Scanning Electron Microscopy and Transmission Electron Microscopy Aspects of Synergistic Antitumor Activity of Vitamin C - Vitamin K3 Combinations Against Human Prostatic Carcinoma Cells

A MTT/formazan assay was used to evaluate the antitumor activity of vitamin C (Vit C), vitamin K3 (Vit K3), or vitamin C:vitamin K3 combinations against a human prostatic carcinoma cell line (DU145). Both Vit C and Vit K3 alone exhibited antitumor activity, but only at elevated doses. When Vit C and Vit K3 were combined at a C:K3 ratio of 100:1 and administered to the carcinoma cells, the 50% cytotoxic concentrations (CD50) of the vitamins decreased 10-to 60-fold. Subsequently, the DU145 cells were examined with transmission and scanning electron microscopy (TEM and SEM) following a 1 hour treatment with Vit C, Vit K3, or Vit C/K3 combined at their 50% cytotoxic dose. Our morphological data suggest that vitamin treatment with individual vitamins affects the cytoskeleton, the mitochondria, and other membranous components of the cell. Treatment with the vitamin combination appears to potentiate the effects of the individual vitamin treatment. Specifically, there are abundant necrotic cells. The surviving cells display morphological defects characteristic of cell injury

Storylines of family medicine IX: people and places—diverse populations and locations of care

Storylines of Family Medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine as interpreted by individual family physicians and medical educators in the USA and elsewhere around the world. In 'IX: people and places-diverse populations and locations of care', authors address the following themes: 'LGBTQIA+health in family medicine', 'A family medicine approach to substance use disorders', 'Shameless medicine for people experiencing homelessness', '''Difficult" encounters-finding the person behind the patient', 'Attending to patients with medically unexplained symptoms', 'Making house calls and home visits', 'Family physicians in the procedure room', 'Robust rural family medicine' and 'Full-spectrum family medicine'. May readers appreciate the breadth of family medicine in these essays

Experimental evaluation of in situ CO2-water-rock reactions during CO2injection in basaltic rocks: Implications for geological CO2 sequestration

Deep aquifers are potential long-term storage sites for anthropogenic CO2 emissions. The retention time and environmental safety of the injected CO2 depend on geologic and physical factors and on the chemical reactions between the CO2, the aquifer water, and the host rocks. The pH buffer capacity of the aquifer water and the acid neutralization potential of the host rocks are important factors for the permanent stabilization of the injected CO2. Mafic rocks, such as basalt, which primarily consists of Ca, Mg silicate minerals, have a high acid neutralization capacity by providing alkaline earth elements that form stable carbonate minerals. The carbonate minerals formed thus sequester CO2 in a chemically stable and environmentally benign form. In this study, we present results from a small-scale CO2 injection test in mafic and metasedimentary rocks. The injection test was conducted using a single-well push-pull test strategy. CO2 saturated water (pH = 3.5) was injected into a hydraulically isolated and permeable aquifer interval to study the acid neutralization capacity of Ca, Mg silicate rocks and to estimate in situ cation release rates. Release rates for Ca, Mg, and Na were calculated by use of solute compositions of water samples retrieved after the CO2 injection, the incubation time of the injected solution within the aquifer, and geometric estimates of the reactive surface area of the host rocks. Our results confirm rapid acid neutralization rates and water-rock reactions sufficient for safe and permanent storage of CO2. Carbonic acid was neutralized within hours of injection into a permeable mafic aquifer by two processes: mixing between the injected solution and the aquifer water, and water-rock reactions. Calculated cation release rates decrease with increasing pH that is confirmed by laboratory-based experiments. Large differences between release rates obtained from the field and laboratory experiments may be mainly due to uncertainties in the estimation of the reactive surface area in the field experiment and in hydrological and geological factors. Our results underscore the importance of defining bulk rock dissolution rates under in situ conditions in order to evaluate target formations for permanent mineral sequestration of carbon dioxide

The role of H2O in the carbonation of forsterite in supercritical CO2

The effect of variable H2O content on the carbonation of forsterite in supercritical CO2 (scCO(2)) at 80 degrees C and 76 bars (7.6 MPa) was investigated by a combination of NMR, XRD, TEM and XPS. When trace amounts of H2O were included, limited reaction was observed. Below H2O saturation in scCO2, reaction products were a mixture of partially hydrated/hydroxylated magnesium carbonates and hydroxylated silica species that were mainly in an amorphous state, forming a non-resolved layer on the forsterite surface. At H2O content above saturation, where forsterite was in contact with both a CO2-saturated aqueous fluid and H2O-saturated scCO(2), solid reaction products were magnesite (MgCO3) and an amorphous polymerized SiO2. Formation of these anhydrous phases implies H2O initially bound in precursor hydrated/hydroxylated reaction products was liberated, inducing further reaction. Hence, for a given fluid/mineral ratio there is a H2O threshold above which a significant portion of the H2O serves in a catalytic role where more extensive carbonation reaction occurs. Defining the role of H2O, even in low H2O content environments, is therefore critical to determining the long term impact of CO2 reactivity in the subsurface. (C) 2011 Elsevier Ltd. All rights reservedclose383

Coupled dissolution and precipitation at mineral-fluid interfaces

Reactions occurring at mineral–fluid interfaces are important in all geochemical processes and essential for the cycling of elements within the Earth. Understanding the mechanism of the transformation of one solid phase to another and the role of fluids is fundamental to many natural and industrial processes. Problems such as the interaction of minerals with CO2-saturated water, the durability of nuclear waste materials, the remediation of polluted water, and mineral reactions that can destroy our stone-based cultural heritage, are related by the common feature that a mineral assemblage in contact with a fluid may be replaced by a more stable assemblag