Search results for "buffer"
showing 10 items of 230 documents
Ruthenium red staining of polyanion containing structures in sections from epoxy-resin embedded tissues
1984
Summary Staining by ruthenium red (0.5 mg/ml in borate buffer at pH = 9.2) has been used for light and electron microscopic visualization of polyanion containing structures in sections from glutaraldehyde-fixed, epoxy-embedded tissues. This staining technique can be applied in a simple and rapid way, showing the reactive cell components with suitable resolution and contrast. Preliminary spectrophotometric studies show the correspondence in absorption characteristics of the dye which is bound to polyanions in situ or in vitro .
Epizootic of dolphin morbillivirus on the Catalonian Mediterranean coast in 2007
2011
BETWEEN 1990 and 1992, thousands of striped dolphins (Stenella coeruleoalba) stranded along the Mediterranean coast due to a newly described virus, the dolphin morbillivirus (DMV) (Domingo and others 1990, 1992). DMV is one of the several morbilliviruses that have killed marine mammals worldwide since 1987 (Di Guardo and others 2005). A new DMV epizootic has been recently confirmed from the Mediterranean Spanish and French coasts during 2007 to 2008 (Fernández and others 2008, Raga and others 2008, Keck and others 2010). This short communication describes the pathological findings associated with DMV infection and secondary infections, observed during this epizootic on the Mediterranean coa…
Efficacy of Buffered Hypertonic Saline Nasal Irrigation for Nasal Symptoms in Children with Seasonal Allergic Rhinitis: A Randomized Controlled Trial
2017
<b><i>Background:</i></b> Saline nasal irrigation is labelled as an add-on treatment in patients with allergic rhinitis (AR). The primary aim of this study was to compare the efficacy of 21-day use of buffered hypertonic saline (BHS) versus normal saline solution (NSS) on reducing nasal symptoms in children with seasonal AR (SAR). Comparing their efficacy on nasal cytology counts (NCC), quality of life, and sleep quality was the secondary aim. <b><i>Methods:</i></b> In this 21-day,<b> </b>open-label, randomized controlled study, 36 SAR children (aged 6-13 years) with a Total 5 Symptom Score (T5SS) ≥5 received twice-daily BHS or NSS…
Kidney donors and kidney transplants have abnormal aminothiol redox status, and are at increased risk of oxidative stress and reduced redox buffer ca…
2013
Abstract Objective Living kidney donors have been part of a successful kidney transplant programme in Norway for almost 50 years. Glomerular filtration rates (GFRs) have tended to remain stable at about 70% of pre-donation levels. Plasma total homocysteine (Hcy) has an inverse relationship to kidney function, and previous reports indicate elevated levels of Hcy in kidney donors. We wanted to examine the most important plasma aminothiols in kidney donors, i.e. Hcy, cysteine (Cys) and cysteinylglycine (CG) with their redox species. The aminothiol redox-system appears to be an integral part of the extracellular antioxidant defence system in the body. Design and methods Plasma concentrations of…
Uptake and metabolism of choline by rat brain after acute choline administration.
1992
The present study is concerned with the uptake and metabolism of choline by the rat brain. Intraperitoneal administration of choline chloride (4-60 mg/kg) caused a dose-dependent elevation of the plasma choline concentration from 11.8 to up to 165.2 microM within 10 min and the reversal of the negative arteriovenous difference (AVD) of choline across the brain to positive values at plasma choline levels of greater than 23 microM. Net choline release and uptake were linearly dependent on the plasma choline level in the physiological range of 10-50 microM, whereas the CSF choline level was significantly increased only at plasma choline levels of greater than 50 microM. The bolus injection of …
Binding of urate and caffeine to hemocyanin of the lobster Homarus vulgaris (E.) as studied by isothermal titration calorimetry.
2000
Hemocyanin serves as an oxygen carrier in the hemolymph of the European lobster Homarus vulgaris. The oxygen binding behavior of the pigment is modulated by metabolic effectors such as lactate and urate. Urate and caffeine binding to 12-meric hemocyanin (H. vulgaris) was studied using isothermal titration calorimetry (ITC). Binding isotherms were determined for fully oxygenated hemocyanin between pH 7.55 and 8.15. No pH dependence of the binding parameters could be found for either effector. Since the magnitude of the Bohr effect depends on the urate concentration, the absence of any pH dependence of urate and caffeine binding to oxygenated hemocyanin suggests two conformations of the pigme…
Market risk reporting in banking overcoming the limits of IAS/IFRS and Basel regulation
2017
Market risk in banking activity is becoming a more severe issue day by day for several reasons. Analysing it from a regulatory point of view is fundamental for assessing whether or not banks are in the conditions of disclosing a satisfactory degree of information about their market risk exposure. The two regulatory constraints to consider are International Accounting Standards (IAS/IFRS) and the Basel regulation. Both of them seem to put too many constraints on banks. They turn out to be over-over-regulated. Even if regulators put many efforts in trying to provide a useful regulation for banks' risk reporting and capital adequacy, we are still far from a good regulation. The regulatory proc…
Mass Transport Analysis of the Enhanced Buffer Capacity of the Bicarbonate-CO2 Buffer in a Phase-Heterogenous System: Physiological and Pharmaceutica…
2018
The bicarbonate buffer capacity is usually considered in a phase-homogeneous system, at equilibrium, with no CO2 transfer between the liquid buffer phase and another phase. However, typically, an in vitro bicarbonate buffer-based system is a phase-heterogeneous system, as it entails continuously sparging (bubbling) the dissolution medium with CO2 in a gas mixture, at constant ratio, to maintain a constant partial pressure of CO2 (g) and CO2(aq) molarity at a prescribed value, with CO2 diffusing freely between the gas and the aqueous phases. The human gastrointestinal tract is also a phase-heterogeneous system, with CO2 diffusing across the mucosal membrane into the mesenteric arterial blood…
Essential features of optical processes in neon-buffered submicron-thin Rb vapor cell
2010
A new submicron thin cell (STC) filled with Rb and neon gas is developed and comparison of resonant absorption with STC containing pure Rb is provided. The effect of collapse and revival of Dicke-type narrowing is still observable for the thickness L = lambda /2 and L = lambda , where lambda is a resonant laser wavelength 794 nm (D(1) line). For an ordinary Rb cm-size cell with addition of buffer gas, the velocity selective optical pumping/saturation (VSOP) resonances in saturated absorption spectra are fully suppressed if neon pressure0.5 Torr. A spectacular difference is that for L = lambda , VSOP resonances are still observable even when neon pressure isor = 6 Torr. Narrow fluorescence s…
Highly activated screen-printed carbon electrodes by electrochemical treatment with hydrogen peroxide
2018
An easy effective method for the activation of commercial screen-printed carbon electrodes (SPCEs) using H2O2 is presented to enhance sensing performances of carbon ink. Electrochemical activation consists of 25 repetitive voltammetric cycles at 10 mV s−1 using 10 mM H2O2 in phosphate buffer (pH 7). This treatment allowed us to reach a sensitivity of 0.24 ± 0.01 μA μM−1 cm−2 for the electroanalysis of H2O2, which is 140-fold higher than that of untreated SPCEs and 6-fold more than screen-printed platinum electrodes (SPPtEs). Electrode surface properties were characterized by SEM, EIS and XPS. The results revealed atomic level changes at the electrode surface, with the introduction of new ca…