34 research outputs found
Evidence for virtual Compton scattering from the proton
In virtual Compton scattering an electron is scattered off a nucleon such that the nucleon emits a photon. We show that these events can be selected experimentally, and present the first evidence for virtual Compton scattering from the proton in data obtained at the Stanford Linear Accelerator Center. The angular and energy dependence of the data is well described by a calculation that includes the coherent sum of electron and proton radiation
Evidence for Virtual Compton Scattering from Proton
In virtual Compton scattering an electron is scattered off a nucleon such that the nucleon emits a photon. We show that these events can be selected experimentally, and present the first evidence for virtual Compton scattering from the proton in data obtained at the Stanford Linear Accelerator Center. The angular and energy dependence of the data is well described by a calculation that includes the coherent sum of electron and proton radiation
Nucleosomes in gene regulation: theoretical approaches
This work reviews current theoretical approaches of biophysics and
bioinformatics for the description of nucleosome arrangements in chromatin and
transcription factor binding to nucleosomal organized DNA. The role of
nucleosomes in gene regulation is discussed from molecular-mechanistic and
biological point of view. In addition to classical problems of this field,
actual questions of epigenetic regulation are discussed. The authors selected
for discussion what seem to be the most interesting concepts and hypotheses.
Mathematical approaches are described in a simplified language to attract
attention to the most important directions of this field
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
Recent trends in the use of radical prostatectomy in England: the epidemiology of diffusion
OBJECTIVE
To describe recent trends in the use of radical prostatectomy (RP) in England, as there is currently no consensus on the most effective treatment for localized prostate cancer, although RP is the treatment of choice among urological surgeons for men aged < 70 years.
METHODS
Routine data were assessed to establish the number of RPs performed in England in 1991–99. Age-standardized operation rates were compared by region and socio-economic group, and the geographical spread of use mapped.
RESULTS
The number of RPs performed annually increased nearly 20-fold between 1991 and 1999. Rates of surgery were greatest in the London National Health Service (NHS) regions and lowest in the Trent region. Outside London, the risk of surgery in a NHS hospital was significantly greater for men living in the least deprived areas; in London this trend was reversed.
CONCLUSION
Rapid increases in the use of RP showed marked regional variations, most likely related to access to prostate-specific antigen testing and the location of surgeons able to carry out radical surgery. By 1999, a third of procedures were still being undertaken in 'low-volume' hospitals, with implications for the quality of care and outcomes. Crucially, these developments occurred in the absence of robust information about the effectiveness of RP. Recent funding of a randomized trial of treatment options in this area is welcome, but wider questions remain about the timing of the evaluation of surgical technologies