Validation of PqsD as an anti-biofilm target in Pseudomonas aeruginosa by development of small-molecule inhibitors

2-Heptyl-4-hydroxyquinoline (HHQ) and Pseudomonas quinolone signal (PQS) are involved in the regulation of virulence factor production and biofilm formation in Pseudomonas aeruginosa. PqsD is a key enzyme in the biosynthesis of these signal molecules. Using a ligand-based approach, we have identified the first class of PqsD inhibitors. Simplification and rigidization led to fragments with high ligand efficiencies. These small molecules repress HHQ and PQS production and biofilm formation in P. aeruginosa. This validates PqsD as a target for the development of anti-infectives.

Early detection of maternal risk for preeclampsia

Preeclampsia is one of the leading causes of maternal and fetal morbidity and mortality. New molecular insights offer new possibilities of early diagnosis of elevated maternal risk. Maternal risk factors, biophysical parameters like Doppler examination of the uterine arteries and biochemical parameters allow early risk calculation. Preventive and effective therapeutic agents like acetylsalicylacid can be started in the early second trimester. This article reviews the diagnostic possibilities of early risk calculation to detect women having high risk for preeclampsia and the potential benefits for them, the offspring and health care systems. We provide risk calculation for preeclampsia as an important and sensible part of first trimester screening.

[Pulmonary diseases among returning travelers]

Respiratory tract infections are a frequent cause of travelers' health problems. Tropical diseases are relatively rare compared to common respiratory infections. Nevertheless, due to their potential gravity, they must be systematically considered. The differential diagnosis of tropical pathogens is wide. A targeted travel history taking into account specific epidemiological, geographical and behavioral risk factors helps focusing biological exams to identify the causative diagnosis. The chest radiography remains very helpful in this context; however, more specific exams, such as serologies are often necessary to reach a final diagnosis.

[Management of childhood malaria in Switzerland]

Imported malaria is a rare condition in current paediatric practice in Switzerland but should be suspected in all febrile children returning from a malaria-endemic region. Immediate treatment is essential to decrease the risk of complications and mortality. Severity criteria must always be searched for. We suggest a diagnostic strategy based on the use of microscopy and rapid antigen-detection tests. Treatment depends on the Plasmodium species and the severity of illness. For uncomplicated malaria, a drug combination that includes an artemisinin derivative should be used in priority. Atovaquone/proguanil represents an alternative. Chloroquine can be used in most cases of malaria caused by another Plasmodium species. Severe malaria must be treated intravenously with quinine and soon with artesunate.

Tunneling and Percolation Behavior in Granular Metals

The nature of the percolation process in granular metals is examined for the first time by a computer simulation of a system of metallic grains embedded in an insulating matrix. Assuming that the intergrain conduction is due to quantum mechanical tunneling it is found that a percolation-like critical behavior of the conductivity is obtained, but that a percolation universal behavior will be found only in a very special case. In contrast, the behavior of the electrical noise does not deviate substantially from the universal one. Comparison of these results with recent experimental observations suggests that in the metallic range, both transport properties are controlled by the continuous metallic network rather than by intergrain tunnelin.. We propose that the metallic network resembles the previously studied system of ‘inverted random voids’.