Electrogenerated microscale bubbles that are confined at the electrode surface have already been extensively studied because of their significant influence on electrochemistry. In contrast, as far as we know, whether nanoscale bubbles exist on the electrode surface has not been experimentally confirmed yet. Here, we report the observation of electrochemically controlled formation and growth of hydrogen nanobubbles on bare highly oriented pyrolytic graphite (HOPG) surface via in-situ tapping mode atomic force microscopy (TMAFM). By using TMAFM imaging, we observed that electrochemically generated hydrogen gas led to the formation of nanobubbles at the HOPG surface. We then employed a combination of techniques, including phase imaging, ex-situ degassing, and tip perturbation, to confirm the gas origin of such observed nanobubbles. We further demonstrated that the formation and growth of nanobubbles could be well controlled by tuning either the applied voltage or the reaction time. Remarkably, we could also monitor the evolution process of nanobubbles, that is, formation, growth, coalescence, as well as the eventual release of merged microbubbles from the HOPG surface.

Ocular mal-development results in heterogeneous and frequently visually disabling phenotypes that include coloboma and microphthalmia. Due to the contribution of bone morphogenetic proteins to such processes, the function of the paralogue Growth Differentiation Factor 3 was investigated. Multiple mis-sense variants were identified in patients with ocular and/or skeletal (Klippel-Feil) anomalies including one individual with heterozygous alterations in GDF3 and GDF6. These variants were characterized, individually and in combination, through integrated biochemical and zebrafish model organism analyses, demonstrating appreciable effects with western blot analyses, luciferase based reporter assays and antisense morpholino inhibition. Notably, inhibition of the zebrafish co-orthologue of GDF3 accurately recapitulates patient phenotypes. By demonstrating the pleiotropic effects of GDF3 mutation, these results extend the contribution of perturbed BMP signaling to human disease and potentially implicate multi-allelic inheritance of BMP variants in developmental disorders.

Proteins of the bone morphogenetic protein (BMP) family are known to have a role in ocular and skeletal development; however, because of their widespread expression and functional redundancy, less progress has been made identifying the roles of individual BMPs in human disease. We identified seven heterozygous mutations in growth differentiation factor 6 (GDF6), a member of the BMP family, in patients with both ocular and vertebral anomalies, characterized their effects with a SOX9-reporter assay and western analysis, and demonstrated comparable phenotypes in model organisms with reduced Gdf6 function. We observed a spectrum of ocular and skeletal anomalies in morphant zebrafish, the latter encompassing defective tail formation and altered expression of somite markers noggin1 and noggin2. Gdf6(+/-) mice exhibited variable ocular phenotypes compatible with phenotypes observed in patients and zebrafish. Key differences evident between patients and animal models included pleiotropic effects, variable expressivity and incomplete penetrance. These data establish the important role of this determinant in ocular and vertebral development, demonstrate the complex genetic inheritance of these phenotypes, and further understanding of BMP function and its contributions to human disease.

The Arabidopsis GIGANTEA (GI) gene has been shown to regulate several developmental processes, including photoperiod-mediated flowering, phytochrome B signaling, circadian clock, and carbohydrate metabolism. However, little is known about the role of GI gene in mediating the cold stress response. Here, we show that GI gene is involved in mediating the cold stress response. GI gene was induced by cold stress, but not by salt, mannitol, and abscisic acid. Moreover, gi-3 plants showed an increased sensitivity to freezing stress. However, no significant differences were detected in the transcript levels of CBF genes CBF1, CBF2, and CBF3 as well as their targeted genes RD29A, COR15A, KIN1, and KIN2 between wild-type and gi-3 plants in response to cold stress. These results suggest that GI gene positively regulates freezing tolerance via a CBF-independent pathway. In addition, intermittent cold treatments had a greater effect on flowering time in gi-3 plants than that in wild-type plants, suggesting that there may be a link between flowering time and cold stress response through GI in Arabidopsis.

Colobomata represent visually impairing ocular closure defects that are associated with a diverse range of developmental anomalies. Characterization of a chromosome 8q21.2-q22.1 segmental deletion in a patient with chorioretinal coloboma revealed elements of nonallelic homologous recombination and nonhomologous end joining. This genomic architecture extends the range of chromosomal rearrangements associated with human disease and indicates that a broader spectrum of human chromosomal rearrangements may use coupled homologous and nonhomologous mechanisms. We also demonstrate that the segmental deletion encompasses GDF6, encoding a member of the bone-morphogenetic protein family, and that inhibition of gdf6a in a model organism accurately recapitulates the proband's phenotype. The spectrum of disorders generated by morpholino inhibition and the more severe defects (microphthalmia and anophthalmia) observed at higher doses illustrate the key role of GDF6 in ocular development. These results underscore the value of integrated clinical and molecular investigation of patients with chromosomal anomalies.

No abstract

Background/Aims: As a vasodilatory drug used to treat angina, nicorandil has been shown to induce an infarct-limiting effect in various experimental animal models of myocardial ischemia-reperfusion (IR). There are multiple mechanisms causing the IR injury, among which, the endoplasmic reticulum (ER) stress and ER stress-initiated apoptosis are implicated to play an important role. However, whether ER stress is involved in nicorandil-induced cardioprotection is unknown. Methods: Post-ischemic functional recovery, lactate dehydrogenase (LDH) release and infarct size in perfused rat hearts subjected to global no-flow I/R were measured to analysis the effect of nicorandil and ER stress inducer of tunicamycin as well as phosphatidylinositol 3-kinase (PI3K) inhibitor of wortmannin on the I/R hearts. The I/R hearts tissue were harvested to evaluate apoptosis ratio with TUNEL assay and protein expression with western blot. Results: We showed that nicorandil ameliorated postischemic contractile recovery, as well as significantly reduced myocardial infarct size at a dose-dependent manner. Furthermore, nicorandil treatment inhibited the IR-induced apoptosis and ER stress. The beneficial effects of nicorandil were blocked by ER stress inducer, tunicamycin and specific phosphatidylinositol 3-kinase (PI3K) inhibitor, wortmannin. Concolusion: We conclude that the cardioprotection of nicorandil was at least in part mediated via inhibition of ER stress-induced apoptotic cell death through PI3K/Akt pathway.

We previously demonstrated that immunization of mice with plasmid DNAs (pDNAs) expressing the murine cytomegalovirus (MCMV) genes IE1-pp89 and M84 provided synergistic protection against sublethal viral challenge, while immunization with plasmids expressing putative virion proteins provided no or inconsistent protection. In this report, we sought to augment protection by increasing the breadth of the immune response. We identified another MCMV gene (m04 encoding gp34) that provided strong and consistent protection against viral replication in the spleen. We also found that immunization with a DNA pool containing 10 MCMV genes that individually were nonprotective elicited reproducible protection against low to intermediate doses of challenge virus. Moreover, inclusion of these plasmids into a mixture with gp34, pp89, and M84 DNAs provided even greater protection than did coimmunization with pp89 and M84. The highest level of protection was achieved by immunization of mice with the pool of 13 pDNAs, followed by formalin-inactivated MCMV (FI-MCMV). Immunization with FI-MCMV elicited neutralizing antibodies against salivary gland-derived MCMV, and of greatest importance, mice immunized with both the combined pDNA pool and FI-MCMV had undetectable levels of virus in the spleen and salivary glands after challenge. Intracellular cytokine staining of splenocytes from pDNA-and FI-MCMV-immunized mice showed that pDNA immunization elicited high levels of pp89-and M83-specific CD8 ؉ T cells, whereas both pDNA and FI-MCMV immunizations generated strong CD8؉ -T-cell responses against virion-associated antigens. Taken together, these results show that immunization with pDNA and inactivated virus provides strong antibody and cell-mediated immunity against CMV infection.