Inert Group-Containing Electrolyte Additive Enabling Stable Aqueous Zinc-Ion Batteries.

Aqueous zinc ion batteries (AZIBs) are considered promising energy storage devices because of their high theoretical energy density and cost-effectiveness. However, the ongoing side reactions and zinc dendrite growth during cycling limit their practical application. Herein, trisodium methylglycine diacetate (Na3MGDA) additive containing the additional inert group methyl is introduced for Zn anode protection, and the contribution of methyl as an inert group to the Zn anode stability is discussed. Experimental results reveal that the methyl group with various effects enhances the interaction between the polar groups in Na3MGDA and the Zn2+/Zn anode. Thus, the polar carboxylate negative ions in MGDA anions can more easily modify the solvation structure and adsorb on the anode surface in situ to establish a hydrophobic electrical double layer (EDL) layer with steric hindrance effects. Such the EDL layer exhibits a robust selectivity for Zn deposition and a significant inhibition of parasitic reactions. Consequently, the Zn||Zn symmetric battery presents 2375 h at 1 mA cm-2, 1 mAh cm-2, and the Zn||V6O13 full battery provides 91% capacity retention after 1300 cycles at 3 A g-1. This study emphasizes the significant role of inert groups of the additive on the interfacial stability during the plating/stripping of high-performance AZIBs.

Prognostic value of IKBIP in papillary renal cell carcinoma.

BACKGROUND: I kappa B kinase interacting protein, a highly conserved gene, has rarely been reported in cancer. According to previous study, IKBIP has only been shown to promote malignant progression of glioma. In other malignant tumors, few reports have examined the function of IKBIP, especially in papillary renal cell carcinoma. Therefore, the molecular profiles and clinical prognostic values of the IKBIP in papillary renal cell carcinoma remain undetermined. METHODS: Several bioinformatic platforms and Immunohistochemistry were used to clarify the expression and prognostic values of IKBIP in Papillary renal cell carcinoma. RESULTS: In this study, GEPIA and TIMER platform were used to identify mRNA expression of IKBIP in papillary renal cell carcinoma. And our results revealed that IKBIP mRNA expression was up-regulated in papillary renal cell carcinoma than in its corresponding normal tissues. In addition, high mRNA expression levels of IKBIP were correlated with age, pathological stage, pathological T stage and pathological N stage. Moreover, High IKBIP mRNA expression was negatively correlated with overall survival (OS) and disease-free survival (DFS) in patients of papillary renal cell carcinoma. Besides, Multivariate analysis indicated that IKBIP mRNA expression was an independent prognostic factor for patients of papillary renal cell carcinoma. Furthermore, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed IKBIP co-expressed genes were enriched in homologous recombination, DNA replication, cell cycle, Mismatch repair, Fanconi anemia pathway, P53 signaling pathway and nucleotide excision repair. And Immunohistochemical profile showed that protein expression of IKBIP was higher in papillary renal cell carcinoma than adjacent normal tissue. CONCLUSIONS: Overall, our findings reveled that IKBIP may act as a novel and potential tumor factor to accelerate papillary renal cell carcinoma progression, meanwhile, IKBIP could serve as a promising target for treating papillary renal cell carcinoma.

Community assembly of bacteria and archaea in coastal waters governed by contrasting mechanisms: A seasonal perspective.

Marine planktonic bacteria and archaea commonly exhibit pronounced seasonal succession in community composition. But the existence of seasonality in their assembly processes and between-domain differences in underlying mechanism are largely unassessed. Using a high-coverage sampling strategy (including single sample for each station during four cruises in different seasons), 16S rRNA gene sequencing, and null models, we investigated seasonal patterns in the processes governing spatial turnover of bacteria and archaea in surface coastal waters across a sampling grid over ~300 km in the East China Sea. We found that archaea only bloomed in prokaryotic communities during autumn and winter cruises. Seasonality mostly overwhelmed spatial variability in the compositions of both domains. Bacterial and archaeal communities were dominantly governed by deterministic and stochastic assembly processes, respectively, in autumn cruise, probably due to the differences in niche breadths (bacteria < archaea) and relative abundance (bacteria > archaea). Stochasticity dominated assembly mechanisms of both domains but was driven by distinct processes in winter cruise. Determinism-dominated assembly mechanisms of bacteria rebounded in spring and summer cruises, reflecting seasonal variability in bacterial community assembly. This could be attributed to seasonal changes in bacterial niche breadths and habitat heterogeneity across the study area. There were seasonal changes in environmental factors mediating the determinism-stochasticity balance of bacterial community assembly, holding a probability of the existence of unmeasured mediators. Our results suggest contrasting assembly mechanisms of bacteria and archaea in terms of determinism-vs.-stochasticity pattern and its seasonality, highlighting the importance of seasonal perspective on microbial community assembly in marine ecosystems.

Oil body bound oleosin-rhFGF9 fusion protein expressed in safflower (Carthamus tinctorius L.) stimulates hair growth and wound healing in mice.

BACKGROUND: Fibroblast growth factor 9 (FGF9) is a heparin-binding growth factor, secreted by both mesothelial and epithelial cells, which participates in hair follicle regeneration, wound healing, and bone development. A suitable source of recombinant human FGF9 (rhFGF9) is needed for research into potential clinical applications. We present that expression of oleosin-rhFGF9 fusion protein in safflower (Carthamus tinctorius L.) seeds stimulates hair growth and wound healing. RESULTS: The oleosin-rhFGF9 expressed in safflower seeds, in which it localizes to the surface of oil bodies. The expression of oleosin-rhFGF9 was confirmed by polyacrylamide gel electrophoresis and western blotting. According to BCA and Enzyme-linked immunosorbent assay (ELISA) assay, the results show that the expression level of oleosin-rhFGF9 was 0.14% of oil body protein. The oil body bound oleosin-rhFGF9 showed mitogenic activity towards NIH3T3 cells in a methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay. The efficacy of oil body bound oleosin-rhFGF9 in promoting hair growth and wound healing was investigated in C57BL/6 mice. In a hair regeneration experiment, 50 µg/µl oil body bound oleosin-rhFGF9 was applied to the dorsal skin of mice in the resting phase of the hair growth cycle. After 15 days, thicker hair and increased number of new hairs were seen compared with controls. Furthermore, the number of new hairs was greater compared with rhFGF9-treated mice. The hair follicles of mice treated with oil body bound oleosin-rhFGF9 expressed ß-catenin more abundantly. In a wound healing experiment, dorsal skin wounds were topically treated with 50 µg/µl oil body bound oleosin-rhFGF9. Wound healing was quicker compared with mice treated with rhFGF9 and controls, especially in the earlier stages of healing. CONCLUSIONS: The oil body bound oleosin-rhFGF9 promotes both hair growth and wound healing. It appears to promote hair growth, at least in part, by up-regulating ß-catenin expression. The potential of oil body bound oleosin-rhFGF9 as an external drug can treat the alopecia and wounds or use in further clinical application.

[Expression of oleosin-rhFGF9 fusion protein in Carthamus tinctorius and determination of hair regeneration and wound repair potential in mice].

The expression of fibroblast growth factor 9 (FGF9) recombinant fusion protein in Carthamus tinctorius was used to identify its effect on hair regrowth and wound repair system in mice, providing a basis for C. tinctorius as a plant bioreactor, and establishing a foundation for commercial applications of FGF9 fusion protein in hair regrowth and wound repair. The identified pOTBar-oleosin-rhFGF9 plasmid was transformed into Agrobacterium tumefaciens EHA105 by freeze-thaw method, and the oleosin-rhFGF9 gene was transformed into safflower leaves by A. tumefaciens mediated method. Transgenic safflower seedlings were then obtained by tissue culture. After basta screening, transgenic T3 safflower seeds were obtained by grafting method, PCR verification and propagation. The expression of oleosin-rhFGF9 was detected by Western blot, and the content of oleosin-rhFGF9 fusion protein was 0.09% by using ELISA quantitative method. It was observed that 60 µg·L⁻¹ transgenic safflower oil had better effect on promoting NIH/3T3 cells proliferation in a certain dose-dependent manner. Sixty C57BL/6 mice were used to establish alopecia model and wound model respectively, and then were randomly divided into control group (treated with PBS or saline), negative group (treated with wild type safflower seed oil bodies, 60 g·L⁻¹), positive group (treated with FGF9, 0.054 g·L⁻¹), low dose group (treated with transgenic safflower oil bodies, 10 g·L⁻¹) and high dose group (treated with transgenic safflower oil bodies, 60 g·L⁻¹). The skin of all above-mentioned mice models were coated with soft adhesive manner every other day, 100 µL/time. After 15 days, the mice skin was cut and embedded for histological analysis. The hair regrowth experimental results showed that the hair of mice grew well, and the mice in high dose group had bushy hair, with significant effect on regeneration hair number as compared with the positive group. The healing was obvious in wound experiment, with significant healing effect in positive group, high dose group and low dose group as compared to blank control group. Furthermore, high dose group remarkably showed a better and higher healing effect than the positive group at day 5. Oleosin-rhFGF9 was successfully transformed into safflower, and T3 transgenic safflower oil bodies expressed oleosin-rhFGF9 fusion protein were obtained, with the role of promoting hair regeneration and wound repair in mice.

Oil Body-Bound Oleosin-rhFGF-10: A Novel Drug Delivery System that Improves Skin Penetration to Accelerate Wound Healing and Hair Growth in Mice.

Recombinant human fibroblast growth factor 10 (rhFGF-10) is frequently used to treat patients with skin injuries. It can also promote hair growth. However, the effective application of rhFGF-10 is limited because of its poor stability and transdermal absorption. In this study, polymerase chain reaction (PCR) and Southern blotting were used to identify transgenic safflowers carrying a gene encoding an oleosin-rhFGF-10 fusion protein. The size and structural integrity of oleosin-rhFGF-10 in oil bodies extracted from transgenic safflower seeds was characterized by polyacrylamide gel electrophoresis and western blotting. Oil body extracts containing oleosin-rhFGF-10 were topically applied to mouse skin. The absorption of oleosin-rhFGF-10 was studied by immunohistochemistry. Its efficiency in promoting wound healing and hair regeneration were evaluated in full thickness wounds and hair growth assays. We identified a safflower line that carried the transgene and expressed a 45 kDa oleosin-rhFGF-10 protein. Oil body-bound oleosin-rhFGF-10 was absorbed by the skin with higher efficiency and speed compared with prokaryotically-expressed rhFGF-10. Oleosin-rhFGF-10 also enhanced wound closure and promoted hair growth better than rhFGF-10. The application of oleosin-rhFGF-10 in oil bodies promoted its delivery through the skin, providing a basis for improved therapeutic effects in enhancing wound healing and hair growth.

Downregulation of quinone reductase 2 attenuates vascular smooth muscle cells proliferation and neointimal formation in balloon injured rat carotid artery.

BACKGROUND/AIMS: Quinone reductase 2 (NQO2) is a flavoprotein that catalyzes the metabolic reduction of quinines, but its biological mechanism in vascular smooth muscle cells (VSMCs) is unclear. The aim of this study was to evaluate the role of NQO2 on VSMCs proliferation and the neointimal formation in balloon injured rat carotid artery. METHODS: Left common carotid arteries from Sprague-Dawley rats were injured by a balloon catheter, and the injured arteries were incubated with 50 µL solution of NQO2-siRNA-GFP lentiviral vectors, NC-siRNA-GFP lentiviral vectors or PBS for 1 h. The rats were euthanized for morphometric and immunohistochemical analysis, real-time PCR and western blot analysis at 2 weeks after balloon injury and gene transfer. The cultured rat VSMCs transduced with NQO2-siRNA-GFP or NC-siRNA-GFP lentiviral vectors were used for cell proliferation assay, real-time PCR and western blot analysis. In order to detect the vascular or intracellular ROS level, the lentiviral vectors without GFP were used to transfect the injured common carotid arteries and the cultured rat VSMCs. RESULTS: Lentiviral vectors bearing NQO2 siRNA could reduce NQO2 protein level and suppress NQO2 mRNA expression in balloon injured artery walls and cultured rat VSMCs. Downregulation of NQO2 significantly suppressed VSMCs proliferation and intimal formation. NQO2 siRNA treatment could reduce vascular or intracellular ROS level and decrease the phosphorylation of the ERK1/2 in balloon injured artery walls and cultured rat VSMCs. CONCLUSION: Our study suggests that downregulation of NQO2 significantly suppresses VSMCs proliferation and progression of neointimal formation after vascular injury.

Long noncoding RNA CLAN promotes lymphangiogenesis in the colorectal carcinoma.

Metastasis is the main cause of colorectal cancer (CRC)-related death and lymph node plays a vital role in this process. Long noncoding RNAs (lncRNAs) are emerging as an important factor of biological progress in cancers. However, lncRNAs related to CRC metastasis was rarely reported.CLAN expression data of tumor tissues and normal tissues were obtained from GEPIA database and 23 paired tumor and normal samples of patients. CLAN expression of 85 patients was carried out with RNA extracted from FFPE samples and quantified with qRT-PCR. Patients' clinical features were collected from department of Pathology of the Affiliated Hospital of Southwest Medical University. Immunohistochemistry staining was used to detect the metastasis-related proteins.CLAN was highly expressed in tumor tissues. And the expression level was not correlated with age, gender, differentiation, and location of CRC patients. Also, CLAN expression did not correlated with budding, LVI, and TILs. However, CLAN expression was strongly associated with lymph node metastasis and higher TNM stage. CLAN changed the lymphatic vessel density by promoting lymphangiogenesis but CLAN did not affect the blood vessel density.CLAN was a unique lncRNA that promoted lymphangiogenesis to accelerate CRC metastasis. CLAN might play a unique role in tumor early dissemination through lymphatic vessel.

Negative regulation of quinone reductase 2 by resveratrol in cultured vascular smooth muscle cells.

1. Resveratrol, a polyphenol in red wine, has a cardioprotective effect. Resveratrol-targeting protein (RTP) has been purified using a resveratrol affinity column (RAC) and has been identified as quinone reductase type 2 (NQO2). We hypothesize that NQO2 is the target protein of resveratrol in vascular smooth muscle cells (VSMC) and that resveratrol inhibits proliferation of VSMC through its action on NQO2. In the present study, we investigated the correlation between NQO2 regulation and cell proliferation in VSMC in response to resveratrol treatment. 2. The RTP was purified using RAC and was detected with a NQO2 polyclonal antibody. The VSMC were incubated with resveratrol (1, 10 and 50 micromol/L) for 24, 48 and 72 h. Cell proliferation was detected by cell counting and bromodeoxyuridine (BrdU) assay. A lentiviral vector incorporating NQO2 short interference (si) RNA of short hairpin design was constructed and transduced into VSMC. Real-time quantitative polymerase chain reaction was used to measure NQO2 mRNA levels; NQO2 expression was determined by western blot analysis. 3. Using RAC, we extracted a 26 kDa protein from aortic smooth muscle, which was referred to as RTP-26. Proliferation of VSMC was inhibited by resveratrol in a concentration- and time-dependent manner. The mRNA and protein expression of NQO2 was also repressed by resveratrol in a concentration- and time-dependent manner. A similar pattern of inhibition was observed for cells treated with resveratrol (25 micromol/L) as for cells transduced with a lentiviral vector containing siRNA sequences against NQO2. 4. Collectively, these data indicate that the suppression of VSMC proliferation mediated by resveratrol correlates with NQO2 downregulation.

Interactive effect of nitrogen source and high CO2 concentration on the growth of the dinoflagellate Alexandrium tamarense and its toxicity to zebrafish (Danio rerio) embryos.

The effects and interactive effects of different nitrogen (N) sources (ammonium, nitrate, and urea) and carbon dioxide (CO2) concentrations were investigated on Alexandrium tamarense, a harmful marine dinoflagellate, by measuring its growth (µ), extracellular carbonic anhydrase (CA), and its toxicity to zebrafish (Danio rerio) embryo. The µ and CA were influenced more strongly by CO2 concentrations rather than by N sources; significant effects of CO2 on µ and CA were observed under low CO2 concentration (LC) conditions compared to high CO2 concentration (HC) conditions. The ammonium and nitrate media under LC conditions had the maximum µ and CA, which was inhibited under HC conditions. The embryotoxic effects were influenced more strongly by the N sources than by CO2 concentrations, thus excluding the lower deformation in urea under HC conditions. Moreover, the antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GPX), glutathione S-transferase (GST), and catalase (CAT) were detected in normal (untreated) zebrafish embryos, and among them, the level of SOD was the highest. In summary, this study provides a clear insight for understanding the effects and interactive effects of N sources and CO2 concentrations on the growth and toxicity of harmful dinoflagellates.

Complete mitochondrial genome of the Sharpnose stingray Himantura gerrardi (Myliobatiformes: Dasyatidae).

In this study, we presented the complete mitochondrial genome of the Sharpnose stingray Himantura gerrardi for the first time, which was 17,685 bp in length and contained 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a putative control region. The overall nucleotide composition was 30.1% A, 27.5% C, 14.5% G and 28.0% T. A total of 22 bp overlaps and 83 bp short intergenic spaces were found in the mitogenome. Two start codons (ATG and GTG) and two stop codons (TAG and TAA/T) were used in the protein-coding genes. The origin of L-strand replication (OL) sequence formed a hairpin structure between the tRNA-Asn and tRNA-Cys genes. The termination associated sequence (TAS) formed a hairpin structure near the tRNA-Pro in the control region.

Magnetic properties and heavy metal contents of automobile emission particulates.

Measurements of the magnetic properties and total contents of Cu, Cd, Pb and Fe in 30 automobile emission particulate samples indicated the presence of magnetic particles in them. The values of frequency dependent susceptibility (chi(fd)) showed the absence of superparamagnetic (SP) grains in the samples. The IRM(20 mT) (isothermal remanent magnetization at 20 mT) being linearly proportional to SIRM (saturation isothermal remanent magnetization) (R(2)=0.901), suggested that ferrimagnetic minerals were responsible for the magnetic properties of automobile emission particulates. The average contents of Cu, Cd, Pb and Fe in automobile emission particulates were 95.83, 22.14, 30.58 and 34727.31 mg/kg, respectively. Significant positive correlations exist between the magnetic parameters and the contents of Pb, Cu and Fe. The magnetic parameters of automobile emission particulates reflecting concentration of magnetic particles increased linearly with increase of Pb and Cu content, showed that the magnetic measurement could be used as a preliminary index for detection of Pb and Cu pollution.

Enhancement of nitric oxide production by methylecgonidine in cultured neonatal rat cardiomyocytes.

1. In the present experiments, we investigated the effects of methylecgonidine (MEG) on nitric oxide (NO) production in cultured neonatal rat cardiomyocytes. Incubation of cultured cardiomyocytes with carbachol or MEG for 48 h significantly enhanced NO production. No release was increased from 1.48+/-0.13 microM (mg protein)(-1) for control to 5.73+/-0.19 microM (mg protein)(-1) for 1 microM carbachol treated cells (P<0.001). In addition, incubation with 1 microM MEG enhanced NO production to 5.55+/-0.28 microM (mg protein)(-1). The effects of MEG on NO production were concentration-dependent. The muscarinic antagonist atropine prevented the enhancement of NO production induced by carbachol or MEG. Compared to MEG-induced NO production, cocaine was much less potent. 2. The enhancement of NO production by carbachol or MEG was even greater in cultured cardiomyocytes transfected with the M(2) cDNA. After 48-h incubation with 1 microM carbachol or 1 microM MEG, NO production was increased by 6.5 and 6.7 fold, respectively, in cardiomyocytes overexpressing M(2) receptors. Coincubation with atropine or N(G)-nitro-L-arginine methyl ester abolished the enhancement of NO production. In contrast, NO production enhanced by carbachol or MEG in M(1)- or M(3)-transfected cardiomyocytes was similar to the level in non-transfected cells. 3. Western blot analysis showed that the protein levels of M(1), M(2), and M(3) were significantly increased in cardiomyocytes transfected with the receptor cDNAs, but MEG had no effect on the expressions. It is interesting that both carbachol and MEG caused a significant increase in constitutive endothelial NO synthase (eNOS) only in M(2)-transfected cardiomyocytes, not in non-transfected, M(1)- or M(3)-transfected cells. Again, atropine blocked the MEG-produced induction of eNOS. 4. Our data demonstrate that MEG significantly enhanced NO production in cultured cardiomyocytes and that the enhancement of NO production may result from MEG stimulation of muscarinic M(2) receptors.

Hybrid integration of conventional waveguide and photonic crystal structures.

We propose the hybrid integration of conventional index-guided waveguides (CWGs) and photonic crystal (PhC) regions of very limited spatial extent as a promising path toward large-scale planar lightwave circuit (PLC) integration. In CWG/PhC structures the PhC regions do not perform the function of waveguiding, but instead augment the CWGs to permit a drastic reduction in the size of photonic components. For single mode waveguides with a refractive index contrast of only 2.3%, simulation results show a 90 degree bend with 98.7% efficiency, a compact beamsplitter with 99.4% total efficiency, and a planar Mach-Zender interferometer (MZI) with 97.8% efficiency. The MZI occupies an area of only 18microm m x 18 microm.

New ring resonator configuration using hybrid photonic crystal and conventional waveguide structures.

We propose a new method of realizing ring resonators based on hybrid photonic crystal and conventional waveguide structures. The proposed ring resonator configuration is advantageous compared with general ring resonator structures for its controllability of the quality (Q) factor, free spectral range (FSR), and full width at half maximum (FWHM) over a wide range. We show ring resonator structures based on a single mode waveguide with core and clad refractive indices of 1.5 and 1.465, respectively. A 35mum x 50mum ring resonator has a free spectral range (FSR) of 14.1nm and a quality (Q) factor of 595 with high optical efficiency (92.7%). By decreasing the size of the ring resonator to 35mum x 35mum, the FSR is increased to 19.8nm. Modifying the splitting ratio of the beam splitters permits the Q factor to be increased to 1600.

VEGF enhances functional improvement of postinfarcted hearts by transplantation of ESC-differentiated cells.

Despite considerable advances in medicine, the incidence of heart failure remains high in patients after myocardial infarction (MI). This study investigated the effects of engrafted early-differentiated cells (EDCs) from mouse embryonic stem cells, with or without transfection of vascular endothelial growth factor (VEGF) cDNA (phVEGF(165)), on cardiac function in postinfarcted mice. EDCs were transfected with green fluorescent protein (GFP) cDNA and transplanted into infarcted myocardium. Compared with the MI mice receiving cell-free medium, cardiac function was significantly improved in the MI mice 6 wk after transplantation of EDCs. Moreover, improvement of heart function was significantly greater in the mice implanted with EDCs overexpressing VEGF (EDCs-VEGF) than with EDCs alone. Frozen sections of infarcted myocardium with EDCs or EDCs-VEGF transplantation showed GFP-positive tissue. The area with positive immunostaining for cardiac troponin I and alpha-myosin heavy chain was larger in injured myocardium with EDCs or EDCs-VEGF transplantation than with medium injection. Transplantation of EDCs or EDCs-VEGF significantly increased the number of blood vessels in the MI area. However, the density of capillaries was significantly higher in the EDCs-VEGF animals than in the EDC mice. Double staining for GFP and connexin-43 was positive in injured myocardium with EDC transplantation. Our data demonstrate that engrafted EDCs or EDCs-VEGF regenerated cardiac tissue and significantly improved cardiac function in postinfarcted hearts. The novel EDCs-VEGF synergistic approach may have an important impact on future cell therapy for patients experiencing MI or heart failure.

Three sulphated polysaccharides isolated from the mucilage of mud snail, Bullacta exarata philippi: characterization and antitumour activity.

Three sulphated polysaccharides, coded as BEMPA, BEMPB(1), BEMPB(2), were extracted from the mucilage of mud snail of Bullacta exarata and purified by DEAE-cellulose ion-exchange and size-exclusion chromatography. Structural analysis of purified polysaccharides by chemical and biochemical methods revealed BEMPA was a high (1→3,4)-linked mannose-containing polysaccharide with molecular weight of 22,977 Da. BEMPB(1), with molecular weight of 64,117 Da, was a high (1→3)-linked arabinose-containing polysaccharide. BEMPB(2) was mainly composed of (1→3,4)-linked mannose with molecular weight of 47,507Da. The comparison between sulphated polysaccharides and their desulphated products showed that sulphate substitutions of BEMPB(1) were deduced to be at the C-3 of (1→4)-linked mannose, while sulphate substitutions of BEMPA and BEMPB(2) were at C-4 of (1→3)-linked mannose. Furthermore, BEMPA exhibited highest inhibitory effects on growth of B-16 melanoma cells, and IC(50) were 31.1 µg/mL.

Rapid component I(Kr) of cardiac delayed rectifier potassium currents in guinea-pig is inhibited by alpha(1)-adrenoreceptor activation via protein kinase A and protein kinase C-dependent pathways.

Ventricular tachyarrhythmias are often precipitated by physical or emotional stress, indicating a link between increased adrenergic stimulation and cardiac ion channel activity. Human ether-a-go-go related gene (hERG) potassium channels conduct the rapid component of delayed rectifier potassium current, I(kr), a crucial component for action potential repolarization. To evaluate the correlation between increased alpha(1)-adrenergic activity and the rapid component of cardiac I(kr), whole-cell patch-clamp recording was performed in isolated guinea-pig ventricular myocytes. Stimulation of alpha(1)-adrenoceptors using phenylephrine (0.1 nM-100 microM) reduced I(kr) current in a dose-dependent manner at 37 degrees C. Phenylephrine (0.1 microM) reduced I(kr) current to 66.83+/-3.16%. Chelerythrine (1 microM), a specific inhibitor of protein kinase C (PKC) completely inhibited the changes in I(kr) trigged by 0.1 microM phenylephrine. KT5720 (2.5 microM), a specific inhibitor of protein kinase A (PKA) partially inhibited the current decrease induced by 0.1 microM phenylephrine. Both chelerythrine and KT5720 drastically reduced the phenylephrine-induced effects, indicating possible involvement of PKC and PKA in the alpha(1)-adrenergic inhibition of I(kr). Our data suggest a link between I(kr) and the alpha(1)-adrenoceptor, involving activation of PKC and PKA in arrhythmogenesis.

Stratified waveguide grating coupler for normal fiber incidence.

We propose a new stratified waveguide grating coupler (SWGC) to couple light from a fiber at normal incidence into a planar waveguide. SWGCs are designed to operate in the strong coupling regime without intermediate optics between the fiber and the waveguide. Two-dimensional finite-difference time-domain simulation in conjunction with microgenetic algorithm optimization shows that approximately 72% coupling efficiency is possible for fiber (core size of 8.3 microm and delta=0.36%) to slab waveguide (1.2-microm core and delta=3.1%) coupling. We show that the phase-matching and Bragg conditions are simultaneously satisfied through the fundamental leaky mode.

Parallel microgenetic algorithm design for photonic crystal and waveguide structures.

We have developed a powerful parallel genetic algorithm design tool for photonic crystal and waveguide structures. The tool employs a small-population-size genetic algorithm (microgenetic algorithm) for global optimization and a two-dimensional finite-difference time-domain method to rigorously design and optimize the performance of photonic devices. We discuss the implementation and performance of this design tool. We demonstrate its application to two photonic devices, a defect taper coupler to connect conventional waveguides and photonic crystal waveguides, and a sharp 90 degrees waveguide bend for low index contrast waveguides.