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Background: Hippocampal neurons in the brain polarize to form multiple dendrites and one long axon. The formation of central synapses remains poorly understood. Although several of the intracellular proteins involved in the clustering of central neurotransmitter receptors and ion channels have been identified, the signals involved in pre- and postsynaptic differentiation remain elusive. Synaptotagmin1 is an abundant and important presynaptic vesicle protein that binds Ca(2+) (J Biol Chem 277:7629-7632, 2002) in regulation of synaptic vesicle exocytosis at the synapse. Synapse consists of the formation of synaptic connections and requires precise coordination of Synaptotagmin1. It was reported Synaptotagmin1 plays an important roles in the formation of axonal filopodia and branches in chicken forebrain neurons (Dev Neurobiol 73:27-44, 2013). To determine if Synaptotagmin1 could have a role in formation of axon in hippocampal neurons, we investigated the effects of Synaptotagmin1 overexpression and knockdown using the shRNA on the growth and branching of the axons of primary hippocampal neurons. We showed that overexpression of Synaptotagmin1 leads to abnormal multiple axon formation in cultured rat hippocampal neurons. Results: We first examined the effects of Synaptotagmin1 on the numbers of axon and dendrites. We found that the overexpression of Synaptotagmin1 led to the formation of multiple axons and induced an increase in the number of endogenous postsynaptic protein Homer1c clusters in cultured hippocampal neurons. Endogenous initial segment of axon was detected with anti-sodium channel (anti-NaCh) antibody and with anti-Tau1 (J Neurosci 24: 4605-4613, 2004). The endogenous initial segment of axon was stained with anti-NaCh antibodies and with anti-Tau1 antibodies. Then the numbers of prominence dyed positive were counted as axon. We attempted to specifically knockdown the endogenous Synaptotagmin1 with small hairpin RNAs (shRNAs). To further dissect the functions of endogenous Synaptotagmin1 in neuronal polarity, we used the shRNA of Synaptotagmin1 that specifically blocks the existence of endogenous Synaptotagmin1. When the shRNA of Synaptotagmin1 was introduced to the cells, the number of axons and dendrites did not change. Conclusions: These results indicate that the accumulation of Synaptotagmin1 may play an important role in axon/dendrite differentiation. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of recombinant human-soluble thrombomodulin (rTM) on lipopolysaccharide (LPS)-induced, platelet-dependent neutrophil extracellular trap (NET) formation (NETosis). Human peripheral blood neutrophils and platelets were co-incubated with or without LPS (0.2 μg/ml) in the presence and absence of rTM (2 μg/ml). NETosis was confirmed by immunostaining and confocal microscopy. In the absence of platelets, LPS did not induce NETosis in the neutrophils. NETosis, however, was induced by LPS when neutrophils were co-cultured with platelets (64 % of neutrophils). Notably, rTM was able to fully inhibit NETosis in neutrophils cultured with platelets and in the presence of LPS. rTM did not induce NETosis in this co-culture system (p < 0.01 versus LPS in the absence of rTM). These results show that rTM can suppress LPS-induced platelet-dependent NETosis in vitro.

Background: To compare the quality of the ultra-widefield images acquired by Optos® 200Tx to those acquired by Optos® California.Methods: Images of the posterior surface of a Gullstrand's model eye obtained by Optos® 200Tx were compared to those obtained by Optos® California in terms of the angular field of view and the symmetry of the image, i.e., vertical and horizontal aspect ratios at the center (0°) and at the periphery (40° and 80°) in each direction. In addition, we compared the enlargement of the image on the posterior surface as the square ratio, and the differences in the contrasts.Results: No significant differences were detected in the angular field of view between the two instruments. The aspect ratios showed that the Optos® California had more symmetrical images than the Optos® 200Tx at the center (0.98 vs 0.89, P < 0.01) and at the 40° periphery (0.93-1.04, △0.11 vs 0.79-1.01, △0.22) and 80° periphery (0.81-1.25, △0.44 vs 0.42-1.12, △0.70) in each direction. The amplitude of the square ratio of the Optos® California was smaller at 40° periphery (1.16-1.28, △0.12 vs 1.06-1.37, △0.31) and 80° periphery (2.12-2.46, △0.34 vs 1.14-3.29, △2.15). The contrast of the Optos® California images was significantly higher in the posterior pole (0.09 vs 0.12, P < 0.01), upper (0.07 vs 0.03, P < 0.01), and right (0.12 vs 0.07, P < 0.01) peripheries.Conclusion: Optos® California can record equal angular widefield images to Optos® 200Tx and more symmetrical images with higher contrast in the posterior pole, upper and right peripheries. [ABSTRACT FROM AUTHOR]