by confocal microscopy. A statistically significant decrease in the arithmetic mean value of RBM surfaces (Ra) was observed after treatment with an ultrasonic scaler with a metal tip. The use of a metal tip (rather than a carbon or plastic tip) and brushing with dentifrice was more efficient in removing bacteria from the contaminated titanium surface according to the crystal violet assay.

Conclusion: Within the limits of this study, the use of a metal tip may be effective in removing bacteria from contaminated surfaces.
Attitudes toward becoming a veterinarian in a group of undergraduate agriculture and biomedical sciences students
Authors: Daly Russell F. , Erickson Alan K.
Published: October 2012

Objective—To assess the level of interest of university students enrolled in veterinary science courses toward becoming a veterinarian, reasons supporting or discouraging their interest, when those attitudes were formed, and future plans for those pursuing veterinary medicine as a career.

Design—Cross-sectional study.

Sample—585 university students in South Dakota enrolled in 2 veterinary science courses over a 6-year period.

Procedures—Each year, students enrolled in the 2 courses answered survey questions pertaining to their interest in becoming a veterinarian, background, and future plans.

Results—Most students enrolled in these courses desired to become a veterinarian at some time in their lives. Females were more likely than males to indicate veterinary medicine as their current career choice. Most students developed their interest during grades 10 to 12. Females developed an interest in veterinary medicine earlier than did males. Enjoyment of animals, intellectual stimulation, and the opportunity to actively work outdoors were cited frequently as reasons for interest in veterinary medicine. Increased duration of education, high educational costs, and preveterinary coursework difficulty were major reasons for disinterest in becoming a veterinar-ian. Of students pursuing the profession, desired practice type correlated strongly with previous animal experience.

Conclusions and Clinical Relevance—Considering that most students, especially males, developed their interest in veterinary medicine during grades 10 to 12, elementary school may be the best starting point for exposing students to veterinary medicine. To increase interest in large animal practice among students entering veterinary school, livestock experiences should be provided to children with no farm experience during their elementary, middle, and high school years. In our survey population, cost and duration of veterinary education had a significant negative influence on student interest in the profession.
Effectiveness and adverse effects of the use of apomorphine and 3% hydrogen peroxide solution to induce emesis in dogs
Authors: Khan Safdar A. , Mclean Mary Kay , Slater Margaret , Hansen Steven , Zawistowski Stephen
Published: October 2012

Objective—To determine the effectiveness and adverse effects of apomorphine and 3% hydrogen peroxide solution used for emesis in dogs.

Design—Prospective observational study.

Animals—147 dogs that received apomorphine (IV or placed in the conjunctival sac) or 3% hydrogen peroxide solution (PO) to induce emesis after exposure to toxic agents.

Procedures—Data regarding signalment; agent information; type, dose, route, and number of emetic administrations; whether emesis was successful; number of times emesis occurred; percentage of ingested agent recovered; and adverse effects were collected via telephone during American Society for the Prevention of Cruelty to Animals Animal Poison Control Center operations and stored in a database for analysis. Mann-Whitney and Fisher exact tests were used to evaluate emetic success rates.

Results—Apomorphine and 3% hydrogen peroxide solution successfully induced emesis in 59 of 63 (94%) and 76 of 84 (90%) of dogs, respectively. Mean time to onset of emesis after the first dose of emetic was 14.5 and 18.6 minutes when hydrogen peroxide (n = 37) and apomorphine (31) were used, respectively, with mean durations of 42 and 27 minutes, respectively. Mean estimates for recovery of ingested agents were 48% for hydrogen peroxide and 52% for apomorphine. Adverse effects were reported in 16 of 112 (14%) dogs for which information was available.

Conclusions and Clinical Relevance—3% hydrogen peroxide solution and apomorphine effectively induced emesis in dogs when used as directed. Emesis occurred within minutes after administration and helped recover substantial amounts of ingested agents. Adverse effects of both emetics were considered mild and self-limiting.