Human neutrophils sequester yeast cells or zymosan particles in two classes of phagocytic vacuoles: sealed and unsealed. The pH of sealed vacuoles was measured by a newly devised fluorometric procedure that used fluoresceinated zymosan particles, derived from Saccharomyces cerevisiae, as a pH probe. Five minutes after initiation of phagocytosis, sealed vacuoles were alkaline, exhibiting a pH of...

Extracellular acid can have important effects on cancer cells. Acid-sensing ion channels (ASICs), which emerged as key receptors for extracellular acidic pH, are differently expressed during various diseases and have been implicated in underlying pathogenesis. This study reports that ASIC1 and ASIC3 are mainly expressed on membrane of pancreatic cancer cells and upregulated in pancreatic cancer...

The interaction between smoking and the effect of histamine H2-antagonists on intragastric acidity was examined in a double blind double dummy placebo controlled study. Healthy volunteers, 11 smokers and 10 non-smokers, were given, on four separate days at least one week apart, either placebo or cimetidine 800 mg nocte or ranitidine 2 X 150 mg per day or ranitidine 300 mg nocte. Tablets were ta...

An article in a recent issue of this journal by Dr. A. C. Chandler on soil acidity and survival of hookworm.larvae begins as follows: " It is a prevalent opinion that acidity in soil has a tendency to shorten the life of infective hookworm larvae. Hirst (1924), for instance, says "a markedly acid reaction is also most unfavourable to the continued survival of hookworm larvae" and remarks that t...

Suppose we are using a pH meter to test acidity/alkalinity of a solution used in a manufacturing process. The pH of pure water is 7.00. For samples in the pH range from about 5 to 9 the meter gives normally distributed readings with • μ equal to the true pH of the sample and • standard deviation σ = 0.20. The meter is tested each morning to make sure it is operating properly: n = 4 samples of p...

Jellies of seven grapevine varieties were physico-chemical and sensorial characterized for the first time. Jellies differed significantly in moisture and ash contents, colour, pH, acidity and antioxidant activities. ‘Tinta Carvalha’ was the darkest and redness jelly, showing the highest antioxidant activity. Regarding sensory characteristics, no significant differences in the appearance, taste,...

Soil acidity, which is characterized by mainly aluminum (Al) toxicity and often calcium (Ca) deficiency, is a serious constraint for crop production in many regions of the world. Soil acidity is traditionally corrected by applications of lime (CaCO3 or Ca(OH)2), which raise soil pH, precipitate Al and provide Ca. However, high rates of lime cannot be afforded because of its high cost relative t...

OBJECTIVES The aim of this investigation was to give insights into the impact of carbohydrate-electrolyte drinks on the likely capacity of enamel surface dissolution and the influence of human saliva exposure as a biological protective factor. MATERIALS AND METHODS The pH, titratable acidity (TA) to pH 7.0, and buffer capacity (β) of common beverages ingested by patients under physical activi...

AIMS Somatostatin analogues (e.g. vapreotide) are used for treatment of acromegaly, endocrine tumours and variceal bleeding. The pharmacodynamic effects of vapreotide have, however, not been documented in the gastrointestinal tract. The aim of this study was to investigate the effects of continuous vapreotide administration on gastric acidity, gallbladder contraction and hormone release. METH...