Search results for "CARBONATE"

In vitro study of human alveolar macrophage and peripheral blood mononuclear cell reactive oxygen-intermediates release induced by sulfur dioxide at …

1994

Sulfur dioxide (SO2) is a major air pollutant in urban areas. Alveolar macrophages (AM) located on the alveolar surface are in direct contact with this inhaled gas. We evaluated the dose-dependent effect of SO2 exposure on the oxidative metabolism of AM and peripheral blood mononuclear cells (PBMNC) by measuring the spontaneous and stimulated reactive oxygen intermediates (ROI) release. AM or PBMNC were placed on a polycarbonate membrane, which was in direct contact with the surface of a nutrient reservoir. For exposure of the cells to SO2 a special chamber was employed, in which humidified standard air with 5% CO2 at 37 degrees C was mixed with SO2 at the desired concentration. Periods of …

Dietary Habits in a Child Population in Relation to Caries Experience

2008

Sugar consumption in Spain has remained constant at around 80 g/day since the 1970s. Although intake as sugar has fallen considerably, to around 13.5 g/person/day, the intake in processed foods has risen. Meanwhile, caries prevalence is falling or stabilizing. This situation is common in developed countries, where the impact of diet on caries has altered, probably through greater use of fluoridated products. In the Valencia region, children habitually eat sugary foods and drinks and snacks that contain starches or sugars and starches. The present study analyzed the association between caries experience, quantified as the sum of the dfs and DMFS indices, and the consumption of cariogenic foo…

Effects of 12-Week Low or Moderate Dietary Acid Intake on Acid–Base Status and Kidney Function at Rest and during Submaximal Cycling

2018

Prolonged effects of dietary acid intake on acid–base status and kidney function have not yet been studied in an intervention study in healthy subjects. Dietary acid load can be estimated by calculating the potential renal acid load (PRAL) of foods. Effects of low-PRAL and moderate-PRAL diets on acid–base status and kidney function were investigated during a 12-week exercise training period. Healthy, 20–50-year-old men (n = 21) and women (n = 25) participated in the study and were randomly divided into low-PRAL and moderate-PRAL groups. Before (PRE), mid-phase (MID) and after the intervention (POST), the subjects participated in measurement sessions, where a 12-h urine sample and fasting bl…

Combined creatine and sodium bicarbonate supplementation enhances interval swimming.

2004

This study examined the effect of simultaneous supplementation of creatine and sodium bicarbonate on consecutive maximal swims. Sixteen competitive male and female swimmers completed, in a randomized order, 2 different treatments (placebo and a combination of creatine and sodium bicarbonate) with 30 days of washout period between treatments in a double-blind crossover procedure. Both treatments consisted of placebo or creatine supplementation (20 g per day) in 6 days. In the morning of the seventh day, there was placebo or sodium bicarbonate supplementation (0.3 g per kg body weight) during 2 hours before a warm-up for 2 maximal 100-m freestyle swims that were performed with a passive recov…

Healthy and unhealthy eating at lower secondary school in Norway

2010

Aims: To assess adolescents’ eating/drinking habits of a selection of healthy and unhealthy food items at school, variations in gender and socioeconomic status in these eating habits, and variations between the schools. Methods: A cross-sectional study among 2870 adolescents (mean age: 15.5 years) within the Fruits and Vegetables Make the Marks (FVMM) project. A survey questionnaire was completed by the pupils in the classroom in the presence of a trained project worker. One school lesson (45 minutes) was used to complete the questionnaire. A total of two healthy (fruit and vegetables (FV), water) and five unhealthy (candy and/or potato chips, sweet bakery, instant noodles, regular soft dr…

The importance of potassium citrate and potassium bicarbonate in the treatment of uric acid renal stones

2017

Uric acid calculi can also be treated without surgery, with simple medical lytic therapy. After appropriate dietary adjustments and add of mineral water, the needed amount of alkali supplementation can increase pH values of the urine in order to dissolve the stones. Treatment should be prolonged to prevent stone recurrence. A case of bilateral renal uric acid stones that were successfully treated by alakalizing treatment was presented.

Enzyme-based biosilica and biocalcite: biomaterials for the future in regenerative medicine

2013

The oldest animals on Earth, sponges, form both the calcareous and the siliceous matrices of their spicules enzymatically. Until recently, it has been neglected that enzymes play crucial roles during formation of these biominerals. This paradigm shift occurred after the discovery that the enzyme silicatein, which catalyzes the polycondensation of silica, and the enzyme carbonic anhydrase (CA), which catalyzes the formation of bicarbonate (HCO3(-)/CaCO3), produce solid amorphous bioglass or biocalcite. This suggests that in mammals, biosilica and biocalcite can act anabolically during hydroxyapatite (HA) synthesis and bone formation. Biosilica and biocalcite are thus promising candidates for…

The marble field of Custonaci (Sicily-Italy)

2008

Identification of carbonate-rich outcrops on Mars by the Spirit rover.

2010

Ancient Carbonate Minerals on Mars The historical presence of liquid water on Mars together with a CO 2 -rich atmosphere should have resulted in the accumulation of large deposits of carbonate minerals. Yet, evidence for the presence of carbonates on the surface of Mars has been scarce. Using data collected by the Mars Exploration Rover, Spirit, Morris et al. (p. 421 , published online 3 June; see the Perspective by Harvey ) now present evidence for carbonate-rich outcrops in the Comanche outcrops within the Gusev crater. The carbonate is a major outcrop component and may have formed in the Noachian era (∼4 billion years ago) by precipitation from hydrothermal solutions that passed through …

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…