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Selected AbstractsComparative Analysis of Indoor Levels of Suspended Particulates and Nitrogen Dioxide a Few Hours later after an Asthmatic AttackCHINESE JOURNAL OF CHEMISTRY, Issue 11 2007Emmanuel Ehiabhi UKPEBOR Abstract Suspended particulates (TSP) and nitrogen dioxide (NO2) are known respiratory irritants linked to asthma aggravation. This pilot study was designed to investigate the role of these pollutants on the frequency of asthmatic attack on two of the inhabitants of a household. The surveillance of TSP and NO2 in this household commenced a few hours later, after one of the occupants suffered an attack. The TSP load determination was done using a High Volume Gravimetric sampler and a light scattering method via a Haz-Dust 10 µm particulate monitor. Palmes Diffusion tubes for NO2 and a portable Crowcon Gasman toxic gas detector were utilized for NO2 screening. In the first day of monitoring in the living room, the in situ particulate sampler (Haz-Dust) recorded a mean TSP level of 26,000 µg·m,3. A confirmatory test with the eight hour average Gravimetric sampler gave 25,833 µg·m,3. With the use of the Gasman toxic gas detector for NO2, the NO2 concentration for the first few hours of sampling was lower than 188 µg·m,3, the detection limit of this instrument. However, the exact NO2 concentrations for the 7 day monitoring after the attack were 27.50 µg·m,3 (kitchen) and 12.03 µg·m,3 (living room) as recorded by the Palmes diffusion tubes. [source] Monastrol, a prototype anti-cancer drug that inhibits a mitotic kinesin, induces rapid bursts of axonal outgrowth from cultured postmitotic neuronsCYTOSKELETON, Issue 1 2004Saad A. Haque Abstract Terminally postmitotic neurons continue to express many of the kinesin-related proteins known to configure microtubules during mitosis. Drugs that inhibit these kinesins are being developed as anti-cancer agents with the hope that they will inhibit proliferation of tumor cells without having adverse effects on the nervous system. The prototype, termed monastrol, inhibits the kinesin known as Eg5, which is essential for maintaining separation of the half-spindles. Eg5 is also highly expressed in neurons, particularly during development. Exposure of cultured sympathetic neurons to monastrol for a few hours increased both the number and the growth rate of the axons. With additional time, the overall lengths of the axons were indistinguishable from controls. Sensory neurons showed a similar short-term increase in axonal growth rate. However, prolonged exposure resulted in shorter axons, suggesting that sensory neurons may be more sensitive to toxic effects of the drug. Nevertheless, the overall health of the cultures was still far more robust than cultures treated with taxol, a drug commonly used for anti-cancer therapy. On the basis of these results, we conclude that Eg5 normally generates forces that oppose axonal growth, presumably by partially suppressing the forward advance of microtubules. We speculate that local regulation of Eg5 could be a means by which neurons coordinate rapid bursts of axonal growth with appropriate environmental cues. The comparatively modest toxic effects on the neurons over time are a hopeful sign for clinicians interested in using anti-Eg5 drugs for cancer therapy. Cell Motil. Cytoskeleton 58:10,16, 2004. © 2004 Wiley-Liss, Inc. [source] Effect of treatment delay upon pulp and periodontal healing of traumatic dental injuries , a review articleDENTAL TRAUMATOLOGY, Issue 3 2002J.O. Andreasen Abstract,,,Based on an analysis of the literature concerning parameters influencing the prognosis of traumatic dental injuries, few studies were found to have examined possible relationships between treatment delay and pulpal and periodontal ligament healing complications. It has been commonly accepted that all injuries should be treated on an emergency basis, for the comfort of the patient and also to reduce wound healing complications. For practical and especially economic reasons, various approaches can be selected to fulfill such a demand, such as acute treatment (i.e. within a few hours), subacute (i.e. within the first 24 h), and delayed (i.e. after the first 24 h). In this survey the consequences of treatment delay on pulpal and periodontal healing have been analyzed for the various dental trauma groups. Applying such a treatment approach to the various types of injuries, the following treatment guidelines can be recommended, based on our present rather limited knowledge of the effect of treatment delay upon wound healing. Crown and crown/root fractures: Subacute or delayed approach. Root fractures: Acute or subacute approach. Alveolar fractures: Acute approach (evidence however questionable). Concussion and subluxation: Subacute approach. Extrusion and lateral luxation: Acute or subacute approach (evidence however questionable). Intrusion: Subacute approach (evidence however questionable). Avulsion: If the tooth is not replanted at the time of injury, acute approach; otherwise subacute. Primary tooth injury: Subacute approach, unless the primary tooth is displaced into the follicle of the permanent tooth or occlusal problems are present; in the latter instances, an acute approach should be chosen. These treatment guidelines are based on very limited evidence from the literature and should be revised as soon as more evidence about the effect of treatment delay becomes available. [source] Glutamate drives the touch response through a rostral loop in the spinal cord of zebrafish embryosDEVELOPMENTAL NEUROBIOLOGY, Issue 12 2009Thomas Pietri Abstract Characterizing connectivity in the spinal cord of zebrafish embryos is not only prerequisite to understanding the development of locomotion, but is also necessary for maximizing the potential of genetic studies of circuit formation in this model system. During their first day of development, zebrafish embryos show two simple motor behaviors. First, they coil their trunks spontaneously, and a few hours later they start responding to touch with contralateral coils. These behaviors are contemporaneous until spontaneous coils become infrequent by 30 h. Glutamatergic neurons are distributed throughout the embryonic spinal cord, but their contribution to these early motor behaviors in immature zebrafish is still unclear. We demonstrate that the kinetics of spontaneous coiling and touch-evoked responses show distinct developmental time courses and that the touch response is dependent on AMPA-type glutamate receptor activation. Transection experiments suggest that the circuits required for touch-evoked responses are confined to the spinal cord and that only the most rostral part of the spinal cord is sufficient for triggering the full response. This rostral sensory connection is presumably established via CoPA interneurons, as they project to the rostral spinal cord. Electrophysiological analysis demonstrates that these neurons receive short latency AMPA-type glutamatergic inputs in response to ipsilateral tactile stimuli. We conclude that touch responses in early embryonic zebrafish arise only after glutamatergic synapses connect sensory neurons and interneurons to the contralateral motor network via a rostral loop. This helps define an elementary circuit that is modified by the addition of sensory inputs, resulting in behavioral transformation. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 2009 [source] Electrochemically Functionalized Single-Walled Carbon Nanotube Gas SensorELECTROANALYSIS, Issue 12 2006Ting Zhang Abstract We demonstrate a facile fabrication method to make chemical gas sensors using single-walled carbon nanotubes (SWNT) electrochemically functionalized with polyaniline (PANI). The potential advantage of this method is to enable targeted functionalization with different materials to allow for creation of high-density individually addressable nanosensor arrays. PANI-SWNT network based sensors were tested for on-line monitoring of ammonia gas. The results show a superior sensitivity of 2.44% ,R/R per ppmv NH3 (which is more than 60 times higher than intrinsic SWNT based sensors), a detection limit as low as 50,ppbv, and good reproducibility upon repeated exposure to 10,ppmv NH3. The typical response time of the sensors at room temperature is on the order of minutes and the recovery time is a few hours. Higher sensitivities were observed at lower temperatures. These results indicate that electrochemical functionalization of SWNTs provides a promising new method of creating highly advanced nanosensors with improved sensitivity, detection limit, and reproducibility. [source] Induction of rapid, activity-dependent neuronal,glial remodelling in the adult rat hypothalamus in vitroEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2003Sarah L. Langle Abstract The hypothalamic oxytocinergic system offers a remarkable model of morphological plasticity in the adult because its neurons and astrocytes undergo mutual remodelling in relation to differing physiological conditions. Among various factors involved in such plasticity, oxytocin (OT) itself appears of primary importance as its central administration resulted in morphological changes similar to those brought on by physiological stimuli. In the present study, we applied OT on acute hypothalamic slices from adult rats that included the supraoptic nucleus. Using ultrastructural morphometric analyses, we found that it induced a significant reduction of astrocytic coverage of OT neurons, leaving their surfaces directly juxtaposed, to an extent similar to that detected in vivo under conditions like lactation. These neuronal,glial changes were rapid and reversible, occurring within a few hours, and specifically mediated via OT receptors. They were potentiated by oestrogen and depended on calcium mobilization and de novo protein synthesis. Moreover, they depended on concurrent neuronal activation brought on by hyperosmotic stimulation or blockade of inhibitory GABAergic neurotransmission; they were inhibited by blockade of glutamatergic receptors. Taken together, our observations show that intrahypothalamic release of OT affects not only neuronal activation of the OT system but its morphological plasticity as well. Moreover, the activity dependence of the OT-induced changes strongly suggests that astrocytes can sense the level of activity of adjacent neurons and/or afferent input and this can subsequently act as a signal to bring on the neuronal and glial conformational changes. [source] Controllable Shifts in Threshold Voltage of Top-Gate Polymer Field-Effect Transistors for Applications in Organic Nano Floating Gate MemoryADVANCED FUNCTIONAL MATERIALS, Issue 2 2010Kang-Jun Baeg Abstract Organic field-effect transistor (FET) memory is an emerging technology with the potential to realize light-weight, low-cost, flexible charge storage media. Here, solution-processed poly[9,9-dioctylfluorenyl-2,7-diyl]-co-(bithiophene)] (F8T2) nano floating gate memory (NFGM) with a top-gate/bottom-contact device configuration is reported. A reversible shift in the threshold voltage (VTh) and reliable memory characteristics was achieved by the incorporation of thin Au nanoparticles (NPs) as charge storage sites for negative charges (electrons) at the interface between polystyrene and cross-linked poly(4-vinylphenol). The F8T2 NFGM showed relatively high field-effect mobility (µFET) (0.02,cm2 V,1 s,1) for an amorphous semiconducting polymer with a large memory window (ca. 30,V), a high on/off ratio (more than 104) during writing and erasing with an operation voltage of 80,V of gate bias in a relatively short timescale (less than 1,s), and a retention time of a few hours. This top-gated polymer NFGM could be used as an organic transistor memory element for organic flash memory. [source] Archetype Cationic Iridium Complexes and Their Use in Solid-State Light-Emitting Electrochemical CellsADVANCED FUNCTIONAL MATERIALS, Issue 21 2009Rubén D. Costa Abstract The archetype ionic transition-metal complexes (iTMCs) [Ir(ppy)2(bpy)][PF6] and [Ir(ppy)2(phen)][PF6], where Hppy,=,2-phenylpyridine, bpy,=,2,2,-bipyridine, and phen,=,1,10-phenanthroline, are used as the primary active components in light-emitting electrochemical cells (LECs). Solution and solid-state photophysical properties are reported for both complexes and are interpreted with the help of density functional theory calculations. LEC devices based on these archetype complexes exhibit long turn-on times (70 and 160,h, respectively) and low external quantum efficiencies (,2%) when the complex is used as a pure film. The long turn-on times are attributed to the low mobility of the counterions. The performance of the devices dramatically improves when small amounts of ionic liquids (ILs) are added to the Ir-iTMC: the turn-on time improves drastically (from hours to minutes) and the device current and power efficiency increase by almost one order of magnitude. However, the improvement of the turn-on time is unfortunately accompanied by a decrease in the stability of the device from 700 h to a few hours. After a careful study of the Ir-iTMC:IL molar ratios, an optimum between turn-on time and stability is found at a ratio of 4:1. The performance of the optimized devices using these rather simple complexes is among the best reported to date. This holds great promise for devices that use specially-designed iTMCs and demonstrates the prospect for LECs as low-cost light sources. [source] The Design and Realization of Flexible, Long-Lived Light-Emitting Electrochemical CellsADVANCED FUNCTIONAL MATERIALS, Issue 16 2009Junfeng Fang Abstract Polymer light-emitting electrochemical cells (LECs) offer an attractive opportunity for low-cost production of functional devices in flexible and large-area configurations, but the critical drawback in comparison to competing light-emission technologies is a limited operational lifetime. Here, it is demonstrated that it is possible to improve the lifetime by straightforward and motivated means from a typical value of a few hours to more than one month of uninterrupted operation at significant brightness (>100,cd m,2) and relatively high power conversion efficiency (2 lm W,1 for orange-red emission). Specifically, by optimizing the composition of the active material and by employing an appropriate operational protocol, a desired doping structure is designed and detrimental chemical and electrochemical side reactions are identified and minimized. Moreover, the first functional flexible LEC with a similar promising device performance is demonstrated. [source] Embryo of an annual fish (Austrolebias charrua) in the last dormancy stage, diapause IIIGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 1 2009Article first published online: 22 JAN 200 Embryo of an annual fish (Austrolebias charrua) in the last dormancy stage, diapause III. The embryo, surrounded by a transparent vitelline envelope, is in the pre-hatching stage. A prominent eye and part of the pigmented body and tail are apparent. Why annual fishes? Annual fishes (Order Cyprinodontiformes) are a special kind of teleost, found in Africa and South America, with developmental strategies closely related to their life cycle. These fishes inhabit temporary pools that undergo drying during summer, when all adults die. The embryos remain buried in the bottom mud and are resistant to desiccation. In the subsequent rainy season they hatch a few hours after the pool is flooded and a new reproductive cycle begins. This developmental pattern is characterized by the presence of a unique stage between cleavage and embryogenesis, dispersion-aggregation of blastomeres and because the embryos show reversible developmental arrests (diapauses) at different stages. Annual fish embryos are transparent, large, hardy and easy to maintain in the laboratory. Adults show continuous production of eggs and juveniles reach sexual maturity a few weeks after hatching (an unusual condition in fishes). Their particular developmental features confer unique opportunities for research on cell behavior during early development, the effect of environmental factors on development, the regulation of diapauses and the mechanisms involved in sex determination, among others topics. Image provided by Nibia Berois, Universidad de la República, Montevideo, Uruguay. [source] Photocleavage of Peptides and Oligodeoxynucleotides Carrying 2-Nitrobenzyl GroupsHELVETICA CHIMICA ACTA, Issue 4 2009Roger Ramos Abstract Peptides and oligodeoxynucleotides containing photolabile 2-nitrobenzyl groups as mid-sequences were prepared. Photocleavage of aqueous solutions of these compounds neared completion within 30,min to a few hours depending on the photolabile group used. A photolabile group was introduced in the loop of an intramolecular oligodeoxynucleotide hairpin. Melting curves of the hairpin with and without the complementary oligodeoxynucleotide showed a preference for the intramolecular hairpin form, but an intermolecular duplex was observed after photolysis. These results open the possibility of using photolabile DNA hairpins for the fabrication of patterned surfaces. [source] Neural Signal Manager: a collection of classical and innovative tools for multi-channel spike train analysisINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 11 2009Antonio Novellino Abstract Recent developments in the neuroengineering field and the widespread use of the micro electrode arrays (MEAs) for electrophysiological investigations made available new approaches for studying the dynamics of dissociated neuronal networks as well as acute/organotypic slices maintained ex vivo. Importantly, the extraction of relevant parameters from these neural populations is likely to involve long-term measurements, lasting from a few hours to entire days. The processing of huge amounts of electrophysiological data, in terms of computational time and automation of the procedures, is actually one of the major bottlenecks for both in vivo and in vitro recordings. In this paper we present a collection of algorithms implemented within a new software package, named the Neural Signal Manager (NSM), aimed at analyzing a huge quantity of data recorded by means of MEAs in a fast and efficient way. The NSM offers different approaches for both spike and burst analysis, and integrates state-of-the-art statistical algorithms, such as the inter-spike interval histogram or the post stimulus time histogram, with some recent ones, such as the burst detection and its related statistics. In order to show the potentialities of the software, the application of the developed algorithms to a set of spontaneous activity recordings from dissociated cultures at different ages is presented in the Results section. Copyright © 2008 John Wiley & Sons, Ltd. [source] Growth factors in periodontal regenerationINTERNATIONAL JOURNAL OF DENTAL HYGIENE, Issue 2 2009S Raja Abstract:, Inflammatory periodontal disease is an almost ubiquitous disorder in the adult population. Cases or sites with moderate to advanced disease often continue to show signs of inflammation after non-surgical approach. Our current understanding of periodontal healing is based on a hypothesis by Melcher who proposed that the cell type that repopulates the exposed root surface at the periodontal repair site will define the nature of the attachment/repair that take place. If mesenchymal cells from periodontal ligament/perivascular region of the bone proliferate and colonize the root surface, regeneration occurs. Growth factors are natural cell products that are released or activated when cell division is needed. This action typically occurs during such events as wound healing or tissue regeneration. Activated platelets at the wound margins release several growth factors such as platelet-derived growth factor (PDGF), transforming growth factor (TGF)-,, epidermal growth factor etc. Cells adjacent to the injured site also are induced to release growth factors such as insulin-like growth factor-I, PDGF, TGF-, and TGF-, within a few hours after injury. In periodontal regeneration, the coronal re-establishment of the periodontal ligament (PDL) is required together with corresponding cementum and supporting alveolar bone. Thus, agents which promote periodontal ligament fibroblast (PLF) proliferation and migration as well as collagen biosynthesis would appear to be mediators for enhancing new PDL formation. When combinations or cocktails of different factors are used, greater repair is achieved than when individual factors are applied. [source] Bullous variant of Sweet's syndromeINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 11 2005Susanne Voelter-Mahlknecht MD A 69-year-old woman presented to our clinic as an emergency with erythematous, well-circumscribed plaques, which were partly vesicular, on her extremities and in her armpits, and additionally hemorrhagic blisters on both her palms and her fingers (Fig. 1a), which had developed 2 days after the first appearance of the skin lesions. The rapid onset of the lesions (within a few hours) and the pain associated with them were extremely troublesome to the patient. On admission she complained of fever, tiredness and being easily fatigued. Because of a urinary tract infection 1 month prior to admission, trospiumchloride was given. On clinical examination, body temperature was found to be above 38 °C and infraclavicular lymph nodes were enlarged but not tender. Figure 1. (a) Bullae on the patient's right hand. (b) Multiple partly confluent vesicles with neutrophilic granulocytes intraepidermally and a dense interstitial perivascular infiltration of neutrophilic granulocytes and lymphomononuclear cells (H&E, ×200) Normal or negative laboratory tests included blood counts, liver and kidney parameters, electrolytes and infection screen. Laboratory examination demonstrated minor leukocytosis and absolute neutrophilia (white blood cell count 10 440 cells/µL, neutrophils 8030 cells/µL). X-ray screening, abdominal ultrasound and laboratory investigations were all normal. There was no response to antibiotics when erythromycine was given. However, there was a good response to systemic corticosteroids. The patient was treated with a low dosage of prednisolone, beginning at 50 mg/day, which was then tapered off. Skin lesions resolved within 7 days. Histology from a lesion on the patient's left forearm showed a dense interstitial inflammatory infiltration consisting predominantly of neutrophilic granulocytes from the subepidermal layer to the middle of the reticular dermis. Inflammatory cells penetrated into both blood vessels and vessel walls; vasculitis was not prominent. In the lower dermis, perivascular infiltrations of lymphomononuclear cells were found. In addition, intraepidermally multiple partly confluent vesicles, with inclusions of neutrophilic granulocytes, were found, confirming the diagnosis of this rare variant of an acute febrile neutrophilic dermatosis (Fig. 1b). [source] Long time investigation of the effect of fouling on the super-heaters in a circulating fluidized biomass boilerINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 13 2006Jan Sandberg Abstract The present investigation involves measurements and theories on the mechanisms of the forming of deposit layers on super-heater tubes in a biomass-fired CFD boiler. The deposit layer thickness and the soot-blowing frequency effect on the super-heaters heat transfer are the main subject of the study that has been conducted over a 3-year period. The measurements show a deposit growth rate on the super-heaters of approximately 4 g m,2 h,1. The distribution of the deposit material varies significantly between the windward and the leeward side of the tubes, with the thickest layers on the windward side. Further down stream of the first super-heater, the fouling problem on the super-heater and re-heater tubes are not so severe. A theoretical model shows that a deposit layer of 20 mm will decrease the heat transfer rate of the first super-heater by nearly 40%. The soot-blowing system shows a strong positive effect on the heat transfer rate of the super-heater a few hours after a soot-blowing sequence has been completed. However in the long run, the varied soot-blowing frequency does not have a significant influence on the deposit layer growth rate. Copyright © 2006 John Wiley & Sons, Ltd. [source] Pool boiling on a superhydrophilic surfaceINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 2 2003Y. Takata Abstract Titanium Dioxide, TiO2, is a photocatalyst with a unique characteristic. A surface coated with TiO2 exhibits an extremely high affinity for water when exposed to UV light and the contact angle decreases nearly to zero. Inversely, the contact angle increases when the surface is shielded from UV. This superhydrophilic nature gives a self-cleaning effect to the coated surface and has already been applied to some construction materials, car coatings and so on. We applied this property to the enhancement of boiling heat transfer. An experiment involving the pool boiling of pure water has been performed to make clear the effect of high wettability on heat transfer characteristics. The heat transfer surface is a vertical copper cylinder of 17 mm in diameter and the measurement has been done at saturated temperature and in a steady state. Both TiO2 -coated and non-coated surfaces were used for comparison. In the case of the TiO2 -coated surface, it is exposed to UV light for a few hours before experiment and it is found that the maximum heat flux (CHF) is about two times larger than that of the uncoated surface. The temperature at minimum heat flux (MHF) for the superhydrophilic surface is higher by 100 K than that for the normal one. The superhydrophilic surface can be an ideal heat transfer surface. Copyright © 2002 John Wiley & Sons, Ltd. [source] Application of harmonic radar technology to monitor tree snail dispersalINVERTEBRATE BIOLOGY, Issue 1 2009Kevin T. Hall Abstract. Planned conservation efforts for tree snails of the endangered genus Achatinella, endemic to the island of O'ahu, Hawai'i, will include translocations among the remaining wild and captive-bred populations. In order to establish optimal levels of artificial migration among neighboring groups of snails within fragmented populations, efforts to determine natural dispersal rates through direct observation were initiated. Capture,mark,recapture (CMR) efforts have proved inadequate for obtaining the requisite dispersal estimates, due to low recapture probabilities. In addition, snail dispersal beyond the boundaries of a finite CMR study site was indistinguishable from mortality. In the preliminary study reported here, both the low recapture probability and dispersal detection problems of past CMR efforts were addressed by using harmonic radar tracking. This approach yielded rough dispersal estimates that were unattainable using CMR alone by providing 100% recapture rates even beyond the normal survey area boundaries. Extensive snail movements within clusters of connected trees were frequently observed after tracking for merely a few hours, although movements between unconnected trees were rare and recorded only after monthly survey intervals. Just 11 out of 40 tracked snails made between-tree movements (average distance of 4.94±1.52 m) during the entire 7-month study, and provided the only data utilizable for inferring gene flow in and out of subpopulations. Meteorological data loggers were deployed when tracking began to look for an association between such snail movement and weather fluctuations. The resultant data indicate that increases in both wind gusts and humidity facilitate dispersal (R2=0.77, p-value <0.001), and that passive wind dispersal alone may be responsible for many snail movements (R2=0.59, p-value=0.0014). Despite having provided coarse estimates of short-term dispersal and corresponding wind influences, the limitations of the radar method can be substantial. [source] NBT-PABA test to assess efficiency and kinetics of substituted proteolytic enzyme action in pancreatic duct ligated minipigs,JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 3 2008A. Mößeler Summary The NBT-PABA test is an established method for diagnosis of pancreatic exocrine insufficiency. In the present study the NBT-PABA test was used to test and compare the efficacy of two multienzyme preparations (product A and B) differing in galenic preparation in minipigs in which pancreatic exocrine insufficiency (PEI) was induced by pancreatic duct ligation. Without enzyme substitution no distinct increase in PABA was found in blood after oral administration of NBT-PABA. Administration of both enzyme preparations led to a clear dose dependent rise in PABA-concentrations in blood. Interestingly, the two preparations showed different time curves of serum PABA concentration, indicating differences in the kinetic of proteolytic enzyme action. It is concluded that the NBT-PABA test can be a very useful test for indirectly evaluating proteolytic enzyme efficacy in vivo, and also gives information about the kinetics of enzyme action, not only the end-result of enzyme action (like digestibility trials which were used traditionally). A single test is performed in a few hours and there is no need for fistulated animals. [source] High-temperature (1500,K) reciprocal space mapping on a laboratory X-ray diffractometerJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 2 2007R. Guinebretière A laboratory X-ray diffractometer devoted to the in situ characterization of the microstructure of epitaxic thin films at temperatures up to 1500,K has been developed. The sample holder was built using refractory materials, and a high-accuracy translation stage allows correction of the dilatation of both the sample and the sample holder. The samples are oriented with respect to the primary beam with two orthogonal rotations allowing the registration of symmetric as well as asymmetric reciprocal space maps (RSMs). The association of a monochromatic primary beam and a position-sensitive detector allows the measurement of RSMs in a few minutes for single crystals and in a few hours for imperfect epitaxic thin films. A detailed description of the setup is given and its potential is illustrated by high-temperature RSM experiments performed on yttria-doped zirconia epitaxic thin films grown on sapphire substrates. [source] Effect of Fracture on Bone Turnover Markers: A Longitudinal Study Comparing Marker Levels Before and After Injury in 113 Elderly Women,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 8 2007Kaisa K Ivaska PhD Abstract In this longitudinal, prospective, and population-based study (n = 1044), seven BTMs were assessed before and after trauma in 113 elderly women (85 with fractures). Markers were not altered in the immediate postfracture period but were clearly elevated during fracture repair. Recent fracture should thus be taken into account when markers are used in clinical practice. Introduction: Fracture may influence the levels of bone turnover markers (BTM) and have implications for their use in clinical practice. In this longitudinal, prospective, and population-based study, we assessed prefracture levels of BTMs and compared them with postfracture levels of the same individuals immediately after fracture and during fracture repair. This is the first study in which the effect of fracture on bone markers has been evaluated with prefracture samples available. Materials and Methods: Serum and urine were collected at the emergency unit from 85 women (77.9 ± 1.8 yr) who sustained a fracture after low-energy trauma and 28 controls (77.8 ± 2.0 yr) with similar trauma but no fracture. All were participants of the Malmö OPRA study (n = 1044), and pretrauma samples were collected 1.05 ± 0.85 yr before. Bone turnover was assessed by seven different BTMs reflecting different stages of bone metabolism {C-terminal cross-linked telopeptides of type I collagen [S-CTX], S-TRACP5b, N-terminal propeptides of type I collagen [S-PINP], serum osteocalcin (S-OC[1,49] and S-TotalOC), urinary deoxypyridinoline [U-DPD], and urinary osteocalcin [U-OC]}. Results: BTMs sampled within a few hours after fracture were not altered from preinjury levels. Both bone formation and bone resorption markers were, however, significantly increased 4 mo after fracture. The elevation was most pronounced after hip fracture. Bone turnover remained elevated up to 12 mo after fracture. Conclusions: We believe this study extends our knowledge on the skeletal postfracture metabolic processes. In addition, it may provide a basis for future means to monitor pharmacological intervention promoting fracture healing. [source] Mechanical Prosthetic Valve Dysfunction Causing Pulsus Alternans Leading to Intermittent Electromechanical Dissociation: A Case Report and Literature ReviewJOURNAL OF CARDIAC SURGERY, Issue 6 2007Vasha Kaur M.B.Ch.B. (Hons) She initially developed pulsus alternans which led, over a few hours, to intermittent electromechanical dissociation. Clinical and echocardiographic findings are described. Emergency surgical intervention revealed a piece of chorda wedged between the disc occluder and the valve ring. This case illustrates clinical and Doppler echocardiographic features associated with a rare presentation of an unusual perioperative complication of prosthetic mitral valve dysfunction. We have also included a brief review of related literature. [source] Early homing of adult mesenchymal stem cells in normal and infarcted isolated beating heartsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 2 2008Claudia Penna Abstract Little is known on the early homing features of transplanted mesenchymal stem cells (MSCs). We used the isolated rat heart model to study the homing of MSCs injected in the ventricular wall of a beating heart. In this model all types of cells and matrix elements with their interactions are represented, while external interferences by endothelial/neutrophil interaction and neurohormonal factors are excluded. We studied the morphology and marker expression of MSCs implanted in normal hearts and in the border-zone of infarcted myocardium. Early morphological adaptation of MSC homing differs between normal and infarcted hearts over the first 6 hrs after transplantation. In normal hearts, MSCs migrate very early through the interstitial milieu and begin to show morphological changes. Yet, in infarcted hearts MSCs remain in the site of injection forming clusters of round-shaped cells in the border-zone of the infarcted area. Both in normal and infarcted hearts, immuno-histochemistry and confocal imaging showed that, besides the proliferative marker proliferating cell nuclear agent (PCNA), some transplanted cells early express myoblastic maker GATA-4, and some of them show a VWF immunopositivity. Moreover, a few hours after injection connexin-43 is well evident between cardiomy-ocytes and injected cells. This study indicates for the first time that the isolated beating heart is a good model to study early features of MSC homing without external interferences. The results show (i) that MSCs start to change marker expression few hours after injection into a beating heart and (ii) that infarcted myocardium influences transplanted MSC morphology and mobility within the heart. [source] Subcellular localization and phosphorylation of antizyme 2JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 4 2009Noriyuki Murai Abstract Antizymes (AZs) are polyamine-induced proteins that negatively regulate cellular polyamine synthesis and uptake. Three antizyme isoforms are conserved among mammals. AZ1 and AZ2 have a broad tissue distribution, while AZ3 is testis specific. Both AZ1 and AZ2 inhibit ornithine decarboxylase (ODC) activity by binding to ODC monomer and target it to the 26S proteasome at least in vivo. Both also inhibit extra-cellular polyamine uptake. Despite their being indistinguishable by these criteria, we show here using enhanced green fluorescent protein (EGFP)-AZ2 fusion protein that in mammalian cells, the subcellular location of AZ2 is mainly in the nucleus, and is different from that of AZ1. The C-terminal part of AZ2 is necessary for the nuclear distribution. Within a few hours, a shift in the distribution of EGFP-AZ2 fusion protein from cytoplasm to the nucleus or from nucleus to cytoplasm is observable in NIH3T3 cells. In addition, we found that in cells a majority of AZ2, but not AZ1, is phosphorylated at Ser-186, likely by protein kinase CK2. There may be a specific function of AZ2 in the nucleus. J. Cell. Biochem. 108: 1012,1021, 2009. © 2009 Wiley-Liss, Inc. [source] Case study of a one-sided attack by multiple troop members on a nontroop adolescent male and the death of Japanese macaques (Macaca fuscata)AGGRESSIVE BEHAVIOR, Issue 4 2009Masaki Shimada Abstract An adolescent wild male Japanese macaque (Macaca fuscata), following Kinkazan A troop, was attacked one-sidedly by multiple members of the troop. The victim was identified as PI, and was estimated to be seven±one year old. The aggressive interaction was recorded by video camera until the end. Although at least 16 troop members approached PI more than once, only three males (one adult, two adolescents) of A troop attacked him. PI kept crouching throughout the attack, then escaped to the shore and dived into the sea. The interaction continued for more than one hour. PI was found dead a few hours after the end of interaction. The damage caused by the assailants was not the direct cause of PI's death; it was due to hypothermia caused by drifting in the sea. PI's life history was reconstructed from past records. PI was a normal adolescent male who migrated from an all-male group around B1 troop and started ranging around A troop. The aggressive interaction is believed to be a typical example of conflict between troop males and a nontroop male. The interaction period was very long compared with previous reports on such conflicts among Japanese macaques. PI kept crouching in open areas, exposing himself as a potential competitor for the resources of the troop, and did not show any submissive or reconciliatory behavior toward the troop males. This may be why the troop males did not stop the attack. Aggr. Behav. 35:334,341, 2009. © 2009 Wiley-Liss, Inc. [source] Recruitment of Anguilla spp. glass eels in the Waikato River, New Zealand.JOURNAL OF FISH BIOLOGY, Issue 9 2009Evidence of declining migrations? The timing of Anguilla spp. glass eel recruitment into the Waikato River, North Island, New Zealand, was studied over a 2 year period (2004,2005). While glass eels of both the shortfin eel Anguilla australis and the endemic longfin eel Anguilla dieffenbachii were caught, the former comprised >97% of the species composition. There was a positive correlation of glass eel migrations with spring tides, with peak migration periods typically occurring within a few hours of the peak of high tide, and between 2 and 4 days after the day of spring tide. Both water temperature and discharge had significant inverse relationships with glass eel catches, with temperature explaining >30% of the variance in catch periodicity. Comparison of catch data 30 years apart showed that main migration periods appear to occur several weeks earlier today than previously. Reduced catch per unit effort and duration of runs from recent years' sampling (compared with the 1970s) indicate that a reduction in recruitment may also have occurred during this period, something recorded in other temperate species of Anguilla. [source] Sibling cannibalism in dorada under experimental conditions.JOURNAL OF FISH BIOLOGY, Issue 4 2000II. Effect of initial size heterogeneity, light regime on early cannibalism Cannibalism among embryos and larvae of Brycon moorei (Characidae) occurs during daytime and night-time, and persists under permanent darkness. Embryos and larvae of dorada-provisioned with formulated feed over the first week of exogenous feeding did not survive, except for those exerting cannibalism. When offered alternative fish prey [embryos of Prochilodus magdalenae (0·5,0·8 mg) and Oreochromis niloticus (9,10 mg)], 1-day-old embryos of dorada preferred preying on these, thereby reducing early cannibalism. However, this promoted depensatory growth and more intense cannibalism later in the larval stage. Dorada provisioned with Artemia nauplii in excess showed more homogeneous growth and higher survival, most cannibalistic acts being restricted to the first 24 h of exogenous feeding, just after oral teeth were fully developed (21 h after hatching). Provisioning dorada with Artemia nauplii a few hours before their oral teeth were fully developed reduced early cannibalism from 41 to 15%. High proportions of deformed fish caused higher mortality, both directly and indirectly, as they promoted early cannibalism, depensatory growth and more intense cannibalism among larvae. The initial sorting of embryos, based on their occupation of the water column improved survival significantly during the first week of exogenous feeding, up to 52% in progenies containing <10% of deformed fish. Size-grading of larvae and young juveniles over the next 2 weeks reduced cannibalism to 2·6 and 1·9% day,, in the first and second weeks, respectively. These results indicate that cannibalism in dorada can be mitigated efficiently through appropriate rearing procedures, and open promising perspectives for the intensive culture of this fast-growing tropical species. [source] Shoaling behaviour of the two-spotted gobyJOURNAL OF FISH BIOLOGY, Issue 6 2000P. A. Svensson Naturally formed shoals of adult Gobiusculus flavescens in a Swedish fjord ranged in size from a few individuals to several hundred fish and were sorted by body size. Shoal composition was highly dynamic and any particular group was unlikely to remain together for more than a few hours. Shoaling tendency of juveniles in laboratory experiments was high, and consistent preferences were demonstrated for numerically larger shoals. Large test fish preferred to associate with shoals composed of large, over shoals composed of small fish, whereas small test fish associated with both size classes equally. The ecological importance of shoaling in small shallow water fish is discussed, and possible mechanisms for the observed patterns are proposed. [source] Kisspeptin and the Preovulatory Gonadotrophin-Releasing Hormone/Luteinising Hormone Surge in the Ewe: Basic Aspects and Potential Applications in the Control of OvulationJOURNAL OF NEUROENDOCRINOLOGY, Issue 7 2010A. Caraty The identification of the neural mechanisms controlling ovulation in mammals has long been a ,holy grail' over recent decades, although the recent discovery of the kisspeptin systems has totally changed our views on this subject. Kisspeptin cells are the major link between gonadal steroids and gonadotrophin-releasing hormone (GnRH) neurones. In the female rodent, kisspeptin cells of the preoptic area are involved in the positive-feedback action of oestrogen on GnRH secretion, although the picture appears more complicated in the ewe. As in rodents, activation of preoptic kisspeptin neurones accompanies the GnRH surge in the ewe but an active role for arcuate kisspeptin neurones has also been proposed. Experimentally, kisspeptin is able to restore reproductive function when the hypothalamic-hypophyseal ovarian axis is quiescent. For example, i.v. infusion of a low dose of peptide in anoestrous ewes induces an immediate and sustained release of gonadotrophin, which subsides and then provokes a luteinising hormone (LH) surge a few hours later. This pharmacological intervention induces the same hormonal changes normally observed during the follicular phase of the oestrous cycle, including the secretion of oestrogen and its negative- and positive-feedback actions on the secretion of LH and follicle-stimulating hormone. Accordingly, a high percentage of kisspeptin-infused animals ovulated. Although the multiple facets of how the kisspeptin systems modulate GnRH secretion are not totally understood, the demonstration that exogenous kisspeptin administration can induce ovulation in anovulatory animals paves the way for future therapeutic applications aiming to control reproduction. [source] Neuroplastic Changes in the Brain: A Case of Two Successive Adaptive Changes Within the Motor CortexJOURNAL OF NEUROIMAGING, Issue 3 2010Eytan Raz MD ABSTRACT We describe a case of neuroplasticity associated with both arteriovenous malformation (AVM) and stroke, which occurred in two successive events in the same patient. Functional magnetic resonance imaging (fMRI) during right-hand movement in a young man with a left rolandic AVM detected activation of a region corresponding to the left premotor cortex. The AVM was embolized. A few hours after the last embolization session, the patient sustained an ischemic complication in the left subcortical white matter. A second fMRI detected a lower degree of left premotor cortex activation and strong activation of the contralesional right primary motor cortex and bilateral supplementary motor areas. One month later, in association with clinical recovery, the fMRI activation returned to that observed in the first fMRI, ie, selective activation of the ipsilesional left premotor cortex. This is, to our knowledge, the first description of two distinct functional cortical changes determined by an AVM and a stroke within the motor network. [source] Cefazolin embedded biodegradable polypeptide nanofilms promising for infection prevention: A preliminary study on cell responsesJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 8 2010Hongshuai Li Abstract Implant-associated infection is a serious complication in orthopedic surgery, and endowing implant surfaces with antibacterial properties could be one of the most promising approaches for preventing such infection. In this study, we developed cefazolin loaded biodegradable polypeptide multilayer nanofilms on orthopedic implants. We found that the amount of cefazolin released could be tuned. A high local concentration of cefazolin was achieved within the first a few hours and therefore may inhibit bacterial colonization in the critical postimplantation period. The developed cefazolin loaded nanofilms showed their in vitro efficacy against Staphylococcus aureus; the more antibiotics loaded, the longer the nanocoated implant had antibacterial properties. More interestingly, antibiotic-loaded polypeptide multilayer nanofilms also improved osteoblast bioactivity including cell viability and proliferation. These findings suggested that biodegradable polypeptide multilayer nanofilms as antibiotic carriers at the implant/tissue interface are compatible with human cells such as osteoblasts and bactericidal to bacteria such as S. aureus. These characteristics could be promising for preventing implant-associated infection and potentially improving bone healing. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:992,999, 2010 [source] | ||||||||||||||||||||||||||||