bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Investigation of Preheated Jatropha Oil Fuelled Direct Injection Compression Ignition Engine—Part 2: Engine Durability and Effect on Lubricating Oil
Authors: Agarwal Avinash Kumar , Dhar Atul
Published: January 2010

Straight vegetable oil utilization as diesel engine fuel has the advantage of eliminating the energy, time, and cost involved in biodiesel production. Since straight vegetable oils have relatively higher viscosity compared to mineral diesel, they have to be modified to bring their combustion related properties closer to mineral diesel. In this study, a heat exchanger was used to utilize the waste heat of engine exhaust gas for reducing the viscosity of jatropha oil, and the performance, emission, and combustion characteristics are described in the first part of the paper. Carbon deposits, wear of vital engine parts, and the effect of jatropha oil on lubricating oil properties were analyzed in long-term endurance test for 512 h. The effect on lubricating oil of heated jatropha oil (J100) as well as 50 % blend of jatropha oil (J50) were compared with mineral diesel by comparing the lubricant’s density, viscosity, flash point, carbon residue, ash content, copper corrosion, and pentane and benzene insoluble measurements after an interval of every 128 h. Wear of the cylinder liner, diameter of piston, piston rings, gudgeon pin, and small and big-end bearings for J100 and J50 were measured vis-à-vis mineral diesel. Jatropha oil fuelled engine first undergoes lowering of lubricating oil viscosity followed by severe vegetable oil initiated oxidation of lubricating oil base-stock and thus the life of the lubricating oil gets depleted in approximately 400 h. The wear of J50 fuelled engine liner is found to be relatively lower compared to mineral diesel fuelled engine.
Glass Formation and Mechanical Properties of Ti–Cu–Ni Alloys with High Ti Content
Authors: Zhang S. G. , Hu G. H. , Meng Q. G. , Li J. G.
Published: January 2010

A series of Ti–Cu–Ni alloys with Ti content as high as 50–70 at. % expected to possess potential high glass-forming ability (GFA) was designed according to the ε criterion (Xia, M. X., Zhang, S. G., Ma, C. L., and Li, J. G., “Evaluation of Glass-Forming Ability for Metallic Glasses Based on Order-Disorder Competition,” Appl. Phys. Lett. Vol. 89, 2006, pp. 091917-1–091917-3) and were prepared by melt spinning and suck casting methods. The samples were examined by X-ray diffractometry, differential scanning calorimetry, optical microscopy, scanning electronic microscopy, and quasistatic compression test. The GFA of the melt-spun ribbons is enhanced with increasing ε. Ti58Cu32Ni10 alloy with the maximum designed ε value of 0.542 exhibits best GFA with a glass transition temperature of 627 K and a wide supercooled liquid region of 45 K. However, this alloy failed to form a fully glassy rod of 1 mm in diameter. Room temperature compression tests reveal that the 1 mm diameter Ti58Cu32Ni10 glass composite exhibits work-hardening characteristic, with ultimate compressive stress of 2418 MPa, yielding stress σ0.2 of 1448 MPa and about 7.8 % plastic strain. The combination of high strength and ductility was attributed to a dendritic TiCu(Ni) network embedded in the hard glass matrix.
Initiation Behavior of Crack Originated from Non-Metallic Inclusion in Rolling Contact Fatigue
Authors: Tsunekage Norimasa , Hashimoto Kazuya , Fujimatsu Takeshi , Hiraoka Kazuhiko
Published: January 2010

Recently, it has been generally accepted that flaking life is dependent on the size of non-metallic inclusion under proper condition in bearing use. Statistics of extreme values to predict the maximum non-metallic inclusion size and ultrasonic test to assess large non-metallic inclusions in a large volume are widely used as practical methods for the evaluation of bearing steel cleanliness. Murakami’s formula is well known, which describes the relationship between non-metallic inclusion size and fatigue strength. However, the formula cannot be directly applied to rolling contact fatigue because of the difference in applied stress mode. While the equation was invented to predict the fatigue limit in principal stress mode, rolling contact fatigue is mainly caused by shear stress. It is expected that the condition of bearing use will be more critical due to the downsizing tendency in various industrial or automotive machine units. Thus the research on the flaking mechanism becomes more important from the viewpoint of global ecology because that is beneficial to the improvement in bearing life and methods for cleanliness evaluation. Due to the difficulty in experimental observation, however, the details of the flaking mechanism in rolling contact fatigue caused by non-metallic inclusion has not yet been clarified. Focusing on the relationship between non-metallic inclusion and initiation of the crack, the flaking mechanism is proposed in this paper.
Licking-Induced Synchrony in the Taste–Reward Circuit Improves Cue Discrimination during Learning
Authors: Gutierrez Ranier , Simon Sidney A. , Nicolelis Miguel A. L.
Published: January 2010

Animals learn which foods to ingest and which to avoid. Despite many studies, the electrophysiological correlates underlying this behavior at the gustatory–reward circuit level remain poorly understood. For this reason, we measured the simultaneous electrical activity of neuronal ensembles in the orbitofrontal cortex, insular cortex, amygdala, and nucleus accumbens while rats licked for taste cues and learned to perform a taste discrimination go/no-go task. This study revealed that rhythmic licking entrains the activity in all these brain regions, suggesting that the animal's licking acts as an “internal clock signal” against which single spikes can be synchronized. That is, as animals learned a go/no-go task, there were increases in the number of licking coherent neurons as well as synchronous spiking between neuron pairs from different brain regions. Moreover, a subpopulation of gustatory cue-selective neurons that fired in synchrony with licking exhibited a greater ability to discriminate among tastants than nonsynchronized neurons. This effect was seen in all four recorded areas and increased markedly after learning, particularly after the cue was delivered and before the animals made a movement to obtain an appetitive or aversive tastant. Overall, these results show that, throughout a large segment of the taste–reward circuit, appetitive and aversive associative learning improves spike-timing precision, suggesting that proficiency in solving a taste discrimination go/no-go task requires licking-induced neural ensemble synchronous activity.
Glycine Release from Radial Cells Modulates the Spontaneous Activity and Its Propagation during Early Spinal Cord Development
Authors: Scain Anne-Laure , Le Corronc Hervé , Allain Anne-Emilie , Muller Emilie , Rigo Jean-Michel , Meyrand Pierre , Branchereau Pascal , Legendre Pascal
Published: January 2010

Rhythmic electrical activity is a hallmark of the developing embryonic CNS and is required for proper development in addition to genetic programs. Neurotransmitter release contributes to the genesis of this activity. In the mouse spinal cord, this rhythmic activity occurs after embryonic day 11.5 (E11.5) as waves spreading along the entire cord. At E12.5, blocking glycine receptors alters the propagation of the rhythmic activity, but the cellular source of the glycine receptor agonist, the release mechanisms, and its function remain obscure. At this early stage, the presence of synaptic activity even remains unexplored. Using isolated embryonic spinal cord preparations and whole-cell patch-clamp recordings of identified motoneurons, we find that the first synaptic activity develops at E12.5 and is mainly GABAergic. Using a multiple approach including direct measurement of neurotransmitter release (i.e., outside-out sniffer technique), we also show that, between E12.5 and E14.5, the main source of glycine in the embryonic spinal cord is radial cell progenitors, also known to be involved in neuronal migration. We then demonstrate that radial cells can release glycine during synaptogenesis. This spontaneous non-neuronal glycine release can also be evoked by mechanical stimuli and occurs through volume-sensitive chloride channels. Finally, we find that basal glycine release upregulates the propagating spontaneous rhythmic activity by depolarizing immature neurons and by increasing membrane potential fluctuations. Our data raise the question of a new role of radial cells as secretory cells involved in the modulation of the spontaneous electrical activity of embryonic neuronal networks.
Delayed Intrinsic Activation of an NMDA-Independent CaM-kinase II in a Critical Time Window Is Necessary for Late Consolidation of an Associative Memory
Authors: Wan Huimin , Mackay Beth , Iqbal Hassan , Naskar Souvik , Kemenes György
Published: January 2010

Calcium/calmodulin-dependent kinases (CaM-kinases) are central to various forms of long-term memory (LTM) in a number of evolutionarily diverse organisms. However, it is still largely unknown what contributions specific CaM-kinases make to different phases of the same specific type of memory, such as acquisition, or early, intermediate, and late consolidation of associative LTM after classical conditioning. Here, we investigated the involvement of CaM-kinase II (CaMKII) in different phases of associative LTM induced by single-trial reward classical conditioning inLymnaea, a well established invertebrate experimental system for studying molecular mechanisms of learning and memory. First, by using a general CaM-kinase inhibitor, KN-62, we found that CaM-kinase activation was necessary for acquisition and late consolidation, but not early or intermediate consolidation or retrieval of LTM. Then, we used Western blot-based phosphorylation assays and treatment with CaMKIINtide to identify CaMKII as the main CaM-kinase, the intrinsic activation of which, in a critical time window (∼24 h after learning), is central to late consolidation of LTM. Additionally, using MK-801 and CaMKIINtide we found that acquisition was dependent on both NMDA receptor and CaMKII activation. However, unlike acquisition, CaMKII-dependent late memory consolidation does not require the activation of NMDA receptors. Our new findings support the notion that even apparently stable memory traces may undergo further molecular changes and identify NMDA-independent intrinsic activation of CaMKII as a mechanism underlying this “lingering consolidation.” This process may facilitate the preservation of LTM in the face of protein turnover or active molecular processes that underlie forgetting.
Progressive and Lasting Amplification of Accumbal Nicotine-Seeking Neural Signals
Authors: Guillem Karine , Peoples Laura L.
Published: January 2010

Although neuroadaptations in the nucleus accumbens (NAc) are thought to contribute to nicotine addiction, little is known about the chronic effects of nicotine on NAc neuronal activity. In the present experiment, rats were exposed to a 23 d period of nicotine self-administration (SA), a 30 d abstinence period, and a 7 d period of reexposure to SA. Chronic electrophysiological procedures were used to record the activity of individual NAc neurons on the 3rd and 23rd days of initial SA and on the 1st, 3rd, and 7th days of reexposure. Between-session comparisons showed that NAc neurons exhibit two patterns of plasticity under the present experimental conditions. First, phasic-increase firing patterns time-locked to the nicotine-reinforced lever press do not change during initial SA, but then show increases in prevalence and amplitude after abstinence, which persist during reexposure. Second, for neurons that show no phasic response time-locked to the nicotine-reinforced lever press, average baseline and SA firing rates decrease during initial SA, return to normal during abstinence, and decrease again during reexposure. As a combined consequence of the two types of neurophysiological plasticity, average firing rate of NAc neurons at the time of nicotine-directed behavior undergoes a progressive and persistent net amplification, across the successive stages of SA, abstinence, and reexposure. This net increase in NAc firing at the time of nicotine-directed behavior occurs in association with an increase in animals' motivation to seek nicotine. The adaptations that occur in nicotine-exposed animals do not occur in animals exposed to sucrose. The NAc neurophysiological plasticity potentially contributes to compulsive tobacco use.
Glutamatergic and Nonglutamatergic Neurons of the Ventral Tegmental Area Establish Local Synaptic Contacts with Dopaminergic and Nondopaminergic Neurons
Authors: Dobi Alice , Margolis Elyssa B. , Wang Hui-Ling , Harvey Brandon K. , Morales Marisela
Published: January 2010

The ventral tegmental area (VTA) contributes to reward and motivation signaling. In addition to the well established populations of dopamine (DA) or GABA VTA neurons, glutamatergic neurons were recently discovered in the VTA. These glutamatergic neurons express the vesicular glutamate transporter 2, VGluT2. To investigate whether VTA glutamatergic neurons establish local synapses, we tagged axon terminals from resident VTA neurons by intra-VTA injection ofPhaseolus vulgarisleucoagglutinin (PHA-L) or an adeno-associated virus encoding wheat germ agglutinin (WGA) and by immunoelectron microscopy determined the presence of VGluT2 in PHA-L- or WGA-positive terminals. We found that PHA-L- or WGA-positive terminals from tagged VTA cells made asymmetric or symmetric synapses within the VTA. VGluT2 immunoreactivity was detected in the vast majority of PHA-L- or WGA-positive terminals forming asymmetric synapses. These results indicate that both VTA glutamatergic and nonglutamatergic (likely GABAergic) neurons establish local synapses. To examine the possible DAergic nature of postsynaptic targets of VTA glutamatergic neurons, we did triple immunolabeling with antibodies against VGluT2, tyrosine hydroxylase (TH), and PHA-L. From triple-labeled tissue, we found that double-labeled PHA-L (+)/VGluT2 (+) axon terminals formed synaptic contacts on dendrites of both TH-positive and TH-negative cells. Consistent with these anatomical observations, in whole-cell slice recordings of VTA neurons we observed that blocking action potential activity significantly decreased the frequency of synaptic glutamatergic events in DAergic and non-DAergic neurons. These observations indicate that resident VTA glutamatergic neurons are likely to affect both DAergic and non-DAergic neurotransmission arising from the VTA.
Death-Associated Protein Kinase-Mediated Cell Death Modulated by Interaction with DANGER
Authors: Kang Bingnan N. , Ahmad Abdullah S. , Saleem Sofiyan , Patterson Randen L. , Hester Lynda , Doré Sylvain , Snyder Solomon H.
Published: January 2010

Death-associated protein kinase (DAPK) is a key player in multiple cell death signaling pathways. We report that DAPK is regulated by DANGER, a partial MAB-21 domain-containing protein. DANGER binds directly to DAPK and inhibits DAPK catalytic activity. DANGER-deficient mouse embryonic fibroblasts and neurons exhibit greater DAPK activity and increased sensitivity to cell death stimuli than do wild-type control cells. In addition, DANGER-deficient mice manifest more severe brain damage after acute excitotoxicity and transient cerebral ischemia than do control mice. Accordingly, DANGER may physiologically regulate the viability of neurons and represent a potential therapeutic target for stroke and neurodegenerative diseases.
Quantitative Comparison of Glutamatergic and GABAergic Synaptic Vesicles Unveils Selectivity for Few Proteins Including MAL2, a Novel Synaptic Vesicle Protein
Authors: Grønborg Mads , Pavlos Nathan J. , Brunk Irene , Chua John J. E. , Münster-Wandowski Agnieszka , Riedel Dietmar , Ahnert-Hilger Gudrun , Urlaub Henning , Jahn Reinhard
Published: January 2010

Synaptic vesicles (SVs) store neurotransmitters and release them by exocytosis. The vesicular neurotransmitter transporters discriminate which transmitter will be sequestered and stored by the vesicles. However, it is unclear whether the neurotransmitter phenotype of SVs is solely defined by the transporters or whether it is associated with additional proteins. Here we have compared the protein composition of SVs enriched in vesicular glutamate (VGLUT-1) and GABA transporters (VGAT), respectively, using quantitative proteomics. Of >450 quantified proteins, ∼50 were differentially distributed between the populations, with only few of them being specific for SVs. Of these, the most striking differences were observed for the zinc transporter ZnT3 and the vesicle proteins SV2B and SV31 that are associated preferentially with VGLUT-1 vesicles, and for SV2C that is associated mainly with VGAT vesicles. Several additional proteins displayed a preference for VGLUT-1 vesicles including, surprisingly, synaptophysin, synaptotagmins, and syntaxin 1a. Moreover, MAL2, a membrane protein of unknown function distantly related to synaptophysins and SCAMPs, cofractionated with VGLUT-1 vesicles. Both subcellular fractionation and immunolocalization at the light and electron microscopic level revealed that MAL2 is a bona-fide membrane constituent of SVs that is preferentially associated with VGLUT-1-containing nerve terminals. We conclude that SVs specific for different neurotransmitters share the majority of their protein constituents, with only few vesicle proteins showing preferences that, however, are nonexclusive, thus confirming that the vesicular transporters are the only components essential for defining the neurotransmitter phenotype of a SV.
Recruitment of Early Postnatal Parvalbumin-Positive Hippocampal Interneurons by GABAergic Excitation
Authors: Sauer Jonas-Frederic , Bartos Marlene
Published: January 2010

GABAergic synaptic inputs targeting cortical principal cells undergo marked changes in their functional properties from depolarizing at early postnatal life to hyperpolarizing at mature stages. In contrast, the nature of GABAAreceptor-mediated signaling in interneurons during maturation of neuronal networks is controversial. By using gramicidin perforated-patch and whole-cell recordings from LIM homeobox 6 (Lhx6)-positive dentate gyrus perisomatic-targeting parvalbumin-expressing interneurons (PV-INs), we show that signaling at first formed GABAergic synapses at postnatal day 3 (P3) is excitatory and switches to shunting during the course of the first to second postnatal week. GABAergic synaptic inputs at P3–P6 reliably evoke action potentials in 65% of Lhx6-EGFP-expressing perisomatic-targeting cells and boost spike induction upon conjoint activation of glutamatergic fibers. Thus, GABAergic inputs change their functional role during maturation. They facilitate the recruitment of perisomatic-targeting INs in early postnatal circuits when network connectivity and synaptic glutamate receptor-mediated excitation are low and control spike timing at later stages when connectivity and glutamate-mediated drive are high.
Reduction of Adult Hippocampal Neurogenesis Confers Vulnerability in an Animal Model of Cocaine Addiction
Authors: Noonan Michele A. , Bulin Sarah E. , Fuller Dwain C. , Eisch Amelia J.
Published: January 2010

Drugs of abuse dynamically regulate adult neurogenesis, which appears important for some types of learning and memory. Interestingly, a major site of adult neurogenesis, the hippocampus, is important in the formation of drug–context associations and in the mediation of drug-taking and drug-seeking behaviors in animal models of addiction. Correlative evidence suggests an inverse relationship between hippocampal neurogenesis and drug-taking or drug-seeking behaviors, but the lack of a causative link has made the relationship between adult-generated neurons and addiction unclear. We used rat intravenous cocaine self-administration in rodents, a clinically relevant animal model of addiction, to test the hypothesis that suppression of adult hippocampal neurogenesis enhances vulnerability to addiction and relapse. Suppression of adult hippocampal neurogenesis via cranial irradiation before drug-taking significantly increased cocaine self-administration on both fixed-ratio and progressive-ratio schedules, as well as induced a vertical shift in the dose–response curve. This was not a general enhancement of learning, motivation, or locomotion, because sucrose self-administration and locomotor activity were unchanged in irradiated rats. Suppression of adult hippocampal neurogenesis after drug-taking significantly enhanced resistance to extinction of drug-seeking behavior. These studies identify reduced adult hippocampal neurogenesis as a novel risk factor for addiction-related behaviors in an animal model of cocaine addiction. Furthermore, they suggest that therapeutics to specifically increase or stabilize adult hippocampal neurogenesis could aid in preventing initial addiction as well as future relapse.
Ca2+/Calmodulin-Dependent Protein Kinase IIα Is Required for the Initiation and Maintenance of Opioid-Induced Hyperalgesia
Authors: Chen Yan , Yang Cheng , Wang Zaijie Jim
Published: January 2010

Repeated administration of opioids not only leads to tolerance and dependence, but also results in nociceptive enhancement called opioid-induced hyperalgesia (OIH). Nociceptive mediators involved in OIH generation remain poorly understood. In the present study, we tested the hypothesis that Ca2+/calmodulin-depent protein kinase II (CaMKIIα) is critical for OIH. Opioid-induced hyperalgesia was produced by repeated morphine administration or pellet implantation in mice. Correlating with the development of tactile allodynia and thermal hyperalgesia, spinal CaMKIIα activity was significantly increased in OIH. KN93, a CaMKII inhibitor, dose- and time-dependently reversed OIH and CaMKII activation without impairing locomotor coordination. To elucidate the specific CaMKII isoform involved, we targeted CaMKIIα by using small interfering RNA and demonstrated that knockdown of spinal CaMKIIα attenuated OIH. Furthermore, morphine failed to induce OIH in CaMKIIαT286Apoint mutant mice, although wild-type littermate mice developed robust OIH after repeated treatments with morphine. These data implicate, for the first time, an essential role of CaMKIIα as a cellular mechanism leading to and maintaining opioid-induced hyperalgesia.
Trans-Splicing-Mediated Improvement in a Severe Mouse Model of Spinal Muscular Atrophy
Authors: Coady Tristan H. , Lorson Christian L.
Published: January 2010

Spinal muscular atrophy is a leading genetic cause of infantile death and occurs in ∼1/6000 live births. SMA is caused by the loss ofSurvival Motor Neuron-1(SMN1), however, all patients retain at least one copy of a nearly identical gene calledSMN2. WhileSMN2andSMN1are comprised of identical coding sequences, the majority ofSMN2transcripts are alternatively spliced, encoding a truncated protein that is unstable and nonfunctional. Considerable effort has focused upon modulating theSMN2alternative splicing event since this would produce more wild-type protein. Recently we reported the development of an optimizedtrans-splicing system that involved the coexpression of aSMN2 trans-splicing RNA and an antisense RNA that blocks a downstream splice site inSMN2pre-mRNA. Here, we demonstrate thatin vivodelivery of the optimizedtrans-splicing vector increases an important SMN-dependent activity, snRNP assembly, in disease-relevant tissue in the SMA mouse model. A single injection of the vector into the intracerebral-ventricular space in SMA neonates also lessens the severity of the SMA phenotype in a severe SMA mouse model, extending survival ∼70%. Collectively, these results provide the firstin vivodemonstration thatSMN2 trans-splicing leads to a lessening of the severity of the SMA phenotype and provide evidence for the power of this strategy for reprogramming genetic diseases at the pre-mRNA level.
SNAP-25 Is a Target of Protein Kinase C Phosphorylation Critical to NMDA Receptor Trafficking
Authors: Lau C. Geoffrey , Takayasu Yukihiro , Rodenas-Ruano Alma , Paternain Ana V. , Lerma Juan , Bennett Michael V. L. , Zukin R. Suzanne
Published: January 2010

Protein kinase C (PKC) enhances NMDA receptor (NMDAR)-mediated currents and promotes NMDAR delivery to the cell surface via SNARE-dependent exocytosis. Although the mechanisms of PKC potentiation are established, the molecular target of PKC is unclear. Here we show that synaptosomal-associated protein of 25 kDa (SNAP-25), a SNARE protein, is functionally relevant to PKC-dependent NMDAR insertion, and identify serine residue-187 as the molecular target of PKC phosphorylation. Constitutively active PKC delivered via the patch pipette potentiated NMDA (but not AMPA) whole-cell currents in hippocampal neurons. Expression of RNAi targeting SNAP-25 or mutant SNAP-25(S187A) and/or acute disruption of the SNARE complex by treatment with BoNT A, BoNT B or SNAP-25 C-terminal blocking peptide abolished NMDAR potentiation. A SNAP-25 peptide and function-blocking antibody suppressed PKC potentiation of NMDA EPSCs at mossy fiber-CA3 synapses. These findings identify SNAP-25 as the target of PKC phosphorylation critical to PKC-dependent incorporation of synaptic NMDARs and document a postsynaptic action of this major SNARE protein relevant to synaptic plasticity.
Many Neuronal and Behavioral Impairments in Transgenic Mouse Models of Alzheimer's Disease Are Independent of Caspase Cleavage of the Amyloid Precursor Protein
Authors: Harris Julie A. , Devidze Nino , Halabisky Brian , Lo Iris , Thwin Myo T. , Yu Gui-Qiu , Bredesen Dale E. , Masliah Eliezer , Mucke Lennart
Published: January 2010

Previous studies suggested that cleavage of the amyloid precursor protein (APP) at aspartate residue 664 by caspases may play a key role in the pathogenesis of Alzheimer's disease. Mutation of this site (D664A) prevents caspase cleavage and the generation of the C-terminal APP fragments C31 and Jcasp, which have been proposed to mediate amyloid-β (Aβ) neurotoxicity. Here we compared human APP transgenic mice with (B254) and without (J20) the D664A mutation in a battery of tests. Before Aβ deposition, hAPP–B254 and hAPP–J20 mice had comparable hippocampal levels of Aβ1-42. At 2–3 or 5–7 months of age, hAPP–B254 and hAPP–J20 mice had similar abnormalities relative to nontransgenic mice in spatial and nonspatial learning and memory, elevated plus maze performance, electrophysiological measures of synaptic transmission and plasticity, and levels of synaptic activity-related proteins. Thus, caspase cleavage of APP at position D664 and generation of C31 do not play a critical role in the development of these abnormalities.
Identificação de enfermidades agudas causadas por animais e plantas em ambientes rurais e litorâneos: auxílio à prática dermatológica
Authors: Haddad Junior Vidal
Published: January 2010

FUNDAMENTOS: Nos últimos anos, existe um aumento progressivo do contato de moradores urbanos com ambientes selvagens devido a atividades de lazer. Com isso, algumas dermatites pouco conhecidas podem ser observadas nas clínicas privadas e ambulatórios dermatológicos, especialmente nos inícios de semana e finais de férias. OBJETIVOS: Obter e fornecer informações para dermatologistas sobre o problema. PACIENTES E MÉTODOS: O autor observou, em adultos e crianças, dermatites agudas associadas a plantas ou animais em Ubatuba, cidade litorânea de São Paulo, por dois meses (junho/julho de 2006) e na Faculdade de Medicina de Botucatu, também por dois meses (junho/julho de 2007). RESULTADOS: Foram observados 25 pacientes na área rural e 43 na área litorânea nas condições estabelecidas. Em áreas rurais, foram mais observadas fitofotodermatites e picadas de insetos, enquanto em áreas litorâneas traumas por ouriços-do-mar e fitofotodermatites predominaram; entretanto, em ambas as áreas ocorreram outros acidentes de difícil identificação na prática diária. CONCLUSÕES: Devemos estar atentos ao fato de o paciente procurar o dermatologista somente após as fases agudas dos acidentes. Informações sobre as enfermidades mais comuns e suas características podem ser muito úteis para a prática nos consultórios. O autor sugere uma tabela algorítmica para auxílio diagnóstico.
Polimorfismo Val247Leu do gene β2-glicoproteína 1 pode justificar a gênese de anticorpos antiβ2GP1 e síndrome do anticorpo antifosfolípide na hanseníase multibacilar
Authors: Brochado Maria José Franco , Nascimento Margarida Maria Passeri do , Louzada Junior Paulo , Figueiredo José Fernando C. , Roselino Ana Maria
Published: January 2010

FUNDAMENTOS - Anticorpos antifosfolípides (AAF), como antiβ2GP1 (β2-glicoproteína 1), são descritos na hanseníase multibacilar (MB) sem, contudo, caracterizar a síndrome do anticorpo antifosfolípide (SAF), constituída por fenômenos tromboembólicos (FTE). A mutação Val247Leu no V domínio da β2GP1 - substituição da leucina por valina - expõe epítopos crípticos com consequente formação de anticorpos antiβ2GP1. OBJETIVO: Avaliar a associação do polimorfismo Val247Leu do gene β2GP1 com títulos de anticorpos antiβ2GP1 na hanseníase. MÉTODO: O polimorfismo Val247Leu foi detectado por PCR-RFLP, e os títulos de anticorpos antiβ2GP1, por Elisa. RESULTADOS: O genótipo Val/Val estatisticamente predominou no grupo de hansênicos, em relação ao controle. Embora maiores títulos de anticorpos antiβ2GP1 IgM estivessem alocados no grupo MB com genótipos Val/Val e Val/Leu, não houve diferença estatística em relação ao genótipo Leu/Leu. Dos sete pacientes MB com FTE, quatro apresentaram heterozigose, e três Val/Val homozigose. CONCLUSÃO: A prevalência do genótipo Val/Val no grupo de hansênicos pode justificar parcialmente a presença de anticorpos antiβ2GP1 na forma MB. A heterozigose ou homozigose Val/Val nos sete pacientes com hanseníase MB e FTE corroboram a implicação de expressão fenotípica anômala da β2GPl e formação de anticorpos antiβ2GPl, com consequente FTE e SAF.
Prevalência de hiperidrose em uma amostra populacional de Blumenau - SC, Brasil
Authors: Felini Romero , Demarchi Alexandre Roberto , Fistarol Eder Deivis , Matiello Mariana , Delorenze Lílian Mathias
Published: January 2010

FUNDAMENTOS: A hiperidrose é um distúrbio pouco conhecido, caracterizado pela produção excessiva de suor. Manifesta-se sob várias formas, afetando áreas como axilas, mãos, pés e face. Seus sintomas trazem prejuízos para o paciente, desde limitações no trabalho até constrangimento social e transtornos psicológicos. OBJETIVOS: O objetivo deste trabalho é estimar a prevalência de hiperidrose na cidade de Blumenau. MÉTODOS: A pesquisa foi realizada entre 21 de agosto e 1o de setembro de 2006, nos terminais urbanos de Blumenau: SC, entrevistando-se 500 pessoas abordadas de forma aleatória. RESULTADOS: Dentre os entrevistados, 45 deles, que correspondem a 9% do total, preencheram os requisitos mínimos para serem classificados como portadores de hiperidrose. A faixa etária mais acometida foi entre 18 e 30 anos (11,8%). O número de portadores de hiperidrose do sexo masculino foi maior em números tanto absolutos quanto relativos. A característica mais prevalente foi frequência de hiperidrose ao menos uma vez por semana, encontrada em 91,11% dos afetados; a menos prevalente foi cessação de suor durante o sono, presente em 37,77%. CONCLUSÕES: Observa-se que a prevalência de hiperidrose em Blumenau é maior que a encontrada em outras pesquisas semelhantes, não evidenciando raridade na presente amostra.
Doença de Fabry
Authors: Boggio Paula , Luna Paula Carolina , Abad María Eugenia , Larralde Margarita
Published: January 2010

A doença de Fabry é enfermidade de armazenamento lisossômico rara, ligada ao cromossomo-X, causada pela deficiência parcial ou completa da enzima alfagalactosidase A. O defeito resulta no acúmulo de globotriaosilceramida no endotélio vascular e tecidos viscerais, sendo a pele, o coração, os rins e o sistema nervoso central os mais afetados. As autoras realizam revisão da literatura relacionada a essa afecção e ressaltam que o reconhecimento precoce dos angioqueratomas e da hipoidrose constitui sinal-chave no diagnóstico dessa doença grave. Destacam também a necessidade de esses doentes serem avaliados por equipe multidisciplinar.
Histiocitose de células de Langerhans: doença de Letterer-Siwe - importância do diagnóstico dermatológico em dois casos
Authors: Ferreira Leonardo Mello , Emerich Paulo Sergio , Diniz Lucia Martins , Lage Luciene , Redighieri Isabella
Published: January 2010

A histiocitose de células de Langerhans é proliferação clonal de células fenotipicamente semelhantes às células de Langerhans. Anteriormente denominada Letterer-Siwe, é a forma mais comum e mais grave dessa enfermidade, acometendo sobretudo crianças até os dois anos de idade. São apresentados dois casos dessa rara doença, diagnosticados após parecer dermatológico, destacando-se seus aspectos mais característicos.
Two New Species of Choreutinula (Collembola: Hypogastruridae) from America and China
Authors: Palacios-Vargas José G , Castaño-Meneses Gabriela , Gao Yang
Published: January 2010

Two new species of Choreutinula Paclt 1944 are described and illustrated. One American, from North Dakota, which differs from other species by the presence of 4+4 setae on ventral tube and small setae p3 on Abd. V. The other species is from China, resembles Choreutinula inermis (Tullberg, 1871), is the second species of the genus recorded from Asia, and it differs from other species by the presence of 4+4 setae on ventral tube, as the American species, but shows nine tubercles between setae p1-p1 on Abd. IV and has the unguiculus as a minute bristle. A key for the six species now known in the genus is given.
Life History Studies of Homalodisca vitripennis (Hemiptera: Cicadellidae), a Vector of Pierce's Disease of Grapevine
Authors: Lauzière Isabelle , Sétamou Mamoudou
Published: January 2010

Homafodisca vitripennis (Germar) (Hemiptera: Cicadellidae) vectors Xylella fastidiosa, a bacterium causing Pierce's disease in grapevine. The development and reproductive biology of this economically important insect species were studied under greenhouse and laboratory conditions during the spring—summer and fall—winter and at different rearing densities. The greenhouse was heated during the cool months to match summer temperatures and photoperiods were enhanced artificially. Longevity was affected by sex and season, with winter individuals living significantly longer than summer males (6.5-fold) and females (two-fold). Vitellogenesis was delayed in fall female H. vitripennis and a higher variability in lifetime fecundities was also observed. Longevity and the factors influencing it such as environmental conditions and availability of food sources are key factors determining fecundity in H. vitripennis. Offspring performance (developmental time, survival) was moderate during the cool months, although development of nymphs to adulthood was ≈13% greater. Rearing densities affected developmental time, survival, and egg production. Egg production per capita was higher in winter adults and the largest egg output was obtained at a rearing density of 100 nymphs per cage. Data presented herein suggest that nymph and adult H. vitripennis have evolved to ensure that only resistant stages are exposed to seasonal hazards. Captive adult females entered reproductive diapause in the fall as wild females would and despite warm greenhouse temperatures and long photoperiods and nymphal development decreased three- to six-fold during the fall-winter depending on rearing densities. These traits may be critical for the species to perpetuate in its native range.
Effect of Diet on Development and Reproduction of Pezothrips kellyanus (Thysanoptera: Thripidae)
Authors: Varikou K N , Tsitsipis I , Alexandrakis V
Published: January 2010

The developmental time, fecundity, and longevity of Pezothrips kellyanus (Bagnall) (Thysanoptera: Thripidae) encaged on lemon, Citrus limon (L.) Burm.f., leaves supplied with different food sources (pollen, sucrose, and honey) were compared at 25°C. Only the addition of pollen offered a nutritional benefit for this thrips species. Pollen to the lemon leaf reduced total developmental time from egg to adult from 12.42 to 9.68 d, increased survival from 22.6 to 80.6%, and increased fecundity. When sugar was offered, only 10% of larvae survived. P. kellyanus larvae were unable to grow on lemon leaves as well as when honey was supplied to the leaves (recorded survival was 22.6 and 42.86%, respectively), and adult females were slightly able to reproduce (1.4 and 4.2 larvae per female, respectively). Pollen and honey supplements fed to adults double and triple adult longevity, respectively.
Inheritance and Linkage Studies on Eye Color Mutations in Anastrepha ludens (Diptera: Tephritidae)
Authors: Zepeda-Cisneros C S , Meza J S , Gálvez S , Ibañez J , Robinson A S
Published: January 2010

Results of a study of the inheritance and linkage relationships of eye-color mutations in the Mexican fruit fly, Anastrepha ludens (Loew) (Diptera: Tephritidae), are presented. The mutations white eyes (we) and yellow eyes (ye) are recessive and autosomal, whereas Red eyes (Re) and Violet eyes (Ve) are dominant, and the latter is homozygous lethal. The genes we and ye showed epistatic interaction, the first with ye, Re, and Ve, and the second with Re. The results of the various crosses suggest that only Ve and ye are linked, so the linkage groups have been designated as A- we, B- Ve-ye, and C- Re. Study of these mutants in A. ludens will serve as the basis for the development of a genetic map for this species. The mutations also will be useful for the development of a genetic-sexing method.
The Natural History and Unusual Mating Behavior ofEuxesta bilimeki(Diptera: Ulidiidae)
Authors: Brunel Odette , Rull Juan
Published: January 2010

We report results of a 2-yr study aimed at describing the natural history and mating behavior of Euxesta bilimeki (Hendel) (Diptera: Ulidiidae) a picture-winged fly species associated with Agave atrovirens Karw. ex Salm-Dyck (Agavaceae) in the Mexican altiplano. The study consisted of direct field observations and a year-long population survey in the field complemented with laboratory experiments and observations. E. bilimeki was found to be multivoltine, able to resist temperatures below freezing during winter, and it developed on rotting agave leaves in large larvalpupal aggregations. Adults fed on carbohydrate and protein sources found on the plant, where they could be sighted all year long. Courtship was based on a sequence of visual and tactile displays that could result in female rejection of courting males. Males constantly harassed females, who mated multiple times, but frequently expelled and consumed ejaculates after mating. We discuss hypotheses on the evolution of this rare behavior and highlight the value of performing descriptive studies on the natural history of poorly known taxonomic groups to foster understanding of the evolution of behavior.
Parathyroid Carcinoma: Current Understanding and New Insights into Gene Expression and Intraoperative Parathyroid Hormone Kinetics
Authors: Abdelgadir Adam Mohamed , Untch Brian R. , Olson John A.
Published: January 2010

Learning Objectives

After completing this course, the reader will be able to: Discuss the association of parathyroid cancers with severe hypercalcemia and markedly elevated parathyroid hormone levels.Describe the effect of the risk factors, clinical presentation, and gene expression on diagnosis of parathyroid cancers.Analyze the probability of cure for parathyroid cancers with treatment by aggressive surgery with en bloc resection and lymph node dissection.

CME This article is available for continuing medical education credit at CME.TheOncologist.com

Parathyroid carcinoma is an indolent but ultimately life-threatening malignancy. Due to the lack of definitive diagnostic markers and overlapping clinical features of benign primary hyperparathyroidism (PHPT), this disease is often misdiagnosed as parathyroid adenoma. Therefore, a high index of suspicion preoperatively and early intraoperative recognition with en bloc surgical resection are crucial for favorable outcome. Owing to the rarity of the disease, little is known about the molecular pathogenesis of parathyroid carcinoma. Here, we review the literature to present current understanding of the disease and provide new information on gene expression and use of intraoperative parathyroid hormone (PTH) monitoring in the surgical management of this rare malignancy. Specifically, using microarray transcriptome analysis of an unequivocal case of parathyroid carcinoma and a biopsy from the same patient's normal parathyroid gland, we identify APP, CDH1, KCNJ16, and UCHL1 as differentially expressed genes in parathyroid carcinoma. Further, using case records from four cases of unequivocal parathyroid carcinoma, we compared intraoperative PTH kinetics of these patients to 475 patients with benign PHPT, and show that intraoperative PTH monitoring is accurate in predicting postoperative normocalcemia in initial en bloc operations for parathyroid carcinoma.
Actors are Skilled in Theory of Mind but Not Empathy
Authors: Goldstein Thalia R. , Wu Katherine , Winner Ellen
Published: January 2010

Actors must imagine themselves in a different world: they must adopt the perspective of multiple characters, grasp their beliefs and intentions, and feel their emotions. In this study we tested the hypothesis that actors have unusually sharp mind-reading abilities and unusually strong empathy. In Study 1, adolescent actors outperformed adolescents without acting experience in their ability to imagine the mental states expressed by pictures of peoples' eyes (a theory of mind measure), but did not excel on empathy as measured by a self-report scale. In Study 2, we replicated these findings with young adults using a different measure of theory of mind. These findings show that adolescent and adult actors are skilled in reading others' mental states, but do not report above average levels of empathy. Thus, strength in theory of mind can exist independently of strength in empathy.
Beyond the Identity Theory
Authors: Brooks Eugene M.
Published: January 2010

Extensions of Lockean and Kantian concepts offer new insights into the neurophysiology of consciousness. The Identity Theory as presented herein is plausible and leads to major revisions in concepts and their terminologies relating to consciousness: Memory items are regarded as semi-independent rather than as only hierarchical. The concept of representations is revised. It can be seen that the exact determination of the physical side of the identity is of secondary importance to the central concept of the Identity Theory. Consciousness and all of reality ultimately consists, in the mind of the individual, of the qualities to which each individual is limited throughout life. Human beings are restricted in principle from learning the specific answers to the “hard problem(s)” of consciousness except, eventually, as correlations. The restriction results from the inability to observe consciousness from either an “inside” or an “outside” perspective. Meaning, which involves a fundamental function of the mind, is described as equivalent to consciousness at the neurophysiological level even though it is different at the semantic level. According to the Identity Theory, neurons or other physical elements are consciousness and meaning.
Modeling of Commercial Ethylene Oxide Reactor: A Hybrid Approach by Artificial Neural Network & Differential Evolution
Authors: Lahiri Sandip K , Khalfe Nadeem
Published: January 2010

This study is motivated by a growing popularity of artificial neural network for process modeling and regression problems. However, many ANN regression application studies are performed by expert' users who have a good understanding of ANN methodology. Since the quality of ANN models depends on a proper setting of ANN architecture and ANN meta-parameters, the main issue for practitioners trying to apply ANN regression is how to set these parameter values (to ensure good generalization performance) for a given data set. Non-expert users face a difficulty in finding an optimum ANN architecture and are often confused about how to choose the ANN meta parameters. The present paper addresses this issue and develops a new hybrid procedure to find the optimum ANN architecture and tunes the ANN parameters, thus relieving the non expert' users. This method incorporates hybrid artificial neural network and differential evolution technique (ANN-DE) for efficient tuning of ANN meta parameters. The algorithm has been applied for modeling of a commercial ethylene oxide (EO) reactor. The model developed through this hybrid algorithm can predict the EO reactor output with only 0.4% error.
6-Lump Kinetic Model for a Commercial Vacuum Gas Oil Hydrocracker
Authors: Sadighi Sepehr , Ahmad Arshad , Seif Mohaddecy S. Reza
Published: January 2010

A 6-lump kinetic model, including a catalyst decay function for hydrocracking of vacuum gas oil in a commercial plant, is proposed. The model considers vacuum gas oil (VGO) and unconverted oil, having boiling point higher than 380-°C (380+°C) as one lump. Other lumps are diesel (260-380-°C), kerosene (150-260-°C), heavy naphtha (90-150-°C), light naphtha (40-90-°C) and gases (40-°C) as products. Initially, a kinetic network with thirty coefficients is considered, but following an evaluation using measured data and order of magnitude analysis, mainly the route passes of converting middle distillates to naphtha lumps are omitted; thus the number of kinetic coefficients is reduced to eighteen. This result is consistent with the reported characteristics of amorphous catalyst, which has the tendency to produce more distillates than naphtha. By using catalyst decay function in the kinetic model and replacing days on stream with a noble term, called accumulated feed, the prediction of the final approach during 1.5 years is in good agreement with the actual commercial data. The average absolute deviation (AAD%) of the model is less than 5% for all main products. If the residue or unconverted VGO is considered, the error only increases to 6.94% which is still acceptable for a commercial model. The results also confirm that the hydrocracking of VGO to upgraded products is represented better by a second order reaction.
Enhancing Stability of an Autonomous Microgrid using a Gain Scheduled Angle Droop Controller with Derivative Feedback
Authors: Majumder Ritwik , Ghosh Arindam , Ledwich Gerard , Zare Firuz
Published: January 2010

This paper discusses the stability of an autonomous microgrid in which, load sharing by a gain scheduled angle droop controller with derivative feedback is proposed. It is assumed that all the DGs are connected through Voltage Source Converter (VSC). The VSCs are controlled by state feedback controller to achieve desired voltage and current outputs that are decided by a droop controller. First a load sharing strategy is derived in terms of droop controller gain and converter output inductance, combining angle droop controller and DC load flow analysis. Then state space models of converters with its associated feedback controller are derived to investigate system stability as a function of the droop controller gain and converter output inductance through eigen value analysis. It is shown that with proposed angle droop controllers, where the droop gains are scheduled based on the output power along with derivative feedback it is possible to achieve a higher stability margin with better load sharing. These observations are then verified through simulation studies using PSCAD/EMTDC. It will be shown that the simulation results closely agree with stability behavior predicted by the eigenvalue analysis.