Extratropical cyclone climatology across eastern Canada

Plante, Mathieu,Son, Seok‐,Woo,Atallah, Eyad,Gyakum, John,Grise, Kevin John Wiley Sons, Ltd 2015 International journal of climatology Vol.35 No.10

<P><B>ABSTRACT</B></P><P>Extratropical cyclone (ETC) tracks across eastern Canada are examined by applying a Lagrangian tracking algorithm to the lower‐tropospheric relative vorticity field of reanalysis data. Both the seasonal cycle and the interannual variability of ETCs are quantified in terms of overall cyclone frequency, intensity, and regions of development and decay. We find that ETCs travelling to eastern Canada tend to develop over the Rockies, the Great Lakes and the US East Coast. The ETCs are most intense over Newfoundland and the North Atlantic Ocean, confirming previous findings. While ETCs at cities along the Atlantic coastline (e.g. St. John's) are dominated by East Coast cyclones (which are intense in winter), those inland (e.g. Toronto) track primarily from the Great Lakes. ETCs that develop over the Gulf of Mexico affect eastern Canada infrequently, but those that do tend to be intense. The interannual variability of the wintertime ETCs is influenced by the El Niño‐Southern Oscillation (ENSO). Significant ENSO‐related variability is found over most regions of southern Canada, except on the east coast. Although ETCs at Toronto are significantly modulated by ENSO, no visible changes are found at St. John's. These ENSO‐related ETC changes are mostly due to the shifts in ETC development regions, with minor changes in the travelling direction of ETCs.</P>

Layer-by-layer AuCl3 doping of stacked graphene films

Oh, S.,Kim, B. J.,Kim, J. John Wiley Sons, Ltd 2014 Physica Status Solidi. Rapid Research Letters Vol.8 No.5

We investigated the effect of layer-by-layer AuCl3 doping on the electrical and optical properties of stacked graphene films. Graphene grown by the chemical-vapor deposition method on a Cu-foil was chemically doped by AuCl3 solution with a concentration of 20 mM. Eight different configurations were prepared and analyzed by using four-point probe measurements, optical transmittance measurements, scanning electron microscopy, and micro-Raman spectroscopy to compare the optical and electrical characteristics of the different graphene samples. In our study, the top-layer doping method was very effective because better performances considering both sheet resistance and optical transmittance were observed from the configurations with the top-layer doped. ((c) 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Fragmentation and development of preimplantation porcine embryos derived by parthenogenetic activation and nuclear transfer

Im, Gi-Sun,Yang, Boh-Suk,Lai, Liangxue,Liu, Zhonghua,Hao, Yanhong,Prather, Randall S. JOHN WILEY & SONS LTD 2005 Molecular Reproduction and Development Vol.71 No.2

<P>Fragmentation occurs during early developmental stages of electrically activated oocytes and nuclear transfer (NT) embryos. It might contribute to the low developmental rate of porcine NT embryos. The present study was conducted to investigate whether the addition of sugars such as sorbitol or sucrose suppresses fragmentation and supports the development of electrically activated oocytes and NT embryos. The activated oocytes were cultured in Porcine Zygote Medium-3 (PZM-3) supplemented with sorbitol or sucrose for 2 days after electric activation, and then cultured in the PZM-3 for the remaining 4 days. The osmolarities of PZM-3, PZM-3 supplemented with 0.05 or 0.1 M sorbitol, and PZM-3 with 0.05 M sucrose were 269 ± 6.31, 316 ± 3.13, 362 ± 4.37, and 315 ± 5.03 mOsm, respectively. When parthenogentically activated oocytes were cultured in PZM-3 supplemented with 0.05 M sorbitol or sucrose for the first 2 days and then cultured in PZM-3 without sugar, a significantly higher (P < 0.05) cleavage rate and blastocyst rate were observed. Interestingly, addition of sugar to PZM-3 for 2 days reduced the fragmentation rate compared to PZM-3 without sugar. In NT embryos, sugar addition into PZM-3 increased the fusion rate (84.2% ± 6.07 vs. 95.1% ± 2.52), cleavage rate (67.6% ± 5.80 vs. 77.3% ± 3.03), and developmental rate to the blastocyst stage (10.2% ± 0.79 vs. 19.4% ± 1.77). There was no significant difference between treatments for the number of the blastocysts. In addition the fragmentation rate was reduced compared to PZM-3 without sorbitol (26.1 ± 4.30 vs. 14.5 ± 1.74). In conclusion, increasing the osmolarity of PZM-3 through addition of either sorbitol or sucrose for 48 hr increased the cleavage and developmental rate to the blastocyst stage by reducing the fragmentation rate through increasing osmolarity. Mol. Reprod. Dev. 71: 159–165, 2005. © 2005 Wiley-Liss, Inc.</P>

Downregulation of GFAP, TSP-1, and p53 in human glioblastoma cell line, U373MG, by IE1 protein from human cytomegalovirus

Lee, Karim,Jeon, Kipyoung,Kim, Jong-Mook,Kim, Vic Narry,Choi, Dong Hee,Kim, Seung U.,Kim, Sunyoung John Wiley & Sons, Inc. 2005 Glia Vol.51 No.1

<P>Human cytomegalovirus (HCMV) is a member of the β-herpesvirus family, which has tropism for glial cells. It was recently reported that HCMV might play important roles in the pathogenesis of malignant glioma. In this study, we investigated the effects of the HCMV IE1 protein on the gene expression profile in the human glioblastoma cell line, U373MG by employing cDNA microarray technology. Using DNA chips containing approximately 1,000 human cDNAs, RNA samples from U373MG cells stably expressing IE1 were compared with those from the control cells lacking IE1 cDNA. Fluorescence intensities of 13 genes were significantly decreased in IE1-expressing cells, while one gene was found to be upregulated. Among these 14 genes, we chose to work further on glial fibrillary acidic protein (GFAP), thrombospondin-1 (TSP-1), and p53, because of their previously known involvement in tumorigenesis. The mRNA levels of all these genes were found to be decreased in IE1-expressing glioblastoma cells by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) as well as Northern blot analysis. The decreased expression of these genes was also observed at protein levels as measured by immunocytochemistry or fluorescence-activated cell sorting (FACS) analysis. Our data strongly suggested that HCMV IE1 could modulate the expression of cellular genes that might play important roles in the pathogenesis of glial tumors. © 2005 Wiley-Liss, Inc.</P>

Cdc42 is implicated in polarity during meiotic resumption and blastocyst formation in the mouse

Cui, Xiang-Shun,Li, Xing-Yu,Kim, Nam-Hyung JOHN WILEY & SONS LTD 2007 MOLECULAR REPRODUCTION AND DEVELOPMENT Vol.74 No.6

<P>Cell division cycle 42 (Cdc42), a member of the Rho family of small guanosine triphosphatase (GTPase) proteins, regulates multiple cell functions, including: motility, proliferation, apoptosis, and cell morphology. In order to obtain insight into the role of Cdc42 in meiotic resumption and embryo development, we first evaluated its gene expression levels in mouse oocytes and embryos during in vitro development. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) revealed high-expression levels in GV stage oocytes that steadily decreased up to the 2-cell (2C) stage embryo, and then expression increased during morulae and blastocyst formation. Indirect Immunocytochemistry also showed protein synthesis of CDC42 in the mouse oocytes and early embryos. Introducing small interference RNA (siRNA) of Cdc42 into germinal vesicle stage oocytes or zygotes specifically reduced both mRNA expression and protein synthesis of CDC42 in in vitro developed metaphase II oocytes and early embryos. Meiotic maturation and cytoskeleton assembly were significantly altered following siRNA injection into germinal vesicle stage oocytes. Injection of siRNA into the zygote did not affect cleavage or cell numbers in morulae, but significantly decreased in vitro development to the morula or blastocyst. These findings suggest that gene expression of Cdc42 is involved in meiotic resumption and blastocyst formation in the mouse, possibly through maintaining polarity. Mol. Reprod. Dev. 74: 785–794, 2007. © 2006 Wiley-Liss, Inc.</P>

Effects of calcitonin and parathyroid hormone on the regulation of cabindin-D_9k in the uterus, placenta, and fetal membrane of rats related to blood calcium level during late gestation

Hong, Eui-Ju,Choi, Kyung-Chul,Hyun, Sang-Hwan,Jeung, Eui-Bae JOHN WILEY & SONS LTD 2007 MOLECULAR REPRODUCTION AND DEVELOPMENT Vol.74 No.9

<P>Calbindin-D<SUB>9k</SUB> (CaBP-9k) gene is expressed in the uterus of pregnant rats, which is regulated by steroid hormones during estrous cycle or gestation. We hypothesized that there is a positive correlation between altered CaBP-9k expression and change in one or more of the hormones to provide a clue to the mechanism responsible for the altered calcium levels in the uterus, placenta, and fetal membrane during late gestation. Thus, in the present study, we investigated the effects of the hormones including estradiol (E2), calcitonin (CT), and parathyroid hormone (PTH) on the regulation of CaBP-9k in these tissues. There was an increase in the level of CaBP-9k in the uterus, placenta, and extra-embryonic membrane at late gestation, as blood calcium level increased. The protein level of CaBP-9k remained lower in the uterus at two-thirds of pregnancy, and then it rebounded abruptly during late pregnancy. During late gestation, E2 is postulated to be a dominant factor in the regulation of uterine CaBP-9k gene expression. Furthermore, we assumed that there is a positive correlation between altered expression of CaBP-9k and blood calcium level during pregnancy. The present study demonstrated the regulation of CaBP-9k mRNA in the uterus, placenta, and fetal membrane of rats, implying a role for CaBP-9k gene in the control of blood calcium in placenta and the calcium passing from maternal blood to fetal circulation. Taken together, these results suggest that major alterations in calcium metabolism caused by maternal thyroparathyroidectomy (TPTX), are sufficient to affect the changes in reproductive tissues during late pregnancy. In addition, an increase of blood calcium level is one of the most significant factors in the regulation of CaBP-9k at the transcriptional and/or translational levels in the reproductive tissues during late pregnancy. Mol. Reprod. Dev. 74: 1188–1197, 2007. © 2007 Wiley-Liss, Inc.</P>

Tetracycline-inducible gene expression in nuclear transfer embryos derived from porcine fetal fibroblasts transformed with retrovirus vectors

Choi, Bok Ryul,Koo, Bon Chul,Ahn, Kwang Sung,Kwon, Mo Sun,Kim, Jin-Hoi,Cho, Seong-Keun,Kim, Kyoung Mi,Kang, Jee Hyun,Shim, Hosup,Lee, Hyuna,Uhm, Sang Jun,Lee, Hoon Taek,Kim, Teoan JOHN WILEY & SONS LTD 2006 MOLECULAR REPRODUCTION AND DEVELOPMENT Vol.73 No.10

<P>A critical problem of transgenic livestock production is uncontrollable constitutive expression of the foreign gene, which usually results in serious physiological disturbances in transgenic animals. One of the best solutions for this problem may be use of controllable gene expression system. In this study, using retrovirus vectors designed to express the enhanced green fluorescent protein (EGFP) gene under the control of the tetracycline-inducible promoter, we examined whether the expression of the transgene could be controllable in fibroblast cells and nuclear transfer (NT) embryos of porcine. Transformed fibroblast cells were cultured in medium supplemented with or without doxycycline (a tetracycline analog) for 48 hr, and the induction efficiency was measured by comparing EGFP gene expression using epifluorescence microscopy and Western and Northern blot analyses. After the addition of doxycycline, EGFP expression increased up to 17-fold. The nuclei of transformed fibroblast cells were transferred into enucleated oocytes. Fluorescence emission data revealed strong EGFP gene expression in embryos cultured with doxycycline, but little or no expression in the absence of the antibiotic. Our results demonstrate the successful regulation of transgene expression in porcine nuclear transfer embryos, and support the application of an inducible expression system in transgenic pig production to solve the inherent problems of side-effects due to constitutive expression of the transgene. Mol. Reprod. Dev. © 2006 Wiley-Liss, Inc.</P>

In vitro development and cell allocation of porcine blastocysts derived by aggregation of in vitro fertilized embryos

Lee, Sang-Goo,Park, Chi-Hun,Choi, Don-Ho,Kim, Hye-Sun,Ka, Hak-Hyun,Lee, Chang-Kyu JOHN WILEY & SONS LTD 2007 MOLECULAR REPRODUCTION AND DEVELOPMENT Vol.74 No.11

<P>In pigs, the morphology and cell number of in vitro-produced blastocysts are inferior to those of their in vivo counterparts. The objective of this study was to increase developmental competence and to gain an understanding of cell allocation in blastocysts derived from the aggregation of four-cell stage porcine embryos produced in vitro. After removal of the zona pellucida, two (2×) and three (3×) four-cell stage embryos were aggregated by co-culturing them in aggregation plates. Five days after aggregation, the developmental ability and the number of cells in the aggregated embryos were determined. The percentage of blastocysts was higher (P < 0.05) in both the 2× and 3× aggregated embryos (66.6% and 72.0%, respectively) compared to that of the 1× embryos and the intact controls (43.1% and 36.4%, respectively). The total cell number of blastocysts also increased in aggregated embryos compared to that of intact controls (2.6-fold for 2× and 3.4-fold for 3×) (P < 0.05). The cells of two differentially stained embryos were started to mix at 72 hr after aggregation. In vitro-fertilized porcine aggregates (2×) were developed to blastocyst with a random distribution of cells from each embryo. The mRNA levels for the oct-4, bcl-xL and connexin 43 genes were higher (P < 0.05) and bak gene were lower (P < 0.05) in both the 2× and 3× aggregated embryos than the intact controls. Therefore, the aggregation of the four-cell stage embryos could be used to improve the quality of porcine preimplantation stage embryos produced in vitro. Mol. Reprod. Dev. 74: 1436–1445, 2007. © 2007 Wiley-Liss, Inc.</P>

Ectopic expression of Tollo/Toll-8 antagonizes Dpp signaling and induces cell sorting in the Drosophila wing

Kim, Sangjoon,Chung, SeYeon,Yoon, Jeongsook,Choi, Kwang-Wook,Yim, Jeongbin John Wiley & Sons 2006 Genesis Vol.44 No.11

<P>The wing imaginal disc of Drosophila consists of the primordia for the adult wing and the body wall. The zinc-finger transcription factor Teashirt (Tsh) is expressed in the region proximal to the wing primordium and regulates the formation of the wing-body wall boundary. Here, we report that Tollo/Toll-8, a member of Toll family transmembrane proteins, is also expressed proximal to the wing domain. Ectopic expression of Decapentaplegic (Dpp), a morphogen for wing development, represses tollo expression in the proximal domain. Likewise, misexpression of Tollo in the presumptive wing strongly antagonizes the effects of Dpp signaling. The extracellular domain of Tollo containing the Leucine-Rich Repeats (LRR) is required for the inhibition of Dpp signaling in the wing. Furthermore, clones of cells with Tollo overexpression are sorted out from the surrounding wild-type cells, resulting in the formation of epithelial folds around the clone boundaries. Tsh is ectopically induced at the border of Tollo-expressing clones. Despite the strong effects of Tollo overexpression on Dpp signaling and cell sorting, loss-of-function tollo mutants are viable with normal external morphology. Our data suggest that Tollo function might be redundant but is sufficient to antagonize Dpp signaling and induce sorting of Tollo expressing cells from the wing cells to develop proximal cell fate. genesis 44:541–549, 2006. © 2006 Wiley-Liss, Inc.</P>

Resident microglia die and infiltrated neutrophils and monocytes become major inflammatory cells in lipopolysaccharide-injected brain

Ji, Kyung-Ae,Yang, Myung-Soon,Jeong, Hey-Kyeong,Min, Kyoung-Jin,Kang, Seung-Hee,Jou, Ilo,Joe, Eun-Hye John Wiley & Sons, Inc. 2007 Glia Vol.55 No.15

<P>Generally, it has been accepted that microglia play important roles in brain inflammation. However, recently several studies suggested possible infiltration of blood neutrophils and monocytes into the brain. To understand contribution of microglia and blood inflammatory cells to brain inflammation, the behavior of microglia, neutrophils, and monocytes was investigated in LPS (lipopolysaccharide)-injected substantia nigra pars compacta, cortex, and hippocampus of normal and/or leukopenic rats using specific markers of neutrophils (myeloperoxidase, MPO), and microglia and monocytes (ionized calcium binding adaptor molecule-1, Iba-1), as well as a general marker for these inflammatory cells (CD11b). CD11b-immunopositive (CD11b<SUP>+</SUP>) cells and Iba-1<SUP>+</SUP> cells displayed similar behavior in intact and LPS-injected brain at 6 h after the injection. Interestingly, however, CD11b<SUP>+</SUP> cells and Iba-1<SUP>+</SUP> cells displayed significantly different behavior at 12 h: Iba-1<SUP>+</SUP> cells disappeared while CD11b<SUP>+</SUP> cells became round in shape. We found that CD11b/Iba-1-double positive (CD11b<SUP>+</SUP>/Iba-1<SUP>+</SUP>) ramified microglia died within 6 h after LPS injection. The round CD11b<SUP>+</SUP> cells detected at 12 h were MPO<SUP>+</SUP>. These CD11b<SUP>+</SUP>/MPO<SUP>+</SUP> cells were not found in leukopenic rats, suggestive of neutrophil infiltration. MPO<SUP>+</SUP> neutrophils expressed inducible nitric oxide synthase, interleukin-1β, cyclooxygenase-2, and monocyte chemoattractant protein-1, but died within 18 h. CD11b<SUP>+</SUP> cells detected at 24 h appeared to be infiltrated monocytes, since these cells were once labeled with Iba-1 and were not found in leukopenic rats. Furthermore, transplanted monocytes were detectable in LPS-injected brain. These results suggest that at least a part of neutrophils and monocytes could have been misinterpreted as activated microglia in inflamed brain. © 2007 Wiley-Liss, Inc.</P>