Cimetidine in patients with gastric ulcer: a multicentre controlled trial.

Forty-five adult outpatients with endoscopically confirmed gastric ulceration completed a double-blind trial of either cimetidine (1 g/day) or placebo. After six weeks 18 of the 23 patients receiving cimetidine showed complete ulcer healing compared with only six of the 22 patients receiving placebo. The cimetidine group also had fewer days with pain than the placebo group but the difference was not statistically significant. Cimetidine therefore seems to promote healing of gastric ulcers without severe side effects, although its effect on pain is less pronounced than in patients with duodenal ulcers.     

Membrane stabilizers inhibit potassium efflux from Staphylococcus aureus strain No. U2275

The effect of different categories of membrane stabilizers on K⁺ loss and growth has been characterized in a culture of Staphylococcus aureus. Chlorpromazine, thiopental and tetracaine at low concentrations produced a marked inhibition of K⁺ loss and an equivalent increase in the K⁺ contents of S. aureus. Whereas the inhibitory effect of chlorpromazine on K⁺ loss was observed at lower than bacteriostatic concentrations of the drug, thiopental had no effect on growth in the concentration range where K⁺ loss was maximally inhibited. It is concluded that the bacteriostatic action of chlorpromazine is probably not related to its membrane stabilizing effect only.     

A protease-activatable luminescent biosensor and reporter cell line for authentic SARS-CoV-2 infection

Efforts to define serological correlates of protection against COVID-19 have been hampered by the lack of a simple, scalable, standardised assay for SARS-CoV-2 infection and antibody neutralisation. Plaque assays remain the gold standard, but are impractical for high-throughput screening. In this study, we show that expression of viral proteases may be used to quantitate infected cells. Our assays exploit the cleavage of specific oligopeptide linkers, leading to the activation of cell-based optical biosensors. First, we characterise these biosensors using recombinant SARS-CoV-2 proteases. Next, we confirm their ability to detect viral protease expression during replication of authentic virus. Finally, we generate reporter cells stably expressing an optimised luciferase-based biosensor, enabling viral infection to be measured within 24 h in a 96- or 384-well plate format, including variants of concern. We have therefore developed a luminescent SARS-CoV-2 reporter cell line, and demonstrated its utility for the relative quantitation of infectious virus and titration of neutralising antibodies.     

Splenocytes cultured in low concentrations of IL-2 generate NK cell specificities toward syngenic and allogenic targets

Splenocytes cultured in the presence of 30-60 units/ml IL-2 for 5 days develop natural killer activity toward syngeneic and allogeneic tumor cell targets. The IL-2 activated splenocytes, themselves, are partially resistant, whereas concanavalin A-activated T blast cells are completely resistant to killing. Surprisingly, major histocompatibility complex (MHC)-I-negative target cells are also resistant to natural killer (NK)-cell-mediated killing. Cells resistant to killing were unable to block NK-cell-mediated killing of sensitive targets as judged from cold target cell inhibition experiments, and one type of target cells sensitive to killing did generally not cross-block killing of other killing-sensitive target cell types. Alloantigen exposure of splenocytes, i.e., one-way mixed lymphocyte cultures, partially prevents the development of NK-cell activity. Our data suggest that target structures which trigger killing activity of NK cells are determined by the phenotype of the target cell and are dependent on its MHC class I expression disregarding the haplotype of the cell.     

Surrogate markers for atherosclerotic disease

PURPOSE OF REVIEW: Novel treatment modalities for cardiovascular prevention are emerging rapidly. Since it is virtually impossible to evaluate all these new compounds in long-term trials using clinical end points, there is an urgent need for validated surrogate markers of atherosclerosis to save both time and costs. Over the last decade, the use of imaging markers has been widely introduced into drug-development strategies. Here we will discuss the most commonly used techniques. RECENT FINDINGS: Whereas both testing of endothelial function, assessed as flow-mediated dilation, and assessment of carotid intima-media thickness have been shown to predict future cardiovascular events, predominantly intima-media thickness has been used successfully as a surrogate marker in intervention studies. More recently, standardization of intravascular ultrasound has also enabled reproducible assessment of coronary atheroma volume. Multidetector computed tomography and electron-beam computed tomography have proven useful in providing quantitative information on plaque burden and coronary calcium content, respectively. Although cardiovascular magnetic resonance (CMR) is improving continuously, additional technical improvements will be mandatory before this technique can be implemented in multicenter clinical studies. SUMMARY: The imaging modalities reviewed here all provide specific information on either functionality or morphology of the vasculature. The value of carotid intima-media thickness for cardiovascular risk prediction has been studied most extensively. Whereas assessment of plaque burden using intravascular ultrasound appears to be the most direct way to quantify coronary changes, its predictive value for future cardiovascular events remains to be established. Awaiting further technical improvements, CMR is expected to provide the most valuable information for the evaluation of atherosclerosis in the near future.     

Highly syntenic regions in the genomes of soybean, <Emphasis Type="Italic">Medicago truncatula</Emphasis>, and <Emphasis Type="Italic">Arabidopsis thaliana</Emphasis>

Background  

Recent genome sequencing enables mega-base scale comparisons between related genomes. Comparisons between animals, plants, fungi, and bacteria demonstrate extensive synteny tempered by rearrangements. Within the legume plant family, glimpses of synteny have also been observed. Characterizing syntenic relationships in legumes is important in transferring knowledge from model legumes to crops that are important sources of protein, fixed nitrogen, and health-promoting compounds.     

Characterization and growth of Bacillus spp. in heat-treated cream with and without nisin

AIMS: To study the germination and growth of both inoculated and naturally occurring Bacillus strains in heat-treated cream with and without nisin. METHODS AND RESULTS: In heat-treated cream (90 degrees C for 15 min) stored at 8 degrees C, growth was dominated by naturally occurring Bacillus strains such as Bacillus pumilus and B. licheniformis. Only six of the 52 isolated strains were B. cereus/thuringiensis. All of the B. cereus strains, but none of the other strains, produced enterotoxin when tested with the TECRA and reverse passive latex agglutination kits. Bacterial growth during storage of the cream at 8 or 10 degrees C was completely inhibited by low concentrations of nisin. CONCLUSION: The high number of Bacillus strains surviving the heat treatment represent a risk for heat-treated food that contains cream. The safety of the cream, for instance in "ready-to-eat" products, can be improved by the addition of low concentrations of nisin. SIGNIFICANCE AND IMPACT OF THE STUDY: Spores of several Bacillus species may survive heat treatment of cream, but low concentration of nisin with inhibit germination and growth.