Cranial Suture Regeneration Mitigates Skull and Neurocognitive Defects in Craniosynostosis

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Noncanonical Transforming Growth Factor β (TGFβ) Signaling in Cranial Neural Crest Cells Causes Tongue Muscle Developmental Defects

Microglossia is a congenital birth defect in humans and adversely impacts quality of life. In vertebrates, tongue muscle derives from the cranial mesoderm, whereas tendons and connective tissues in the craniofacial region originate from cranial neural crest (CNC) cells. Loss of transforming growth factor β (TGFβ) type II receptor in CNC cells in mice (Tgfbr2^fl/fl;Wnt1-Cre) causes microglossia due to a failure of cell-cell communication between cranial mesoderm and CNC cells during tongue development. However, it is still unclear how TGFβ signaling in CNC cells regulates the fate of mesoderm-derived myoblasts during tongue development. Here we show that activation of the cytoplasmic and nuclear tyrosine kinase 1 (ABL1) cascade in Tgfbr2^fl/fl;Wnt1-Cre mice results in a failure of CNC-derived cell differentiation followed by a disruption of TGFβ-mediated induction of growth factors and reduction of myogenic cell proliferation and differentiation activities. Among the affected growth factors, the addition of fibroblast growth factor 4 (FGF4) and neutralizing antibody for follistatin (FST; an antagonist of bone morphogenetic protein (BMP)) could most efficiently restore cell proliferation, differentiation, and organization of muscle cells in the tongue of Tgfbr2^fl/fl;Wnt1-Cre mice. Thus, our data indicate that CNC-derived fibroblasts regulate the fate of mesoderm-derived myoblasts through TGFβ-mediated regulation of FGF and BMP signaling during tongue development.     

Analysis of palm dermatoglyphics in Taiwan indigenous populations

An analysis of a-b and a-d palm ridge counts was made from samples of people in eight indigenous Taiwan populations. Differences between hands, sexes, and populations were all significant. Bimanual differences for both counts were large, and right hand counts were consistently smaller than those for the left hand in all the populations. This is believed to be a consequence of the evolution of development, reflecting some inborn bilateral differences in function and anatomy. Sex differences, although small, were noticed. Variations between populations, ranging from approximately 7 to 19% of the total, were assumed to be genetic. The population relationships, based on dermatoglyphics, partially resembled those based on anthropometric measurements; and some aspects of their evolutionary significance were discussed.     

Iron modulates the activity of monoamine oxidase B in SH-SY5Y cells

Both monoamine oxidase B (MAO-B) and iron accumulation are associated with neurologic diseases including Parkinson’s disease. However, the association of iron with MAO-B activity was poorly understood. Here we took advantage of highly sensitive and specific fluorescence probes to examine the change in MAO-B activity in human dopaminergic neuroblastoma (SH-SY5Y) cells upon iron exposure. Both ferric and ferrous ions could significantly enhance the activity of MAO-B, instead of MAO-A, in SH-SY5Y cells. In addition, iron-induced increase in MAO-B probe fluorescence could be prevented by pargyline and other newly developed MAO-B inhibitors, suggesting that it was MAO-B activity-dependent. These findings may suggest MAO-B is an important sensor in iron-stressed neuronal cells.     

Glucose biosensor based on electrodeposited platinum nanoparticles and three-dimensional porous chitosan membranes

The chitosan with three-dimensional porous structure greatly increased the effective electrode surface for loading of platinum nanoparticles and promoted efficient electron transfer. The resulting biosensor had a response time (within 5 s) and a linear response from 6 μM to 4.2 mM glucose with a detection limit of 2 μM (S/N = 3). Moreover, the methodology can be applied for the immobilization of other enzymes.     

The neurotoxicity of iron,copper and cobalt in Parkinson’s disease through ROS-mediated mechanisms

Parkinson’s disease (PD) is the second most common neurodegenerative disease with gradual loss of dopaminergic neurons. Despite extensive research in the past decades, the etiology of PD remains elusive. Nevertheless, multiple lines of evidence suggest that oxidative stress is one of the common causes in the pathogenesis of PD. It has also been suggested that heavy metal-associated oxidative stress may be implicated in the etiology and pathogenesis of PD. Here we review the roles of redox metals, including iron, copper and cobalt, in PD. Iron is a highly reactive element and deregulation of iron homeostasis is accompanied by concomitant oxidation processes in PD. Copper is a key metal in cell division process, and it has been shown to have an important role in neurodegenerative diseases such as PD. Cobalt induces the generation of reactive oxygen species (ROS) and DNA damage in brain tissues.     

Chemical Constituents from a Mangrove-Derived Actinobacteria Isoptericola chiayiensis BCRC 16888 and Evaluation of Their Anti-NO Activity

Cultivation of the actinobacteria strain Isoptericola chiayiensis, a mangrove - derived actinobacteria that was isolated from a mangrove soil collected in Chiayi County, resulted in the isolation of one new 2-furanone derivative, isopterfuranone ( 1 ), one new sesquiterpenoid, isopterchiayione ( 2 ), one new benzenoid derivative, isopterinoid ( 3 ), five new flavonoids, chiayiflavans A−E ( 4 – 8 ), and 4 metabolites isolated for the first time from nature source, methyl 3-(4-methyl-2,5-dioxopyrrolidin-3-yl)propanoate ( 9 ), 3-ethyl-4-methylpyrrolidine-2,5-dione ( 10 ), chiayiensol ( 11 ) and chiayiensic acid ( 12 ). Their structures were determined through in-depth spectroscopic and mass-spectrometric analyses. Most of the isolates showed potent inhibitory effects on NO production in LPS-stimulated RAW 264.7 murine macrophages cells with IC₅₀ values ranging from 9.36 to 40.02 μM. Of these isolates, 4 and 5 showed NO inhibitory activity with IC₅₀ values of 17.14 and 9.36 μM, stronger than the positive control quercetin (IC₅₀=36.95 μM). This is the first report on flavan metabolites from the genus Isoptericola.