Super-resolution imaging and estimation of protein copy numbers at single synapses with DNA-PAINT

In the brain, the strength of each individual synapse is defined by the complement of proteins present or the "local proteome." Activity-dependent changes in synaptic strength are the result of changes in this local proteome and posttranslational protein modifications. Although most synaptic proteins have been identified, we still know little about protein copy numbers in individual synapses and variations between synapses. We use DNA-point accumulation for imaging in nanoscale topography as a single-molecule super-resolution imaging technique to visualize and quantify protein copy numbers in single synapses. The imaging technique provides near-molecular spatial resolution, is unaffected by photobleaching, enables imaging of large field of views, and provides quantitative molecular information. We demonstrate these benefits by accessing copy numbers of surface AMPA-type receptors at single synapses of rat hippocampal neurons along dendritic segments

Microcystic Cerebral Neoplasm in a Nilgai Antelope (Boselaphus tragocamelus): Putative Microcystic Meningioma

Tumours of the nervous system are rare in wild and captive mammals. In this report, we describe an intracranial, solid, space-occupying lesion originating from the meninges in a Nilgai antelope (Boselaphus tragocamelus). Histologically, the tumour had a conspicuous microcystic appearance with features similar to the histological subtype of microcystic meningioma described in humans. This is the first such tumour reported in this species

Electric Field Gradients at 57Fe in ZnFe2O4 and CdFe2O4

The nuclear quadrupole coupling constants and isomer shifts of 57Fe in the spinels ZnFe2O4 and CdFe2O4 were measured using the Mössbauer effect. The signs of the quadrupole coupling constants were determined from spectra which were taken in an applied magnetic field. The sign is negative in both spinels. The isomer shifts and Fe☒O distances indicate that Fe3+ in ZnFe2O4 is somewhat more covalently bonded than in CdFe2O4. The external field gradients at the Fe3+ positions can be interpreted in terms of the ionic point‐multipole model modified by some charge transfer between oxygen and the cations. The point charge contribution to the field gradient is positive in case of ZnFe2O4 and nearly zero in case of CdFe2O4; the predominant contribution is due to the electric dipole moments of the oxygen ions and is negative. The dipole polarizability of the oxygen ion which gave the best fit is αD = 0.8 Å3αD=0.8Å3. The effect of charge transfer on the ionic field gradient is small.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70992/2/JCPSA6-55-11-5282-1.pd