Humboldt University of Berlin

About: Humboldt University of Berlin is a education organization based out in Berlin, Germany. It is known for research contribution in the topics: Population & Transplantation. The organization has 33671 authors who have published 61781 publications receiving 1908102 citations. The organization is also known as: Humboldt-Universität zu Berlin & Universitas Humboldtiana Berolinensis.

Cutting Edge: Immune Cells as Sources and Targets of the IL-10 Family Members?

Abstract: This study investigated the expression of five novel human IL-10-related molecules and their receptors in blood mononuclear cells. IL-19 and IL-20 were found to be preferentially expressed in monocytes. IL-22 and IL-26 (AK155) expression was exclusively detected in T cells, especially upon type 1 polarization, and in NK cells. IL-24 (melanoma differentiation-associated gene 7) expression was restricted to monocytes and T cells. Detection of these molecules in lymphocytes was predominantly linked to cellular activation. Regarding T cells, IL-26 was primarily produced by memory cells, and its expression was independent on costimulation. In contrast to the high expression of receptors for IL-10 homologs in different tissues and cell lines, monocytes and NK, B, and T cells showed clear expression only of IL-10R1, IL-10R2, and IL-20R2. In these cells, IL-20R2 might be part of a still-unknown receptor complex. Therefore, immune cells may represent a major source but a minor target of the novel IL-10 family members.

Bi-stable neural state switches.

Abstract: Here we describe bi-stable channelrhodopsins that convert a brief pulse of light into a stable step in membrane potential. These molecularly engineered probes nevertheless retain millisecond-scale temporal precision. Photocurrents can be precisely initiated and terminated with different colors of light, but operate at vastly longer time scales than conventional channelrhodopsins as a result of modification at the C128 position that extends the lifetime of the open state. Because of their enhanced kinetic stability, these step-function tools are also effectively responsive to light at orders of magnitude lower intensity than wild-type channelrhodopsins. These molecules therefore offer important new capabilities for a broad range of in vivo applications.

Noninvasive detection of myocardial ischemia from perfusion reserve based on cardiovascular magnetic resonance

Abstract: Background—Myocardial perfusion reserve can be noninvasively assessed with cardiovascular MR. In this study, the diagnostic accuracy of this technique for the detection of significant coronary artery stenosis was evaluated. Methods and Results—In 15 patients with single-vessel coronary artery disease and 5 patients without significant coronary artery disease, the signal intensity–time curves of the first pass of a gadolinium-DTPA bolus injected through a central vein catheter were evaluated before and after dipyridamole infusion to validate the technique. A linear fit was used to determine the upslope, and a cutoff value for the differentiation between the myocardium supplied by stenotic and nonstenotic coronary arteries was defined. The diagnostic accuracy was then examined prospectively in 34 patients with coronary artery disease and was compared with coronary angiography. A significant difference in myocardial perfusion reserve between ischemic and normal myocardial segments (1.08±0.23 and 2.33±0.41; P...

Coupling of brain activity and cerebral blood flow: basis of functional neuroimaging.

Abstract: The coupling of brain cell function to the vascular system is the basis for a number of functional neuroimaging methods relevant for human studies. These include methods as diverse as functional magnetic resonance imaging, positron emission tomography, single photon emission tomography, optimal intrinsic signals, as well as near infrared spectroscopy, a method that may have imaging capabilities in the near future. These methods map a specific localized brain activation through a vascular response, such as an increase in cerebral blood flow or a change in blood oxygenation. To understand these direct maps to obtain high resolution maps of localized functional brain activity, a precise knowledge of the specific underlying physiological mechanisms and methodological properties and restrictions is essential. In this article, these fundamental physiological and methodological aspects will be discussed. After reviewing how the techniques cited obtain maps of functional activity, we will discuss our current knowledge of the physiology of coupling with particular reference to the functional imaging techniques. Specifically, we will consider the function, the mediators, and the hemodynamic mechanisms of coupling and point out potential interference by diet, and neurological disease.