Polyol-combinant saliva stimulants and oral health in Veterans Affairs patients—An exploratory study

An exploratory study investigated the root caries incidence in Department of Veterans Affairs patients with exposed root surfaces. For a period of six to 30 months, the subjects were systematically assigned to groups which used chewable dragées or chewing gums that contained either xylitol or sorbitol as bulk sweeteners. The mean treatment time was 1.8 years (standard deviation = 0.8). The consumption levels of both polyols was up to 8.5 g daily, used typically in five episodes during a 16-hour period. The subjects were examined every six months in connection with their standard scheduled visits at the Veterans Affairs Medical Center. The risk for a root-surface lesion in the xylitol group was only 19% of that for a surface in the sorbitol group (relative risk, 0.19; 95% confidence interval, 0.06–0.62; p <0,0065). Simultaneous study in periodontal patients showed that both polyols significantly reduced the gingival index scores, and slightly (but not significantly) reduced the plaque index scores. Collectively, both studies suggest that frequent daily consumption of chewable, saliva-stimulating products containing essentially nonfermentable or slowly fermentable dietary carbohydrate sweeteners (xylitol and sorbitol) may have an oral-health-improving effect in Department of Veterans Affairs Medical Center patients. It is necessary to evaluate if these procedures would be efficacious in larger and expanded patient cohorts.     

Debates on the concomitant use of aspirin and Angiotensin converting enzyme inhibitors: will the consensus be reached?

During last 10 years the potential interaction between aspirin and angiotensin converting enzyme inhibitors (ACEI) has received considerable attention. Retrospective analysis of randomized trials and their meta-analyses gave conflicting results concerning existence and effects of this interaction. Taking into consideration proven benefit of both aspirin and ACEI, restricting their combined use is premature. Further studies of this issue are warranted.     

Impact of intravenous loop diuretics on outcomes of patients hospitalized with acute decompensated heart failure: insights from the ADHERE registry

The optimal use of diuretics in decompensated heart failure remains uncertain. We analyzed data from the ADHERE registry to look at the impact of diuretic dosing. 62,866 patients receiving <160 mg and 19,674 patients > or =160 mg of furosemide were analyzed. The patients receiving the lower doses had a lower risk for in-hospital mortality, ICU stay, prolonged hospitalization, or adverse renal effects. These findings suggest that future studies should evaluate strategies for minimizing exposure to high doses of diuretics.     

Functional consequences of Kir2.1/Kir2.2 subunit heteromerization

Kir2 subunits form channels that underlie classical strongly inwardly rectifying potassium currents. While homomeric Kir2 channels display a number of distinct and physiologically important properties, the functional properties of heteromeric Kir2 assemblies, as well as the stoichiometries and the arrangements of Kir2 subunits in native channels, remain largely unknown. Therefore, we have implemented a concatemeric approach, whereby all four cloned Kir2 subunits were linked in tandem, in order to study the effects of Kir2.1 and Kir2.2 heteromerization on properties of the resulting channels. Kir2.2 subunits contributed stronger to single-channel conductance than Kir2.1 subunits, and channels containing two or more Kir2.2 subunits displayed conductances indistinguishable from that of a Kir2.2 homomeric channel. In contrast, single-channel kinetics was a more discriminating property. The open times were significantly shorter in Kir2.2 channels compared with Kir2.1 channels and decreased nearly proportionally to the number of Kir2.2 subunits in the heteromeric channel. Similarly, the sensitivity to block by barium also depended on the proportions of Kir2.1 to Kir2.2 subunits. Overall, the results showed that Kir2.1 and Kir2.2 subunits exert neither a dominant nor an anomalous effect on any of the properties of heteromeric channels. The data highlight opportunities and challenges of using differential properties of Kir2 channels in deciphering the subunit composition of native inwardly rectifying potassium currents.     

Measurement of immunoglobulin concentration in cell culture supernates by computer-assisted ELISA

The enzyme-linked immunosorbent assay (ELISA) is used extensively in immunologic research for obtaining quantitative estimates of immunoglobulin concentration in cell culture supernates. Through incorporation of a microcomputer for data acquisition, storage and rapid calculation of results, a substantial reduction in total assay time may be realized. Described here are a set of menu-driven programs written in Basic for the IBM-PC which provide advantages over existing software in simplicity, versatility and accuracy. Hardware requirements are minimal. These programs should encourage greater flexibility in terms of the size and complexity of experimental designs.     

Cell proliferation after flap surgery, root conditioning and fibronectin application

This study evaluated the effects of citric acid demineralization and autologous fibronectin application on cell proliferation after mucoperiosteal flap surgery. Three adult rhesus monkeys were used. After flaps were raised, the roots were surgically exposed and planed. Surfaces on the experimental sides were decalcified with citric acid, and after thorough rinsing, the inner aspect of the flaps and the roots were bathed with 1 ml of autologous plasma fibronectin in normal saline (400 micrograms m/ml) and the flaps sutured. Contralateral teeth, acting as controls, were treated only with the surgical procedure. One hour prior to sacrifice, the animals were injected with an intravenous injection of tritiated thymidine (1 microCi/gm body weight). Surgeries were staggered to produce the following time periods: 3, 7, 15, 21 and 28 days. After processing, autoradiographs were obtained for evaluation, and labeled cells were counted in five compartments at 400 x: (1) oral epithelium, (2) crevicular area, (3) supracrestal connective tissue, (4) coronal periodontal membrane and (5) coronal bone marrow. Forty tissue sections per procedure (20 slides per tooth) were counted and means obtained for the three monkeys. Differences between experimental and control values were statistically evaluated for each component, at each time interval, using pairwise t tests. Fibronectin-treated areas showed significantly increased cellular proliferation (P less than 0.01) during the first 2 weeks, affecting mainly all the supracrestal tissues. Histologically, the establishment of a well-organized fibrinous clot at 3 days was noted in these areas. Results show a faster healing after surgery with the use of citric acid and fibronectin. It was concluded that citric acid followed by fibronectin enhanced cellular proliferation.