Many organisms form crystals from transient amorphous precursor phases. In cases where the precursor phases were imaged, they were seen to consist of nanosphere particles. Interestingly, some mature ...biogenic crystals also have a nanosphere particle morphology, but some are characterized by crystallographic faces that are smooth at the nanometer level. There are also biogenic crystals that have both crystallographic faces and nanosphere particle morphology. This highlight presents a working hypothesis, stating that some biomineralization processes involve growth by nanosphere particle accretion, where amorphous nanoparticles are incorporated as such into growing crystals and their morphology is preserved upon crystallization. This process produces biogenic crystals with a nanosphere particle morphology. Other biomineralization processes proceed by ion-by-ion growth, and some cases of biological crystal growth involve both processes. We also identify several biomineralization processes which do not seem to fit this working hypothesis. It is our hope that this highlight will inspire studies that will shed more light on the underlying crystallization mechanisms in biology.
Abstract Since approximately 5–10% of the ~ 50,000 tuberous sclerosis complex (TSC) patients in the US are “MRI-negative,” our goal was to test the hypothesis that they nevertheless exhibit metabolic ...abnormalities. To test this, we used proton MR spectroscopy to obtain and compare gray and white matter (GM and WM) levels of the neuronal marker, N -acetylaspartate (NAA), the glial marker, myo -inositol ( m I), and its associated creatine (Cr), and choline (Cho) between two “MRI-negative” female TSC patients (ages 5 and 43 years) and their matched controls. The NAA, Cr, Cho and m I concentrations, 9.8, 6.3, 1.4, and 5.7 mM, in the pediatric control were similar to those of the patients, whereas the adult patient revealed a 17% WM NAA decrease and 16% WM Cho increase from their published means for healthy adults — both outside their respective 90% prediction intervals. These findings suggest that longer disease duration and/or TSC2 gene mutation may cause axonal dysfunction and demyelination.
Since approximately 5a10% of the similar to 50,000 tuberous sclerosis complex (TSC) patients in the US are aMRI-negative,a our goal was to test the hypothesis that they nevertheless exhibit metabolic ...abnormalities. To test this, we used proton MR spectroscopy to obtain and compare gray and white matter (GM and WM) levels of the neuronal marker, N-acetylaspartate (NAA), the glial marker, myo-inositol (mI), and its associated creatine (Cr), and choline (Cho) between two aMRI-negativea female TSC patients (ages 5 and 43 years) and their matched controls. The NAA, Cr, Cho and mI concentrations, 9.8, 6.3, 1.4, and 5.7 mM, in the pediatric control were similar to those of the patients, whereas the adult patient revealed a 17% WM NAA decrease and 16% WM Cho increase from their published means for healthy adults a both outside their respective 90% prediction intervals. These findings suggest that longer disease duration and/or TSC2 gene mutation may cause axonal dysfunction and demyelination.
Cerebrovascular amyloidosis is caused by amyloid accumulation in walls of blood vessel walls leading to hemorrhagic stroke and cognitive impairment. Transforming growth factor-β1 (TGF-β1) expression ...levels correlate with the degree of cerebrovascular amyloid deposition in Alzheimer s disease (AD) and TGF-β1 immunoreactivity in such cases is increased along the cerebral blood vessels. Here we show that a nasally administered proteosome-based adjuvant activates macrophages and decreases vascular amyloid in TGF-β1 mice. Animals were nasally treated with a proteosome-based adjuvant on a weekly basis for three months beginning at age 13 months. Using MRI we found that while control animals showed a significant cerebrovascular pathology, proteosome-based adjuvant prevents further brain damage and prevents pathological changes in the blood-brain barrier. Using an object recognition test and Y-maze, we found significant improvement in cognition in the treated group. Our findings support the potential use of a macrophage immuno-modulator as a novel approach to reduce cerebrovascular amyloid, prevent microhemorrhage and improve cognition.
Das hässliche Entlein wird zum Schwan: Viele Organismen bilden ihre kristalline Mineralphase durch Sekundärnukleation sphärischer amorpher Nanoteilchen. Stabile amorphe Calciumcarbonat‐Biomineralien ...wurden verwendet, um eine ähnliche Umwandlung in vitro auszulösen. Die amorphen Nanosphären gingen eine Festphasenumwandlung zu hoch geordneten Calcitkristallen aus aggregierten Partikeln ein (siehe SEM‐Bild).
During the ongoing excavations of Area Q at Tel Megiddo, a variety of on-site geoarchaeological analytical methods have been used in the study of Iron Age occupations dating to the Iron Age IIA. The ...aim of this approach is to optimally combine macroarchaeology with microarchaeology in order to reconstruct activities that were carried out within an Iron Age urban neighborhood. The macroscopic finds indicate that this area belonged to a quarter that features both domestic and public structures. Of particular interest are (a) evidence for abandonment and spatial differentiation of activities in Level Q-5 associated with a large, well-built structure with 18 pillars; and (b) localized small-scale destruction associated with ephemeral metalworking activity related to occupation during Level Q-4. Similar approaches have been carried out at other sites in Israel (e.g., Tel Dor and Tell eṣ-Ṣâfi/Gath), yet only at Megiddo have we been able to use these methods to study a large excavation area (ca. 200 m2). The results shed new light on the variability of human activities in public and domestic contexts in an urban environment, and contribute to understanding the uses of space and the phenomenon of destruction by fire.
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