The interaction of myosin subfragment 1 (S1) with actin-tropomyosin-troponin (regulated actin) is highly nucleotide dependent. The binding of S1 or S1-ADP (but not S1-ATP nor N,N'-rho-phenylenedimaleimide-modified S1-ATP) to regulated actin activates ATP hydrolysis even in the absence of Ca(2+). Investigations with S1 and S1-ADP have led to the idea that some actin sites are directly blocked to...

The S1 subshell of the Loop I supernova remnant is consistent with observations of interstellar material close to the Sun. The magnetic field direction of the S1 shell at the Sun agrees with the field direction found from starlight polarization for stars that sample the ecliptic plane at the heliosphere nose, but is barely consistent with the field direction implied by the the offset angle betw...

The interaction of heavy-chain isoforms of myosin subfragment-1 with actin was examined by cross-linking with carbodiimide (EDC). The heavy chain of S1 could be cross-linked to a single actin molecule through sites on either 20 or 50 kDa proteolytic domains, resulting in complexes which migrated in an 8% polyacrylamide gel in the presence of Tricine buffer with an apparent molecular mass (M(app...

The coronavirus spike (S) protein mediates infection of receptor-expressing host cells and is a critical target for antiviral neutralizing antibodies. Angiotensin-converting enzyme 2 (ACE2) is a functional receptor for the coronavirus (severe acute respiratory syndrome (SARS)-CoV) that causes SARS. Here we demonstrate that a 193-amino acid fragment of the S protein (residues 318-510) bound ACE2...

Electronic structure calculations and nonadiabatic dynamics simulations (more than 2000 trajectories) are used to explore the Z-E photoisomerization mechanism and excited-state decay dynamics of two arylazopyrazole photoswitches. Two chiral S1 /S0 conical intersections with associated enantiomeric S1 relaxation paths that are barrierless and efficient (timescale of ca. 50 fs) were found. For th...

The mechanism of binding of myosin subfragment-1 (S1) to actin in the absence of nucleotides was studied by a combination of stopped-flow fluorescence and ms time resolution electron microscopy. The fluorescence data were obtained by using pyrene-labeled actin and exhibit a lag phase. This demonstrates the presence of a transient intermediate after the collision complex and before the formation...

Background: Recent international recommendations for the diagnosis of gestational diabetes (GD) were implemented in a university hospital. The aim was to audit the appropriateness of use of the new diagnostic approach. Methods: The same 5-month period, one before [2009, traditional two-step oral glucose tolerance test (OGTT) approach, S1] and one after the implementation of new criteria (2010, ...

To assess interleukin (IL)-4 effects on calcium signaling, bovine airway smooth-muscle (ASM) cells were loaded with fura-2 and cytosolic calcium ([Ca(2+)](i)) was measured in single cells by digital microscopy. Human recombinant IL-4 (50 ng/ml) caused small increases in [Ca(2+)](i). For single cells, carbachol-stimulated calcium transients were compared before (S1) and after (S2) exposure to IL...

BACKGROUND Recent international recommendations for the diagnosis of gestational diabetes (GD) were implemented in a university hospital. The aim was to audit the appropriateness of use of the new diagnostic approach. METHODS The same 5-month period, one before [2009, traditional two-step oral glucose tolerance test (OGTT) approach, S1] and one after the implementation of new criteria (2010, ...