The mechanism of cephalosporin‐induced hypoprothrombinemia has been investigated in hospitalized patients, with respect to cephalosporin structure, vitamin K metabolism, and status. Cephalosporins containing side chains N‐methylthiotetrazole (latamoxef, cefmenoxime, cefoperazone, cefotetan, cefamandole) or methyl‐thiadiazole (cefazolin) all caused the transient plasma appearance 1 2,3‐epoxide response a 10‐mg intravenous dose , whereas two cephalosporins without heterocyclic chain...

One hundred and seven healthy, breast fed infants received 1 mg vitamin K1 either at birth (orally or intramuscularly) with the first feed (orally). Venous blood samples collected in next 24 hours were assayed for plasma K1. In babies given orally birth, peak median concentration (73 ng/ml) occurred four hours. By concentrations had fallen to 23 ng/ml 35 groups feed, respectively; this difference was not, however, significant. Plasma after intramuscular injection exceeded those oral all...

Rats given a low-fibre diet based on boiled white rice developed symptoms of severe vitamin K deficiency within 23 d. Inclusion autoclaved black-eye beans ( Vigna unguiculata ) in the prevented bleeding syndrome. To test hypothesis that resulted from low phylloquinone intake exacerbated by inadequate production menaquinones enteric bacteria, follow-up experiment was carried out which groups rats were an all-rice diet, rice+beans or stock diet. allrice had significantly lower faecal...

High-performance liquid chromatography (HPLC) with dual-electrode electrochemical detection has been used, in the redox mode, to determine normal and sub-normal circulating plasma levels of phylloquinone (vitamin K1) concentrations down 20 pg ml–1 have measured plasma. The coefficient variation, for endogenous levels, was 10%(mean 330 ml–1; n= 6). When compared a single glassy carbon electrode, operated reductive sensitivity cell greater by at least an order magnitude. Thus volume required...

Neural prosthetic interfaces based upon penetrating microelectrode devices have broadened our understanding of the brain and shown promise for restoring neurological functions lost to disease, stroke, or injury. However, eventual viability such use in treatment dysfunction may be ultimately constrained by intrinsic brittleness silicon, material most commonly used manufacture microelectrodes. This creates predisposition catastrophic fracture, which adversely affect reliability safety devices,...

Cyclic voltammetry has been used to study the reduction of phylloquinone (2-methyl-3-phytyl-1,4-naphthoquinone)(vitamin K1) at a planar glassy-carbon electrode. The reaction was found be quasi-reversible with adsorption product, but not reactant, taking place electrode surface. Liquid chromatography electrochemical detection determine endogenous levels in human plasma. normal range 0.08–1.24 ng ml–1; mean value 0.41 ml–1. assay shown about three times as sensitive previous liquid...

A simple high-performance liquid chromatographic assay for the measurement of quinine, hydroxychloroquine, chloroquine, and desethylchloroquine in small volumes (50-200 microL) serum, whole blood, or filter paper-adsorbed dry blood was developed. The analytes are isolated by liquid-liquid extraction chromatographed on a sulfophenylpropyl-modified silica column under isocratic conditions. effluent is monitored fluorimetry (excitation wavelength, 215 nm; no emission filter). limit quantitation...

The ontogeny of the iodothyronine deiodinase systems has been studied by several investigators in recent years, but our understanding subject is far from complete. present study was conducted to obtain kinetic information concerning 5' (5'D) and 5 (5D) activities fetal rat liver intestine, examine reduced glutathione (GSH)-activated 5'D activity two tissues. When dithiothreitol (DTT) used as cofactor concentrations up 100 DIM, not clearly detected or intestine until day 16 gestation....

A method is described for the determination of terbutaline and salbutamol in plasma from patients given maximal therapy brittle asthma. The analytes were isolated by solid phase extraction on alkali-treated Bond-Elut, unmodified, silica columns measured high performance liquid chromatography with fluorescence detection (excitation wavelength 200 nm). limits a 1 mL sample containing microgram/L 2.5 micrograms/L, respectively. intra-assay precision (CV) samples 25 micrograms/L was 3.6 5.0%...

This article describes advances in thermionic and photoemission materials applications dating back to the work on emission by Guthrie 1873 photoelectric effect Hertz 1887. Thermionic has been employed for electron beam generation from Edison's with light bulb modern day technologies such as scanning transmission microscopy. The utilized common devices cameras photocopiers while photovoltaic cells continue be widely successful further researched. Limitations device efficiency have thus far...

A simple method for the measurement of clozapine and its N-desmethyl metabolite in human plasma or serum by high performance liquid chromatography is described. An internal standard (aqueous nortriptyline, 4 mg/L) (50 microL) Tris buffer (2 mol/L, pH 10.6) (100 are added to plasma/serum (200 analytes extracted into methyl tert-butyl ether microL). The extracts analysed on a 150 mm column containing Spherisorb S5SCX using methanol ammonium perchlorate (35 mmol/L, 6.7) as eluent at flow rate...

Two patients with low random serum vitamin K1 concentrations but normal prothrombin times and biological assays of the K dependent coagulation proteins were treated an N-methyl-thiotetrazole cephalosporin (cefotetan) postoperatively. Four to six days later both developed a prolonged time noticeable specific lowering clotting activities factors II, VII, IX X, though remained unchanged. Crossed immunoelectrophoresis showed appearance second peak corresponding descarboxyprothrombin (PIVKA II)....

Micro-scale brain-machine interface (BMI) devices have provided an opportunity for direct probing of neural function and also shown significant promise restoring neurological functions lost to stroke, injury, or disease. However, the eventual clinical translation such may be hampered by limitations associated with materials commonly used their fabrication, e.g. brittleness silicon, insufficient rigidity polymeric devices, unproven chronic biocompatibility both. Herein, we report, first time,...

Direct recording from sequential processing stations within the brain has provided opportunity for enhancing understanding of important neural circuits, such as corticothalamic loops underlying auditory, visual, and somatosensory processing. However, common reliance upon microwire-based electrodes to perform recordings often necessitates complex surgeries increases trauma tissues. This paper reports development titanium-based, microfabricated, microelectrode devices designed address these...

SUMMARY The aim of this study was to determine whether patients' tolerance upper gastrointestinal endoscopy is related the dose lignocaine spray used for oropharyngeal anaesthesia and measure plasma concentrations at these doses. Sixty consecutive patients undergoing routine with sedation were randomized receive 50 mg (Group A), 100 B) or 200 C). Patient, endoscopist nurse unaware variation in used. Each patient's intubation remainder gastroscopy assessed independently by patient, nurse,...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation Patrick T. McCarthy, Scott J. Vander Laan, David B. Janes, Timothy S. Fisher; Photonically excited electron emission from modified graphitic nanopetal arrays. Journal of Applied Physics 21 May 2013; 113 (19): 193710. https://doi.org/10.1063/1.4805038 Download citation file: Ris (Zotero) Reference Manager...

This paper reports on characterization techniques for electron emission from potassium-intercalated boron nitride modified graphitic petals. Carbon-based materials offer potentially good performance in applications owing to high thermal stability and a wide range of nanostructures that increase current via field enhancement. Furthermore, potassium adsorption intercalation carbon-based nanoscale emitters decreases work functions approximately 4.6 eV as low 2.0 eV. In this study, modifications...

AbstractWe have investigated the effects of iron overload in vivo on tocopherol levels and extent lipid peroxidation rat liver microsomes their response to subsequent oxidative stress vitro. The results demonstrate a direct correlation between consumption antioxidant defences induction malondialdehyde production prepared from iron-loaded rats. data are consistent with requirement for (II)/iron (III) ratios control microsomes.Key Words: α-tocopherolmalondialdehydehplciron overloadoxidative