bluuebunny/crossref_metadata_2025 huggingface dataset:
Phenotypic Conversions of “Protoplasmic” to “Reactive” Astrocytes in Alexander Disease
Authors: Sosunov Alexander A. , Guilfoyle Eileen , Wu Xiaoping , McKhann Guy M. , Goldman James E.
Published: April 2013

Alexander Disease (AxD) is a primary disorder of astrocytes, caused by heterozygous mutations inGFAP, which encodes the major astrocyte intermediate filament protein, glial fibrillary acidic protein (GFAP). Astrocytes in AxD display hypertrophy, massive increases in GFAP, and the accumulation of Rosenthal fibers, cytoplasmic protein inclusions containing GFAP, and small heat shock proteins. To study the effects of GFAP mutations on astrocyte morphology and physiology, we have examined hippocampal astrocytes in three mouse models of AxD, a transgenic line (GFAPTg) in which the normal humanGFAPis expressed in several copies, a knock-in line (Gfap+/R236H) in which one of theGfapgenes bears an R236H mutation, and a mouse derived from the mating of these two lines (GFAPTg;Gfap+/R236H). We report changes in astrocyte phenotype in all lines, with the most severe in theGFAPTg;Gfap+/R236H, resulting in the conversion of protoplasmic astrocytes to cells that have lost their bushy-like morphology because of a reduction of distal fine processes, and become multinucleated and hypertrophic. Astrocytes activate the mTOR cascade, acquire CD44, and lose GLT-1. The altered astrocytes display a microheterogeneity in phenotypes, even neighboring cells. Astrocytes also show diminished glutamate transporter current, are significantly depolarized, and not coupled to adjacent astrocytes. Thus, the accumulation of GFAP in the AxD mouse astrocytes initiates a conversion of normal, protoplasmic astrocytes to astrocytes that display severely “reactive” characteristics, many of which may be detrimental to neighboring neurons and oligodendrocytes.
Signals through the StriatopallidalIndirectPathway Stop Movements by Phasic Excitation in the Substantia Nigra
Authors: Sano Hiromi , Chiken Satomi , Hikida Takatoshi , Kobayashi Kazuto , Nambu Atsushi
Published: April 2013

The striatum and subthalamic nucleus (STN) are the input stations of the basal ganglia and receive excitatory afferents from the cerebral cortex. The basal ganglia control voluntary movements through three parallel pathways mediated by the input stations: thehyperdirectpathway, which conveys direct cortical inputs to the substantia nigra pars reticulata (SNr), the output nucleus, through the STN; thedirectpathway, which arises from striatal neurons expressing dopamine D1 receptors and projects to the SNr; and theindirectpathway, which arises from striatal neurons expressing dopamine D2 receptors (D2Rs) and projects indirectly to the SNr by way of the globus pallidus (GP) and STN. Our previous study showed that immunotoxin-mediated cell targeted ablation of D2R-expressing striatal neurons in mice induced motor hyperactivity. To elucidate the mechanism underlying the hyperactivity, here we examined neuronal activity in the GP and SNr. The ablation of D2R-expressing striatal neurons had little effect on spontaneous activity in the GP and SNr, but induced dramatic changes in the cortically evoked triphasic response composed of early excitation, inhibition, and late excitation in the GP and SNr (i.e., reduced inhibition in the GP, and reduced late excitation in the GP and SNr). In contrast, the ablation of striatal cholinergic interneurons, which also express D2Rs, did not show such effects. Therefore, the reduction of the cortically evoked late excitation in the SNr seems to be responsible for hyperactivity. These observations suggest that phasic late excitation in the SNr through the striatopallidalindirectpathway plays a key role in stopping movements.
Modeling Transformations of Neurodevelopmental Sequences across Mammalian Species
Authors: Workman Alan D. , Charvet Christine J. , Clancy Barbara , Darlington Richard B. , Finlay Barbara L.
Published: April 2013

A general model of neural development is derived to fit 18 mammalian species, including humans, macaques, several rodent species, and six metatherian (marsupial) mammals. The goal of this work is to describe heterochronic changes in brain evolution within its basic developmental allometry, and provide an empirical basis to recognize equivalent maturational states across animals. The empirical data generating the model comprises 271 developmental events, including measures of initial neurogenesis, axon extension, establishment, and refinement of connectivity, as well as later events such as myelin formation, growth of brain volume, and early behavioral milestones, to the third year of human postnatal life. The progress of neural events across species is sufficiently predictable that a single model can be used to predict the timing of all events in all species, with a correlation of modeled values to empirical data of 0.9929. Each species' rate of progress through the event scale, described by a regression equation predicting duration of development in days, is highly correlated with adult brain size. Neural heterochrony can be seen in selective delay of retinogenesis in the cat, associated with greater numbers of rods in its retina, and delay of corticogenesis in all species but rodents and the rabbit, associated with relatively larger cortices in species with delay. Unexpectedly, precocial mammals (those unusually mature at birth) delay the onset of first neurogenesis but then progress rapidly through remaining developmental events.
Zebrafish Calls for Reinterpretation for the Roles of P/Q Calcium Channels in Neuromuscular Transmission
Authors: Wen Hua , Linhoff Michael W. , Hubbard Jeffrey M. , Nelson Nathan R. , Stensland Donald , Dallman Julia , Mandel Gail , Brehm Paul
Published: April 2013

A long-held tenet of neuromuscular transmission is that calcium-dependent neurotransmitter release is mediated by N-type calcium channels in frog but P/Q-type channels in mammals. The N-type assignment in frog is based principally on pharmacological sensitivity to ω-conotoxin GVIA. Our studies show that zebrafish neuromuscular transmission is also sensitive to ω-conotoxin GVIA. However, positional cloning of a mutant line with compromised neuromuscular function identified a mutation in a P/Q- rather than N-type channel. Cloning and heterologous expression of this P/Q-type channel confirmed a block by ω-conotoxin GVIA raising the likelihood that all vertebrates, including frog, use the P/Q-type calcium channel for neuromuscular transmission. In addition, our P/Q defective mutant line offered a means of testing the ability of roscovitine, known to potentiate frog neuromuscular transmission, to mediate behavioral and functional rescue. Acute treatment led to rapid improvement of both, pointing to potential therapeutic benefit for myasthenic disorders involving calcium channel dysfunction.
Black Sheep
Authors: Coluzzi Seth J.
Published: April 2013

Modal theory has been fraught with shortcomings and inconsistencies from the Renaissance to the present, but the Phrygian mode has proven especially problematic, earning a reputation as the unruly black sheep of the modal family. Much of the difficulty stems from the inadequacy of the clausula in mi to serve as an effective terminal cadence, the threat of mi contra fa between scale degrees 5 and 2 (B and F), and the tendency of Phrygian works to prefer the fourth and sixth degrees (A and C) as cadential goals. Although recent studies have attempted to provide nonmodal explanations for the melodic and cadential peculiarities of the Phrygian mode, these efforts have for the most part fallen short of serving as effective, normative theories, leaving instead a gap between music, mode, and model.

The present study examines how the Phrygian mode functions both on the musical surface and on the larger scale in music of the late sixteenth century, showing how a new form of terminal cadence came into widespread practice after 1550 that proved utterly devoid of theoretical grounding. This overview leads to the exposition of a structural model for the Phrygian mode that is both normative within this repertory and accountable to contemporary modal theory. Although analyses of works by Rore, Palestrina, and Wert are used in support of this theoretical model, the main analytical focus is devoted to the madrigals “Tirsi morir volea” (1580) and “Cruda Amarilli, che col nome ancora” (1595) of Luca Marenzio. Based on these examples of Marenzio’s handling of the Phrygian mode, I question the modal designation of one work from Marenzio’s Seventh Book (1595), offering a new explanation for the book’s enigmatic departure from an ordering based on its principal textual source, Guarini’s Il pastor fido.
Historical Mirroring, Mirroring History
Authors: Clausius Katharina
Published: April 2013

Visualizing his interaction with music’s history in Expositions and Developments, Stravinsky enigmatically describes his early neoclassical work Pulcinella as a “look in the mirror.” This spatial account of Pulcinella’s stylistic imitation reflects the crucial visual contribution of Stravinsky’s collaborators Pablo Picasso and Léonide Massine. The ballet’s humorous and playful collaboration among the arts insists on a thoroughly performative neoclassicism; Pulcinella takes neoclassicism’s conceptual negotiation with time and grounds it in the immediate physical spaces of its music, choreography, and set design. Whereas neoclassicism is often theorized as an overt antagonism between present and past, Pulcinella’s visual aesthetic recasts its historicism as a lighthearted dialogue among the various arts. Written in the same decade as Stravinsky’s ballet, Mikhail Bakhtin’s Author and Hero in Aesthetic Activity draws a compelling image of the visual symbiosis between author and work. This appealingly cooperative model, I argue, offers a new philosophical aesthetic for Pulcinella’s interdisciplinary historicism. I take Bakhtin’s concept of authorship as the basis for an appreciation of Pulcinella’s project to reinstate history as an equal, positive collaborator in its neoclassical interaction.
Public Works: NEH, Congress, and the State Humanities Councils
Authors: Zainaldin Jamil
Published: April 2013

The National Foundation on the Arts and Humanities Act of 1965 is the most ambitious piece of cultural legislation in American history. The story of its creation and evolution is a tangled one that continues to the present day. This essay looks at NEH and NEA in their early years, their relations with Congress, and the process by which NEH fostered the invention of humanities-based “State Committees,” significantly different in concept from NEA’s innovation of “State Arts Agencies.” The circumstances that led to the creation of these grassroots programs ultimately changed NEH itself while popularizing the novel terminology and concept of “public” humanities work. The essay concludes with reflections about the time-bound quality of NEH and the State Humanities Councils and considers their sustainability in a new century.
Making the Humanities Public
Authors: Greenfield Briann
Published: April 2013

Connecticut Humanities (CTH), one of the largest and most prosperous state humanities councils in the country, created a model of the public humanities around the production of heritage tourism. State funding for heritage tourism helped CTH develop into a major advocacy organization that has provided funding and capacity building services to the state’s heritage institutions while it also cultivated appreciation and understanding of Connecticut history. But because of state budget deficits and the failure of heritage tourism to sustain the state’s history museums, heritage tourism may no longer offer a viable paradigm and CTH must likely develop a new model of the public humanities that engages more directly with public audiences and a wider variety of humanities organizations.
Imagining the Digital Future of The Public Historian
Authors: Bryans William , Camarillo Albert , Chattopadhyay Swati , Christensen Jon , Leon Sharon , Stanton Cathy
Published: April 2013

The digital revolution has transformed research, exhibition, writing, review, participatory public engagement, and every other aspect of history practice. To consider the influence of these changes on The Public Historian, the journal has solicited the perspectives of six scholars with expertise on digital history to reflect on what the internet age affords TPH as a scholarly journal for the field of public history.
Now You See It, Now You Don’t
Authors: Tiro Karim M.
Published: April 2013

This essay offers a critical overview of War of 1812 commemoration activities during the first year of the war’s bicentennial. Canada and the United States remember the war differently—when they remember it at all. This essay explores the reasons for the conflict’s marginalization, as well as the sharp contrast in interpretation. These include history, geography, nationalism, and politics. Finally, the essay suggests ways in which public history interpretation might be improved in the future.
Linking inflammation and neuroendocrine differentiation: the role of macrophage migration inhibitory factor-mediated signaling in prostate cancer
Authors: Savoy Rosalinda M , Ghosh Paramita M
Published: April 2013

A new paper by Tawadroset al. inEndocrine-Related Cancerdemonstrates a link between macrophage migration inhibitory factor and neuroendocrine differentiation in prostate cancer. This paper may have implications in explaining the effect of prostatitis and chronic inflammation on the development of aggressive prostate cancer.
Incorporation of Luminescent Zinc Oxide Nanoparticles into Polystyrene
Authors: Li Rui , Fern George R. , Withnall Robert , Silver Jack , Bishop Peter , Thiebaut Benedicte
Published: April 2013

Zinc oxide (ZnO) nanoparticles and nanoparticles of luminescent zinc oxide (ZnO:Zn) phosphor were successfully synthesised and well characterised. A transparent polystyrene composite sheet containing ZnO:Zn nanoparticles was prepared by a solvent casting method. The sheet manifested comparable transmission to a virgin polystyrene film due to very uniform dispersion of the ZnO:Zn nanoparticles into the polystyrene. Evidence for uniform dispersion was evident in both its luminescent properties and in a SEM image. The photoluminescent characteristics of the ZnO:Zn, both as a pure powder and embedded in a polystyrene matrix, are reported. The uniformity of the photoluminescence of the composite sheet under near ultraviolet excitation is demonstrated. The luminescent ZnO:Zn nanoparticles are shown to have applications for use not only as an inhibitor of the ultraviolet degradation of polymers, but also for providing polymers with light emitting functionality.
First-Principles Calculation of the Electronic Properties of Single-Walled Carbon Nanotubes under Torsions
Authors: Mihara K. , Shintani K.
Published: April 2013

The structures and electronic properties of single-walled carbon nanotubes (SWNTs) under torsions are investigated using first-principles calculation based on the density functional theory. A SWNT of the chiral indices (5,0) is equilibrated under a torsion, and its equilibrium energy is obtained. It is revealed there is a structure having the minimum energy at a torsion of a specific angle of twist between 0 deg/Å and 1.88 deg/Å. Next, shear deformations corresponding to torsions imposed on the SWNTs of the chiral indices (5,0) and (5,1) are given to graphene sheets, and their energy band structures are calculated. It is concluded their band gaps decrease with the increase of the specific angle of twist.
Highly-Tunable Polymer/CNTs Nanostructures: A Rapid and Facile Approach for Controlled Architecture and Composition
Authors: Mechrez Guy , Suckeveriene Ran Y. , Narkis Moshe , Segal Ester
Published: April 2013

This research presents a new fabrication method for tailoring polymer/carbon nanotubes (CNTs) nanostructures with controlled architecture and composition. The CNTs are finely dispersed in a polymeric latex i.e. polyacrylate, via ultrasonication, followed by a microfiltration process. The later step allows preserving the homogeneous dispersion structure in the resulting solid nanocomposite. The combination of microfiltration and proper choice of the polymer latex allows for the design of complex nanostructures with tunable properties e.g., porosity, mechanical properties. An important attribute of this methodology is the ability to tailor any desired composition of polymer-CNTs systems, i.e., nanotubes content can practically vary anywhere between 0 to 100 wt%. Thus, for the first time a given polymer/CNTs system is studied over the entire CNTs composition, resembling immiscible binary polymer blends. The polymer in these systems exhibits a structural transition from a continuous matrix (nanocomposite) to segregated domains dispersed within a porous CNTs network. An analogy of this structural transition to phase inversion phenomena in immiscible polymer blends is suggested.
Electronic Transport and Doping Effects in Reduced Graphene Oxide Measured by Scanning Probe Microscopy
Authors: Kehayias Christopher E. , MacNaughton Samuel , Sonkusale Sameer , Staii Cristian
Published: April 2013

We present a Scanning Probe Microscopy study of doping and sensing properties of reduced graphene oxide (rGO)-based nanosensors. rGO devices are created by dielectrophoretic assembly of rGO platelets onto interdigitated electrode arrays, which are lithographically pre-patterned on top of SiO2/Si wafers. The availability of several types of oxygen functional groups allows rGO to interact with a wide range of organic dopants, including methanol, ethanol, acetone, and ammonia. We perform sensitive Scanning Kelvin Probe Microscopy (SKPM) measurements on patterned rGO electronic circuits and show that the local electrical potential and charge distribution are significantly changed when the device is exposed to organic dopants. We also demonstrate that SKPM experiments allow us to quantify the amount of charge transferred to the sensor during chemical doping, and to spatially resolve the active sites of the sensor where the doping process takes place.
Impact of photoinduced processes on the plasmonic enhancement of colloidal quantum dot emission
Authors: Sadeghi S. M. , West R. G. , Patty Kira D.
Published: April 2013

We study the mutual effects of photoinduced processes (irradiation effects) and plasmonic emission enhancement in close-packed CdSe/ZnS colloidal quantum dots in the vicinity of gold metallic nanoparticles with two significantly different size distributions. For this we examine the impact of the heat generated by the metallic nanoparticles, the strength of plasmonic field enhancement, and the rate of energy transfer from the quantum dots to metallic nanoparticles in the presence of a laser field with low and moderate intensities. Our results show that the interplay between the photophysics of the quantum dots and their plasmonic emission enhancement is significantly pronounced when the metallic nanoparticles are large. In such a case we observed large suppression of photoinduced fluorescence enhancement (PFE). For smaller metallic nanoparticles the results suggest mostly an overall time-independent suppression of the quantum dots’ emission with no significant impact on PFE.
Disclination Shape Analysis for Nematic Liquid Crystals under Micron-range Capillary Confinement
Authors: Shams Alireza , Yao Xuxia , Park Jung Ok , Srinivasarao Mohan , Rey Alejandro D.
Published: April 2013

Nematic liquid crystals (NLCs) under micron-range confinement exhibit a rich defect phenomenology that can be used to extract elastic (Frank moduli) material parameters of critical importance for next generation electro-optical devices. In this work we develop a model to predict defect-driven textural transformations that arise when a NLC is confined to a circular capillary. In the initial transformation stage an unstable disclination defect of strength +1 nucleates in the axis of the capillary and quickly branches into two stable +1/2 disclination defects. The model includes: (1) the Kirchhoff branch balance equation which predicts the splitting of a +1 into two +1/2 wedge disclinations; (2) the curvature of the +1/2 disclination lines as a function of elastic properties. This model shows that by increasing the ratio of tension strength to bending stiffness, the branch point angle increases, but the final defect distance decreases; and (3) the aperture branching angle of the +1/2 lines as a function of the elastic properties and the magnitude of the curvature at the branch point. These three predictions form the basis for the evaluation of the Frank elastic moduli on NLCs. The key advantage of the implemented methodology is to use time-dependent textural transformations under micron-range capillary confinement to extract elastic parametric data needed to further develop NLCs in functional and structural application.
Thermo-responsive metallo-supramolecular gels based on terpyridine end-functionalized amphiphilic diblock copolymers
Authors: Brassinne Jérémy , Fustin Charles-André , Gohy Jean-François
Published: April 2013

A thermo-responsive hydrogel was prepared on the basis of terpyridine endfunctionalized polystyrene-block-poly(N-isopropylacrylamide) diblock copolymer. As a first level of assembly, the copolymer was dissolved in a selective solvent to yield micelles bearing terpyridine ligands at the extremity of the coronal chains. The second level of self-assembly was triggered upon addition of metal ions to the micellar solution. Mechanical properties of the accordingly obtained micellar gel were finally characterized by rotational rheometry, below and above the lower critical solution temperature.
Pulsed Electron Beam Deposition of Nanocrystalline Diamond
Authors: Henda Redhouane , Alshekhli Omar
Published: April 2013

Pulsed electron beam ablation (15 keV, 1 kA, 100 ns) has been used to grow thin films of nanocrystalline diamond on silicon substrates. The films have been grown at room temperature and 150°C, and under argon as the working background gas at a pressure of about 4 mTorr. Visible reflectance spectroscopic analysis has shown films thickness to range between about 55 nm and 115 nm. Visible-Raman spectroscopic measurements have confirmed the presence of sp3 carbon bonds with a substantial fraction in the deposited films, and surrounded by a graphitic phase. The morphological features of the films have been assessed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The films surface is relatively smooth at room temperature and for low thickness, and becomes rougher at high temperature and for thicker films.
Al-SiC Nanocomposites Produced by Ball Milling and Spark Plasma Sintering
Authors: Picu R.C. , Gracio J.J. , Vincze G.T. , Mathew N. , Schubert T. , Lopez A.B. , Buchheim C.
Published: April 2013

In this work Al-SiC nanocomposites were prepared by high energy ball milling followed by spark plasma sintering of the powder. For this purpose Al micro-powder was mixed with 50 nm diameter SiC nanoparticles. The final composites had grains of approximately 100 nm dimensions, with SiC particles located mostly at grain boundaries. To characterize their mechanical behavior, uniaxial compression, micro- and nano-indentation were performed. Materials with 1vol% SiC as well as nanocrystalline Al produced by the same means with the composite were processed, tested and compared. AA1050 was also considered for reference. It was concluded that the yield stress of the nanocomposite with 1 vol% SiC is 10 times larger than that of regular pure Al (AA1050). Nanocrystalline Al without SiC and processed by the same method has a yield stress 7 times larger than AA1050. Therefore, the largest increase is due to the formation of nanograins, with the SiC particles’ role being primarily that of stabilizing the grains. This was demonstrated by performing annealing experiments at 150°C and 250°C for 2h, in separate experiments.
Study on the photo-transfer thermoluminescence in Eu doped potassium chloride
Authors: Duran-Munoz Hector , Perez-Salas Raul , Piters Thomas
Published: April 2013

In this work a survey of possible optical stimulation processes in irradiated KCl:Eu with a focusing on photo-transfer thermoluminescence (PTTL) effects are shown. For different wavelengths in the range from 180 to 800 nm a cycle of measurements was performed, each comprising of a TL measurement after light irradiation, a TL measurement after beta irradiation for reference purposes and a PTTL measurement. The latter was obtained by applying first a beta irradiation, then a partial readout up to a certain end temperature followed by a monochromatic light irradiation of a specific wavelength and finally a TL measurement. This procedure was repeated for different partial readout end temperatures. From the results the existence of at least four different photo-transfer processes, induced by 310, 245 and 550 nm light are deduced. The photo transfer process induced by an approximate value of 245 nm produced a TL glow peak not seen before in beta or light induced TL. Furthermore it was observed that some of the TL peaks created by light of 240 and 260 nm were strongly sensitized after a beta irradiation and a partial readout.
Single-Mode Superconductivity in LaAlO3/SrTiO3 Nanostructures
Authors: Veazey Joshua P. , Cheng Guanglei , Irvin Patrick , Lu Shicheng , Huang Mengchen , Bi Feng , Bark Chung-Wung , Ryu Sangwoo , Cho Kwang-Hwan , Eom Chang-Beom , Levy Jeremy
Published: April 2013

The properties of superconductors at the extreme limits of dimensionality are of fundamental interest. The interface of LaAlO3 and SrTiO3 hosts a quasi-two-dimensional superconductor below Tc≈200 mK. Here we report superconductivity in nanowire-shaped structures created at the LaAlO3/SrTiO3 interface using conductive atomic force microscope lithography. Nanowire cross-sections are small compared to the superconducting coherence length in LaAlO3/SrTiO3 (w <<ξSC∼100 nm), placing them in the quasi-1D regime. The ability to “write” fully superconducting nanostructures on an insulating LaAlO3/SrTiO3 “canvas” opens possibilities for the development of new families of superconducting nanoelectronics. Four-terminal transport measurements suggest that in some devices both the normal and superconducting states are confined to a single quantum channel.
Dielectric and Piezoelectric Properties of Gd-modified (1-x) BiFeO3-xPbTiO3 Ceramics with a Morphotropic Phase Boundary
Authors: Wang Dalei , Bu Shundong , Jin Guoxi , RuiDai  , Jin Dengren , Cheng Jinrong
Published: April 2013

(1-x)(Bi0.8Gd0.2)FeO3-xPbTiO3 (BGF-PT) solid solutions ceramics of x=0.55,0.50,0.4975, 0.49 and 0.45 were prepared by the mixed oxide method. Gd3+ of 20 at% was introduced into the Bi3+ site to improve the dielectric and piezoelectric properties of BFPT without causing the significant reduction of Curie temperature (Tc). X-ray diffraction analysis shows a transformation from the tetragonal (T) to rhombohedral (R) phase with the increase of BGF content. The morphotropic phase boundary was determined by measuring the dielectric and piezoelectric properties of BGF-PT within a wide composition range. BGF-PT for x=0.4975 shows the coexistence of T and R phases with the dielectric constant and loss of about 895 and 0.031 respectively at the frequency of 102 Hz.
The Role of Defects in Li3ClO Solid Electrolyte: Calculations and Experiments
Authors: Braga M. Helena , Stockhausen Verena , Oliveira Joana C.E. , Ferreira Jorge A.
Published: April 2013

We have analyzed the hopping movement of a new ionic solid electrolyte by calculating defect formation energies and activation barriers. The role of the lattice during diffusion was established. Thermodynamic properties were determined by means of first principles and phonon calculations at working temperatures. The new solid electrolyte, an antiperovskite, Li3-2xMxAO (in which M is a higher valent cation like Ca2+ or Mg2+ and A is a halide like Cl- or Br- or a mixture of halides), was studied either pure or doped. Moreover, we present experimental ionic conductivity data for these novel solid state ionic conductors for the doped and the pure solid electrolyte from room temperature and up to ∼253 °C. In this paper, we compare the ionic conductivity of the latter solid electrolyte with other fast ionic conductors.
Aspectos neurológicos da toxoplasmose adquirida: estudo clínico-laboratorial e terapêutico de 8 casos
Authors: Assis J. Lamartine de , Scaff Milberto , Bacheschi Luiz Alberto
Published: April 2013

Foram revistos 62 casos com o diagnóstico de toxoplasmose, de pacientes internados nas Clínicas Neurológica e de Moléstias infecciosas do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo no período de 1958 a 1968, tendo sido encontrados 8 casos com provável comprometimento do sistema nervoso central pela toxoplasmose adquirida. Baseados nesses casos os autores fizeram um estudo clínico, laboratorial e terapêutico dessa neuroparasitose. Foi salientada a dificuldade do diagnóstico de certeza em virtude das manifestações neurológicas serem variáveis e inespecíficas, e a demonstração do parasito ser muito difícil nas formas nervosas da toxoplasmose adquirida. O diagnóstico foi admitido mediante os dados clínicos e laboratoriais, assim como pelos resultados do tratamento específico. Dentre os exames de laboratório foi salientada a reação de Sabin-Feldman, realizada no soro sangüíneo de todos os pacientes; apenas em dois casos esta reação foi feita no líquido cefalorraqueano; em 5 casos a prova sorológica foi repetida a intervalos variáveis de tempo; em um paciente foram realizadas as provas de imunofluorescência. Também foram valorizadas, para o diagnóstico, oscilações significantes das provas sorológicas. Foi considerada a positividade superior a 1/1000 como o limite de separação entre os casos de toxoplasmose-infecção e aqueles de toxoplasmose-doença. Os aspectos clinico-laboratoriais que fundamentaram o diagnóstico foram comentados e bem assim os métodos terapêuticos aplicados e seus resultados.
Malformações arteriovenosas intracranianas. Diagnóstico e tratamento
Authors: Tenuto Rolando A. , Ricciardi-Cruz Oswaldo , Facure Nubor
Published: April 2013

É relatado o estudo clínico-angiográfico e o tratamento de malformações arteriovenosas intracranianas em 27 casos. O déficit motor, observado em 77% dos casos, relacionava-se às malformações situadas na região rolândica ou adjacências. Hemorragia meníngea ocorreu em 62% dos casos. O estudo angiográfico, mediante exame isolado dos sistemas carotídeos e do sistema vértebro-basilar ou da pan-angiografia cerebral, foi feito em todos os casos, permitindo a visibilização dos vasos nutrientes e da drenagem dessas malformações. O emprego da pan-angiografia cerebral é, sem dúvida, a principal contribuição deste trabalho; o estudo angiográfico dos casos de malformação vascular por meio desse método tem permitido melhor definição radiológica da entidade, assim como rigoroso planejamento cirúrgico. A exérese total da malformação constitui o tratamento de escolha, não sendo justificáveis atualmente operações parciais ou indiretas.
Estudo clínico-eletrencefalográfico longitudinal em pacientes epilépticos tratados com Ro 5-4023
Authors: Lison Michel P. , Fassoni Laertel F.
Published: April 2013

Estudaram-se as modificações do quadro clínico e do quadro eletrencefalográfico em 22 pacientes com manifestações epilépticas diárias (5 com ausências típicas, 3 com crises psicomotoras, 5 com ausências mioclônicas, 1 com mioclonias de ação e 8 com síndrome de Lennox), tratados com 7-nitro-5-(2clorofenil)-3H-1,4 benzodiazepina 2 (1H)-one ou Ro 5-4023. Vinte pacientes tinham sido submetidos a terapêuticas anticonvulsivantes usuais sem resultados apreciáveis. Com o uso de Ro 5-4023 as crises foram controladas desde o primeiro dia em 14 pacientes. Em mais 6 doentes houve redução rápida e significativa da intensidade e da freqüência das crises. Destes, um não mais apresentou manifestações a partir da segunda semana de tratamento. Recidivas parciais ocorreram em 8 pacientes. Destaca-se o amplo campo de ação da droga, que age nas epilepsias generalizadas (ausências típicas e ausências mioclônicas), em epilepsias parciais, particularmente crises psicomotoras da infância com ponta-ondas lentas, nas encefalopatias epilépticas graves da infância, de tipo Lennox, e também em síndrome epiléptico degenerativo. Os efeitos colaterais, presentes em 11 pacientes, foram passageiros em 9. Precipitação de crises generalizadas tônico-clônicas ocorreu em dois pacientes; contudo há indícios que esse fenômeno é mais freqüente com outros derivados benzodiazepínicos. As modificações do EEG incluiram desaparecimento ou diminuição das descargas bilaterais e difusas, espontâneas e/ou desencadeadas pela estimulação luminosa intermitente, aparecimento de ritmos rápidos e difusos, persistência ou aparecimento de anormalidades focais lentas ou de tipo irritativo.
Leptomeningite esporotricótica
Authors: Spina-França A. , Anghinah A. , Souza Haroldo S. A. de , Pérez-Guisasola E. , Fava Netto C.
Published: April 2013

Registro de caso de paciente branco de 22 anos de idade com leptomeningite sub-aguda por Sporotrichum Schenckii tratada com sucesso pela anfotericina-B. O fungo foi isolado mediante cultura do LCR; sua inoculação em testículo de rato determinou quadro histopatológico próprio à esporotricose; a partir da lesão testicular o fungo foi novamente isolado mediante culturas. A reação de fixação do complemento para esporotricose mostrou-se positiva no LCR e no soro do paciente.
Efeitos de derivados benzodiazepines na epilepsia: estudos eletrencefalográficos longitudinais
Authors: Lison Michel Pierre
Published: April 2013

Foram estudadas as modificações do quadro eletrencefalográfico em 24 crianças com manifestações epilépticas diárias, tratadas com derivados da benzodiazepina. O conjunto dos fenômenos eletrencefalográficos observados durante os seguimentos terapêuticos longitudinais traduz uma modificação importante dos mecanismos subcorticais envolvidos na gênese das crises convulsivas e na produção das descargas paroxísticas. Os fatos observados coadunam-se com a teoria de uma ação benzodiazepínica sobre o sistema reticular talâmico inespecífico. A ação benzodiazepínica predomina sobre o sistema de inibição ativo anexo ao sistema de projeção talamocortical. Discute-se ainda se essa ação se faz diretamente, através de formações quimiosensíveis existentes no seio do sistema reticular talâmico e/ou indiretamente, pela depressão de certas estruturas do sistema límbico, modificando desta forma o "feed-back" de importantes circuitos subcorticais que podem influenciar os neurônios centrencefálicos hiperexcitáveis.
Evolução do comportamento e da atividade elétrica cortical do rato com lesões crônicas da formação reticular mesencefálica
Authors: Pereira Walter C. , Rocha Tânia Leme da , Timo-Iaria Cesar
Published: April 2013

Para este trabalho foram utilizados 18 ratos albinos da raça Wistar com lesões eletrolíticas crônicas da formação reticular mesencefálica, sendo 11 unilaterais e 7 bilaterais. Todas as lesões foram suficientemente amplas para interromper completamente o sistema ativador ascendente de uma ou de ambas as metades do mesencéfalo. Aumento da sincronização do eletrocorticograma provocado pelo sono espontâneo foi observado mesmo nos animais com lesão bilateral; este fato fala a favor da existência de mecanismos ativadores corticais situados acima do nível mesencefálico, que são deprimidos durante o sono. Progressivamente observa-se recuperação da atividade elétrica cortical dessincronizada e da atividade motora (comportamentos de alerta e de vigília), tanto nos animais com lesão unilateral como nos com bilateral. Nos primeiros, contudo, a recuperação é mais precoce e rápida. O sono fisiológico se desenvolve com todas as suas fases normais a partir do 4.° ou 5.° dias depois da lesão. A atividade dessincronizada do neocórtex observada durante a fase paradoxal do sono independe de qualquer estrutura em particular existente no tegmento do mesencéfalo.
Efeitos do pentobarbital sódico sobre a atividade elétrica cerebral do rato com lesões da formação reticular mesencefálica
Authors: Pereira Walter C. , Rocha Tania Leme da , Timo-Iaria Cesar
Published: April 2013

Para êste estudo foram empregados 35 ratos da raça Wistar em preparação aguda (24 com lesão bilateral e 11 com lesão unilateral) da formação reticular mesencefálica e 18 preparações crônicas. O método empregado na obtenção das preparações foi descrito em trabalho anterior12. O objetivo desta série de experiências foi o de verificar de que maneira o pentobarbital interfere sobre as características da atividade elétrica cortical após lesão da formação reticular mesencefálica. Para tal, em animais preparados agudamente, foram feitas lesões progressivamente mais extensas e o barbitúrico injetado por via intravenosa em doses crescentes. A fim de testar a integridade do sistema reticular ativador ascendente, além de estímulos dolorosos intensos, aplicávamos pulsos de 5 a 10 V, 100 Hz, e 0,1 ms à formação reticular mesencefálica situada abaixo da região lesada. A ausência de reação de alerta cortical (dessincronização) nos assegurava que tal sistema havia sido lesado completamente. Nas preparações crônicas o pentobarbital era injetado por via intraperitoneal. Dessas experiências concluimos o seguinte: 1. Aumento da sincronização do eletrocorticograma nos animais com lesões parciais ou totais da formação reticular mesencefálica. 2. Depressão acentuada e precoce da atividade elétrica cerebral nos ratos com lesão muito extensa (comprometendo também a porção ventrobasal do tálamo). 3. Isocronismo da atividade elétrica cortical nos dois hemisférios cerebrais. 4. O pentobarbital parece agir tanto sobre os sistemas ativadores como sobre o sincronizador do eletrocorticograma. As doses pequenas deprimem os primeiros, liberando o segundo, enquanto que as maiores bloqueiam também este último. Sòmente doses muito mais altas é que fazem desaparecer totalmente a atividade do córtex cerebral, que se mostra, portanto, mais resistente à ação da droga.
Aneurismas da artéria comunicante anterior: considerações sobre 14 casos operados
Authors: Sampaio Pedro
Published: April 2013

Após algumas considerações sobre a freqüência e o quadro clínico dos aneurismas da artéria comunicante anterior, é relatada a experiência do autor, constante de 14 casos operados: nove pacientes se recuperaram totalmente, um sobreviveu com incapacidade parcial e quatro faleceram. O tratamento cirúrgico, apesar de todos os percalços, é ainda a melhor terapêutica, quando possível. Para a indicação cirúrgica quanto às condições do paciente, foi seguida a classificação de Boterell e col. modificada por Hunt e Hess.
Suscetibilidade biológica do Triatoma sórdida e Triatoma infestans a deltametrina e lambdacyhalotrina em condições de campo
Authors: Diotaiuti Liléia , Pinto Claúdio Texeira
Published: April 2013

No município de Posse-Goiás, foram constituídos três grupos homogêneos de casas borrificadas com deltamethrin 5% - 25mg i.a./m* nas formulações pó molhável e suspensão concentrada, ou lambdacyhalothrin 10% - 30 mg i.a./m² pó molhável, para estudo da suscetibilidade biológica do Triatoma sórdida e do Triatoma infeslans até 360 dias após a borrifação. Dez ninfas de terceiro estádio de cada espécie foram colocadas, por casa, em contato com as paredes por 72 horas, em cones plásticos desenvolvidos pela OMS para testes com mosquitos adultos. Trinta dias após a exposição, anotava-se o número de insetos mortos. Estes testes foram realizados aos 90, 270 e 360 dias após a borrifação das casas. Os resultados revelaram persistência da ação inseticida dos três produtos até a última avaliação realizada, e a igual suscetibilidade do Triatoma sórdida e do Triatoma infestans a todas as formulações.
Infecção experimental de macacos cebus apella sp pelo Trypanosoma cruzi: avaliação clínica, eletrocardiqgráfica e anatomopatológica
Authors: Almeida Eros Antonio de , Navarro Maria Regina , Guariento Maria Elena , Carvalhal Sílvio dos Santos
Published: April 2013

Dos trinta e dois macacos capturados no interior do Estado de São Paulo e mantidos em laboratório em gaiolas individuais (24 a 25 C° e 70% de umidificação) após vários xenodiagnósticos negativos, 12 foram infectados por via intraperitoneal com diferentes cepas de Trypanosoma cruzi, cujas formas tripomastigotas injetadas variaram de 1.10(5) a 5.10(6) Os 20 macacos restantes foram mantidos como controle. No período de 1 a 6 anos tanto os animais inoculados como os não inoculados, foram submetidos axenodiagnóstico e teste soro lógico de aglutinação direta, exame clínico e o eletrocardiograma. Posteriormente os macacos foram necropsiados e todos os órgãos submetidos a exame macro e microscópico. O exame clínico e o eletrocardiograma não revelaram alterações. Dos 12 macacos infectados, 4 apresentaram evidências de infecção ao exame histopatológico: utn com formas amastigotas nos tecidos e 3 com miocardite crônica de grau leve. A parasitemiafoi comprovada em 66,66% dos animais na fase aguda e a sorologia em 91,66% na fase crônica. Concluiu-se que os macacos Cebus não expressaram susceptibilidade ao desenvolvimento das lesões que caracterizam a fase . crônica da doença de Chagas mas poderiam ser usados para manter as cepas de T. cruzi e estudos de pesquisa sorológico a longo termo.
The influence of the regional basic diet from northeast Brazil on health and nutritional conditions of mice infected with Schistosoma mansoni
Authors: Coutinho Eridan M. , Freitas Lucila P.C.G. de , Abath Frederico G.C.
Published: April 2013

Protein nutritionalstatus indicators were studied in weanling albino Swiss mice infected with S. mansoni andfed the Regional Basic Diet (RBD)from Northeast Brazil, a multideficient diet of low-protein content. Each mouse was infected percutaneously with 80 cercariae. The experiment lasted 63 days. The growth curve, food consumption, protein intake, weight gain, Protein Efficiency Ratio (PER) and Net Protein Ratio (NPR) were the parameters investigated. RBD-fed mice showed a marked weight loss, a lower food and protein intake, a slower body weight gain and lower rates of food protein utilization when compared to casein-fed animals. Differences between infected and non-infected mice were not consistent. The present results suggest that the effects of RBD-induced malnutrition on health and nutritional conditions of the mice are more severe than those of Manson's schistosomiasis, in the initial phase of the disease.
Ocorrência de rota vírus e adeno vírus em crianças de até 11 anos de idade sem sintomatologia de diarréia em Goiânia - GO
Authors: Camarota Sandra Cristina T. , Azevedo Marli da Silva P. de , Martins Regina M. B. , Barbosa Aristides J. , Ferreira Júnior Pedro A. , Araújo Sérgio V. de , Cardoso Divina das Dores de Paula
Published: April 2013

Trezentas e oitenta e cinco amostras fecais provenientes de crianças na faixa etária de até 11 anos, sem sintomatologia de diarréia, foram estudadas objetivando-se a detecção de rotavirus. Desta amostragem, 268foram obtidas de crianças habitantes de creches e 117 de crianças atendidas no ambulatório do Hospital Lúcio Rebelo de Goiânia-Goiás. Todas as amostrasforam analisadas através da técnica de eletroforese em gel de poliacrilamida (EGPA- SDS), e 89 foram também analisadas pelo ensaio imunoenzimático adaptado para rotavirus e adenovirus (E1ARA). Rotavirus e adenovirus só foram detectados nas crianças atendidas no ambulatório, num percentual de 1,7% e 1,6% respectivamente, não havendo nenhuma positividade nas crianças de creches. Ambos os vírus ocorrerarh na faixa etária de 1 a 2 anos.
Cromoblastomicose produzida por Fonsecaea pedrosoi no Estado do Maranhão. I - aspectos clínicos, epidemiológicos e evolutivos
Authors: Silva Ana Carla C. Mello e , Serra Neto Artur , Galvão Cloves Eduardo S. , Marques Sirley G. , Saldanha Ana Cristina R. , Silva Conceição de Maria Pedroso e , Fischman Olga , Silva Raimunda Ribeiro da , Costa Maria do Rosário da S. R. , Costa Jackson Maurício Lopes
Published: April 2013

Com o objetivo de verificar o comportamento clínico-epidemiológico da cromoblastomicose no Estado do Maranhão, foi feito um estudo retrospectivo e prospectivo de 13 casos, no serviço de Doenças Infecciosas e Parasitárias do Hospital dos Servidores do Estado do Maranhão no período de nov/88 a julho/91. Para a investigação, foi utilizada uma ficha protocolo com todos os dados necessários para uma análise posterior. Nos casos analisados observou-se maior prevalência na faixa etária entre 50 e 60 anos (46,1%) e do sexo masculino (84,6%). Doze pacientes eram procedentes do Estado do Maranhão, dentre os quais 10 da microrregião da baixada ocidental maranhense. Quanto à profissão, 12 (92,3%) eram lavradores. Na sua maioria apresentavam as lesões nos membros inferiores deforma verrugo- confluentes, cor acastanhada, com prurido. O tempo de evolução variou de 0 a 15 anos em 12 casos (92,3%). Quanto aos aspectos laboratoriais, o exame histológico feito em 12 pacientes, diagnosticando cromoblastomicose em 100% deles e a cultura isolou Fonsecaea pedrosoi em 9 casos (70%). O tratamento realizado em todos os pacientes, com algumas variações foi feito com 5 - fluorocitosina apresentando bons resultados evolutivamente. Constatou-se neste trabalho uma provável zona endêmica de cromoblastomicose na microrregião da baixada ocidental maranhense, até agora desconhecida.
Variação de curta escala temporal de bactérias, plcofltoplâncton e nanoheterótrofos na região de Ubatuba - SP, Brasil
Authors: Mesquita Hilda de Souza Lima , Fernandes Ana Júlia
Published: April 2013

A variação temporal da comunidade microbiana (bactérias, picofitoplâncton total e nanoheterótrofos) nas águas de Ubatuba (23°S 45°W) foi estudada durante um período de 7 dias (de 27/02 a 04/03/1988). As amostras foram obtidas na termoclina, duas vezes ao dia (na estôfa da maré baixa e da maré alta durante o período diurno. A densidade de nanoheterótrofos variou de 0,9 a 3,5 x 10³ cels m-1 apresentando valor médio de 2,3 x 10³ cels m-1. Picofitoplâncton total foi representado principalmente por cianobactérias cocóides e sua denside de variocões de 1,0 a 7,6 x 10(6) cels m-1. O número de bactérias variou de 1,0 a 2,7 x 10 cels m-l . A população bacteriana apresentou um padrão de oscilação defasado em relação a variação das concentrações de CI a. O intervalo de tempo entre os valores máximos de Cl a e as densidades máximas de bactéria foi de aproximadamente 24 horas. No início do período de estudo, a interrelação entre nanoheterótrofos e bactérias-picofitoplâncton foi caracterizada por uma oscilação inversa, sugerindo uma interação predador- presa. A partir do dia 02 de março as 3 populações variaram quase que em fase. As influências das condições meteorológicas, do movimento das marés e da predação por microzooplâncton e metazoários são discutidas. A despeito dos vários fatores que podem afetar as interrelações entre nanoheterótrofos e bactérias- picofitoplâncton parece que o padrão observado não é errático e pode estar expressando uma intensa atividade predatória.
Biological and oceanographic upwelling indicators at Cabo Frio (RJ)
Authors: Moser Gleyci A. O. , Gianesella-Galvão Sônia M. F.
Published: April 2013

Phytoplankton biomass, chemical parameters and hydrology were studied in a transect 101.6 km long off Cabo Frio (RJ), Southeast Brazil, during summer (December 29 to 31, 1991) and winter (June 27 to 30, 1992). Wind induced upwelling events are frequently observed in the area during summer, becoming rare during winter. By the summer cruise a bloom of phytoplankton was observed in surface, close to the coast, with chlorophyll concentrations reaching 25.55 mg Chl-a m-3, uncoupled from the cold, nutrient rich waters of South Atlantic Central Water (SACW), found below 40 m depth. During the winter cruise, the SACW raised at the surface waters in front of Cabo Frio depicting an upwelling event. However, in spite of high surface nitrate concentrations (up to 7.7 f.1M) chlorophyll-a were lower than 2 mg Chl-a m-3. The phytoplankton biomass, meteorological and hydrological data suggest a probable upwelling event immediately before the summer cruise, and an ongoing one during winter time. Cluster analyses and principal component analyses (PCA) were applied to summer and winter data, pointing out multidimensional fronts in the area during both seasons.