Skin dryness and irritant contact dermatitis induced by the prolonged use of surgical gloves are issues faced by physicians. To address these concerns, manufacturers have introduced surgical gloves that incorporate a moisturizing component on their inner surface, resulting in documented results showing a reduction in hand dermatitis. However, the spatial distribution of moisturizers applied to surgical gloves within the integument remains unclear. Using matrix-assisted laser desorption/ionization (MALDI)–mass spectrometry imaging (MSI), we investigated the spatial distribution of moisturizers in surgical gloves within artificial membranes. Recently, dermal permeation assessments using three-dimensional models, silicone membranes, and Strat-M have gained attention as alternative approaches to animal testing. Therefore, in this study, we established an in vitro dermal permeation assessment of commercially available moisturizers in surgical gloves using artificial membranes. In this study, we offer a methodology to visualize the infiltration of moisturizers applied to surgical gloves into an artificial membrane using MALDI–MSI, while evaluating commercially available moisturizer-coated surgical gloves. Using our penetration evaluation method, we confirmed the infiltration of the moisturizers into the polyethersulfone 2 and polyolefin layers, which correspond to the epidermis and dermis of the skin, after the use of surgical gloves. The MSI-based method presented herein demonstrated the efficacy of evaluating the permeation of samples containing active ingredients.
Summary. The effects of adenine and various nucleosides on adenine nucleotide metabolism in red cells, as well as on other factors related to the storability of blood were compared during six weeks of storage under blood bank conditions. Adenosine triphosphate (ATP) and total adenine nucleotides were maintained at higher levels, and higher ratios of ATP to adenine diphosphate were observed, in blood containing citrate‐phosphate‐dextrose (CPD) solution than in blood containing acid‐citrate‐dextrose (ACD) solution. Higher levels of ATP and total adenine nucleotides were maintained in blood containing ACD together with both adenine and inosine than in blood containing ACD alone or together with only one of the two purines. ACD‐adenine was more effective in maintaining adenine nucleotides than was ACD‐inosine. Addition of uridine did not have any effect on adenine nucleotides in red cells. ATP and total adenine nucleotides were maintained at higher levels in CPD‐adenine than in CPD alone. The effect of CPD‐inosine or CPD‐adenine‐inosine was not investigated. ACD‐inosine caused a marked increase in plasma lactate, and inhibited glucose utilization, during storage. An increase in plasma inorganic phosphate was delayed by the addition of inosine, and this effect was augmented by adenine and guanosine. There were no findings suggestive of a beneficial effect of these additives on active cation transport, osmotic fragility, hemolysis, or the deterioration of blood cell morphology. Ouabain, an inhibitor of ATPase, had little effect on red cell nucleotide patterns or on other biochemical or morphological criteria for blood storage, possibly because of the low activity of ATPase at 4°C.
Summary After platelet-rich plasma was incubated with radioactive adenine, radioactive adenine nucleotides in platelets were separated by two-dimensional thin-layer chromatography. Radioactive adenine was selectively incorporated into adenine nucleotides. Gradual decomposition of labelled nucleotides was observed after longer period of incubation. Radioactive ATP, ADP, AMP, IMP, and hypoxanthine were separated from PCA extract of platelets. On the other hand, radioactive adenine and hypoxanthine were separated from platelet-poor plasma. After thrombin treatment, radioactive ATP in platelets broke down rapidly, while radioactive ADP decreased more slowly. Radioactive AMP increased at first in the cellular and supernatant fractions, and then decreased gradually. The accumulation of radioactive hypoxanthine was observed in the supernatant fraction. Released radioactive ATP and ADP were 23% and 22% of the initial radioactive ATP and ADP in platelets, respectively.
Mass spectrometry imaging (MSI) is a well-known method for the ionization of molecules on tissue sections and the visualization of their localization. Recently, different sample preparation methods and new instruments have been used for MSI, and different molecules are becoming visible. On the other hand, although several quantification methods (q-MSI) have been proposed, there is still room for the development of a simplified procedure. Here, we have attempted to develop a reproducible and reliable quantification method using a calibration curve prepared from tissue debris of a frozen section of a sample when we trim the frozen blocks. We discuss the reproducibility of this method across different sample lots and the effect of the biological matrix (ion suppression) on our results. The quantitative performance was evaluated in terms of accuracy and relative standard deviation, and the reliability of the quantitative values obtained by matrix-assisted laser desorption/ionization-MSI was further evaluated by enzyme-linked immunosorbent assay (ELISA). Our q-MSI method for the quantification of dopamine in mouse brain tissue was found to be highly linear, accurate, and precise. The quantitative values obtained by MSI were found to be highly comparable (>85% similarity) to the results obtained by ELISA from the same tissue extracts.
Summary Adenosine was rapidly incorporated into human platelets, and the inhibitory effect of adenosine on platelet aggregation was correlated with the incorporation process. Adenosine potentiated the inhibitory action of other inhibitors, such as dipyridamole, prostaglandin E1 and Y-3642. The inhibition of aggregation was associated with the preservation of platelet adenine nucleotides and the prevention of ADP release. On the other hand, the radioactive adenine nucleotide pattern of platelets was not substantially affected by inhibitors. The relation of inhibition of aggregation with ADP release was discussed.
Summary Changes in platelet adenine nucleotides during collagen-induced aggregation were estimated. Averaged values of ATP and ADP in intact platelets were 56.3 and 28.9 attomoles per platelet, respectively. After collagen-induced aggregation, intracellular ATP plus ADP was depleted to about half of that in intact platelets. The released ADP accounted for 13% of that in intact platelets. Behavior of platelet adenine nucleotides during aggregation was divided into the following phases. At first, platelet ATP decreased without the release of nucleotides. The release of ADP occurred at the stage of rapid change of light transmission. Subsequently, the released ADP decomposed in parallel with the degradation of intracellular ADP. The radioactive ATP in platelets decreased during exposure to collagen, without appreciable release of radioactive nucleotides. The ATP released from disrupted platelets was rapidly metabolized in plasma.
