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PubMed1986

Evaluation and comparison of cathodic trypsin-like immunoreactivity, pancreatic lipase and pancreatic isoamylase in the diagnosis of acute pancreatitis in 849 consecutive patients with acute abdominal pain.

In 849 patients (417 men, 432 women) consecutively hospitalized with acute abdominal pain we compared the value of serum cathodic trypsin-like immunoreactivity, pancreatic lipase (EC 3.2.1.3) and pancreatic isoamylase (EC 3.2.1.1) as diagnostic tests for acute pancreatitis. The diagnoses of acute pancreatitis (in 49 patients, 5.8%) and other diseases were made without knowledge of these enzyme values. When evaluated by means of receiver operating characteristic curves no differences were found in diagnostic performance of the three enzymes. Use of combinations of different enzymes had no advantage over single enzyme determination using discrimination analysis for evaluation. The highest efficiency was for all three enzymes 0.991 (95% confidence limits: 0.983-0.995) and for all three enzymes the discrimination value giving this efficiency was several times the upper limit of reference range: 1 779 micrograms/l for cathodic trypsin-like immunoreactivity, 831 U/l for pancreatic isoamylase and 316 micrograms/l for pancreatic lipase. None of the enzymes had any prognostic value at admission in predicting a mild or severe attack of acute pancreatitis. In conclusion, no single enzyme or combination of enzymes had any diagnostic advantage for acute pancreatitis in patients with acute abdominal pain. Thus selection of one of the three enzymes as diagnostic test of acute pancreatitis is to be based on considerations such as economy, methodological simplicity, possibility of automated assay and the time-consumption at the assay.

Abdomen↗
PubMed1987

Indomethacin pretreatment inhibits fever after anodal, but not cathodal, medial preoptic lesions in rats.

Pretreatment with indomethacin (15 mg/kg) prevented the fever occurring in unanesthetized rats immediately after unilateral anodal electrolytic lesions of the medial preoptic area. The drug had no effect on the fever if given before cathodal lesions. If given after the lesions, when the fever had begun to develop, indomethacin lowered anodal body temperature back to baseline for varied lengths of time and attenuated cathodal fever.

Animals↗
PubMed1987

Localization of the main noradrenergic neuron groups in the pons and medulla of the rabbit and the importance of cathodal lesions for prolonged survival.

Methods for stereotaxically localizing the major noradrenergic (NA) cell groups (i.e. A1, A2, A5 and A6 + A7) in the rabbit are described. Using a modified Kopf head holder we used surface landmarks including the obex for making lesions of the A1 and A2 cells in the medulla. Localization of the pontine cell groups was done by mapping intracerebral structures including the facial nerve for A5 and the motor nucleus of the trigeminal nerve for A6 + A7. In the initial experiments we made A1 lesions by passing anodal currents through stainless steel electrodes, which was associated with pulmonary oedema, neurological complications and a high mortality. This syndrome was probably related to toxic effects of ferric ion deposition, and disappeared when cathodal currents were employed. We have now made 106 bilateral cathodal lesions in the different groups, with a 20% intraoperative mortality. But virtually all survivors remained indefinitely in clinically good condition for the 2-4 weeks duration of our experiments. In 65 of these rabbits we achieved greater than 75% of NA cell destruction (average 84%). From the cardiovascular viewpoint 'non-specific' damage by the lesions was relatively small, except after A2 lesions where there was some impairment in the baroreceptor-heart rate reflex, though a considerable amount of residual function remained.

Animals↗
PubMed1982

The use of a cathodic antigen in the immunoelectrophoretic serodiagnosis of Echinococcus granulosus in sheep.

An antigen was prepared from purified sheep hydatid-cyst fluid by gel-filtration on Sephadex G-200 followed by chromatography on DEAE-cellulose. In each case the first-peak material was used. This antigen, which migrated cathodically, was concentrated and used in immunoelectrophoretic analyses of 4X concentrated sera from sheep experimentally and naturally infected with Echinococcus granulosus and from uninfected sheep. Of 34 sheep with E. granulosus infection 31 were positive with the cathodic antigen while of 85 sheep with E. granulosus 8 were (falsely) positive. Many false positives appeared to be associated with heavy infections of Taenia ovis or T. hydatigena larvae. The "arc 5' immunoelectrophoresis test, which is the most specific immuno-diagnostic test for echinococcus infection in humans, was not able to specifically identify E. granulosus infections in sheep.

Animals↗
PubMed1981

Anodic migration of actin and increased levels of a cathodic fibronectin among the cytoskeletal changes that correlate with increased cell adherence in liver epitheloid tumor cells.

Liver epitheloid tumor cells exposed to iododeoxyuridine revealed increased resistance to detachment from their growth substratum when exposed to low levels of EDTA. Two-dimensional analysis of the Triton-X-100 insoluble cytoskeleton from cells grown with iododeoxyuridine revealed an increased level of cathodic fibronectin and a more anodic migration of actin-like components concurrent with the reduced expression of an anodic 50K component and of a cathodic 60K component.

Actins↗
PubMed2004

Molecular modeling and small angle X-ray scattering studies of Hoplosternum littorale cathodic haemoglobin.

Considerable interest is currently focused on fish haemoglobins in order to identify the structural basis for their diversity of functional behavior. Hoplosternum littorale is a catfish that presents bimodal gill (water)/gut (air)-breathing, which allows this species to survive in waters with low oxygen content. The hemolysate of this fish showed the presence of two main haemoglobins, cathodic and anodic. This work describes structural features analyzed here by integration of molecular modeling with small angle X-ray scattering. Here is described a molecular model for the cathodic haemoglobin in the unliganded and liganded states. The models were determined by molecular modeling based on the high-resolution crystal structure of fish haemoglobins. The structural models for both forms of H. littorale haemoglobin were compared to human haemoglobin.

Amino Acid Sequence↗
PubMed2005

On the stability of the "wired" bilirubin oxidase oxygen cathode in serum.

Oxygen is electroreduced to water on the "wired" bilirubin oxidase (w-BOD) catalyst at a considerably lesser potential than on pure platinum. The w-BOD catalyst could be of value in an implantable glucose-O2 biofuel cell, operating living tissue, if it were stable in serum. We found, however, that w-BOD loses its activity in a few hours in the combined presence of the urate and O2, both of which are normal serum constituents (Bioelectrochemistry, 2004, 65, 83-88). Here we report a second major instability: When the disconnected w-BOD cathode is allowed, in the absence of urate, to poise itself at the potential of the O2/H2O half cell at pH 7.2, it loses its activity rapidly. Unlike the urate/O2 caused loss, this loss can be avoided either by applying a potential that is reducing relative to the O2/H2O half-cell potential, or by excluding O2 and adding a mildly reducing reagent, such as urate. The w-BOD cathode can be stored, therefore, in deoxygenated serum, which contains urate.

Animals↗
PubMed2006

Bioactivity and cytocompatibility of zirconia (ZrO(2)) films fabricated by cathodic arc deposition.

Zirconium oxide thin films were fabricated on silicon wafers using a filtered cathodic arc system in concert with oxygen plasma. The structure and phase composition of the zirconium oxide thin films were characterized by atomic force microscopy (AFM), X-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS), and transmission electron microscopy (TEM). The bioactivity was assessed by investigating the formation of apatite on the film surface after soaking in simulated body fluids. Bone marrow mesenchymal stem cells (BMMSC) were used to further evaluate the cytocompatibility of the materials. The results indicate that the films are composed of stoichiometric ZrO(2) and the composition is quite uniform throughout the thickness. Bone-like apatite can be formed on the surface of the ZrO(2) thin film in our SBF immersion experiments, suggesting that the surface is bioactive. The outermost layer of the ZrO(2) thin film comprises nano-sized particles that can be identified by AFM images taken on the thin film surface and TEM micrographs obtained from the interface between the ZrO(2) thin film and apatite layer. The nanostructured surface is believed to be the key factor that apatite is induced to precipitate on the surface. Bone marrow mesenchymal stem cells are observed to grow and proliferate in good states on the film surface. Our results show that ZrO(2) thin films fabricated by cathodic arc deposition exhibit favorable bioactivity and cytocompatibility.

Animals↗
PubMed2006

A biofilm enhanced miniature microbial fuel cell using Shewanella oneidensis DSP10 and oxygen reduction cathodes.

A miniature-microbial fuel cell (mini-MFC, chamber volume: 1.2 mL) was used to monitor biofilm development from a pure culture of Shewanella oneidensis DSP10 on graphite felt (GF) under minimal nutrient conditions. ESEM evidence of biofilm formation on GF is supported by substantial power density (per device cross-section) from the mini-MFC when using an acellular minimal media anolyte (1500 mW/m2). These experiments demonstrate that power density per volume for a biofilm flow reactor MFC should be calculated using the anode chamber volume alone (250W/m3), rather than with the full anolyte volume. Two oxygen reduction cathodes (uncoated GF or a Pt/vulcanized carbon coating on GF) were also compared to a cathode using uncoated GF and a 50mM ferricyanide catholyte solution. The Pt/C-GF (2-4% Pt by mass) electrodes with liquid cultures of DSP10 produced one order of magnitude larger power density (150W/m3) than bare graphite felt (12W/m3) in this design. These advances are some of the required modifications to enable the mini-MFC to be used in real-time, long-term environmental power generating situations.

Bioelectric Energy Sources↗
PubMed2006

Anodal vs cathodal stimulation of motor cortex: a modeling study.

OBJECTIVE: To explore the effects of electrical stimulation performed by an anode, a cathode or a bipole positioned over the motor cortex for chronic pain management. METHODS: A realistic 3D volume conductor model of the human precentral gyrus (motor cortex) was used to calculate the stimulus-induced electrical field. The subsequent response of neural elements in the precentral gyrus and in the anterior wall and lip of the central sulcus was simulated using compartmental neuron models including the axon, soma and dendritic trunk. RESULTS: While neural elements perpendicular to the electrode surface are preferentially excited by anodal stimulation, cathodal stimulation excites those with a direction component parallel to its surface. When stimulating bipolarly, the excitation of neural elements parallel to the bipole axis is additionally facilitated. The polarity of the contact over the precentral gyrus determines the predominant response. Inclusion of the soma-dendritic model generally reduces the excitation threshold as compared to simple axon model. CONCLUSIONS: Electrode polarity and electrode position over the precentral gyrus and central sulcus have a large and distinct influence on the response of cortical neural elements to stimuli. SIGNIFICANCE: Modeling studies like this can help to identify the effects of electrical stimulation on cortical neural tissue, elucidate mechanisms of action and ultimately to optimize the therapy.

Axons↗
PubMed2006

Surface oxidation of polyethylene using an atmospheric pressure glow discharge with liquid electrolyte cathode.

This study investigated the action of an atmospheric pressure air glow discharge (APGD) with aqueous electrolyte cathode onto the surface of polyethylene (PE) films. Distilled water and aqueous solutions of KCl and HCl were utilized as a cathode. The surface properties of PE were characterized by contact angle measurement followed by surface free energy calculation, Fourier transform infrared by attenuated total reflectance (FTIR-ATR), and XPS. After treating the PE surface, we observed OH groups, CO groups in ester, ketone, and carboxyl groups, and CO groups in unsaturated ketones and aldehydes. For a treatment time of 20 min and a discharge current of 40 mA, atomic concentrations of O and N were 12% and 2%, respectively, under distilled water application. Modification processes were able to improve the surface free energy of PE.

Journal Article↗
PubMed2005

The dissolution mechanism of cathodic active materials of spent Zn-Mn batteries in HCl.

The cathodic active materials of spent Zn-Mn batteries are complicated. The majority materials that they contain are Mn(OH)(2), Mn(2)O(4), lambda-Mn(2)O(2), ZnMn(2)O(4), Zn(NH(3))(2)Cl(2), [Zn(OH)(2)](4).ZnCl(2), etc. Dissolving these kinds of materials is important to the environmental pollution control and materials recycle. In present paper we investigated the dissolution mechanism of the cathodic active materials in HCl by testing the factors that can influence the dissolution procedure, including temperature, time, and the concentration of HCl and H(2)O(2). Our results showed that both neutralization and oxidation-reduction reactions occurred in the dissolution process, and that H(2)O(2) had a great effect on the dissolution efficiency.

Hydrochloric Acid↗
PubMed2005

Linear scan voltammetric indirect determination of Al(III) by the catalytic cathodic response of norepinephrine at the hanging mercury drop electrode.

The biological effects of aluminum (Al) have received much attention in recent years. Al is of basic relevance as concern with its reactivity and bioavailability. In this paper, the electrochemical behaviors of norepinephrine (NE) in the absence and presence of Al(III) at the hanging mercury drop electrode have been studied and applied to the practical analysis. Highly selective catalytic cathodic peak of NE is yielded by linear scan voltammetry (LSV) at -1.32 V (vs. SCE). A linear relationship holds between the cathodic peak current and the Al(III) concentration. It has been successfully applied to the determination of Al(III) in real waters and synthetic biological samples with satisfying results, which are in accordance with those obtained by ICP-AES method. The electrochemical properties and the mechanisms of the peaks in the presence and absence of Al(III) have been explored. The results show that they are irreversible adsorptive hydrogen catalytic waves. These studies not only enrich the methods of determining Al, but also lay foundations of further understanding of the mechanisms of neurodementia.

Aluminum↗
PubMed2006

The characterization of waste cathode-ray tube glass.

New re-use applications are needed to address the relatively large quantity of waste electronic products generated in the world. Cathode-ray tubes (CRTs) from computer monitors and TV sets are a large component of such waste. The three glass components of CRTs are the funnel, panel and neck, which are produced by various manufacturers and are now collected by asset-recovery centres. In this paper, we characterize waste funnel and panel glass from dismantled cathode-ray tubes with a view to assisting the development of new re-use applications. The heavy metal (lead, barium, and strontium) content of such glass represents an acute risk to the environment. Our results of the chemical composition for different kinds of waste CRT glass including black & white and color CRTs show that CRT glass from different producers have generally similar chemical compositions. In particular, the compositions of funnel and panel black & white CRT glass are similar, but are different to those of panel and funnel color CRT glass. We also measured the following specific properties of each type of CRT glass: density, glass transition temperature, and linear coefficient of thermal expansion. It was found that the coefficients of thermal expansion of CRT glass do not vary with their composition. In contrast, the measured densities and glass transition temperatures do vary with composition. On the basis of our experimental data and data found in the literature, we outline the main properties of several waste CRT glass currently in circulation. The aim of this study was to provide the data required to determine if this kind of waste could be entirely (or partially) re-used and to aid the search for promising methods of treatment.

Computer Terminals↗
PubMed2002

Cathodic electrodeposition of ceramic and organoceramic materials. Fundamental aspects.

Electrodeposition of ceramic materials can be performed by electrophoretic (EPD) or electrolytic (ELD) deposition. Electrophoretic deposition is achieved via motion of charged particles towards an electrode under an applied electric field. Electrolytic deposition produces colloidal particles in cathodic reactions for subsequent deposition. Various electrochemical strategies and deposition mechanisms have been developed for electrodeposition of ceramic and organoceramic films, and are discussed in the present article. Electrode-position of ceramic and organoceramic materials includes mass transport, accumulation of particles near the electrode and their coagulation to form a cathodic deposit. Various types of interparticle forces that govern colloidal stability in the absence and presence of processing additives are discussed. Novel theoretical contributions towards an interpretation of particle coagulation near the electrode surface are reviewed. Background information is given on the methods of particle charging, stabilization of colloids in aqueous and non-aqueous media, electrophoretic mobility of ceramic particles and polyelectrolytes, and electrode reactions. This review also covers recent developments in the electrodeposition of ceramic and organoceramic materials.

Journal Article↗
PubMed2003

Formation of a percolating cluster in films prepared by cathodic electrodeposition of a mixture of lower and higher molecular weight epoxy-amine adducts.

The electrodeposition behavior of blends of primary dispersions of a lower and a higher molecular weight epoxy-amine adduct has been investigated. The throwing power of the above-mentioned blends showed a voltage-dependent critical composition at which the throwing power dropped to a much lower value. This was assigned to the formation of an infinite conducting cluster, the extension of which is dependent on the rate of the electrocoagulation process at the cathode boundary. The random resistor network approach of Stauffer (RRNS) and the random resistor network approach of Miller and Abrahams (RRNMA) were applied to the experimental data with high correlations (r2=0.9314 and 0.9699). The percolating cluster formed within the film, however, gave a critical exponent of conductivity equal to 1.1028, much less than expected from a classical three-dimensional lattice (i.e., 1.5-2.0). This discrepancy was explained in terms of the changed behavior of the film resulting from the bubbles formed near the cathode and its effect on the infinite conducting cluster.

Journal Article↗
PubMed2002

Electron-electron interactions in cathode objective lenses.

The impact of electron-electron interactions on the electron-optical performance of imaging cathode objective lenses is evaluated. Three types of cathode objectives are considered: decelerating and accelerating electrostatic, and combined magnetic lenses. The beam blur is calculated for field sizes ranging from 50 microm x 50 microm to 500 microm x 500 microm and total beam currents ranging from 200 nA to 20 microA. The functional dependence of the beam blur upon electron beam current and current density is elucidated in detail.

Journal Article↗
PubMed2001

Multiple isoforms and an unusual cathodic isoform of creatine kinase from channel catfish (Ictalurus punctatus).

In vertebrates, the creatine kinase (CK) family consists of two cytosolic and two mitochondrial isoforms. The two cytosolic isoforms are the muscle type (M-CK) and the brain type (B-CK). Here we report multiple CK isoenzymes in the diploid channel catfish (Ictalurus punctatus) with one unusual cathodic isoform that was previously found only in pathological situations in human. The cathodic CK isoform existed only in the channel catfish stomach, ovary, and spleen, but not in any other species analyzed such as tilapia, smallmouth bass, chicken, or rat. Two genes encode the multiple forms of the channel catfish M-CK cDNAs. M-CK1 has three alleles, M-CK1.1, M-CK1.2, and M-CK1.3, while M-CK2 has just one allele as determined by analysis of 17 cDNA clones and by allele-specific PCR. M-CK1 encodes a protein of 381 amino acids and the M-CK2 cDNA encodes a protein of 380 amino acids. The two cDNAs shared an 86% identity and both have the nine diagnostic boxes for cytosolic CKs and thus are of cytosolic origin. The M-CK1 gene was isolated, sequenced, and characterized and its promoter should be useful for transgenic research for muscle-specific expression.

Amino Acid Sequence↗