Neuronal-glial-vascular units now have been regarded as the basic functional elements of the CNS; however, their pathophysiological changes in the neurodegenerative condition are poorly defined. Herein we addressed these issues in the hippocampus of an Alzheimer's disease mouse model which was established by ovariectomy and then followed with 8 weeks of d-galactose injection. Immunolocalization of glial fibrillary acidic protein showed that reactive astrogliosis destroyed astrocytic domain organization in the hippocampus of model mice. Electron microscopy further demonstrated microarchitectural damage of neuronal-glial units and gliovascular units in the CA1 stratum radiatum of model group. Moreover, model mice had decreased expressions of glutamate transporter 1, glutamate/aspartate transporter, glutamine synthetase and connexin 43, but an increased expression of water channel protein aquaporin-4 in the hippocampus as revealed by immunohistochemistry and immunoblotting analysis. These results highlight that disruptions in structural integrity of the neuronal-glial-vascular units and associated functions including glutamate clearance, water transport and astrocyte syncytium contribute to the neurodegeneration induced by long-term ovarian hormone deprivation and systemic d-galactose exposure.
An RF transceiver for operation near 24 GHz with an onchip antenna, fractional-N synthesizer and other RF and analog baseband circuits is demonstrated in 130-nm CMOS. A 5-m wireless link was demonstrated using a transceiver pair. A technique for wireless calibration of an on-chip frequency reference is also demonstrated.
Influenza viruses gain entry into host cells by binding to cellular receptors and promoting the fusion of the viral envelope with the host cell membrane. The fusion peptide of influenza hemagglutinin (HA) is crucial for fusion. To examine the structural and functional roles of amino acids E11 and G8 of the H5 HA fusion peptide, a series of fusion mutants was generated. We determined the effect of each mutation on fusion activity and infection of rescued recombinant virus by polykaryon formation, cell-cell fusion assay, HA pseudovirus transduction and reverse genetics. Our findings indicate that E11V and E11A mutants dramatically inhibit fusion and that at position 11 a polar residue such as glutamic acid or serine may be desirable for preserving the fusion activity. More interestingly, one mutation (G8E) raised the threshold pH of polykaryon formation. Our results suggest that G8 as well as E11 play an important functional and structural role in membrane fusion and that the polarity of E11 is crucial for fusion activity. Finally, we developed an assay based on a reporter gene plus pseudotyped virus that could sensitively detect fusion activity.
Research is underway to explore the feasibility of implementing complete RF subsystems in standard mainstream CMOS processes without a need for any off-chip components. Progress to date has verified that RF circuits and on-chip antennas adequate for chip to chip communication can be realized, and it can be stated with some certainty that feasibility has been established. Radio architecture, signaling methodology, and individual circuit blocks have been devised and confirmed. It remains to demonstrate an on-chip reference with +/-150 ppm stability, optimize the individual circuit blocks, and demonstrate the overall concept in a single integrated chip
The feasibility of integrating antennas and required circuits to form wireless interconnects in foundry digital CMOS technologies has been demonstrated. The key challenges including the effects of metal structures associated with integrated circuits, heat removal, packaging, and interaction of transmitted and received signals with nearby circuits appear to be manageable. This technology can potentially be used for intra and inter-chip interconnection, and implementation of true single chip radios, beacons, radars, RFID tags and others, as well as contact-less high frequency testing
Highly crystalline LaCoO3 perovskite particles were prepared by a novel microwave-assisted process with a La–Co citrate complex precursor in the host pores of mesoporous SBA-15 silica. The resulting material exhibited considerably higher catalytic activity in the complete methane oxidation than a LaCoO3/SBA-15 sample prepared by a conventional method with a bulk LaCoO3 perovskite. This suggests that a higher density of lattice defects achieved on the high-surface-area LaCoO3 nanocrystals synthesized by microwave processing is essential for the superior performance of the catalyst.
Significant and suggestive linkage for BMI on 3q27 has been reported by several groups, including our own study in African Americans. To further establish the linkage evidence on 3q27, we recruited an independent African-American sample comprising 545 individuals in 128 families. We genotyped 15 short tandem-repeat markers evenly spaced in the 112 cM region around the peak on 3q27 identified in our earlier study. Multipoint linkage analysis by GENEHUNTER2 gave the maximum logarithm of odds (LOD) score 2.4 at map position 188 cM in this sample. When we combined the two samples, linkage evidence was increased to a maximum LOD score (MLS) of 4.3 (point-wise P = 4.34 x 10(-6)) at 188 cM, with a 7 cM 1-LOD-drop interval around the peak. The multiple replications of linkage evidence in the region on 3q27 strongly confirm its potential importance as a candidate region in the search for obesity-related genes.