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PC
Kinds of PC Terms modified by PC Selected AbstractsMolecular and serological characterization of hepatitis B virus in deferred Ghanaian blood donors with and without elevated alanine aminotransferaseJOURNAL OF VIRAL HEPATITIS, Issue 11 2006D. Candotti Summary., Candidate blood donors in Ghana are frequent carriers of hepatitis B virus (HBV). A comparative study of 117 donor samples including 46 with alanine aminotransferase (ALT) , 60 IU/L and 71 with ,40 IU/L level was undertaken. S and the basic core promoter-precore regions (BCP/PC) sequencing was used to identify genotypes and variants relevant to HBV natural history, respectively. Age, viral load, HBe status were correlated with molecular data. HBV genotype E (87%) was dominant with little genotypes A (10%) and D (3%). Comparing individuals with or without liver disease, an association between liver disease and older age (P = 0.004) and higher viral load (P = 0.002) whether as a whole population or only genotype E was found. Compared with a commercial assay, BCP/PC sequencing had lower sensitivity to detect mixtures of wild-type and variant viruses but detected BCP deletions. BCP 1762/1764 variants were positively correlated with older age (P < 0.0001) and elevated ALT levels (P = 0.01). PC 1896 stop codon was marginally correlated with viral load (P = 0.09). HBV genotype E infection natural history appears different from genotypes B and C prevalent in Asia. Donors with liver disease being older, with higher viral load and higher BCP variant proportion may be at higher risk of cirrhosis and hepatocellular carcinoma [source] Analysis of a radiographic technique for measurement of equine metacarpal bone shapeEQUINE VETERINARY JOURNAL, Issue S33 2001L. J. WALTER Summary Accuracy and limitations of a radiographic technique were established for measurement of metacarpal bone shape in horses. A radiographic index (RI) has been used to measure changes in third metacarpal (Mc3) bone shape in response to training in young racehorses. The aim of these experiments was to determine the effects of positioning of the radiographic equipment on RI measurements from lateromedial radiographs of a left ex vivo metacarpus. Repeatability of the RI measurement in left lateromedial and right mediolateral view Mc3s were evaluated. The width of the dorsal cortex (DC), palmar cortex (PC) and medulla (M) were measured at a position 25 mm distal to the nutrient foramen and the RI calculated where RI = [(DC+PC)/M] x [DC/PC]. The reference RI values were obtained from 12 standard lateromedial radiographs. Factors analysed included the optimum focus-object distance, the angle at which the x-ray machine was positioned, the distance of the cassette from the limb, and the horizontal angle and vertical tilt of the cassette. The RI values included within the confidence interval (mean ° 1.96 x s.d.) were considered sufficiently accurate. The optimum focus-object distance was 1 m. Accurate measurements were obtained when the cassette was held as close to the limb as possible with the horizontal angle not exceeding 5°. The x-ray machine needed to be orientated within 6° of the lateromedial plane. These findings suggest that the radiographic index can be used to measure Mc3 bone shape, providing there is accurate alignment of the x-ray machine, cassette, and limb, with respect to one another. [source] Transplantation of galectin-1-expressing human neural stem cells into the injured spinal cord of adult common marmosetsJOURNAL OF NEUROSCIENCE RESEARCH, Issue 7 2010Junichi Yamane Abstract Delayed transplantation of neural stem/progenitor cells (NS/PCs) into the injured spinal cord can promote functional recovery in adult rats and monkeys. To enhance the functional recovery after NS/PC transplantation, we focused on galectin-1, a carbohydrate-binding protein with pleiotropic roles in cell growth, differentiation, apoptosis, and neurite outgrowth. Here, to determine the combined therapeutic effect of NS/PC transplantation and galectin-1 on spinal cord injury (SCI), human NS/PCs were transfected by lentivirus with galectin-1 and green fluorescent protein (GFP), (Gal-NS/PCs) or GFP alone (GFP-NS/PCs), expanded in vitro, and then transplanted into the spinal cord of adult common marmosets, 9 days after contusive cervical SCI. The animals' motor function was evaluated by their spontaneous motor activity, bar grip power, and performance on a treadmill test. Histological analyses revealed that the grafted human NS/PCs survived and differentiated into neurons, astrocytes, and oligodendrocytes. There were significant differences in the myelinated area, corticospinal fibers, and serotonergic fibers among the Gal-NS/PC, GFP-NS/PC, vehicle-control, and sham-operated groups. The Gal-NS/PC-grafted animals showed a better performance on all the behavioral tests compared with the other groups. These findings suggest that Gal-NS/PCs have better therapeutic potential than NS/PCs for SCI in nonhuman primates and that human Gal-NS/PC transplantation might be a feasible treatment for human SCI. © 2010 Wiley-Liss, Inc. [source] Solid polymer electrolytes I, preparation, characterization, and ionic conductivity of gelled polymer electrolytes based on novel crosslinked siloxane/poly(ethylene glycol) polymersJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 9 2004Ping-Lin Kuo Abstract A series of crosslinked siloxane/poly(ethylene glycol) (Si,PEG) copolymers were synthesized from the reactive methoxy-functional silicone resin (Si resin) and PEGs with different molecular weights via two kinds of crosslinking reactions during an in situ curing stage. One of the crosslinking reactions is the self-condensation between two methoxy groups in the Si resin, and another one is an alkoxy-exchange reaction between the methoxy group in the Si resin and the OH group in PEG. The synthesized crosslinked copolymers were characterized by Fourier transform infrared spectroscopy, DSC, and 13C NMR. The crosslinked copolymers were stable in a moisture-free environment, but the SiOC linkages were hydrolyzed in humid conditions. The gel-like solid polymer electrolytes (SPEs) were prepared by impregnating these crosslinked Si,PEG copolymers in a propylene carbonate (LiClO4/PC) solution. The highest conductivity reached 2.4 × 10,4 S cm,1 at 25 °C and increased to 8.7 × 10,4 S cm,1 at 85 °C. The conductivities of these gel-type SPEs were affected by the content of LiClO4/PC, the molecular weights of PEGs, and the weight fraction of the Si resin. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2051,2059, 2004 [source] Synthesis of networked polymers with lithium counter cations from a difunctional epoxide containing poly(ethylene glycol) and an epoxide monomer carrying a lithium sulfonate salt moietyJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 14 2010Kozo Matsumoto Abstract Poly(ethylene glycol)-based networked polymers that had lithium sulfonate salt structures on the network were prepared by heating a mixture of poly(ethylene glycol) diglycidyl ether (PEGGE), poly(ethylene glycol) bis(3-aminopropyl) terminated (PEGBA), and an ionic epoxy monomer, lithium 3-glycidyloxypropanesulfonate (LiGPS). Flexible self-standing networked polymer films showed high thermal stability, low crystallinity, low glass transition temperature, and good mechanical strength. The materials were ion conductive at room temperature even under a dry condition, although the ionic conductivity was rather low (10,6 to 10,5 S/m). The ionic conductivity increased with the increase in temperature to above 1 × 10,4 S/m at 90 °C. The film samples became swollen by immersing in propylene carbonate (PC) or PC solution of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). The samples swollen in PC showed higher ionic conductivity (ca.1 × 10,3 S/m at room temperature), and the samples swollen in LiTFSI/PC showed much higher ionic conductivity (nearly 1 S/m at room temperature). © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3113,3118, 2010 [source] Shear-stimulated formation of multi-wall carbon nanotube networks in polymer meltsPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 11-12 2009T. Skipa Abstract We report on shear-induced nanotube network formation in multi-wall nanotubes/polycarbonate (MWNT/PC) composite melts which was directly monitored by the time-resolved DC-conductivity measurements during steady shear. A small steady shear applied for 1,h to a non-conductive composite with initially well-dispersed nanotubes was found to induce the insulator-to-conductor transition resulting in a conductivity increase by about six orders of magnitude. Similar composite melt annealed without steady shear demonstrates much slower process of the network formation what can be attributed to an agglomeration of attractively interacting nanotubes in polymer melts. The rheologic properties were also measured for shear-stimulated agglomeration. Unexpected difference between the electrical and mechanical networks in MWNT/PC composites was found. For the modeling of the network formation a shear-dependent kinetic equation for the nanotube agglomeration was coupled with empirical formula for insulator-to-conductor transition. Electric DC-conductivity and shear modulus (G, and G,) of MWNT/PC melt (230,°C) measured simultaneously during shear-stimulated network formation. [source] GPU-based interactive visualization framework for ultrasound datasetsCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 1 2009Sukhyun Lim Abstract Ultrasound imaging is widely used in medical areas. By transmitting ultrasound signals into the human body, their echoed signals can be rendered to represent the shape of internal organs. Although its image quality is inferior to that of CT or MR, ultrasound is widely used for its speed and reasonable cost. Volume rendering techniques provide methods for rendering the 3D volume dataset intuitively. We present a visualization framework for ultrasound datasets that uses programmable graphics hardware. For this, we convert ultrasound coordinates into Cartesian form. In ultrasound datasets, however, since physical storage and representation space is different, we apply different sampling intervals adaptively for each ray. In addition, we exploit multiple filtered datasets in order to reduce noise. By our method, we can determine the adequate filter size without considering the filter size. As a result, our approach enables interactive volume rendering for ultrasound datasets, using a consumer-level PC. Copyright © 2009 John Wiley & Sons, Ltd. [source] Multi-resolution collision handling for cloth-like simulationsCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3-4 2005Nitin Jain Abstract We present a novel multi-resolution algorithm for simulation of complex cloth-like deforming meshes. Our algorithm precomputes a multi-resolution hierarchy by using a combination of ,chromatic decomposition'1 and polygonal simplification of the underlying mesh. At runtime we selectively refine or coarsen the mesh based on the collision proximity of the mesh primitives with non-adjacent primitives. Our algorithm handles all kind of contacts, including self collisions among mesh primitives. The multi-resolution hierarchy is used to compute simplification of contact manifolds and to accelerate collision detection and response computations. We have implemented our algorithm on a high-end PC and applied it to complex simulations with tens of thousands of polygons. In practice, our algorithm is able to achieve interactive performance, while maintaining good visual fidelity. Copyright © 2005 John Wiley & Sons, Ltd. [source] Audio processors as a learning tool for basic acousticsCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 4 2009Arcadi Pejuan Abstract Audio processors like Audacity provide a "hear-and-see" learning tool for basic acoustics, combining sound and image. Activities designed as laboratory experiments with PC (even at home!) have been already successfully implemented, for example, about the dependence of timbre and acoustic spectrum, of pitch and frequency, and of loudness and amplitude. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 17: 379,388, 2009; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20207 [source] An educational tool for controlling of SRMCOMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 4 2008Tuncay Yigit Abstract This article introduces an educational tool for a switched reluctance motor (SRM) drive system. It is prepared for undergraduate and graduate level students. Classical PI and Genetic PI controllers are used in SRM drive system. The Genetic PI controller was applied to the speed loop, replacing the classical PI controller. The tool software was implemented using C++ Builder on a PC. It has flexible structure and graphical interface. The students can be easily establishing a thorough understanding of both classical PI and genetic PI controller for a SRM drive system. The education tool allowed the student to interact with the SRM drive system and it is using controllers. Then it is responses on a dynamic and instantaneous basis under different operating conditions. © 2008 Wiley Periodicals, Inc. Comput Appl Eng Educ 16: 268,279, 2008; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae20148 [source] Fast and Scalable CPU/GPU Collision Detection for Rigid and Deformable SurfacesCOMPUTER GRAPHICS FORUM, Issue 5 2010Simon Pabst Abstract We present a new hybrid CPU/GPU collision detection technique for rigid and deformable objects based on spatial subdivision. Our approach efficiently exploits the massive computational capabilities of modern CPUs and GPUs commonly found in off-the-shelf computer systems. The algorithm is specifically tailored to be highly scalable on both the CPU and the GPU sides. We can compute discrete and continuous external and self-collisions of non-penetrating rigid and deformable objects consisting of many tens of thousands of triangles in a few milliseconds on a modern PC. Our approach is orders of magnitude faster than earlier CPU-based approaches and up to twice as fast as the most recent GPU-based techniques. [source] Hierarchical Convex Approximation of 3D Shapes for Fast Region SelectionCOMPUTER GRAPHICS FORUM, Issue 5 2008Marco Attene Abstract Given a 3D solid model S represented by a tetrahedral mesh, we describe a novel algorithm to compute a hierarchy of convex polyhedra that tightly enclose S. The hierarchy can be browsed at interactive speed on a modern PC and it is useful for implementing an intuitive feature selection paradigm for 3D editing environments. Convex parts often coincide with perceptually relevant shape components and, for their identification, existing methods rely on the boundary surface only. In contrast, we show that the notion of part concavity can be expressed and implemented more intuitively and efficiently by exploiting a tetrahedrization of the shape volume. The method proposed is completely automatic, and generates a tree of convex polyhedra in which the root is the convex hull of the whole shape, and the leaves are the tetrahedra of the input mesh. The algorithm proceeds bottom-up by hierarchically clustering tetrahedra into nearly convex aggregations, and the whole process is significantly fast. We prove that, in the average case, for a mesh of n tetrahedra O(n log2 n) operations are sufficient to compute the whole tree. [source] Fast Volume Rendering and Data Classification Using Multiresolution in Min-Max OctreesCOMPUTER GRAPHICS FORUM, Issue 3 2000Feng Dong Large-sized volume datasets have recently become commonplace and users are now demanding that volume-rendering techniques to visualise such data provide acceptable results on relatively modest computing platforms. The widespread use of the Internet for the transmission and/or rendering of volume data is also exerting increasing demands on software providers. Multiresolution can address these issues in an elegant way. One of the fastest volume-rendering alrogithms is that proposed by Lacroute & Levoy 1 , which is based on shear-warp factorisation and min-max octrees (MMOs). Unfortunately, since an MMO captures only a single resolution of a volume dataset, this method is unsuitable for rendering datasets in a multiresolution form. This paper adapts the above algorithm to multiresolution volume rendering to enable near-real-time interaction to take place on a standard PC. It also permits the user to modify classification functions and/or resolution during rendering with no significant loss of rendering speed. A newly-developed data structure based on the MMO is employed, the multiresolution min-max octree, M 3 O, which captures the spatial coherence for datasets at all resolutions. Speed is enhanced by the use of multiresolution opacity transfer functions for rapidly determining and discarding transparent dataset regions. Some experimental results on sample volume datasets are presented. [source] Fast Reciprocating Probe Assembly for the KSTARCONTRIBUTIONS TO PLASMA PHYSICS, Issue 5-6 2006J. G. Bak Abstract A fast reciprocating probe assembly (FRPA) that can scan a distance of up to 32.5 cm with a maximum speed of 1.7 m/s was fabricated to obtain the spatial profile of basic plasma parameters in the edge region of the KSTAR plasma during a plasma discharge of 20 s. The probe driving mechanism consists of two parts; first a slow movement driven by a servo motor system and then a fast reciprocating movement actuated by a pneumatic system. A performance test of the drive system, which is remotely controlled by a PC, was carried out. The prototype of the probe head for the KSTAR FRPA was fabricated as a modular type for easy replacement. It was installed in the fast injection probe assembly (FIPA) in the Hanbit magnetic mirror device, and a radial plasma parameter profile measurement was carried out. The performance test results of the drive system and the profile measurements using the probe head are presented. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Structural, electrical and optical properties of Ge implanted GaSe single crystals grown by Bridgman techniqueCRYSTAL RESEARCH AND TECHNOLOGY, Issue 12 2006H. Karaa Abstract Structural, optical and electrical properties of Ge implanted GaSe single crystal have been studied by means of X-Ray Diffraction (XRD), temperature dependent conductivity and photoconductivity (PC) measurements for different annealing temperatures. It was observed that upon implanting GaSe with Ge and applying annealing process, the resistivity is reduced from 2.1 × 109 to 6.5 × 105 ,-cm. From the temperature dependent conductivities, the activation energies have been found to be 4, 34, and 314 meV for as-grown, 36 and 472 meV for as-implanted and 39 and 647 meV for implanted and annealed GaSe single crystals at 500°C. Calculated activation energies from the conductivity measurements indicated that the transport mechanisms are dominated by thermal excitation at different temperature intervals in the implanted and unimplanted samples. By measuring photoconductivity (PC) measurement as a function of temperature and illumination intensity, the relation between photocurrent (IPC) and illumination intensity (,) was studied and it was observed that the relation obeys the power law, IPC ,,n with n between 1 and 2, which is indication of behaving as a supralinear character and existing continuous distribution of localized states in the band gap. As a result of transmission measurements, it was observed that there is almost no considerable change in optical band gap of samples with increasing annealing temperatures for as-grown GaSe; however, a slight shift of optical band gap toward higher energies for Ge-implanted sample was observed with increasing annealing temperatures. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Multiparameter immunophenotyping by flow cytometry in multiple myeloma: The diagnostic utility of defining ranges of normal antigenic expression in comparison to histology,CYTOMETRY, Issue 4 2010Elisa Cannizzo Abstract Background: Numerous studies have reported on the immunophenotype of plasma cells (PCs) in monoclonal gammopathy of undetermined significance (MGUS) and in plasma cell myeloma (PCM), but very few have examined the immunophenotype of normal PCs. In this study, an objective definition of normal range of expression for each antigen was found on normal control PCs. Using these new ranges of normal expression (new method) is different from using a static 20% of PCs cut-off for all antigens as described in the literature (traditional method). These newly calculated normal ranges for each antigen were applied to our data, and compared to histologic and immunohistochemical findings. Methods: Bone marrow samples from 46 patients with PC neoplasms and 15 normal controls were studied. A minimum of 100 PC were analyzed for each patient and control sample. An 8-color staining method was applied to study the immunophenotype of PCs, using a BD FACSCanto II. Results: By the new ranges of normality calculated in this study it was determined that different antigens have different level of expression on polyclonal PCs. CD19 correlated with histology by both the traditional and new methods, but had superior correlation by the new method. Conclusions: This report is the first 8-color immunophenotypic study of PCM in which a "range of normal expression" for each antigen is defined. This is a critical step to help distinguish between a normal and neoplastic PC immunophenotype and discern which antigens are of diagnostic importance. © 2010 Clinical Cytometry Society [source] Utility of flow cytometry immunophenotyping in multiple myeloma and other clonal plasma cell-related disorders,CYTOMETRY, Issue 4 2010Bruno Paiva Abstract In recent years, multiparameter flow cytometry (MFC) immunophenotyping has become mandatory in the clinical management of hematological malignancies, both for diagnostic and monitoring purposes. Multiple myeloma (MM) and other clonal plasma cell-related (PC) disorders should be no exception to this paradigm, but incorporation of immunophenotypic studies in the management of patients with PC disorders is still far from being routinely established in many diagnostic flow cytometry laboratories. For clonal PC disorders, MFC is of clear and established clinical relevance in: (1) the differential diagnosis between MM and other PC-related disorders; (2) the identification of high-risk MGUS and smoldering MM; (3) minimal residual disease investigation after therapy; additionally it may also be useful for (4) the definition of prognosis-associated antigenic profiles; and (5) the identification of new therapeutic targets. In this article, we review the clinical value of MFC in the study of PC disorders, with specific emphasis in those areas where consensus exists on the need to incorporate MFC into routine evaluation of MM and other clonal PC-related disorders. © 2010 Clinical Cytometry Society [source] Presurgical Curettage Appropriately Reduces the Number of Mohs Stages by Better Delineating the Subclinical Extensions of Tumor MarginsDERMATOLOGIC SURGERY, Issue 9 2005Vinh Q. Chung MD Background. Whether presurgical curettage (PC), light curettage performed before Mohs surgery to delineate tumor margin, is appropriate or causes unnecessary removal of normal tissue has not been well established. Objective. We aim to determine histologically whether PC appropriately increases the size of the stage I specimen or causes unnecessary removal of healthy tissue. Methods. Before a surgical margin guided by PC was taken, a hypothetical margin determined by visual and tactile assessment alone (no curettage [NC]) was marked outside the clinically defined tumor. Histologic analysis at the NC and the PC margins revealed whether the increase in the stage I specimen as a result of PC was appropriate. Results. PC appropriately increased the stage I specimen in 21 cases and unnecessarily removed normal tissue in only 1 case. The estimation of tumor margins with PC was 15 times more accurate than with NC (p value = .0012). Conclusion. For basal cell and squamous cell carcinomas at least 4 mm in diameter, light curettage performed prior to Mohs surgery could better delineate subclinical extensions of the tumor margin and appropriately increase the size of the stage I specimen. [source] Polarized expression of integrin ,1 in diencephalic roof plate during chick development, a possible receptor for SCO-spondinDEVELOPMENTAL DYNAMICS, Issue 10 2009Teresa Caprile Abstract The roof plate of the caudal diencephalon is formed by the posterior commissure (PC) and the underlying secretory ependyma, the subcommissural organ (SCO). The SCO is composed by radial glial cells bearing processes that cross the PC and attach to the meningeal basement membrane. Since early development, the SCO synthesizes SCO-spondin, a glycoprotein that shares similarities to axonal guidance proteins. In vitro, SCO-spondin promotes neuritic outgrowth through a mechanism mediated by integrin ,1. However, the secretion of SCO-spondin toward the extracellular matrix that surrounds the PC axons and the expression of integrins throughout PC development have not been addressed. Here we provide immunohistochemical evidence to suggest that during chick development SCO cells secrete SCO-spondin through their basal domain, where it is deposited into the extracellular matrix in close contact with axons of the PC that express integrin ,1. Our results suggest that SCO-spondin has a role in the development of the PC through its interaction with integrin ,1. Developmental Dynamics 238:2494,2504, 2009. © 2009 Wiley-Liss, Inc. [source] Differential expression of TrkB isoforms switches climbing fiber-Purkinje cell synaptogenesis to selective synapse eliminationDEVELOPMENTAL NEUROBIOLOGY, Issue 10 2009Rachel M. Sherrard Abstract Correct neural function depends on precisely organized connectivity, which is refined from broader projections through synaptic/collateral elimination. In the rat, olivocerebellar topography is refined by regression of multiple climbing fiber (CF) innervation of Purkinje cells (PC) during the first two postnatal weeks. The molecules that initiate this regression are not fully understood. We assessed the role of cerebellar neurotrophins by examining tropomycin receptor kinase (Trk) receptor expression in the inferior olive and cerebellum between postnatal days (P)3-7, when CF-PC innervation changes from synapse formation to selective synapse elimination, and in a denervation-reinnervation model when synaptogenesis is delayed. Trks A, B, and C are expressed in olivary neurons; although TrkA was not transported to the cerebellum and TrkC was unchanged during innervation and reinnervation, suggesting that neither receptor is involved in CF-PC synaptogenesis. In contrast, both total and truncated TrkB (TrkB.T) increased in the olive and cerebellum from P4, whereas full-length and activated phosphorylated TrkB (phospho-TrkB) decreased from P4-5. This reveals less TrkB signaling at the onset of CF regression. This expression pattern was reproduced during CF-PC reinnervation: in the denervated hemicerebellum phospho-TrkB decreased as CF terminals degenerated, then increased in parallel with the delayed neosynaptogenesis as new CFs reinnervated the denervated hemicerebellum. In the absence of this signaling, CF reinnervation did not develop. Our data reveal that olivocerebellar TrkB activity parallels CF-PC synaptic formation and stabilization and is required for neosynaptogenesis. Furthermore, TrkB.T expression rises to reduce TrkB signaling and permit synapse elimination. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 2009 [source] Predictors of glycaemic control in indigent patients presenting with diabetic ketoacidosisDIABETES OBESITY & METABOLISM, Issue 3 2005M. Maldonado Aim:, To derive predictors of good glycaemic control in patients presenting with diabetic ketoacidosis (DKA) followed prospectively in a specialized clinic. Methods:, One hundred and sixty-one adult patients were admitted during a 31-month period and followed for at least 12 months. After 1 year, the patients were classified into three groups: good control (GC) (HbA1c , 7%), intermediate control (IC) (HbA1c 7,9%) and poor control (PC) (HbA1c > 9%). Characteristics of patients in the three groups were compared both at baseline and during follow-up. Results:, At 12 months, 36% of the patients were classified as GC, 27% as IC and 37% as PC. GC patients had higher fasting serum C-peptide levels 0.7 ± 0.54 compared to 0.38 ± 0.29 and 0.16 ± 0.21 nmol/l, respectively, for the IC and PC patients (p < 0.0001). A higher proportion GC patient had a C-peptide level greater than 0.33 nmol/l than that for IC and PC patients (86, 61 and 19%, respectively; p < 0.0001). Exogenous insulin was safely discontinued in 50, 30 and 3% of patients, respectively, in the GC, IC and PC groups (p < 0.0001). Compliance with life-style interventions was higher in the GC than that in IC and PC patients (87, 41 and 5%, respectively; p < 0.0001). In the logistic regression analysis, predictors of good glycaemic control were having baseline fasting serum C-peptide value ,0.33 mmol/l, OR: 3.01 (95% CI 1.07,8.55, p = 0.03) and compliance with life-style interventions OR 12.66 (95% CI 3.73,51.57, p = 0.0001). Conclusion:, Among adult patients with DKA, significant predictors of good glycaemic control are preserved ,-cell function and compliance with life-style modifications. [source] RangeModel: tools for exploring and assessing geometric constraints on species richness (the mid-domain effect) along transectsECOGRAPHY, Issue 1 2008Robert K. ColwellArticle first published online: 4 FEB 200 RangeModel is a computer application that offers animated demonstrations of the mechanism behind the mid-domain effect. The program also provides analytical tools for the assessment of geometric constraints in empirical datasets for one-dimensional domains (transects). The mid-domain effect (MDE) is the increasing overlap of species ranges towards the center of a shared, bounded domain due to geometric boundary constraints in relation to the distribution of range sizes, producing a peak or plateau of species richness towards the center of the domain. Domains may be spatial, temporal, or functional. RangeModel is a stand-alone, graphical-interface, freeware application for PC and Mac OS platforms. [source] Relative influences of catchment- and reach-scale abiotic factors on freshwater fish communities in rivers of northeastern MesoamericaECOLOGY OF FRESHWATER FISH, Issue 3 2010P. C. Esselman Esselman PC, Allan JD. Relative influences of catchment- and reach-scale abiotic factors on freshwater fish communities in rivers of northeastern Mesoamerica. Ecology of Freshwater Fish 2010: 19: 439,454. © 2010 John Wiley & Sons A/S Abstract,,, While the abiotic factors important to freshwater fish assemblages at a reach scale are well understood, studies of larger scale constraints have yielded variable conclusions, spurring a need for further studies in new biogeographic contexts. This study investigated the importance of catchment- and reach-scale abiotic factors to variation in freshwater fish assemblages in rivers of northeastern Mesoamerica. Abiotic variables and fish data from 72 sampling sites on main stem rivers of Belize were used with partial constrained ordination to determine the proportion of spatially structured and unstructured variation in fish presence and absence, relative abundance, and community metrics explained by catchment- and reach-scale environmental factors. Results showed that, combined, catchment and reach variables explained a large portion of the total variation in the fish assemblage data (54,75%), and that catchment environment explained a greater portion of variation (42,63%) than reach environment (34,50%). Variables representing landscape position (local elevation, watershed area) and their reach-level correlates (channel width, depth variation, and substrate) correlated strongly to the fish assemblage data. Our results suggest that landscape-scale factors have a stronger relative influence on assemblages than environmental conditions at the reach scale within our study area. These results contrast with past findings that showed greater local scale influence in landscapes with low anthropogenic disturbance levels. Our findings suggest that biodiversity conservation efforts should consider assemblage variation across a longitudinal gradient, and that a multi-catchment region is a biologically relevant scale for fish conservation planning and coordination in northeastern Mesoamerica. [source] Electrochemical Biosensor for the Detection of Interaction Between Arsenic Trioxide and DNA Based on Guanine SignalELECTROANALYSIS, Issue 7 2003Mehmet Ozsoz Abstract The interaction of arsenic trioxide (As2O3) with calf thymus double-stranded DNA (dsDNA), calf thymus single-stranded DNA (ssDNA) and also 17-mer short oligonucleotide (Probe,A) was studied electrochemically by using differential pulse voltammetry (DPV) with carbon paste electrode (CPE) at the surface and also in solution. Potentiometric stripping analysis (PSA) was employed to monitor the interaction of As2O3 with dsDNA in solution phase by using a renewable pencil graphite electrode (PGE). The changes in the experimental parameters such as the concentration of As2O3, and the accumulation time of As2O3 were studied by using DPV; in addition, the reproducibility data for the interaction between DNA and As2O3 was determined by using both electrochemical techniques. After the interaction of As2O3 with dsDNA, the DPV signal of guanine was found to be decreasing when the accumulation time and the concentration of As2O3 were increased. Similar DPV results were also found with ssDNA and oligonucleotide. PSA results observed at a low DNA concentration such as 1,ppm and a different working electrode such as PGE showed that there could be damage to guanine bases. The partition coefficients of As2O3 after interaction with dsDNA and ssDNA in solution by using CPE were calculated. Similarly, the partition coefficients (PC) of As2O3 after interaction with dsDNA in solution was also calculated by PSA at PGE. The features of this proposed method for the detection of DNA damage by As2O3 are discussed and compared with those methods previously reported for the other type of DNA targeted agents in the literature. [source] Waste management modeling with PC-based model , EASEWASTEENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY, Issue 1 2008Gurbakhash S. Bhander Abstract As life-cycle-thinking becomes more integrated into waste management, quantitative tools are needed for assessing waste management systems and technologies. This article presents a decision support model to deal with integrated solid waste management planning problems at a regional or national level. The model is called EASEWASTE (environmental assessment of solid waste systems and technologies). The model consists of a number of modules (submodels), each describing a process in a real waste management system, and these modules may combine to represent a complete waste management system in a scenario. EASEWASTE generates data on emissions (inventory), which are translated and aggregated into different environmental impact categories, e.g. the global warming, acidification, and toxicity. To facilitate a "first level" screening evaluation, default values for process parameters have been provided, wherever possible. The EASEWASTE model for life-cycle-assessment of waste management is described and applied to a case study for illustrative purposes. The case study involving hypothetical but realistic data demonstrates the functionality, usability, and flexibilities of the model. The design and implementation of the software successfully address the substantial challenges in integrating process modeling, life-cycle inventory (LCI), and impact assessment (LCIA) modeling, and optimization into an interactive decision support platform. © 2008 American Institute of Chemical Engineers Environ Prog, 2008 [source] ,9 -Tetrahydrocannabivarin suppresses in vitro epileptiform and in vivo seizure activity in adult ratsEPILEPSIA, Issue 8 2010Andrew J. Hill Summary Purpose:, We assessed the anticonvulsant potential of the phytocannabinoid ,9 -tetrahydrocannabivarin (,9 -THCV) by investigating its effects in an in vitro piriform cortex (PC) brain slice model of epileptiform activity, on cannabinoid CB1 receptor radioligand-binding assays and in a generalized seizure model in rats. Methods:, ,9 -THCV was applied before (10 ,m,9 -THCV) or during (10,50 ,m,9 -THCV) epileptiform activity induced by Mg2+ -free extracellular media in adult rat PC slices and measured using multielectrode array (MEA) extracellular electrophysiologic techniques. The actions of ,9 -THCV on CB1 receptors were examined using [3H]SR141716A competition binding and [35S]GTP,S assays in rat cortical membranes. Effects of ,9 -THCV (0.025,2.5 mg/kg) on pentylenetetrazole (PTZ),induced seizures in adult rats were also assessed. Results:, After induction of stable spontaneous epileptiform activity, acute ,9 -THCV application (,20 ,m) significantly reduced burst complex incidence and the amplitude and frequency of paroxysmal depolarizing shifts (PDSs). Furthermore, slices pretreated with 10 ,m,9 -THCV prior to induction of epileptiform activity exhibited significantly reduced burst complex incidence and PDS peak amplitude. In radioligand-binding experiments, ,9 -THCV acted as a CB1 receptor ligand, displacing 0.5 nm [3H]SR141716A with a Ki,290 nm, but exerted no agonist stimulation of [35S]GTP,S binding. In PTZ-induced seizures in vivo, 0.25 mg/kg ,9 -THCV significantly reduced seizure incidence. Discussion:, These data demonstrate that ,9 -THCV exerts antiepileptiform and anticonvulsant properties, actions that are consistent with a CB1 receptor,mediated mechanism and suggest possible therapeutic application in the treatment of pathophysiologic hyperexcitability states. [source] Propagation Dynamics of Epileptiform Activity Acutely Induced by Bicuculline in the Hippocampal,Parahippocampal Region of the Isolated Guinea Pig BrainEPILEPSIA, Issue 12 2005Laura Uva Summary:,Purpose: Aim of the study is to investigate the involvement of parahippocampal subregions in the generation and in the propagation of focal epileptiform discharges in an acute model of seizure generation in the temporal lobe induced by arterial application of bicuculline in the in vitro isolated guinea pig brain preparation. Methods: Electrophysiological recordings were simultaneously performed with single electrodes and multichannel silicon probes in the entorhinal, perirhinal, and piriform cortices and in the area CA1 of the hippocampus of the in vitro isolated guinea pig brain. Interictal and ictal epileptiform discharges restricted to the temporal region were induced by a brief (3,5 min) arterial perfusion of the GABAA receptor antagonist, bicuculline methiodide (50 ,M). Current source density analysis of laminar field profiles performed with the silicon probes was carried out at different sites to establish network interactions responsible for the generation of epileptiform potentials. Nonlinear regression analysis was conducted on extracellular recordings during ictal onset in order to quantify the degree of interaction between fast activities generated at different sites, as well as time delays. Results: Experiments were performed in 31 isolated guinea pig brains. Bicuculline-induced interictal and ictal epileptiform activities that showed variability of spatial propagation and time course in the olfactory,temporal region. The most commonly observed pattern (n = 23) was characterized by the initial appearance of interictal spikes (ISs) in the piriform cortex (PC), which propagated to the lateral entorhinal region. Independent and asynchronous preictal spikes originated in the entorhinal cortex (EC)/hippocampus and progressed into ictal fast discharges (around 25 Hz) restricted to the entorhinal/hippocampal region. The local generation of fast activity was verified and confirmed both by CSD and phase shift analysis performed on laminar profiles. Fast activity was followed by synchronous afterdischarges that propagated to the perirhinal cortex (PRC) (but not to the PC). Within 1,9 min, the ictal discharge ceased and a postictal period of depression occurred, after which periodic ISs in the PC resumed. Unlike preictal ISs, postictal ISs propagated to the PRC. Conclusions: Several studies proposed that reciprocal connections between the entorhinal and the PRC are under a very efficient inhibitory control (1). We report that ISs determined by acute bicuculline treatment in the isolated guinea pig brain progress from the PC to the hippocampus/EC just before ictal onset. Ictal discharges are characterized by a peculiar pattern of fast activity that originates from the entorhinal/hippocampal region and only secondarily propagates to the PRC. Postictal propagation of ISs to the PRC occured exclusively when an ictal discharge was generated in the hippocampal/entorhinal region. The results suggest that reiteration of ictal events may promote changes in propagation pattern of epileptiform discharges that could act as trigger elements in the development of temporal lobe epilepsy. [source] Dynamic pharyngeal collapse in racehorsesEQUINE VETERINARY JOURNAL, Issue S36 2006A. G. BOYLE Summary Reason for performing study: Dynamic pharyngeal collapse (PC) is a condition seen in racehorses that can be career-ending. Objectives: To characterise and grade PC and describe the effects of PC on athletic performance. Methods: Medical records were reviewed for 828 horses, of which 49 (6%) records were identified as horses with a primary diagnosis of PC. Tapes of video-endoscopy of the pharynx during exercise were reviewed. Each video recording was assigned a grade (0,4) reflecting the degree of PC and a classification for severity of upper airway obstruction. Earnings per race prior to diagnosis of PC were compared to earnings per race after diagnosis of PC for all horses, as well as performance index (PI). Available exercising arterial blood gases were reviewed for horses with PC. Results: There were 35 (80%) Thoroughbreds (TB), and 9 (20%) Standardbreds (STD). 32 (73%) had a history of making an upper respiratory noise. 4 (9%) grade 1 PC, 8 (18%) grade 2 PC, 26 (59%) grade 3 PC, and 6 (14%) grade 4 PC. Seven (16%) horses were classified as mild PC, 18 (41%) as low-moderate PC, 14 (32%) as high-moderate PC, and 5 (11%) as severe PC. Of 30 horses 11 had abnormally decreased PaO2 and 8 horses had abnormally elevated PaCO2. A significant decrease was found in earnings per race prediagnosis when compared to post diagnosis earnings per race in horses ?4 years of age (P = 0.003). A significant decrease was also observed for earnings per race prediagnosis when compared to post diagnosis earnings per race in horses with grade 3 PC (P = 0.03) No significant differences were observed in PI before or after diagnosis of PC. Conclusions: There was a trend for PC to be observed in more TB than STD, and more males than females compared to the general hospital population. Horses with PC significant had decreases in arterial oxygenation. Racing records after a diagnosis of PC in all horses ?4 years of age suggesting that older horses have a guarded prognosis for continued success. Potential relevance: This study provides a classification system for dynamic pharyngeal collapse and suggests that older racehorses (?4 years of age) diagnosed with PC and all horses with grade 3 PC have a poor prognosis for return to previous level of performance. [source] Analysis of a radiographic technique for measurement of equine metacarpal bone shapeEQUINE VETERINARY JOURNAL, Issue S33 2001L. J. WALTER Summary Accuracy and limitations of a radiographic technique were established for measurement of metacarpal bone shape in horses. A radiographic index (RI) has been used to measure changes in third metacarpal (Mc3) bone shape in response to training in young racehorses. The aim of these experiments was to determine the effects of positioning of the radiographic equipment on RI measurements from lateromedial radiographs of a left ex vivo metacarpus. Repeatability of the RI measurement in left lateromedial and right mediolateral view Mc3s were evaluated. The width of the dorsal cortex (DC), palmar cortex (PC) and medulla (M) were measured at a position 25 mm distal to the nutrient foramen and the RI calculated where RI = [(DC+PC)/M] x [DC/PC]. The reference RI values were obtained from 12 standard lateromedial radiographs. Factors analysed included the optimum focus-object distance, the angle at which the x-ray machine was positioned, the distance of the cassette from the limb, and the horizontal angle and vertical tilt of the cassette. The RI values included within the confidence interval (mean ° 1.96 x s.d.) were considered sufficiently accurate. The optimum focus-object distance was 1 m. Accurate measurements were obtained when the cassette was held as close to the limb as possible with the horizontal angle not exceeding 5°. The x-ray machine needed to be orientated within 6° of the lateromedial plane. These findings suggest that the radiographic index can be used to measure Mc3 bone shape, providing there is accurate alignment of the x-ray machine, cassette, and limb, with respect to one another. [source] ,-tocopherol improves impaired physiology of rat type II pneumocytes isolated from experimentally injured lungsEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 11 2000B. Müller Background Oxidant stress delivered by nitrogen dioxide (NO2) inhalation impairs the function of extracellular surfactant as well as surfactant phospholipid metabolism in type II pneumocytes. Because protection against oxidant stress is important to normal lung function, the lung contains a variety of antioxidants, including vitamin E. Whether administration of this antioxidant during NO2 inhalation attenuates NO2 -induced alterations in phospholipid metabolism in type II pneumocytes has not been studied. Methods We exposed rats to identical NO2 body doses (720 p.p.m. x h) using continuous, intermittent, or repetitive protocols. During exposure periods, the animals received daily intramuscular injections of vitamin E (25 mg kg,1). We isolated type II pneumocytes from NO2 -exposed rats and evaluated them for cell yield and viability, as well as for synthesis and secretion of phosphatidylcholine (PC) as measures of surfactant metabolism. Results The yield of type II pneumocytes was significantly elevated from animals that had been exposed continuously to NO2 whereas in intermittently and repeatedly exposed rats, cell yield was similar to yield from control animals. Viability of the isolated cells was similar in controls and all NO2 exposure protocols. Vitamin E treatment of the NO2 -exposed rats neither changed cell yield nor cell viability. Phospholipid de novo synthesis, as estimated by choline incorporation into PC, was increased most after continuous NO2 inhalation whereas in the other conditions there was only a slight increase. Vitamin E administration further increased phospholipid synthesis; this difference reached statistical significance only in the case of intermittent NO2 exposure. Secretion of phosphatidylcholine from type II cells was only reduced after continuous NO2 inhalation and administration of the antioxidant reduced the impairment. Conclusion Because vitamin E appears to preserve the ability of type II pneumocytes isolated from NO2 -exposed rats to synthesize and secrete surfactant lipid, we conclude that administration of vitamin E may mitigate NO2 -induced lung injury. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||