Long-Range Forces of QCD

We consider the scattering of two color dipoles (e.g., heavy quarkonium states) at low energy - a QCD analog of Van der Waals interaction. Even though the couplings of the dipoles to the gluon field can be described in perturbation theory, which leads to the potential proportional to (N_c^2-1)/R^{7}, at large distances R the interaction becomes totally non-perturbative. Low-energy QCD theorems are used to evaluate the leading long-distance contribution \sim (N_f^2-1)/(11N_c - 2N_f)^2 R^{-5/2} exp(-2 \mu R) (\mu is the Goldstone boson mass), which is shown to arise from the correlated two-boson exchange. The sum rule which relates the overall strength of the interaction to the energy density of QCD vacuum is derived. Surprisingly, we find that when the size of the dipoles shrinks to zero (the heavy quark limit in the case of quarkonia), the non-perturbative part of the interaction vanishes more slowly than the perturbative part as a consequence of scale anomaly. As an application, we evaluate elastic \pi J/\psi and \pi J/\psi \to \pi \psi' cross sections.Comment: 16pages, 9 eps figures; discussion extended, 2 new references added, to appear in Phys.Rev.

Whole-genome sequencing reveals host factors underlying critical COVID-19

Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease

6 Jahre Erfahrungen mit einem Arzneimittelberatungsdienst für Patienten

BACKGROUND AND PURPOSE: Many patients are inadequately informed about their drug therapy. There is thus a need for providing additional drug information to patients. The authors here report on a 6-year experience with a drug information service for patients. PATIENTS AND METHODS: The information service was available by telephone, e-mail or regular mail and was addressed initially to patients in Saxony and since 2005 to patients throughout Germany. Demographic and drug therapy data of the patients were registered and analyzed using a relational database. All enquiries to the information service between August 2001 and January 2007 were evaluated. RESULTS: 5,587 enquiries were registered. 61.4% of the persons calling were female and 33.8% male (sex was unknown in 4.8% by anonymous calls). The most frequent reasons for an enquiry were a general need for information about drugs and therapy (27.5%) and adverse drug reactions (24.7%). The drug group most frequently enquired about were cardiovascular drugs, accounting for 34.4%, followed by neuropsychiatric drugs (15.1%). CONCLUSION: The results of this analysis show an evident need for a drug information service for patients. This need is possibly caused by the shortage of time that physicians can devote to patients. An independent and competent drug information service may improve the quality of medical care and the satisfaction of the patients involved