The major function of human transferrin is to deliver iron from the bloodstream to actively dividing cells. Upon iron release, the protein changes its conformation from 'closed' to 'open'. Extensive studies in vitro indicate that iron release from transferrin is very complex and involves many factors, including pH, the chelator used, an anion effect, temperature, receptor binding and intra-lobe...

Physicochemical properties, including particle size, zeta potential, and drug release behavior, affect targeting efficiency, cellular uptake, and antitumor effect of nanocarriers in a formulated drug-delivery system. In this study, a novel stepwise pH-responsive nanodrug delivery system was developed to efficiently deliver and significantly promote the therapeutic effect of doxorubicin (DOX). T...

During maturation of oocytes, Cl(-) conductance (G(Cl)) oscillates and intracellular pH (pH(i)) increases. Elevating pH(i) permits the protein synthesis essential to maturation. To examine whether changes in G(Cl) and pH(i) are coupled, the Cl(-) channel ClC-0 was heterologously expressed. Overexpressing ClC-0 elevates pH(i), decreases intracellular Cl(-) concentration ([Cl(-)](i)), and reduces...

Methane (CH4) production varies greatly among different types of peatlands along an ombrotrophice minerotrophic hydrogeomorphic gradient. pH is thought to be a dominant control over observed differences in CH4 production across sites, and previous pH manipulation experiments have verified the inhibitory effect of low pH on CH4 production. In this experiment, we asked (i) if the major effect of ...

background gastroesophageal reflux disease (gerd) is a common problem seen in pediatrics and adolescents. the bravo tm ph monitoring system is a capsule that detects and quantifies the severity of reflux disease. this test is also valuable for evaluation of patients with extra-gastrointestinal manifestations of gerd such as asthma, chronic cough, hoarseness, aspiration pneumonia, and pre/post f...

In order to examine the mechanism of basolateral membrane H+/OH-/HCO-3 transport, a method was developed for the measurement of cell pH in the vivo doubly microperfused rat proximal convoluted tubule. A pH-sensitive fluorescein derivative, (2',7')-bis(carboxyethyl)-(5,6)-carboxyfluorescein, was loaded into cells and relative changes in fluorescence at two excitation wavelengths were followed. C...

The hybridization of a human and mouse cell was strikingly pH-dependent, with a well defined optimum at (about) pH 7.6-8.0. The yield of hybrid cell colonies (1 per 500-2000 heterokaryocytes) was several hundred times greater than that obtained at pH 6.8-7.2. Although there was a significant effect on the efficiency of cell fusion, the critical time for the pH effect was in the first 4-8 days a...

To study the leakage at different solution pH values, IgG Sepharose 6FF®, a commercially available immunoadsorbent, was used as a model. The leaked substance consists of three parts: (1) ligands and its fragments; (2) ligands plus matrix fragments in which ligands are chemically attached to the adsorbent matrix; and (3) matrix fragments. Buffer solution pH values had a great effect on both the ...

The effect of different anions on the sensitivity of Vero cells to ricin was investigated. The cells were equally sensitive to ricin when NaCl was replaced by NaBr, NaI, Na2SO4 or with iso-osmotic concentrations of mannitol. In contrast, NaSCN and NaClO4 strongly protected against ricin at pH 7.2, but not at pH 7.6. The possibility that the protective effect is due to the ability of chaotropic ...

This study was conducted to elucidate the effect of pH on the toxicity of cadmium, cobalt and copper to the green alga Scenedesmus bijuga. The results revealed that the growth of Scenedesmus bijuga increased with increasing pH. However, the accumulation, the accumulation factor and the amount of free ionic forms of each metal decreased. Generally, it appears that the metals tested exert more to...