Structural basis for recognition of human 7SK long noncoding RNA by the La-related protein Larp7.
Eichhorn, Catherine D; Yang, Yuan; Repeta, Lucas; Feigon, Juli
2018-06-26
The La and the La-related protein (LARP) superfamily is a diverse class of RNA binding proteins involved in RNA processing, folding, and function. Larp7 binds to the abundant long noncoding 7SK RNA and is required for 7SK ribonucleoprotein (RNP) assembly and function. The 7SK RNP sequesters a pool of the positive transcription elongation factor b (P-TEFb) in an inactive state; on release, P-TEFb phosphorylates RNA Polymerase II to stimulate transcription elongation. Despite its essential role in transcription, limited structural information is available for the 7SK RNP, particularly for protein-RNA interactions. Larp7 contains an N-terminal La module that binds UUU-3'OH and a C-terminal atypical RNA recognition motif (xRRM) required for specific binding to 7SK and P-TEFb assembly. Deletion of the xRRM is linked to gastric cancer in humans. We report the 2.2-Å X-ray crystal structure of the human La-related protein group 7 (hLarp7) xRRM bound to the 7SK stem-loop 4, revealing a unique binding interface. Contributions of observed interactions to binding affinity were investigated by mutagenesis and isothermal titration calorimetry. NMR 13 C spin relaxation data and comparison of free xRRM, RNA, and xRRM-RNA structures show that the xRRM is preordered to bind a flexible loop 4. Combining structures of the hLarp7 La module and the xRRM-7SK complex presented here, we propose a structural model for Larp7 binding to the 7SK 3' end and mechanism for 7SK RNP assembly. This work provides insight into how this domain contributes to 7SK recognition and assembly of the core 7SK RNP.
hLARP7 C-terminal domain contains an xRRM that binds the 3' hairpin of 7SK RNA
Eichhorn, Catherine D.; Chug, Rahul; Feigon, Juli
2016-09-26
The 7SK small nuclear ribonucleoprotein (snRNP) sequesters and inactivates the positive transcription elongation factor b (P-TEFb), an essential eukaryotic mRNA transcription factor. The human La-related protein group 7 (hLARP7) is a constitutive component of the 7SK snRNP and localizes to the 3' terminus of the 7SK long noncoding RNA. hLARP7, and in particular its C-terminal domain (CTD), is essential for 7SK RNA stability and assembly with P-TEFb. The hLARP7 N-terminal Lamodule binds and protects the 3' end from degradation, but the structural and functional role of its CTD is unclear.We report the solution NMR structure of the hLARP7 CTD andmore » show that this domain contains an xRRM, a class of atypical RRM first identified in the Tetrahymena thermophila telomerase LARP7 protein p65. The xRRM binds the 3' end of 7SK RNA at the top of stem-loop 4 (SL4) and interacts with both unpaired and base-paired nucleotides. This study thus confirms that the xRRM is general to the LARP7 family of proteins and defines the binding site for hLARP7 on the 7SK RNA, providing insight into function.« less
hLARP7 C-terminal domain contains an xRRM that binds the 3' hairpin of 7SK RNA
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eichhorn, Catherine D.; Chug, Rahul; Feigon, Juli
The 7SK small nuclear ribonucleoprotein (snRNP) sequesters and inactivates the positive transcription elongation factor b (P-TEFb), an essential eukaryotic mRNA transcription factor. The human La-related protein group 7 (hLARP7) is a constitutive component of the 7SK snRNP and localizes to the 3' terminus of the 7SK long noncoding RNA. hLARP7, and in particular its C-terminal domain (CTD), is essential for 7SK RNA stability and assembly with P-TEFb. The hLARP7 N-terminal Lamodule binds and protects the 3' end from degradation, but the structural and functional role of its CTD is unclear.We report the solution NMR structure of the hLARP7 CTD andmore » show that this domain contains an xRRM, a class of atypical RRM first identified in the Tetrahymena thermophila telomerase LARP7 protein p65. The xRRM binds the 3' end of 7SK RNA at the top of stem-loop 4 (SL4) and interacts with both unpaired and base-paired nucleotides. This study thus confirms that the xRRM is general to the LARP7 family of proteins and defines the binding site for hLARP7 on the 7SK RNA, providing insight into function.« less
Many-body interaction effects on the low-k structure of liquid Kr
NASA Astrophysics Data System (ADS)
Guarini, E.; Magli, R.; Tau, M.; Barocchi, F.; Casanova, G.; Reatto, L.
2001-05-01
Neutron diffraction measurements and theoretical calculations of the structure factor S(k) of liquid Kr are extended to small k values (k<4 nm-1). The results show that many-body interaction contributions have an increasing effect on S(k) as k-->0, reaching at least 40% of the measured intensity. Both the phase diagram and the low-k structural data of dense Kr turn out to be closely reproduced by the hierarchical reference theory if additional many-body forces are taken into account by an augmented strength of the Axilrod-Teller triple-dipole potential. The experimental density derivative of S(k) is also used for a very sensitive test of the theories and interaction models considered here.
Zels, Sven; Dillen, Senne; Crabbé, Katleen; Spit, Jornt; Nachman, Ronald J; Vanden Broeck, Jozef
2015-06-01
Sulfakinin (SK) is a sulfated insect neuropeptide that is best known for its function as a satiety factor. It displays structural and functional similarities with the vertebrate peptides gastrin and cholecystokinin. Peptidomic studies in multiple insects, crustaceans and arachnids have revealed the widespread occurrence of SK in the arthropod phylum. Multiple studies in hemi- and holometabolous insects revealed the pleiotropic nature of this neuropeptide: in addition to its activity as a satiety factor, SK was also reported to affect muscle contraction, digestive enzyme release, odor preference, aggression and metabolism. However, the main site of action seems to be the digestive system of insects. In this study, we have investigated whether SK can intervene in the control of nutrient uptake and digestion in the migratory locust (Locusta migratoria). We provide evidence that sulfakinin reduces food uptake in this species. Furthermore, we discovered that SK has very pronounced effects on the main digestive enzyme secreting parts of the locust gut. It effectively reduced digestive enzyme secretion from both the midgut and gastric caeca. SK injection also elicited a reduction in absorbance and proteolytic activity of the gastric caeca contents. The characteristic sulfation of the tyrosine residue is crucial for the observed effects on digestive enzyme secretion. In an attempt to provide potential leads for the development of peptidomimetic compounds based on SK, we also tested two mimetic analogs of the natural peptide ligand in the digestive enzyme secretion assay. These analogs were able to mimic the effect of the natural SK, but their effects were milder. The results of this study provide new insights into the action of SK on the digestive system in (hemimetabolous) insects. Copyright © 2015 Elsevier Ltd. All rights reserved.
The SK3 channel promotes placental vascularization by enhancing secretion of angiogenic factors.
Rada, Cara C; Murray, Grace; England, Sarah K
2014-11-15
Proper placental perfusion is essential for fetal exchange of oxygen, nutrients, and waste with the maternal circulation. Impairment of uteroplacental vascular function can lead to pregnancy complications, including preeclampsia and intrauterine growth restriction (IUGR). Potassium channels have been recognized as regulators of vascular proliferation, angiogenesis, and secretion of vasoactive factors, and their dysfunction may underlie pregnancy-related vascular diseases. Overexpression of one channel in particular, the small-conductance calcium-activated potassium channel 3 (SK3), is known to increase vascularization in mice, and mice overexpressing the SK3 channel (SK3(T/T) mice) have a high rate of fetal demise and IUGR. Here, we show that overexpression of SK3 causes fetal loss through abnormal placental vascularization. We previously reported that, at pregnancy day 14, placentas isolated from SK3(T/T) mice are smaller than those obtained from wild-type mice. In this study, histological analysis reveals that SK3(T/-) placentas at this stage have abnormal placental morphology, and microcomputed tomography shows that these placentas have significantly larger and more blood vessels than those from wild-type mice. To identify the mechanism by which these vascularization defects occur, we measured levels of vascular endothelial growth factor (VEGF), placental growth factor, and the soluble form of VEGF receptor 1 (sFlt-1), which must be tightly regulated to ensure proper placental development. Our data reveal that overexpression of SK3 alters systemic and placental ratios of the angiogenic factor VEGF to antiangiogenic factor sFlt-1 throughout pregnancy. Additionally, we observe increased expression of hypoxia-inducing factor 2α in SK3(T/-) placentas. We conclude that the SK3 channel modulates placental vascular development and fetal health by altering VEGF signaling. Copyright © 2014 the American Physiological Society.
Learning Activities for International Business.
ERIC Educational Resources Information Center
Haynes, Thomas
1998-01-01
The National Standards for Business Education include nine areas relating to international business: awareness, communication, environmental factors, ethics, finance, management, marketing, import/export, and organizational structure of international business. (SK)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stiegler,A.; Burden, S.; Hubbard, S.
Muscle-specific kinase (MuSK) is a receptor tyrosine kinase expressed exclusively in skeletal muscle, where it is required for formation of the neuromuscular junction. MuSK is activated by agrin, a neuron-derived heparan sulfate proteoglycan. Here, we report the crystal structure of the agrin-responsive first and second immunoglobulin-like domains (Ig1 and Ig2) of the MuSK ectodomain at 2.2 {angstrom} resolution. The structure reveals that MuSK Ig1 and Ig2 are Ig-like domains of the I-set subfamily, which are configured in a linear, semi-rigid arrangement. In addition to the canonical internal disulfide bridge, Ig1 contains a second, solvent-exposed disulfide bridge, which our biochemical datamore » indicate is critical for proper folding of Ig1 and processing of MuSK. Two Ig1-2 molecules form a non-crystallographic dimer that is mediated by a unique hydrophobic patch on the surface of Ig1. Biochemical analyses of MuSK mutants introduced into MuSK{sup -/-} myotubes demonstrate that residues in this hydrophobic patch are critical for agrin-induced MuSK activation.« less
Crystal Structure of the Frizzled-Like Cysteine-Rich Domain of the Receptor Tyrosine Kinase MuSK
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stiegler, A.; Burden, S; Hubbard, S
Muscle-specific kinase (MuSK) is an essential receptor tyrosine kinase for the establishment and maintenance of the neuromuscular junction (NMJ). Activation of MuSK by agrin, a neuronally derived heparan-sulfate proteoglycan, and LRP4 (low-density lipoprotein receptor-related protein-4), the agrin receptor, leads to clustering of acetylcholine receptors on the postsynaptic side of the NMJ. The ectodomain of MuSK comprises three immunoglobulin-like domains and a cysteine-rich domain (Fz-CRD) related to those in Frizzled proteins, the receptors for Wnts. Here, we report the crystal structure of the MuSK Fz-CRD at 2.1 {angstrom} resolution. The structure reveals a five-disulfide-bridged domain similar to CRDs of Frizzled proteinsmore » but with a divergent C-terminal region. An asymmetric dimer present in the crystal structure implicates surface hydrophobic residues that may function in homotypic or heterotypic interactions to mediate co-clustering of MuSK, rapsyn, and acetylcholine receptors at the NMJ.« less
ERIC Educational Resources Information Center
McRae, Mary B.
1990-01-01
The overrepresentation of Black females in traditional occupations stems from the emotions, beliefs, and environmental factors affecting their decision making. Conflicts between sex role socialization and that of Black subculture, as well as discrimination in hiring, are contributing factors. (SK)
Park, Chong Yon; Pierce, Stephanie A; von Drehle, Morgan; Ivey, Kathryn N; Morgan, Jayson A; Blau, Helen M; Srivastava, Deepak
2010-11-30
Cardiac and skeletal muscle development and maintenance require complex interactions between DNA-binding proteins and chromatin remodeling factors. We previously reported that Smyd1, a muscle-restricted histone methyltransferase, is essential for cardiogenesis and functions with a network of cardiac regulatory proteins. Here we show that the muscle-specific transcription factor skNAC is the major binding partner for Smyd1 in the developing heart. Targeted deletion of skNAC in mice resulted in partial embryonic lethality by embryonic day 12.5, with ventricular hypoplasia and decreased cardiomyocyte proliferation that were similar but less severe than in Smyd1 mutants. Expression of Irx4, a ventricle-specific transcription factor down-regulated in hearts lacking Smyd1, also depended on the presence of skNAC. Viable skNAC(-/-) adult mice had reduced postnatal skeletal muscle growth and impaired regenerative capacity after cardiotoxin-induced injury. Satellite cells isolated from skNAC(-/-) mice had impaired survival compared with wild-type littermate satellite cells. Our results indicate that skNAC plays a critical role in ventricular cardiomyocyte expansion and regulates postnatal skeletal muscle growth and regeneration in mice.
NASA Astrophysics Data System (ADS)
Alzubadi, A. A.
2015-06-01
Nuclear many-body system is usually described by a mean-field built upon a nucleon-nucleon effective interaction. In this work, we investigate ground state properties of the sulfur isotopes covering a wide range from the line of stability up to the dripline region (30-44S). For this purpose the Hartree-Fock mean field theory in coordinate space with a Skyrme parameterization SkM* has been utilized. In particular, we calculate the nuclear charge, neutrons, protons, mass densities, the associated radii, neutron skin thickness and binding energy. The charge form factors have been also investigated using SkM*, SkO, SkE, SLy4 and Skxs15 Skyrme parameterizations and the results obtained using the theoretical approach are compared with the available experimental data. To investigate the potential energy surface as a function of the quadrupole deformation for isotopic sulfur chains, Skyrme-Hartree-Fock-Bogoliubov theory has been adopted with SLy4 parameterization.
Xu, Bin; Zhang, Yanan; Jing, Zhao; Fan, Tingjun
2017-06-01
Bivalve hemoglobins have antibacterial activities, while the underlying mechanisms remain poorly understood. In our study, three full-length cDNAs of hemoglobins from blood clam skHbs were obtained, encoding putative polypeptides of 147, 150, and 152 amino acids, respectively. Predicted advanced protein structures showed that the skHbs had amphipathic antibacterial structures, displayed the typical structural characteristics of proteins with globin-like fold containing numerous alpha-helixes, and forming a homodimeric skHbI and a heterotetrameric skHbII complex. After injected with alive and heat-killed Gram-positive bacteria Bacillus subtilis, the mRNA levels of skHbI and skHbII were both significantly upregulated through increasing the expression of peptidoglycan recognition protein-like (PGRP-like) protein and Toll-like receptor (TLR-like) protein induced by peptidoglycan on the surface of the bacteria, but there were no obvious differences in their protein levels. Besides, reactive oxygen species (ROS) was detected to participate in the resistance to B. subtilis. These implied that skHbs could involve in the innate immune responses to Gram-positive bacterial infection directly with their amphipathic structures and indirectly by increasing ROS production through PGRP triggering Toll pathway. In conclusion, our findings reveal the structural characteristics of skHbs and their mechanism against Gram-positive bacteria thereby providing the molecular evidence for fundamental innate antibacterial activities by invoking respiratory proteins. Copyright © 2017 Elsevier B.V. All rights reserved.
Sekihara, Sanae; Shibata, Toshio; Hyakkendani, Mai; Kawabata, Shun-ichiro
2016-01-01
We recently reported that transglutaminase (TG) suppresses immune deficiency pathway-controlled antimicrobial peptides (IMD-AMPs), thereby conferring immune tolerance to gut microbes, and that RNAi of the TG gene in flies decreases the lifespan compared with non-TG-RNAi flies. Here, analysis of the bacterial composition of the Drosophila gut by next-generation sequencing revealed that gut microbiota comprising one dominant genus of Acetobacter in non-TG-RNAi flies was shifted to that comprising two dominant genera of Acetobacter and Providencia in TG-RNAi flies. Four bacterial strains, including Acetobacter persici SK1 and Acetobacter indonesiensis SK2, Lactobacillus pentosus SK3, and Providencia rettgeri SK4, were isolated from the midgut of TG-RNAi flies. SK1 exhibited the highest resistance to the IMD-AMPs Cecropin A1 and Diptericin among the isolated bacteria. In contrast, SK4 exhibited considerably lower resistance against Cecropin A1, whereas SK4 exhibited high resistance to hypochlorous acid. The resistance of strains SK1–4 against IMD-AMPs in in vitro assays could not explain the shift of the microbiota in the gut of TG-RNAi flies. The lifespan was reduced in gnotobiotic flies that ingested both SK4 and SK1, concomitant with the production of reactive oxygen species and apoptosis in the midgut, whereas the survival rate was not altered in gnotobiotic flies that mono-ingested either SK4 or SK1. Interestingly, significant amounts of reactive oxygen species were detected in the midgut of gnotobiotic flies that ingested SK4 and SK2, concomitant with no significant apoptosis in the midgut. In gnotobiotic flies that co-ingested SK4 and SK1, an additional unknown factor(s) may be required to cause midgut apoptosis. PMID:27760824
Reconstitution of a functional 7SK snRNP
Brogie, John E.
2017-01-01
Abstract The 7SK small nuclear ribonucleoprotein (snRNP) plays a central role in RNA polymerase II elongation control by regulating the availability of active P-TEFb. We optimized conditions for analyzing 7SK RNA by SHAPE and demonstrated a hysteretic effect of magnesium on 7SK folding dynamics including a 7SK GAUC motif switch. We also found evidence that the 5΄ end pairs alternatively with two different regions of 7SK giving rise to open and closed forms that dictate the state of the 7SK motif. We then used recombinant P-TEFb, HEXIM1, LARP7 and MEPCE to reconstruct a functional 7SK snRNP in vitro. Stably associated P-TEFb was highly inhibited, but could still be released and activated by HIV-1 Tat. Notably, P-TEFb association with both in vitro-reconstituted and cellular snRNPs led to similar changes in SHAPE reactivities, confirming that 7SK undergoes a P-TEFb-dependent structural change. We determined that the xRRM of LARP7 binds to the 3΄ stem loop of 7SK and inhibits the methyltransferase activity of MEPCE through a C-terminal MEPCE interaction domain (MID). Inhibition of MEPCE is dependent on the structure of the 3΄ stem loop and the closed form of 7SK RNA. This study provides important insights into intramolecular interactions within the 7SK snRNP. PMID:28431135
Barboric, Matjaz; Lenasi, Tina; Chen, Hui; Johansen, Eric B.; Guo, Su; Peterlin, B. Matija
2009-01-01
Eukaryotic gene expression is commonly controlled at the level of RNA polymerase II (RNAPII) pausing subsequent to transcription initiation. Transcription elongation is stimulated by the positive transcription elongation factor b (P-TEFb) kinase, which is suppressed within the 7SK small nuclear ribonucleoprotein (7SK snRNP). However, the biogenesis and functional significance of 7SK snRNP remain poorly understood. Here, we report that LARP7, BCDIN3, and the noncoding 7SK small nuclear RNA (7SK) are vital for the formation and stability of a cell stress-resistant core 7SK snRNP. Our functional studies demonstrate that 7SK snRNP is not only critical for controlling transcription elongation, but also for regulating alternative splicing of pre-mRNAs. Using a transient expression splicing assay, we find that 7SK snRNP disintegration promotes inclusion of an alternative exon via the increased occupancy of P-TEFb, Ser2-phosphorylated (Ser2-P) RNAPII, and the splicing factor SF2/ASF at the minigene. Importantly, knockdown of larp7 or bcdin3 orthologues in zebrafish embryos destabilizes 7SK and causes severe developmental defects and aberrant splicing of analyzed transcripts. These findings reveal a key role for P-TEFb in coupling transcription elongation with alternative splicing, and suggest that maintaining core 7SK snRNP is essential for vertebrate development. PMID:19416841
Strategies for Strengthening Women's Participation in Trade Union Leadership.
ERIC Educational Resources Information Center
Trebilcock, Anne
1991-01-01
Union efforts to increase representation of women in leadership include (1) strong policy commitment; (2) identification of factors/barriers affecting women's leadership; (3) intensified training; and (4) organizational/structural changes such as alteration of rules and adoption of quotas. (SK)
SK4 channels modulate Ca2+ signalling and cell cycle progression in murine breast cancer.
Steudel, Friederike A; Mohr, Corinna J; Stegen, Benjamin; Nguyen, Hoang Y; Barnert, Andrea; Steinle, Marc; Beer-Hammer, Sandra; Koch, Pierre; Lo, Wing-Yee; Schroth, Werner; Hoppe, Reiner; Brauch, Hiltrud; Ruth, Peter; Huber, Stephan M; Lukowski, Robert
2017-09-01
Oncogenic signalling via Ca 2+ -activated K + channels of intermediate conductance (SK4, also known as K Ca 3.1 or IK) has been implicated in different cancer entities including breast cancer. Yet, the role of endogenous SK4 channels for tumorigenesis is unclear. Herein, we generated SK4-negative tumours by crossing SK4-deficient (SK4 KO) mice to the polyoma middle T-antigen (PyMT) and epidermal growth factor receptor 2 (cNeu) breast cancer models in which oncogene expression is driven by the retroviral promoter MMTV. Survival parameters and tumour progression were studied in cancer-prone SK4 KO in comparison with wild-type (WT) mice and in a syngeneic orthotopic mouse model following transplantation of SK4-negative or WT tumour cells. SK4 activity was modulated by genetic or pharmacological means using the SK4 inhibitor TRAM-34 in order to establish the role of breast tumour SK4 for cell growth, electrophysiological signalling, and [Ca 2+ ] i oscillations. Ablation of SK4 and TRAM-34 treatment reduced the SK4-generated current fraction, growth factor-dependent Ca 2+ entry, cell cycle progression and the proliferation rate of MMTV-PyMT tumour cells. In vivo, PyMT oncogene-driven tumorigenesis was only marginally affected by the global lack of SK4, whereas tumour progression was significantly delayed after orthotopic implantation of MMTV-PyMT SK4 KO breast tumour cells. However, overall survival and progression-free survival time in the MMTV-cNeu mouse model were significantly extended in the absence of SK4. Collectively, our data from murine breast cancer models indicate that SK4 activity is crucial for cell cycle control. Thus, the modulation of this channel should be further investigated towards a potential improvement of existing antitumour strategies in human breast cancer. © 2017 The Authors. Published by FEBS Press and John Wiley & Sons Ltd.
Influence of the Family in Career Decision-Making.
ERIC Educational Resources Information Center
Chope, Robert C.
2001-01-01
Two recently emerging factors are changing the role of family in career decision making: the revolutionary changes in family structure and increased emphasis on interpersonal relationships in work. Career counselors need new protocols in order to work with clients and family members. (SK)
The Cytoplasmic Adaptor Protein Dok7 Activates the Receptor Tyrosine Kinase MuSK via Dimerization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bergamin, E.; Hallock, P; Burden, S
Formation of the vertebrate neuromuscular junction requires, among others proteins, Agrin, a neuronally derived ligand, and the following muscle proteins: LRP4, the receptor for Agrin; MuSK, a receptor tyrosine kinase (RTK); and Dok7 (or Dok-7), a cytoplasmic adaptor protein. Dok7 comprises a pleckstrin-homology (PH) domain, a phosphotyrosine-binding (PTB) domain, and C-terminal sites of tyrosine phosphorylation. Unique among adaptor proteins recruited to RTKs, Dok7 is not only a substrate of MuSK, but also an activator of MuSK's kinase activity. Here, we present the crystal structure of the Dok7 PH-PTB domains in complex with a phosphopeptide representing the Dok7-binding site on MuSK.more » The structure and biochemical data reveal a dimeric arrangement of Dok7 PH-PTB that facilitates trans-autophosphorylation of the kinase activation loop. The structure provides the molecular basis for MuSK activation by Dok7 and for rationalizing several Dok7 loss-of-function mutations found in patients with congenital myasthenic syndromes.« less
Mitochondria-targeted antioxidant SkQ1 improves impaired dermal wound healing in old mice.
Demyanenko, Ilya A; Popova, Ekaterina N; Zakharova, Vlada V; Ilyinskaya, Olga P; Vasilieva, Tamara V; Romashchenko, Valeria P; Fedorov, Artem V; Manskikh, Vasily N; Skulachev, Maxim V; Zinovkin, Roman A; Pletjushkina, Olga Yu; Skulachev, Vladimir P; Chernyak, Boris V
2015-07-01
The process of skin wound healing is delayed or impaired in aging animals. To investigate the possible role of mitochondrial reactive oxygen species (mtROS) in cutaneous wound healing of aged mice, we have applied the mitochondria-targeted antioxidant SkQ1. The SkQ1 treatment resulted in accelerated resolution of the inflammatory phase, formation of granulation tissue, vascularization and epithelization of the wounds. The wounds of SkQ1-treated mice contained increased amount of myofibroblasts which produce extracellular matrix proteins and growth factors mediating granulation tissue formation. This effect resembled SkQ1-induced differentiation of fibroblasts to myofibroblast, observed earlierin vitro. The Transforming Growth Factor beta (TGFb) produced by SkQ1-treated fibroblasts was found to stimulated motility of endothelial cells in vitro, an effect which may underlie pro-angiogenic action of SkQ1 in the wounds. In vitro experiments showed that SkQ1 prevented decomposition of VE-cadherin containing contacts and following increase in permeability of endothelial cells monolayer, induced by pro-inflammatory cytokine TNF. Prevention of excessive reaction of endothelium to the pro-inflammatory cytokine(s) might account for anti-inflammatory effect of SkQ1. Our findings point to an important role of mtROS in pathogenesis of age-related chronic wounds.
Mitochondria-targeted antioxidant SkQ1 improves impaired dermal wound healing in old mice
Zakharova, Vlada V.; Ilyinskaya, Olga P.; Vasilieva, Tamara V.; Romashchenko, Valeria P.; Fedorov, Artem V.; Manskikh, Vasily N.; Skulachev, Maxim V.; Zinovkin, Roman A.; Pletjushkina, Olga Yu.; Skulachev, Vladimir P.; Chernyak, Boris V.
2015-01-01
The process of skin wound healing is delayed or impaired in aging animals. To investigate the possible role of mitochondrial reactive oxygen species (mtROS) in cutaneous wound healing of aged mice, we have applied the mitochondria-targeted antioxidant SkQ1. The SkQ1 treatment resulted in accelerated resolution of the inflammatory phase, formation of granulation tissue, vascularization and epithelization of the wounds. The wounds of SkQ1-treated mice contained increased amount of myofibroblasts which produce extracellular matrix proteins and growth factors mediating granulation tissue formation. This effect resembled SkQ1-induced differentiation of fibroblasts to myofibroblast, observed earlier in vitro. The Transforming Growth Factor beta (TGFβ)produced by SkQ1-treated fibroblasts was found to stimulated motility of endothelial cells in vitro, an effect which may underlie pro-angiogenic action of SkQ1 in the wounds. In vitro experiments showed that SkQ1 prevented decomposition of VE-cadherin containing contacts and following increase in permeability of endothelial cells monolayer, induced by pro-inflammatory cytokine TNF. Prevention of excessive reaction of endothelium to the pro-inflammatory cytokine(s) might account for anti-inflammatory effect of SkQ1. Our findings point to an important role of mtROS in pathogenesis of age-related chronic wounds. PMID:26187706
Kazemi, Faegheh; Arab, Seyed Shahriar; Mohajel, Nasir; Keramati, Malihe; Niknam, Niloofar; Aslani, Mohammad Mehdi; Roohvand, Farzin
2018-05-28
Streptokinase (SK), a plasminogen activator (PA) that converts inactive plasminogen (Pg) to plasmin (Pm), is a protein secreted by groups A, C, and G streptococci (GAS, GCS, and GGS, respectively), with high sequence divergence and functional heterogeneity. While roles of some residual changes in altered SK functionality are shown, the underlying structural mechanisms are less known. Herein, using computational approaches, we analyzed the conformational basis for the increased activity of SK from a GGS (SKG132) isolate with four natural residual substitutions (Ile33Phe, Arg45Gln, Asn228Lys, Phe287Ile) compared to the standard GCS (SKC). Using the crystal structure of SK.Pm catalytic complex as main template SKC.μPm catalytic complex was modeled through homology modeling process and validated by several online validation servers. Subsequently, SKG132.μPm structure was constructed by altering the corresponding residual substitutions. Results of three independent MD simulations showed increased RMSF values for SKG132.μPm, indicating the enhanced structural flexibility compared to SKC.μPm, specially in 170 and 250 loops and three regions: R1 (149-161), R2 (182-215) and R3 (224-229). In parallel, the average number of Hydrogen bonds in 170 loop, R2 and R3 (especially for Asn228Lys) of SKG132 compared to that of the SKC was decreased. Accordingly, residue interaction networks (RINs) analyses indicated that Asn228Lys might induce more level of structural flexibility by generation of free Lys256, while Phe287Ile and Ile33Phe enhanced the stabilization of the SKG132.μPm catalytic complex. These results denoted the potential role of the optimal dynamic state and stabilized catalytic complex for increased PA potencies of SK as a thrombolytic drug.
Taub, Pam R.; Ramirez‐Sanchez, Israel; Ciaraldi, Theodore P.; Perkins, Guy; Murphy, Anne N.; Naviaux, Robert; Hogan, Michael; Maisel, Alan S.; Henry, Robert R.; Ceballos, Guillermo
2012-01-01
Abstract (‐)‐Epicatechin (Epi), a flavanol in cacao stimulates mitochondrial volume and cristae density and protein markers of skeletal muscle (SkM) mitochondrial biogenesis in mice. Type 2 diabetes mellitus (DM2) and heart failure (HF) are diseases associated with defects in SkM mitochondrial structure/function. A study was implemented to assess perturbations and to determine the effects of Epi‐rich cocoa in SkM mitochondrial structure and mediators of biogenesis. Five patients with DM2 and stage II/III HF consumed dark chocolate and a beverage containing approximately 100 mg of Epi per day for 3 months. We assessed changes in protein and/or activity levels of oxidative phosphorylation proteins, porin, mitofilin, nNOS, nitric oxide, cGMP, SIRT1, PGC1α, Tfam, and mitochondria volume and cristae abundance by electron microscopy from SkM. Apparent major losses in normal mitochondria structure were observed before treatment. Epi‐rich cocoa increased protein and/or activity of mediators of biogenesis and cristae abundance while not changing mitochondrial volume density. Epi‐rich cocoa treatment improves SkM mitochondrial structure and in an orchestrated manner, increases molecular markers of mitochondrial biogenesis resulting in enhanced cristae density. Future controlled studies are warranted using Epi‐rich cocoa (or pure Epi) to translate improved mitochondrial structure into enhanced cardiac and/or SkM muscle function. Clin Trans Sci 2012; Volume 5: 43–47 PMID:22376256
Ou, Judy J. J.; Drilling, Amanda J.; Cooksley, Clare; Bassiouni, Ahmed; Kidd, Stephen P.; Psaltis, Alkis J.; Wormald, Peter J.; Vreugde, Sarah
2016-01-01
Background: Staphylococcus aureus (S. aureus) small colony variants (SCVs) can survive within the host intracellular milieu and are associated with chronic relapsing infections. However, it is unknown whether host invasion rates and immune responses differ between SCVs and their wild-type counterparts. This study used a stable S. aureus SCV (WCH-SK2SCV) developed from a clinical isolate (WCH-SK2WT) in inflammation-relevant conditions. Intracellular infection rates as well as host immune responses to WCH-SK2WT and WCH-SK2SCV infections were investigated. Method: NuLi-1 cells were infected with either WCH-SK2WT or WCH-SK2SCV, and the intracellular infection rate was determined over time. mRNA expression of cells infected with each strain intra- and extra-cellularly was analyzed using a microfluidic qPCR array to generate an expression profile of thirty-nine genes involved in the host immune response. Results: No difference was found in the intracellular infection rate between WCH-SK2WT and WCH-SK2SCV. Whereas, extracellular infection induced a robust pro-inflammatory response, intracellular infection elicited a modest response. Intracellular WCH-SK2WT infection induced mRNA expression of TLR2, pro-inflammatory cytokines (IL1B, IL6, and IL12) and tissue remodeling factors (MMP9). In contrast, intracellular WCH-SK2SCV infection induced up regulation of only TLR2. Conclusions: Whereas, host intracellular infection rates of WCH-SK2SCV and WCH-SK2WT were similar, WCH-SK2SCV intracellular infection induced a less widespread up regulation of pro-inflammatory and tissue remodeling factors in comparison to intracellular WCH-SK2WT infection. These findings support the current view that SCVs are able to evade host immune detection to allow their own survival. PMID:28083514
Cescutti, P; Ravenscroft, N; Ng, S; Lam, Z; Dutton, G G
1993-06-21
The capsular polysaccharide of Klebsiella SK1 was investigated by methylation analysis, Smith degradation, and 1H NMR spectroscopy. The oligosaccharides (P1 and P2) obtained by bacteriophage phi SK1 degradation of the polymer were studied by methylation analysis, and 1D- and 2D-NMR spectroscopy. The resulting data showed that the parent repeating unit is a branched pentasaccharide having a structure identical to the revised structure recently proposed for Klebsiella serotype K8 capsular polysaccharide. [Formula: see text] The 2D-NMR data showed that one third of the glucuronic acid residues in the SK1 polymer are acetylated at O-2, O-3, or O-4. FABMS studies confirmed the presence of monoacetylated glucuronic acid residues. Thus, the relationship between the Klebsiella K8 and SK1 polymers is akin to that found for Klebsiella polysaccharides K30 and K33, which have been typed as serologically distinct yet their structures differ only in the degree of acetylation.
[Roles of KLF5 in inhibition TNFα-induced SK-BR-3 breast cancer cell apoptosis].
Shi, Jianhong; Liu, Caiyun; Zhang, Anyi; Cui, Naipeng; Wang, Bing; Chen, Baoping; Ma, Zhenfeng
2014-07-08
To explore the expression levels and roles of Krüpple-like factor 5 (KLF5) in tumor necrosis factor α (TNFα)-induced SK-BR-3 breast cancer cells. SK-BR-3 breast cancer cells were stimulated by TNFα at different concentrations (0, 1, 5, 10, 20 µg/L) for specified durations (0, 6, 12, 24, 36 h). Western blot was performed to detect KLF5 protein levels. Then Western blot and quantitative real-time PCR (qRT-PCR) were used to detect the expression levels of apoptosis genes. Flow cytometry and qRT-PCR were used to observe the effects of exogenous KLF5 on TNFα-induced apoptosis of SK-BR-3 breast cancer cell. KLF5 expression levels significantly decreased in TNFα-stimulated SK-BR-3 breast cancer cells in a concentration- and time-dependent manner. Quantitative RT-PCR results showed that TNFα up-regulate apoptosis gene caspase 3, caspase 9 and bax expression levels and down-regulate bcl-1 level in SK-BR-3 cells. Adenovirus expression vectors of pAd-GFP and pAd-GFP-KLF5 were constructed and used to infect SK-BR-3 breast cancer cells. Over-expression of GFP-KLF5 inhibited apoptosis in TNFα-stimulated SK-BR-3 breast cancer cells. TNFα reduces KLF5 expression in SK-BR-3 breast cancer cells and KLF5 participates in TNFα-induced SK-BR-3 cell apoptosis.
7SK-BAF axis controls pervasive transcription at enhancers
Flynn, Ryan A.; Do, Brian T.; Rubin, Adam J.; Calo, Eliezer; Lee, Byron; Kuchelmeister, Hannes; Rale, Michael; Chu, Ci; Kool, Eric T.; Wysocka, Joanna; Khavari, Paul A.
2016-01-01
RNA functions at enhancers remain mysterious. Here we show that the 7SK small nuclear RNA (snRNA) inhibits enhancer transcription by modulating nucleosome position. 7SK occupies enhancers and super enhancers genome-wide in mouse and human cells, and 7SK is required to limit eRNA initiation and synthesis in a manner distinct from promoter pausing. Clustered elements at super enhancers uniquely require 7SK to prevent convergent transcription and DNA damage signaling. 7SK physically interacts with the BAF chromatin remodeling complex, recruit BAF to enhancers, and inhibits enhancer transcription by modulating chromatin structure. In turn, 7SK occupancy at enhancers coincides with Brd4 and is exquisitely sensitive to the bromodomain inhibitor JQ1. Thus, 7SK employs distinct mechanisms to counteract diverse consequences of pervasive transcription that distinguish super enhancers, enhancers, and promoters. PMID:26878240
USDA-ARS?s Scientific Manuscript database
Sulfakinin (SK) is a sulfated insect neuropeptide that is best known for its function as a satiety factor. It displays structural and functional similarities with the vertebrate peptides gastrin and cholecystokinin. Peptidomic studies in multiple insects, crustaceans and arachnids have revealed th...
MuSK IgG4 autoantibodies cause myasthenia gravis by inhibiting binding between MuSK and Lrp4
Huijbers, Maartje G.; Zhang, Wei; Klooster, Rinse; Niks, Erik H.; Friese, Matthew B.; Straasheijm, Kirsten R.; Thijssen, Peter E.; Vrolijk, Hans; Plomp, Jaap J.; Vogels, Pauline; Losen, Mario; Van der Maarel, Silvère M.; Burden, Steven J.; Verschuuren, Jan J.
2013-01-01
Myasthenia gravis (MG) is a severely debilitating autoimmune disease that is due to a decrease in the efficiency of synaptic transmission at neuromuscular synapses. MG is caused by antibodies against postsynaptic proteins, including (i) acetylcholine receptors, the neurotransmitter receptor, (ii) muscle-specific kinase (MuSK), a receptor tyrosine kinase essential for the formation and maintenance of neuromuscular synapses, and (iii) low-density lipoprotein receptor-related protein 4 (Lrp4), which responds to neural Agrin by binding and stimulating MuSK. Passive transfer studies in mice have shown that IgG4 antibodies from MuSK MG patients cause disease without requiring complement or other immune components, suggesting that these MuSK antibodies cause disease by directly interfering with MuSK function. Here we show that pathogenic IgG4 antibodies to MuSK bind to a structural epitope in the first Ig-like domain of MuSK, prevent binding between MuSK and Lrp4, and inhibit Agrin-stimulated MuSK phosphorylation. In contrast, these IgG4 antibodies have no direct effect on MuSK dimerization or MuSK internalization. These results provide insight into the unique pathogenesis of MuSK MG and provide clues toward development of specific treatment options. PMID:24297891
The 7SK snRNP associates with the little elongation complex to promote snRNA gene expression.
Egloff, Sylvain; Vitali, Patrice; Tellier, Michael; Raffel, Raoul; Murphy, Shona; Kiss, Tamás
2017-04-03
The 7SK small nuclear RNP (snRNP), composed of the 7SK small nuclear RNA (snRNA), MePCE, and Larp7, regulates the mRNA elongation capacity of RNA polymerase II (RNAPII) through controlling the nuclear activity of positive transcription elongation factor b (P-TEFb). Here, we demonstrate that the human 7SK snRNP also functions as a canonical transcription factor that, in collaboration with the little elongation complex (LEC) comprising ELL, Ice1, Ice2, and ZC3H8, promotes transcription of RNAPII-specific spliceosomal snRNA and small nucleolar RNA (snoRNA) genes. The 7SK snRNA specifically associates with a fraction of RNAPII hyperphosphorylated at Ser5 and Ser7, which is a hallmark of RNAPII engaged in snRNA synthesis. Chromatin immunoprecipitation (ChIP) and chromatin isolation by RNA purification (ChIRP) experiments revealed enrichments for all components of the 7SK snRNP on RNAPII-specific sn/snoRNA genes. Depletion of 7SK snRNA or Larp7 disrupts LEC integrity, inhibits RNAPII recruitment to RNAPII-specific sn/snoRNA genes, and reduces nascent snRNA and snoRNA synthesis. Thus, through controlling both mRNA elongation and sn/snoRNA synthesis, the 7SK snRNP is a key regulator of nuclear RNA production by RNAPII. © 2017 The Authors.
ERIC Educational Resources Information Center
Sagiv, Lilach
1999-01-01
A taxonomy of decision behavior styles (independence/dependence, active/passive, insightful/not) tested with 372 career counseling clients was supported by similar structure analysis and confirmatory factor analysis. Counselors were more likely to be satisfied with decisions of clients they perceived to be insightful. (SK)
Blueprint for the Assessment of Socio-Structural Influences in Career Choice and Decision Making.
ERIC Educational Resources Information Center
Brown, Michael T.
2000-01-01
In the context of societal racism, sexism, and classism, career assessment of women and minority groups should take into account sociostructural realities and their psychological effects. Factors include the objective and subjective realities of the economic, social status, and social power domains. (Contains 33 references.) (SK)
Multivariable frequency domain identification via 2-norm minimization
NASA Technical Reports Server (NTRS)
Bayard, David S.
1992-01-01
The author develops a computational approach to multivariable frequency domain identification, based on 2-norm minimization. In particular, a Gauss-Newton (GN) iteration is developed to minimize the 2-norm of the error between frequency domain data and a matrix fraction transfer function estimate. To improve the global performance of the optimization algorithm, the GN iteration is initialized using the solution to a particular sequentially reweighted least squares problem, denoted as the SK iteration. The least squares problems which arise from both the SK and GN iterations are shown to involve sparse matrices with identical block structure. A sparse matrix QR factorization method is developed to exploit the special block structure, and to efficiently compute the least squares solution. A numerical example involving the identification of a multiple-input multiple-output (MIMO) plant having 286 unknown parameters is given to illustrate the effectiveness of the algorithm.
Formigli, L; Zecchi-Orlandini, S; Meacci, E; Bani, D
2010-01-01
Until recently, skeletal myoblasts (SkMBs) have been the most widely used cells in basic research and clinical trials of cell based therapy for cardiac repair and regeneration. Although SkMB engraftment into the post-infarcted heart has been consistently found to improve cardiac contractile function, the underlying therapeutic mechanisms remain still a matter of controversy and debate. This is basically because SkMBs do not attain a cardiac-like phenotype once homed into the diseased heart nor they form a contractile tissue functionally coupled with the surrounding viable myocardium. This issue of concern has generated the idea that the cardiotropic action of SkMBs may depend on the release of paracrine factors. However, the paracrine hypothesis still remains ill-defined, particularly concerning the identification of the whole spectrum of cell-derived soluble factors and details on their cardiac effects. In this context, the possibility to genetically engineering SkMBs to potentate their paracrine attitudes appears particularly attractive and is actually raising great expectation. Aim of the present review is not to cover all the aspects of cell-based therapy with SkMBs, as this has been the object of previous exhaustive reviews in this field. Rather, we focused on novel aspects underlying the interactions between SkMBs and the host cardiac tissues which may be relevant for directing the future basic and applied research on SkMB transplantation for post ischemic cardiac dysfunction.
Orgilés, Mireia; Morales, Alexandra; Fernández-Martínez, Iván; Melero, Silvia; Espada, José P
2018-01-01
This study aimed to validate a short version of the Cognitive Emotion Regulation Questionnaire for Spanish kids (CERQ-Sk) based on the 18-item version available for adults. A sample of 654 children aged 7-12 years completed the CERQ-Sk and tests for depression and anxiety measures. Confirmatory factor analysis supported the 18-item version and the original nine-factor structure, which includes self-blame, acceptance, rumination, positive refocusing, refocus on planning, positive reappraisal, putting into perspective, catastrophizing, and other-blame (comparative fit index = .99, Tucker-Lewis index = .98, root mean square error of approximation = .02). Internal consistency was adequate (ordinal α = .80), and the eight-week stability of this version was moderate (intraclass correlation = .69). Criterion validity was supported by correlations among self-blame, rumination, and catastrophizing (positive) and among positive reappraisal and depression and anxiety symptoms (negative). Results suggest that the short version of the CERQ-Sk is a valid and reliable instrument for assessing these cognitive emotion regulation strategies during the middle childhood developmental period. Clinicians and researchers will benefit from this briefer acceptable version when time is not available for the 36-item version. This study offers preliminary results for the first short version of the CERQ for children.
ERIC Educational Resources Information Center
Davis, Paul; Kvern, Brent; Donen, Neil; Andrews, Elaine; Nixon, Olga
2000-01-01
Pre/posttest data on 40 physicians who completed problem-based clinical scenarios on osteoporosis revealed that 39 showed improvement or modest change in postworkshop scores, especially in terms of management of male patients, determination of risk factors, and use and interpretation of bone density tests. (SK)
Shi, Xiaolei; Peng, Yonghan; Li, Ling; Li, Xiao; Wang, Qi; Zhang, Wei; Dong, Hao; Shen, Rong; Lu, Chaoyue; Liu, Min; Gao, Xiaofeng; Sun, Yinghao
2018-05-26
To evaluate renal function changes and risk factors for acute kidney injury (AKI) after percutaneous nephrolithotomy (PCNL) in patients with renal calculi with a solitary kidney (SK) or normal bilateral kidneys (BKs). Between 2012 and 2016, 859 patients undergoing PCNL were retrospectively reviewed at Changhai Hospital. In all, 53 patients with a SK were paired with 53 patients with normal BKs via a propensity score-matched analysis. Data for the following variables were collected: age, sex, body mass index, stone size, distribution, operation time, perioperative outcomes, and complications. The complications were graded according to the modified Clavien-Dindo system. Univariable and multivariable logistic regression models were constructed to evaluate risk factors for predicting AKI. The SK and BKs groups were comparable in terms of age, sex ratio, stone size, stone location distribution, comorbidities, and American Society of Anesthesiologists Physical Status classification. The initial and final stone-free rates were comparable between the SK and BKs groups (initial: 52.83% vs 58.49%, P = 0.696; final: 84.91% vs 92.45%, P = 0.359). There was no difference between the two groups for complications, according to the Clavien-Dindo grades. The estimated glomerular filtration rate (eGFR) increased dramatically after the stone burden was immediately relieved, and during the 6-month follow-up eGFR was lower in the SK group compared with the BKs group. We found a modest improvement in renal function immediately after PCNL in the BKs group, and renal function gain was delayed in the SK group. Through logistic regression analysis, we discovered that a SK, preoperative creatinine and diabetes were independent risk factors for predicting AKI after PCNL. Considering the overall complication rates, PCNL is generally a safe procedure for treating renal calculi amongst patients with a SK or normal BKs. Follow-up renal function analysis showed a modest improvement in patients of both groups. Compared to patients with normal BKs, patients with a SK were more likely to develop AKI after PCNL. © 2018 The Authors BJU International © 2018 BJU International Published by John Wiley & Sons Ltd.
Park, Sang Won; Kim, Mihwa; Kim, Joo Yun; Brown, Kevin M.; Haase, Volker H.; D’Agati, Vivette D.; Lee, H. Thomas
2012-01-01
Renal ischemia reperfusion injury is a major cause of acute kidney injury. We previously found that renal A1 adenosine receptor (A1AR) activation attenuated multiple cell death pathways including necrosis, apoptosis and inflammation. Here, we tested whether induction of cytoprotective sphingosine kinase (SK)-1 and sphingosine-1 phosphate (S1P) synthesis might be the mechanism of protection. A selective A1AR agonist (CCPA) increased the synthesis of S1P and selectively induced SK-1 in mouse kidney and HK-2 cells. This agonist failed to protect SK1-knockout but protected SK2-knockout mice against renal ischemia reperfusion injury indicating a critical role of SK1 in A1AR-mediated renal protection. Inhibition of SK prevented A1AR-mediated defense against necrosis and apoptosis in HK-2 cells. A selective S1P1R antagonist (W146) and global in vivo gene knockdown of S1P1Rs with small interfering RNA completely abolished the renal protection provided by CCPA. Mice selectively deficient in renal proximal tubule S1P1Rs (S1P1Rflox/flox PEPCKCre/−) were not protected against renal ischemia reperfusion injury by CCPA. Mechanistically, CCPA increased nuclear translocation of hypoxia inducible factor-1α in HK-2 cells and selective hypoxia inducible factor-1α inhibition blocked A1AR-mediated induction of SK1. Thus, proximal tubule SK-1 has a critical role in A1AR-mediated protection against renal ischemia reperfusion injury. PMID:22695326
Dermoscopy-pathology relationship in seborrheic keratosis.
Minagawa, Akane
2017-05-01
Making a definitive diagnosis of seborrheic keratosis (SK) can be challenging for the naked eye due to its wide variation in clinical features. Fortunately, however, most cases of SK exhibit the typical dermoscopic findings of fissures and ridges, hairpin vessels with white halo, comedo-like openings, and milia-like cysts, all of which are helpful to distinguish SK from melanoma, melanocytic nevus, squamous cell carcinoma, basal cell carcinoma (BCC) and other skin tumors. Histopathologically, these dermoscopic characteristics correspond to papillomatous surface of the epidermis, enlarged capillaries of the dermal papillae, pseudohorn cysts in the epidermis opened to the surface of the lesion and intraepidermal cysts, respectively. Clinicians should bear in mind that the clonal type of SK dermoscopically mimics melanoma and BCC by the presence of globule-like structures, while regressing SK exhibits a granular pattern that is similar to the peppering found in melanoma. Furthermore, milia-like cysts alone are insufficient for a conclusive diagnosis of SK because melanoma in rare cases displays cysts along with other SK-like dermoscopic findings. © 2017 Japanese Dermatological Association.
Vasanthi, A. Hannah Rachel; Muthulakshmi, V.; Gayathri, V.; Manikandan, R.; Ananthi, S.; Kuruvilla, Sarah
2017-01-01
Background: Sirupeelai Samoola Kudineer (SK), a polyherbal decoction containing four medicinal plants has been used in Siddha system of medicine, practiced in Southern parts of India for the management of urolithiasis. Objective: The present study is carried out to scientifically validate the traditional claim and to study the mechanism of action of the drug. Materials and Methods: In the present study, anti-urolithiatic effect of SK was evaluated in Sprague-Dawley rats using ethylene glycol through drinking water and intraperitoneal injection of sodium oxalate. Renal damage was confirmed by the increased production of thiobarbituric acid reactive substance (TBARS). Results: Co-treatment with SK to urolithiatic rats for 21 days significantly prevented the elevation of renal and urinary stone biomarkers in plasma and renal tissue thereby preventing renal damage and the formation of renal calculi. Administration of SK at all doses and cystone restored the antioxidant (glutathione) levels by preventing the elevation of TBARS in the kidney tissue, which was further confirmed by histological sections. Conclusions: SK treatment promotes diuresis which leads to flushing of the renal stones and maintains the alkaline environment in the urinary system which probably mediates the antilithiatic activity. SK provides structural and functional protection to the kidneys by enhancing its physiological function against stone formation and validates its clinical use. SUMMARY SK exhibited antilithiatic and diuretic potential in ethylene glycol and sodium oxalate induced urolithiasis in ratsElevated urinary stone markers (Calcium, oxalate, uric acid, magnesium and phosphates) in plasma and renal tubular enzymes (LDH, GGT, ALP, AST ALT) in urolithiatic rats were reversed by SK treatmentSK administration significantly reduced the level of renal stress markers like Urea, Creatinine, LPO and elevated SOD, GPx, GSH levels aiding in nephroprotectionSK also provides structural and functional protection against ethylene glycol- induced renal calculus in rats as evidenced by histopathological studies. Abbreviations used: SK: Sirupeelai Samoola Kudineer; TBARS: ThioBarbituric Acid Reactive Substances; SOD: SuperOxide Dismutase; GPx: Gluthathione peroxidase; GSH- Glutathione; LPO: Lipid peroxidation as measured as TBARS; AST: Aspartate AminoTransferase; ALT: Alanine Amino transferase; GGT: Gamma Glutamyl Transferase; LDH: Lactate Dehydrogenase. PMID:28808392
Shi, Jian-Hong; Cui, Nai-Peng; Wang, Shuo; Zhao, Ming-Zhi; Wang, Bing; Wang, Ya-Nan; Chen, Bao-Ping
2016-01-01
Y-box-binding protein 1 (YB1) is a multifunctional transcription factor with vital roles in proliferation, differentiation and apoptosis. In this study, we have examined the role of its C-terminal domain (YB1 CTD) in proliferation, angiogenesis and tumorigenicity in breast cancer. Breast cancer cell line SK-BR-3 was infected with GFP-tagged YB1 CTD adenovirus expression vector. An 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) proliferation assay showed that YB1 CTD decreased SK-BR-3 cell proliferation, and down-regulated cyclin B1 and up-regulated p21 levels in SK-BR-3 cells. YB1 CTD overexpression changed the cytoskeletal organization and slightly inhibited the migration of SK-BR-3 cells. YB1 CTD also inhibited secreted VEGF expression in SK-BR-3 cells, which decreased SK-BR-3-induced EA.hy926 endothelial cell angiogenesis in vitro. YB1 CTD overexpression attenuated the ability of SK-BR-3 cells to form tumours in nude mice, and decreased in vivo VEGF levels and angiogenesis in the xenografts in SK-BR-3 tumour-bearing mice. Taken together, our findings demonstrate the vital role of YB1 CTD overexpression in inhibiting proliferation, angiogenesis and tumorigenicity of breast cancer cell line SK-BR-3.
Air-kerma strength determination of a new directional 103Pd source
Reed, Joshua L.; DeWerd, Larry A.; Culberson, Wesley S.
2015-01-01
Purpose: A new directional 103Pd planar source array called a CivaSheet™ has been developed by CivaTech Oncology, Inc., for potential use in low-dose-rate (LDR) brachytherapy treatments. The array consists of multiple individual polymer capsules called CivaDots, containing 103Pd and a gold shield that attenuates the radiation on one side, thus defining a hot and cold side. This novel source requires new methods to establish a source strength metric. The presence of gold material in such close proximity to the active 103Pd region causes the source spectrum to be significantly different than the energy spectra of seeds normally used in LDR brachytherapy treatments. In this investigation, the authors perform air-kerma strength (SK) measurements, develop new correction factors for these measurements based on an experimentally verified energy spectrum, and test the robustness of transferring SK to a well-type ionization chamber. Methods: SK measurements were performed with the variable-aperture free-air chamber (VAFAC) at the University of Wisconsin Medical Radiation Research Center. Subsequent measurements were then performed in a well-type ionization chamber. To realize the quantity SK from a directional source with gold material present, new methods and correction factors were considered. Updated correction factors were calculated using the mcnp 6 Monte Carlo code in order to determine SK with the presence of gold fluorescent energy lines. In addition to SK measurements, a low-energy high-purity germanium (HPGe) detector was used to experimentally verify the calculated spectrum, a sodium iodide (NaI) scintillating counter was used to verify the azimuthal and polar anisotropy, and a well-type ionization chamber was used to test the feasibility of disseminating SK values for a directional source within a cylindrically symmetric measurement volume. Results: The UW VAFAC was successfully used to measure the SK of four CivaDots with reproducibilities within 0.3%. Monte Carlo methods were used to calculate the UW VAFAC correction factors and the calculated spectrum emitted from a CivaDot was experimentally verified with HPGe detector measurements. The well-type ionization chamber showed minimal variation in response (<1.5%) as a function of source positioning angle, indicating that an American Association of Physicists in Medicine (AAPM) Accredited Dosimetry Calibration Laboratory calibrated well chamber would be a suitable device to transfer an SK-based calibration to a clinical user. SK per well-chamber ionization current ratios were consistent among the four dots measured. Additionally, the measurements and predictions of anisotropy show uniform emission within the solid angle of the VAFAC, which demonstrates the robustness of the SK measurement approach. Conclusions: This characterization of a new 103Pd directional brachytherapy source helps to establish calibration methods that could ultimately be used in the well-established AAPM Task Group 43 formalism. Monte Carlo methods accurately predict the changes in the energy spectrum caused by the fluorescent x-rays produced in the gold shield. PMID:26632069
NASA Astrophysics Data System (ADS)
Yang, Xiyan; Wu, Yahao; Yuan, Zhanjiang
2015-06-01
Two-component signaling modules exist extensively in bacteria and microbes. These modules can be, based on their distinct network structures, divided into two types: the monofunctional system (denoted by MFS) where the sensor kinase (SK) modulates only phosphorylation of the response regulator (RR), and the bifunctional system (denoted by BFS) where the SK catalyzes both phosphorylation and dephosphorylation of the RR. Here, we analyze dynamical behaviors of these two systems based on stability theory, focusing on differences between them. The analysis of the deterministic behavior indicates that there is no difference between the two modules, that is, each system has the unique stable steady state. However, there are significant differences in stochastic behavior between them. Specifically, if the mean phosphorylated SK level is kept the same for the two modules, then the variance and the Fano factor for the phosphorylated RR in the BFS are always no less than those in the MFS, indicating that bifunctionality always enhances fluctuations. The correlation between the phosphorylated SK and the phosphorylated RR in the BFS is always positive mainly due to competition between system components, but this correlation in the MFS may be positive, almost zero, or negative, depending on the ratio between two rate constants. Our overall analysis indicates that differences between dynamical behaviors of monofunctional and bifunctional signaling modules are mainly in the stochastic rather than deterministic aspect.
Raju, N. B.; Perkins, D. D.
1991-01-01
It was shown previously that when a chromosomal Spore killer factor is heterozygous in Neurospora species with eight-spored asci, the four sensitive ascospores in each ascus die and the four survivors are all killers. Sk-2(K) and Sk-3(K) are nonrecombining haplotypes that segregate with the centromere of linkage group III. No killing occurs when either one of these killers is homozygous, but each is sensitive to killing by the other in crosses of Sk-2(K) X Sk-3(K). In the present study, Sk-2(K) and Sk-3(K) were transferred by recurrent backcrosses from the eight-spored species Neurospora crassa into Neurospora tetrasperma, a pseudohomothallic species which normally makes asci with four large spores, each heterokaryotic for mating type and for any other centromere-linked genes that are heterozygous in the cross. The action of Sk-2(K) and Sk-3(K) in N. tetrasperma is that predicted from their behavior in eight-spored species. A sensitive nucleus is protected from killing if it is enclosed in the same ascospore with a killer nucleus. Crosses of Sk-2(K) X Sk-2(S), Sk-3(K) X Sk-3(S), and Sk-2(K) X Sk-3(K) all produce four-spored asci that are wild type in appearance, with the ascospores heterokaryotic and viable. The Eight-spore gene E, which shows variable penetrance, was used to obtain N. tetrasperma asci in which two to eight spores are small and homokaryotic. When killer and sensitive alleles are segregating in the presence of E, only those ascospores that contain a killer allele survive. Half of the small ascospores are killed. In crosses of Sk-2(K) X Sk-3(K) (with E heterozygous), effectively all small ascospores are killed. The ability of N. tetrasperma to carry killer elements in cryptic condition suggests a possible role for Spore killers in the origin of pseudohomothallism, with adoption of the four-spored mode restoring ascospore viability of crosses in which killing would otherwise occur. PMID:1834522
The role of immunosuppression in squamous cell carcinomas arising in seborrheic keratosis.
Conic, Ruzica Z; Napekoski, Karl; Schuetz, Heidi; Piliang, Melissa; Bergfeld, Wilma; Atanaskova Mesinkovska, Natasha
2017-06-01
Seborrheic keratoses (SK) are common skin neoplasms considered to be benign. Reports of associated squamous cell carcinoma arising within seborrheic keratosis (SCC-SK) have been described. To describe the histopathologic characteristics of SCC-SK and identify predisposing factors in formation of these rare lesions. There were 162 cases of SCC-SK in a span of a decade (2003-2014). All of the histopathologic specimens and medical records were reviewed. Data from these patients were compared to a control group with seborrheic keratosis who were matched by age, sex, and location of lesion from the same time period (n = 162). SCC-SK has the classic histopathologic features of SK, such as hyperkeratosis, parakeratosis, papillomatosis, and pseudohorn cysts. The areas of squamous cell carcinoma were characterized by areas of squamous dysplasia (100%), hypogranulosis (79.6%), squamous eddies (79.6%), solar elastosis (80.9%), and brown pigmentation (59.9%). Patients with a history of immunosuppression had an increased risk for developing SCC-SK (19% vs 3%; P < .01), particularly when inhibition was transplant-associated (10% vs 0%; P < .01). This was a single center, retrospective study. SCC-SK occurs more often in elderly men with a history of immunosuppression associated with organ transplants. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.
Air-kerma strength determination of a new directional (103)Pd source.
Aima, Manik; Reed, Joshua L; DeWerd, Larry A; Culberson, Wesley S
2015-12-01
A new directional (103)Pd planar source array called a CivaSheet™ has been developed by CivaTech Oncology, Inc., for potential use in low-dose-rate (LDR) brachytherapy treatments. The array consists of multiple individual polymer capsules called CivaDots, containing (103)Pd and a gold shield that attenuates the radiation on one side, thus defining a hot and cold side. This novel source requires new methods to establish a source strength metric. The presence of gold material in such close proximity to the active (103)Pd region causes the source spectrum to be significantly different than the energy spectra of seeds normally used in LDR brachytherapy treatments. In this investigation, the authors perform air-kerma strength (S(K)) measurements, develop new correction factors for these measurements based on an experimentally verified energy spectrum, and test the robustness of transferring S(K) to a well-type ionization chamber. S(K) measurements were performed with the variable-aperture free-air chamber (VAFAC) at the University of Wisconsin Medical Radiation Research Center. Subsequent measurements were then performed in a well-type ionization chamber. To realize the quantity S(K) from a directional source with gold material present, new methods and correction factors were considered. Updated correction factors were calculated using the MCNP 6 Monte Carlo code in order to determine S(K) with the presence of gold fluorescent energy lines. In addition to S(K) measurements, a low-energy high-purity germanium (HPGe) detector was used to experimentally verify the calculated spectrum, a sodium iodide (NaI) scintillating counter was used to verify the azimuthal and polar anisotropy, and a well-type ionization chamber was used to test the feasibility of disseminating S(K) values for a directional source within a cylindrically symmetric measurement volume. The UW VAFAC was successfully used to measure the S(K) of four CivaDots with reproducibilities within 0.3%. Monte Carlo methods were used to calculate the UW VAFAC correction factors and the calculated spectrum emitted from a CivaDot was experimentally verified with HPGe detector measurements. The well-type ionization chamber showed minimal variation in response (<1.5%) as a function of source positioning angle, indicating that an American Association of Physicists in Medicine (AAPM) Accredited Dosimetry Calibration Laboratory calibrated well chamber would be a suitable device to transfer an S(K)-based calibration to a clinical user. S(K) per well-chamber ionization current ratios were consistent among the four dots measured. Additionally, the measurements and predictions of anisotropy show uniform emission within the solid angle of the VAFAC, which demonstrates the robustness of the S(K) measurement approach. This characterization of a new (103)Pd directional brachytherapy source helps to establish calibration methods that could ultimately be used in the well-established AAPM Task Group 43 formalism. Monte Carlo methods accurately predict the changes in the energy spectrum caused by the fluorescent x-rays produced in the gold shield.
NASA Astrophysics Data System (ADS)
Jing, Xin; Mi, Hao-Yang; Peng, Xiang-Fang; Turng, Lih-Sheng
2016-03-01
Surface properties of tissue engineering scaffolds such as topography, hydrophilicity, and functional groups play a vital role in cell adhesion, migration, proliferation, and apoptosis. First, poly(ɛ-caprolactone) (PCL) shish-kebab scaffolds (PCL-SK), which feature a three-dimensional structure comprised of electrospun PCL nanofibers covered by periodic, self-induced PCL crystal lamellae on the surface, was created to mimic the nanotopography of native collagen fibrils in the extracellular matrix (ECM). Second, matrigel was covalently immobilized on the surface of alkaline hydrolyzed PCL-SK scaffolds to enhance their hydrophilicity. This combined approach not only mimics the nanotopography of native collagen fibrils, but also simulates the surface features of collagen fibrils for cell growth. To investigate the viability of such scaffolds, HEF1 fibroblast cell assays were conducted and the results revealed that the nanotopography of the PCL-SK scaffolds facilitated cell adhesion and proliferation. The matrigel functionalization on PCL-SK scaffolds further enhanced cellular response, which suggested elevated biocompatibility and greater potential for skin tissue engineering applications.
Sharma, Shalini; Mulik, Sachin; Kumar, Naveen; Suryawanshi, Amol; Rouse, Barry T.
2011-01-01
Corneal neovascularization represents a key step in the blinding inflammatory stromal keratitis (SK) lesion caused by ocular infection with herpes simplex virus (HSV). In this report, we describe a novel approach for limiting the angiogenesis caused by HSV infection of the mouse eye. We show that topical or systemic administration of the Src kinase inhibitor (TG100572) that inhibits downstream molecules involved in the vascular endothelial growth factor (VEGF) signaling pathway resulted in markedly diminished levels of HSV-induced angiogenesis and significantly reduced the severity of SK lesions. Multiple mechanisms were involved in the inhibitory effects. These included blockade of IL-8/CXCL1 involved in inflammatory cells recruitment that are a source of VEGF, diminished cellular infiltration in the cornea, and reduced proliferation and migration of CD4+ T cells into the corneas. As multiple angiogenic factors (VEGF and basic fibroblast growth factor [bFGF]) play a role in promoting angiogenesis during SK and since Src kinases are involved in signaling by many of them, the use of Src kinase inhibition represents a promising way of limiting the severity of SK lesions the most common cause of infectious blindness in the Western world. PMID:21471229
Pavan, Mauro; Beninatto, Riccardo; Galesso, Devis; Panfilo, Susi; Vaccaro, Susanna; Messina, Luciano; Guarise, Cristian
2016-04-01
Recombinant human hyaluronidase has been used in the interstitial matrix to promote the dispersion of therapeutics. The production and isolation of an extracellular hyaluronidase from Streptomyces koganeiensis (rHyal_Sk) has recently been described. The specificity of rHyal_Sk has been assessed against heparan sulfate, chondroitin sulfates and sulfated HAs. The oligomers generated by HA degradation have been investigated by MALDI-TOF MS analysis. rHyal_Sk has been compared with BTH and PH20 in vitro, against cross-linked HA (ACP) and HA-aggrecan complex, and in vivo, by means of a diffusion assay in nude mice. Depolymerization of HA by rHyal_Sk gave tetra-, hexa- and octasaccharides in high yields. The reaction mechanism and the high HA specificity were demonstrated. The in vivo diffusion assay, supported by the in vitro tests, evidenced an initially enhanced enzymatic activity of rHyal_Sk compared to BTH and PH20. rHyal_Sk, compared to BTH and PH20, showed higher substrate specificity and no inhibition from GAGs sulfate, together with a superior performance for HA depolymerization in ECM. As better predictive tests for the in vivo activity of hyaluronidase we developed two assays based on the degradation of ACP or of the HA-aggrecan complex. rHyal_Sk is a new potential spreading factor for intradermal drug administration. Hyaluronidases of distinct classes, that show equivalent activities in a common turbidimetric assay, could have different potencies and dose-efficacies in vivo which influences the therapeutic effect. The new proposed in vitro tests are designed to obtain a predictive characterization of the enzyme activity in vivo. Copyright © 2015 Elsevier B.V. All rights reserved.
Clark, Nancye; Patel, Jean B.
2013-01-01
Vancomycin-resistant Staphylococcus aureus (VRSA) is thought to result from the in vivo conjugative transfer of a vanA plasmid from an Enterococcus sp. to S. aureus. We studied bacterial isolates from VRSA cases that occurred in the United States to identify microbiological factors which may contribute to this plasmid transfer. First, vancomycin-susceptible, methicillin-resistant S. aureus (MRSA) isolates from five VRSA cases were tested for their ability to accept foreign DNA by conjugation in mating experiments with Enterococcus faecalis JH2-2 containing pAM378, a pheromone-response conjugative plasmid. All of the MRSA isolates accepted the plasmid DNA with similar transfer efficiencies (∼10−7/donor CFU) except for one isolate, MRSA8, for which conjugation was not successful. The MRSA isolates were also tested as recipients in mating experiments between an E. faecalis isolate with an Inc18-like vanA plasmid that was isolated from a VRSA case patient. Conjugative transfer was successful for 3/5 MRSA isolates. Successful MRSA recipients carried a pSK41-like plasmid, a staphylococcal conjugative plasmid, whereas the two unsuccessful MRSA recipients did not carry pSK41. The transfer of a pSK41-like plasmid from a successful MRSA recipient to the two unsuccessful recipients resulted in conjugal transfer of the Inc18-like vanA plasmid from E. faecalis at a frequency of 10−7/recipient CFU. In addition, conjugal transfer could be achieved for pSK41-negative MRSA in the presence of a cell-free culture filtrate from S. aureus carrying a pSK41-like plasmid at a frequency of 10−8/recipient CFU. These results indicated that a pSK41-like plasmid can facilitate the transfer of an Inc18-like vanA plasmid from E. faecalis to S. aureus, possibly via an extracellular factor produced by pSK41-carrying isolates. PMID:23089754
Kim, Yoon Jung; Kim, Sin Gon; Lee, Yo Han
2018-01-01
Previous studies on obesity status among North Korean refugees (NKRs) have been limited. We investigated mean body mass index (BMI), waist circumference (WC), and general and central obesity prevalence among NKRs in South Korea (SK) by duration after defection from North Korea (NK), using cross-sectional data of the North Korean Refugee Health in South Korea (NORNS) study and compared these data with a sample from the general South Korean population (the fifth Korea National Health and Nutrition Examination Survey). The prevalence of general and central obesity among NKRs with duration after defection from NK of less than five years were lower than among South Koreans, except for central obesity among NKR females (obesity prevalence, 19% (12–27%) vs. 39% (34–44%) for NK vs. SK males (p < 0.001) and 19% (14–24%) vs. 27% (24–29%) for NK vs. SK females (p = 0.076); central obesity prevalence, 13% (6–19%) vs. 24% (20–29%) for NK vs. SK males (p = 0.011) and 22% (17–28%) vs. 20% (18–22%) for NK vs. SK females (p = 0.382)). The prevalence of general and central obesity among NKRs with duration after defection from NK (≥10 years) were comparable to those of South Koreans in both genders (obesity prevalence, 34% (18–50%) vs. 39% (34–44%) for NK vs. SK males (p = 0.690) and 23% (18–29%) vs. 27% (24–29%) for NK vs. SK females (0.794); central obesity prevalence, 21% (7–34%) vs. 24% (20–29%) for NK vs. SK males (p = 0.642); 22% (17–28%) vs. 20% (18–22%) for NK vs. SK females (p = 0.382)). Male sex, age and longer duration after defection from NK (≥10 years) were positively associated with obesity. As for central obesity, age was the only independently associated factor. NKR females with duration after defection from NK of less than five years had comparable central obesity prevalence to South Korean females in spite of a lower BMI, which suggests that we need further monitoring for their metabolic health among NKRs in SK. PMID:29677154
Kim, Yoon Jung; Kim, Sin Gon; Lee, Yo Han
2018-04-20
Previous studies on obesity status among North Korean refugees (NKRs) have been limited. We investigated mean body mass index (BMI), waist circumference (WC), and general and central obesity prevalence among NKRs in South Korea (SK) by duration after defection from North Korea (NK), using cross-sectional data of the North Korean Refugee Health in South Korea (NORNS) study and compared these data with a sample from the general South Korean population (the fifth Korea National Health and Nutrition Examination Survey). The prevalence of general and central obesity among NKRs with duration after defection from NK of less than five years were lower than among South Koreans, except for central obesity among NKR females (obesity prevalence, 19% (12⁻27%) vs. 39% (34⁻44%) for NK vs. SK males ( p < 0.001) and 19% (14⁻24%) vs. 27% (24⁻29%) for NK vs. SK females ( p = 0.076); central obesity prevalence, 13% (6⁻19%) vs. 24% (20⁻29%) for NK vs. SK males ( p = 0.011) and 22% (17⁻28%) vs. 20% (18⁻22%) for NK vs. SK females ( p = 0.382)). The prevalence of general and central obesity among NKRs with duration after defection from NK (≥10 years) were comparable to those of South Koreans in both genders (obesity prevalence, 34% (18⁻50%) vs. 39% (34⁻44%) for NK vs. SK males ( p = 0.690) and 23% (18⁻29%) vs. 27% (24⁻29%) for NK vs. SK females (0.794); central obesity prevalence, 21% (7⁻34%) vs. 24% (20⁻29%) for NK vs. SK males ( p = 0.642); 22% (17⁻28%) vs. 20% (18⁻22%) for NK vs. SK females ( p = 0.382)). Male sex, age and longer duration after defection from NK (≥10 years) were positively associated with obesity. As for central obesity, age was the only independently associated factor. NKR females with duration after defection from NK of less than five years had comparable central obesity prevalence to South Korean females in spite of a lower BMI, which suggests that we need further monitoring for their metabolic health among NKRs in SK.
Identification of New Drug Targets in Multi-Drug Resistant Bacterial Infections
2012-10-01
readout from malachite green, which detects the presence of inorganic phosphate with a simple color change. We have performed preliminary tests, however...SK requires ATP as a co-factor, which substantially increases the background by reacting with the malachite green. For the coupled reaction of SK
Stationkeeping Monte Carlo Simulation for the James Webb Space Telescope
NASA Technical Reports Server (NTRS)
Dichmann, Donald J.; Alberding, Cassandra M.; Yu, Wayne H.
2014-01-01
The James Webb Space Telescope (JWST) is scheduled to launch in 2018 into a Libration Point Orbit (LPO) around the Sun-Earth/Moon (SEM) L2 point, with a planned mission lifetime of 10.5 years after a six-month transfer to the mission orbit. This paper discusses our approach to Stationkeeping (SK) maneuver planning to determine an adequate SK delta-V budget. The SK maneuver planning for JWST is made challenging by two factors: JWST has a large Sunshield, and JWST will be repointed regularly producing significant changes in Solar Radiation Pressure (SRP). To accurately model SRP we employ the Solar Pressure and Drag (SPAD) tool, which uses ray tracing to accurately compute SRP force as a function of attitude. As an additional challenge, the future JWST observation schedule will not be known at the time of SK maneuver planning. Thus there will be significant variation in SRP between SK maneuvers, and the future variation in SRP is unknown. We have enhanced an earlier SK simulation to create a Monte Carlo simulation that incorporates random draws for uncertainties that affect the budget, including random draws of the observation schedule. Each SK maneuver is planned to optimize delta-V magnitude, subject to constraints on spacecraft pointing. We report the results of the Monte Carlo simulations and discuss possible improvements during flight operations to reduce the SK delta-V budget.
Kuo, Yung-Chih; Wang, Cheng-Ting
2014-07-01
A liposomal system with surface lactoferrin (Lf) was developed for delivering neuron growth factor (NGF) across the blood-brain barrier (BBB) and improving the viability of neuron-like SK-N-MC cells with deposited β-amyloid peptide (Aβ). The Lf-grafted liposomes carrying NGF (Lf/NGF-liposomes) were applied to a monolayer of human brain-microvascular endothelial cells (HBMECs) regulated by human astrocytes (HAs) and to fibrillar Aβ1-42-insulted SK-N-MC cells. An increase in cholesterol mole percentage enhanced the particle size, absolute value of zeta potential, and physical stability, however, reduced the entrapment efficiency and release rate of NGF. In addition, an increase in Lf concentration increased the particle size, surface nitrogen percentage, NGF permeability across the BBB, and viability of HBMECs, HAs, and SK-N-MC cells, however, decreased the absolute value of zeta potential, surface phosphorus percentage, and loading efficiency of Lf. After treating with Lf/NGF-liposomes, a higher Aβ concentration yielded a lower survival of SK-N-MC cells. The current Lf/NGF-liposomes are efficacious drug carriers to target the BBB and inhibit the Aβ-induced neurotoxicity as potential pharmacotherapy for Alzheimer's disease. Copyright © 2014 Elsevier Ltd. All rights reserved.
The pair correlation function of krypton in the critical region: theory and experiment
NASA Astrophysics Data System (ADS)
Barocchi, F.; Chieux, P.; Fontana, R.; Magli, R.; Meroni, A.; Parola, A.; Reatto, L.; Tau, M.
1997-10-01
We present the results of high-precision measurements of the structure factor S(k) of krypton in the near-critical region of the liquid - vapour phase transition for values of k ranging from 1.5 up to 0953-8984/9/42/003/img15. The experimental results are compared with a theoretical calculation based on the hierarchical reference theory (HRT) with an accurate potential which includes two- and three-body contributions. The theory is based on a new implementation of HRT in which we avoid the use of hard spheres as a reference system. With this soft-core formulation we find a generally good agreement with experiments both at large k, where S(k) probes the short-range correlations, as well as at small k, where critical fluctuations become dominant. Also, for the density derivative of the pair correlation function there is an overall good agreement between theory and experiment.
Calculating degree-based topological indices of dominating David derived networks
NASA Astrophysics Data System (ADS)
Ahmad, Muhammad Saeed; Nazeer, Waqas; Kang, Shin Min; Imran, Muhammad; Gao, Wei
2017-12-01
An important area of applied mathematics is the Chemical reaction network theory. The behavior of real world problems can be modeled by using this theory. Due to applications in theoretical chemistry and biochemistry, it has attracted researchers since its foundation. It also attracts pure mathematicians because it involves interesting mathematical structures. In this report, we compute newly defined topological indices, namely, Arithmetic-Geometric index (AG1 index), SK index, SK1 index, and SK2 index of the dominating David derived networks [1, 2, 3, 4, 5].
TAF1, From a General Transcription Factor to Modulator of Androgen Receptor in Prostate Cancer
2009-02-01
TN, Ferguson HA, Galasinski SK, Seto AG, Goodrich JA 2001 c-Jun binds the N terminus of human TAF(II)250 to derepress RNA polymerase II... Galasinski SK, Goodrich JA 2004 The basic leucine zipper domain of c-Jun functions in transcriptional activation through interaction with the N
Optical spectroscopy of the blue supergiant Sk-69° 279 and its circumstellar shell with SALT
NASA Astrophysics Data System (ADS)
Gvaramadze, V. V.; Kniazev, A. Y.; Maryeva, O. V.; Berdnikov, L. N.
2018-02-01
We report the results of optical spectroscopy of the blue supergiant Sk-69° 279 and its circular shell in the Large Magellanic Cloud (LMC) with the Southern African Large Telescope (SALT). We classify Sk-69° 279 as an O9.2 Iaf star and analyse its spectrum by using the stellar atmosphere code CMFGEN, obtaining a stellar temperature of ≈30 kK, a luminosity of log (L*/ L⊙) = 5.54, a mass-loss rate of log (\\dot{M}/ M_{⊙} yr^{-1}) = -5.26, and a wind velocity of 800km s-1. We found also that Sk-69° 279 possesses an extended atmosphere with an effective temperature of ≈24 kK and that its surface helium and nitrogen abundances are enhanced, respectively, by factors of ≈2 and 20-30. This suggests that either Sk-69° 279 was initially a (single) fast-rotating ( ≳ 400 km s- 1) star, which only recently evolved off the main sequence, or that it is a product of close binary evolution. The long-slit spectroscopy of the shell around Sk-69° 279 revealed that its nitrogen abundance is enhanced by the same factor as the stellar atmosphere, which implies that the shell is composed mostly of the CNO processed material lost by the star. Our findings support previous propositions that some massive stars can produce compact circumstellar shells and, presumably, appear as luminous blue variables while they are still on the main sequence or have only recently left it.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jing, Xin, E-mail: jingxinscut@gmail.com; Mi, Hao-Yang; Wisconsin Institutes for Discovery, University of Wisconsin-Madison, 53715
Surface properties of tissue engineering scaffolds such as topography, hydrophilicity, and functional groups play a vital role in cell adhesion, migration, proliferation, and apoptosis. First, poly(ε-caprolactone) (PCL) shish-kebab scaffolds (PCL-SK), which feature a three-dimensional structure comprised of electrospun PCL nanofibers covered by periodic, self-induced PCL crystal lamellae on the surface, was created to mimic the nanotopography of native collagen fibrils in the extracellular matrix (ECM). Second, matrigel was covalently immobilized on the surface of alkaline hydrolyzed PCL-SK scaffolds to enhance their hydrophilicity. This combined approach not only mimics the nanotopography of native collagen fibrils, but also simulates the surface featuresmore » of collagen fibrils for cell growth. To investigate the viability of such scaffolds, HEF1 fibroblast cell assays were conducted and the results revealed that the nanotopography of the PCL-SK scaffolds facilitated cell adhesion and proliferation. The matrigel functionalization on PCL-SK scaffolds further enhanced cellular response, which suggested elevated biocompatibility and greater potential for skin tissue engineering applications.« less
NASA Astrophysics Data System (ADS)
Buchta, David; Freund, Jonathan
2017-11-01
High-speed (supersonic) turbulent shear flows are well-known to radiate pressure-wave patterns that have higher positive peaks than negative valleys, which yields a notable skewness, usually with Sk > 0.4 . Direct numerical simulations (DNS) of planar turbulent mixing layers at different Mach numbers (M) are used to examine this. The baseline simulations, of an air-like gas at speeds up to M = 3.5 , reproduced the observed behavior of jets. Simulations initialized with corresponding instability modes show that Sk increases linearly with the velocity amplitude (Mt =√{ui' ui'} /co), reflecting the M dependence of the DNS, which can be related to simpler gas dynamic flows. Simulations with a stiffened-gas equation of state (often used to model liquids) show essentially the same Mach-number dependence, despite the nominally greater resistance to compressibility. Turbulence simulations with an artificial energy reallocation mechanism, imposed to alter its structure, show little change in Sk. Finally, we also consider significantly increased bulk viscosity to suppress dilatation. In this case, Sk diminishes along with the sound-field intensity, though the turbulence stresses themselves are nearly unchanged.
Clinical and Histopathological Investigation of Seborrheic Keratosis
Roh, Nam Kyung; Hahn, Hyung Jin; Lee, Yang Won; Choe, Yong Beom
2016-01-01
Background Seborrheic keratosis (SK) is one of the most common epidermal tumors of the skin. However, only a few large-scale clinicohistopathological investigations have been conducted on SK or on the possible correlation between histopathological SK subtype and location. Objective The aim of this study was to analyze the clinical and histopathological features of a relatively large number of cases of diagnosed SK. Methods Two hundred and seventy-one pathology slides of skin tissue from patients with clinically diagnosed SK and 206 cases of biopsy-proven SK were analyzed. The biopsy-proven cases of SK were assessed for histopathological subclassification. The demographic, clinical, and histopathological data of the patients were collected for analysis of associated factors. Results The most frequent histopathological subtype was the acanthotic type, followed by mixed, hyperkeratotic, melanoacanthoma, clonal, irritated, and adenoid types; an unexpectedly high percentage (9.2%) of the melanoacanthoma variant was observed. The adenoid type was more common in sun-exposed sites than in sun-protected sites (p=0.028). Premalignant and malignant entities together represented almost one-quarter (24.2%) of the clinicopathological mismatch cases (i.e., mismatch between the clinical and histopathological diagnoses). Regarding the location of SK development, the frequency of mismatch for the sun-exposed areas was significantly higher than that for sun-protected areas (p=0.043). Conclusion The adenoid type was more common in sun-exposed sites. Biopsy sampling should be performed for lesions situated in sun-exposed areas to exclude other premalignant or malignant diseases. PMID:27081260
Milkau, Malte; Köhler, Ralf; de Wit, Cor
2010-09-01
Skeletal muscle activity requires substantial increases in blood flow, and the underlying vasodilation involves endothelial activity, but the contribution of the endothelium-dependent hyperpolarizing factor (EDHF) is only poorly defined. In EDHF signaling, endothelial hyperpolarization mediated by the Ca(2+)-activated K(+) channels SK3 and IK1 is a key step and also initiates gap junction-dependent conducted dilations. We assessed the role of SK3, IK1, and connexin40 (Cx40) in muscular contraction-induced dilations in the microcirculation in vivo. Hitherto, arterioles were observed in the electrically stimulated cremaster skeletal muscle of anesthetized mice lacking SK3, IK1, or Cx40 using intravital microscopy. Genetic deficiency of SK3, but not of IK1, strongly attenuated dilations to muscular contraction. Similarly, pharmacologic blockade of SK3 by the specific blocker UCL1684 impaired such dilations in wild-type and IK1-deficient mice. In contrast, IK1 was required for acetylcholine-induced dilations. Genetic deficiency of Cx40 also attenuated dilations induced by muscular contraction but not by acetylcholine. These data support the concept that endothelial hyperpolarization through activation of SK3 contributes to exercise hyperemia and the hyperpolarization ascends the vascular tree through gap junctions formed by Cx40 to orchestrate dilation. The differential impact of SK3- and IK1-deficiency on dilations to distinct stimuli suggests stimulus-dependent activation of these endothelial channels.
Production of coagulation factor VII in human cell lines Sk-Hep-1 and HKB-11.
Corrêa de Freitas, Marcela Cristina; Bomfim, Aline de Sousa; Mizukami, Amanda; Picanço-Castro, Virgínia; Swiech, Kamilla; Covas, Dimas Tadeu
2017-09-01
Recombinant factor VII (rFVII) is the main therapeutic choice for hemophilia patients who have developed inhibitory antibodies against conventional treatments (FVIII and FIX). Because of the post-translational modifications, rFVII needs to be produced in mammalian cell lines. In this study, for the first time, we have shown efficient rFVII production in HepG2, Sk-Hep-1, and HKB-11 cell lines. Experiments in static conditions for a period of 96 h showed that HepG2-FVII produced the highest amounts of rhFVII, with an average of 1843 ng/mL. Sk-hep-1-FVII cells reached a maximum protein production of 1432 ng/mL and HKB-11-FVII cells reached 1468 ng/mL. Sk-Hep-1-rFVII and HKB-11-rFVII were selected for the first step of scale-up. Over 10 days of spinner flask culture, HKB-11 and SK-Hep-1 cells showed a cumulative production of rFVII of 152 μg and 202.6 μg in 50 mL, respectively. Thus, these human cell lines can be used for an efficient production of recombinant FVII. With more investment in basic research, human cell lines can be optimized for the commercial production of different bio therapeutic proteins. Copyright © 2017 Elsevier Inc. All rights reserved.
Ishida, Takahiro; Sakaguchi, Ikuyo
2007-05-01
UVB irradiation is an important inducer of biological changes in skin and can activate inflammatory reactions and apoptotic pathways, leading to skin damage. A root extract of Lithospermum erythrorhizon (SK), which has naphthoquinone pigments containing shikonin and shikonin derivatives, is known for its anti-inflammatory, anti-bacterial, and anti-tumor activity, and for its scavenging of reactive oxygen species. However, the effect of SK against UV damage is not clear. The aim of this study was to evaluate the efficacy of SK against UVB induced damage in normal human epidermal keratinocytes (NHEK). UVB-irradiated NHEK showed decreased cell viability, increased production of interleukin (IL)-1alpha, IL-6, IL-8, and tumor necrosis factor-alpha, and induced apoptosis. In an apoptosis pathway assay, UVB-irradiated NHEK showed increased caspase-3 activity, p53 and its phosphorylation at serine 15 compared with non-irradiated cells. All these effects induced by UVB irradiation were clearly inhibited by treatment with SK before and after UVB irradiation for 24 h. It is suggested that SK can protect epidermal cells against harmful effects of UVB irradiation and that SK treatment is probably beneficial for photoprotection of the skin.
Tsutsumimoto, Takahiro; Williams, Paul; Yoneda, Toshiyuki
2014-01-01
Neuroblastoma (NB), which arises from embryonic neural crest cells, is the most common extra-cranial solid tumor of childhood. Approximately half of NB patients manifest bone metastasis accompanied with bone pain, fractures and bone marrow failure, leading to disturbed quality of life and poor survival. To study the mechanism of bone metastasis of NB, we established an animal model in which intracardiac inoculation of the SK-N-AS human NB cells in nude mice developed osteolytic bone metastases with increased osteoclastogenesis. SK-N-AS cells induced the expression of receptor activator of NF-κB ligand and osteoclastogenesis in mouse bone marrow cells in the co-culture. SK-N-AS cells expressed COX-2 mRNA and produced substantial amounts of prostaglandin E2 (PGE2). In contrast, the SK-N-DZ and SK-N-FI human NB cells failed to develop bone metastases, induce osteoclastogenesis, express COX-2 mRNA and produce PGE2. Immunohistochemical examination of SK-N-AS bone metastasis and subcutaneous tumor showed strong expression of COX-2. The selective COX-2 inhibitor NS-398 inhibited PGE2 production and suppressed bone metastases with reduced osteoclastogenesis. NS-398 also inhibited subcutaneous SK-N-AS tumor development with decreased angiogenesis and vascular endothelial growth factor-A expression. Of interest, metastasis to the adrenal gland, a preferential site for NB development, was also diminished by NS-398. Our results suggest that COX2/PGE2 axis plays a critical role in the pathophysiology of osteolytic bone metastases and tumor development of the SK-NS-AS human NB. Inhibition of angiogenesis by suppressing COX-2/PGE2 may be an effective therapeutic approach for children with NB. PMID:26909300
Self-consistent Hartree-Fock RPA calculations in 208Pb
NASA Astrophysics Data System (ADS)
Taqi, Ali H.; Ali, Mohammed S.
2018-01-01
The nuclear structure of 208Pb is studied in the framework of the self-consistent random phase approximation (SCRPA). The Hartree-Fock mean field and single particle states are used to implement a completely SCRPA with Skyrme-type interactions. The Hamiltonian is diagonalised within a model space using five Skyrme parameter sets, namely LNS, SkI3, SkO, SkP and SLy4. In view of the huge number of the existing Skyrme-force parameterizations, the question remains which of them provide the best description of data. The approach attempts to accurately describe the structure of the spherical even-even nucleus 208Pb. To illustrate our approach, we compared the binding energy, charge density distribution, excitation energy levels scheme with the available experimental data. Moreover, we calculated isoscalar and isovector monopole, dipole, and quadrupole transition densities and strength functions.
Identify High-Quality Protein Structural Models by Enhanced K-Means.
Wu, Hongjie; Li, Haiou; Jiang, Min; Chen, Cheng; Lv, Qiang; Wu, Chuang
2017-01-01
Background. One critical issue in protein three-dimensional structure prediction using either ab initio or comparative modeling involves identification of high-quality protein structural models from generated decoys. Currently, clustering algorithms are widely used to identify near-native models; however, their performance is dependent upon different conformational decoys, and, for some algorithms, the accuracy declines when the decoy population increases. Results. Here, we proposed two enhanced K -means clustering algorithms capable of robustly identifying high-quality protein structural models. The first one employs the clustering algorithm SPICKER to determine the initial centroids for basic K -means clustering ( SK -means), whereas the other employs squared distance to optimize the initial centroids ( K -means++). Our results showed that SK -means and K -means++ were more robust as compared with SPICKER alone, detecting 33 (59%) and 42 (75%) of 56 targets, respectively, with template modeling scores better than or equal to those of SPICKER. Conclusions. We observed that the classic K -means algorithm showed a similar performance to that of SPICKER, which is a widely used algorithm for protein-structure identification. Both SK -means and K -means++ demonstrated substantial improvements relative to results from SPICKER and classical K -means.
Identify High-Quality Protein Structural Models by Enhanced K-Means
Li, Haiou; Chen, Cheng; Lv, Qiang; Wu, Chuang
2017-01-01
Background. One critical issue in protein three-dimensional structure prediction using either ab initio or comparative modeling involves identification of high-quality protein structural models from generated decoys. Currently, clustering algorithms are widely used to identify near-native models; however, their performance is dependent upon different conformational decoys, and, for some algorithms, the accuracy declines when the decoy population increases. Results. Here, we proposed two enhanced K-means clustering algorithms capable of robustly identifying high-quality protein structural models. The first one employs the clustering algorithm SPICKER to determine the initial centroids for basic K-means clustering (SK-means), whereas the other employs squared distance to optimize the initial centroids (K-means++). Our results showed that SK-means and K-means++ were more robust as compared with SPICKER alone, detecting 33 (59%) and 42 (75%) of 56 targets, respectively, with template modeling scores better than or equal to those of SPICKER. Conclusions. We observed that the classic K-means algorithm showed a similar performance to that of SPICKER, which is a widely used algorithm for protein-structure identification. Both SK-means and K-means++ demonstrated substantial improvements relative to results from SPICKER and classical K-means. PMID:28421198
Costa, Luciano T; Ribeiro, Mauro C C
2006-05-14
Molecular dynamics (MD) simulations have been performed for prototype models of polymer electrolytes in which the salt is an ionic liquid based on 1-alkyl-3-methylimidazolium cations and the polymer is poly(ethylene oxide), PEO. The MD simulations were performed by combining the previously proposed models for pure ionic liquids and polymer electrolytes containing simple inorganic ions. A systematic investigation of ionic liquid concentration, temperature, and the 1-alkyl- chain length, [1,3-dimethylimidazolium]PF6, and [1-butyl-3-methylimidazolium]PF6, effects on resulting equilibrium structure is provided. It is shown that the ionic liquid is dispersed in the polymeric matrix, but ionic pairs remain in the polymer electrolyte. Imidazolium cations are coordinated by both the anions and the oxygen atoms of PEO chains. Probability density maps of occurrences of nearest neighbors around imidazolium cations give a detailed physical picture of the environment experienced by cations. Conformational changes on PEO chains upon addition of the ionic liquid are identified. The equilibrium structure of simulated systems is also analyzed in reciprocal space by using the static structure factor, S(k). Calculated S(k) display a low wave-vector peak, indicating that spatial correlation in an extended-range order prevail in the ionic liquid polymer electrolytes. Long-range correlations are assigned to nonuniform distribution of ionic species within the simulation box.
TAF1, From a General Transcription Factor to Modulator of Androgen Receptor in Prostate Cancer
2010-02-01
kinase CK2. Mol Cell Biochem 316:99-106 21. Lively TN, Ferguson HA, Galasinski SK, Seto AG, Goodrich JA 2001 c-Jun binds the N terminus of human TAF(II...Nguyen TN, Galasinski SK, Goodrich JA 2004 The basic leucine zipper domain of c-Jun functions in transcriptional activation through interaction with
Jing, Xin; Mi, Hao-Yang; Wang, Xin-Chao; Peng, Xiang-Fang; Turng, Lih-Sheng
2015-04-01
In this work, scaffolds with a shish-kebab (SK) structure formed by poly(ε-caprolactone) (PCL) nanofibers and chitosan-PCL (CS-PCL) copolymers were prepared via electrospinning and subsequent crystallization for bone tissue engineering applications. The aim of this study was to introduce nanosized topography and the high biocompatibility of chitosan onto PCL nanofibers to enhance cell affinity to PCL scaffolds. CS-PCL copolymers with various ratios were synthesized, and then spontaneously crystallized as kebabs onto the electrospun PCL fibers, which acted as shishes. Scanning electron microscopy (SEM) results demonstrated that the copolymer with PCL to chitosan ratio of 8.8 could hierarchically decorate the PCL nanofibers and formed well-shaped kebabs on the PCL nanofiber surface. Water contact angle tests and biomimetic activity experiments revealed that the shish-kebab scaffolds with CS-PCL kebabs (PCL-SK(CS-PCL(8.8))) showed enhanced hydrophilicity and mineralization ability compared with smooth PCL and PCL-SK(PCL) shish-kebab scaffolds. Osteoblast-like MG63 cells cultured on the PCL-SK(CS-PCL(8.8)) scaffolds showed optimizing cell attachment, cell viability, and metabolic activity, demonstrating that this kind of scaffold has potential applications in bone tissue engineering.
Structural basis of agrin-LRP4-MuSK signaling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zong, Yinong; Zhang, Bin; Gu, Shenyan
Synapses are the fundamental units of neural circuits that enable complex behaviors. The neuromuscular junction (NMJ), a synapse formed between a motoneuron and a muscle fiber, has contributed greatly to understanding of the general principles of synaptogenesis as well as of neuromuscular disorders. NMJ formation requires neural agrin, a motoneuron-derived protein, which interacts with LRP4 (low-density lipoprotein receptor-related protein 4) to activate the receptor tyrosine kinase MuSK (muscle-specific kinase). However, little is known of how signals are transduced from agrin to MuSK. Here, we present the first crystal structure of an agrin-LRP4 complex, consisting of two agrin-LRP4 heterodimers. Formation ofmore » the initial binary complex requires the z8 loop that is specifically present in neuronal, but not muscle, agrin and that promotes the synergistic formation of the tetramer through two additional interfaces. We show that the tetrameric complex is essential for neuronal agrin-induced acetylcholine receptor (AChR) clustering. Collectively, these results provide new insight into the agrin-LRP4-MuSK signaling cascade and NMJ formation and represent a novel mechanism for activation of receptor tyrosine kinases.« less
Improvement of SPM nonlinear limit by chirped duobinary PolSK transmission
NASA Astrophysics Data System (ADS)
Yang, Lixiu; Fan, Jiayu; Wang, Lutang; Huang, Zhaoming
2005-02-01
In today's terrestrial long-haul optical fiber communication systems, high channel powers are required to obtain a large transmission distance with reasonable optical amplifier spacing. In such systems, however, the presence of nonlinear effects such as the self-phase modulation (SPM) and the fiber dispersion as well as their combined effects, called SPM-induced nonlinear limitation or SPM limit, will seriously degrade the system performances in respect of the effective transmission distance and ultimately become a limiting factor in high-speed, long-haul optical fiber transmission.In this paper, a new transmission format: chirped duobinary PolSK transmission, has been proposed to generate a pre-chirped duobianry signal with fixed polarity (either positive or negative), which is modulated by a PolSK modulator. This format is based on a transmitter setup consisting of a duobinary PolSK Modulation transmitter followed by an additional phase modulator. The chirped duobinary PolSK transmission reduces the signal degradation and spectral broadening in the nonlinear regime significantly. Thus it shifts this SPM nonlinear limit to enable more relaxed dispersion compensation at high optical power compared to the conventional duobinary schemes.The simulation results show chirped duobinary PolSK transmission enlarges the dispersion limited transmission distance, increases the dispersion tolerance and overcome the SPM nonlinear limit.
Khailova, L S; Dedukhova, V I; Mokhova, E N
2008-10-01
It is known that an addition of FeSO4 in the presence of ascorbic acid to cells or mitochondria can injure energy coupling and some other functions in mitochondria. The present study demonstrates that decrease in ascorbate concentration from 4 to 0.2 mM in the presence of the same low concentrations of FeSO4 accelerates the nonspecific pore opening, while cyclosporin A prevents and under some conditions reverses the pore opening. Hydrophobic cations SkQ1 and MitoQ (structural analogs of plastoquinone and coenzyme Q(10), respectively) delay pore opening, SkQ1 being more efficient. It is known that an increase in matrix ADP concentration delays pore opening, while an addition of carboxyatractylate to mitochondria accelerates the beginning of pore opening. Preliminary addition of SkQ1 into a mitochondrial suspension increased the effect of ADP and decreased the effect of carboxyatractylate. These results suggest that under the conditions used SkQ1 protects mitochondria from oxidative damage as an antioxidant when added at extremely low concentrations.
Mitochondria-Targeted Antioxidant SkQ1 Improves Dermal Wound Healing in Genetically Diabetic Mice
Demyanenko, Ilya A.; Zakharova, Vlada V.; Ilyinskaya, Olga P.; Vasilieva, Tamara V.; Fedorov, Artem V.; Skulachev, Vladimir P.
2017-01-01
Oxidative stress is widely recognized as an important factor in the delayed wound healing in diabetes. However, the role of mitochondrial reactive oxygen species in this process is unknown. It was assumed that mitochondrial reactive oxygen species are involved in many wound-healing processes in both diabetic humans and animals. We have applied the mitochondria-targeted antioxidant 10-(6′-plastoquinonyl)decyltriphenylphosphonium (SkQ1) to explore the role of mitochondrial reactive oxygen species in the wound healing of genetically diabetic mice. Healing of full-thickness excisional dermal wounds in diabetic C57BL/KsJ-db−/db− mice was significantly enhanced after long-term (12 weeks) administration of SkQ1. SkQ1 accelerated wound closure and stimulated epithelization, granulation tissue formation, and vascularization. On the 7th day after wounding, SkQ1 treatment increased the number of α-smooth muscle actin-positive cells (myofibroblasts), reduced the number of neutrophils, and increased macrophage infiltration. SkQ1 lowered lipid peroxidation level but did not change the level of the circulatory IL-6 and TNF. SkQ1 pretreatment also stimulated cell migration in a scratch-wound assay in vitro under hyperglycemic condition. Thus, a mitochondria-targeted antioxidant normalized both inflammatory and regenerative phases of wound healing in diabetic mice. Our results pointed to nearly all the major steps of wound healing as the target of excessive mitochondrial reactive oxygen species production in type II diabetes. PMID:28761623
Mitochondria-Targeted Antioxidant SkQ1 Improves Dermal Wound Healing in Genetically Diabetic Mice.
Demyanenko, Ilya A; Zakharova, Vlada V; Ilyinskaya, Olga P; Vasilieva, Tamara V; Fedorov, Artem V; Manskikh, Vasily N; Zinovkin, Roman A; Pletjushkina, Olga Yu; Chernyak, Boris V; Skulachev, Vladimir P; Popova, Ekaterina N
2017-01-01
Oxidative stress is widely recognized as an important factor in the delayed wound healing in diabetes. However, the role of mitochondrial reactive oxygen species in this process is unknown. It was assumed that mitochondrial reactive oxygen species are involved in many wound-healing processes in both diabetic humans and animals. We have applied the mitochondria-targeted antioxidant 10-(6'-plastoquinonyl)decyltriphenylphosphonium (SkQ1) to explore the role of mitochondrial reactive oxygen species in the wound healing of genetically diabetic mice. Healing of full-thickness excisional dermal wounds in diabetic C57BL/KsJ-db - /db - mice was significantly enhanced after long-term (12 weeks) administration of SkQ1. SkQ1 accelerated wound closure and stimulated epithelization, granulation tissue formation, and vascularization. On the 7th day after wounding, SkQ1 treatment increased the number of α -smooth muscle actin-positive cells (myofibroblasts), reduced the number of neutrophils, and increased macrophage infiltration. SkQ1 lowered lipid peroxidation level but did not change the level of the circulatory IL-6 and TNF. SkQ1 pretreatment also stimulated cell migration in a scratch-wound assay in vitro under hyperglycemic condition. Thus, a mitochondria-targeted antioxidant normalized both inflammatory and regenerative phases of wound healing in diabetic mice. Our results pointed to nearly all the major steps of wound healing as the target of excessive mitochondrial reactive oxygen species production in type II diabetes.
Structure–Activity Relationships and Molecular Modeling of Sphingosine Kinase Inhibitors
2013-01-01
The design, synthesis, and evaluation of the potency of new isoform-selective inhibitors of sphingosine kinases 1 and 2 (SK1 and SK2), the enzyme that catalyzes the phosphorylation of d-erythro-sphingosine to produce the key signaling lipid, sphingosine 1-phosphate, are described. Recently, we reported that 1-(4-octylphenethyl)piperidin-4-ol (RB-005) is a selective inhibitor of SK1. Here we report the synthesis of 43 new analogues of RB-005, in which the lipophilic tail, polar headgroup, and linker region were modified to extend the structure–activity relationship profile for this lead compound, which we explain using modeling studies with the recently published crystal structure of SK1. We provide a basis for the key residues targeted by our profiled series and provide further evidence for the ability to discriminate between the two isoforms using pharmacological intervention. PMID:24164513
Krásnik, V; Štefaničková, J; Fabková, J; Bucková, D; Helbich, M
2015-09-01
Diabetic retinopathy (DR) is the second most common microvascular complication and the most common cause of blindness in patients with diabetes mellitus (DM). Despite the ongoing research, the findings of diabetic retinopathy epidemiological and risk factors are, until now, not consistent. More finding may be revealed by epidemiological studies, consistently mapping DR epidemiology under the current possibilities of investigations and treatment of the DM. DIARET SK Study, with 5 000 enrolled patients with diabetes mellitus in the Slovak Republic, is, until now, the largest epidemiological study to set the prevalence of diabetic retinopathy. The primary aim is to establish the prevalence of diabetic retinopathy in patients with diabetes mellitus type I and II, according to the duration of the disease. The secondary aim is to establish prevalence of the different stages of the DR and diabetic macular edema (DME) and analysis of the risk factors influence. Included are patients with DM type I and II regardless to the ocular complications history and the period of DM duration. Each enrolled patient has both complex diabetic and ophthalmic examinations.Projects to establish DR prevalence: Tens of projects concerned with diabetic retinopathy epidemiology with different approaches to establish the prevalence and with different patients population. Results from different studies vary significantly (from 12.3 % to 66.9 %). The results depend on the design of the study and the patients recruitment, used examination methods, specific patients population with regard to the geography, prevalence of risk factors, period of diabetes duration, glycated hemoglobin (HbA1C) level, blood pressure, and is higher in type I diabetic patients. The most accurate results are from population epidemiological studies with well-controlled patient recruitment and uniform complex examination that are similar to the DIARET SK study. The DIARET SK study represents the largest epidemiological study to establish the prevalence of the diabetic retinopathy in patients with DM type I and II. Thanks to the quality design, similar to the already published studies, but with larger number of patients and newest examinations methods, the DIARET SK study has the aspiration to obtain the most accurate up to date data of diabetic retinopathy prevalence and risk factors influence to its outbreak. The patients recruitment started in February 2015. The expected date of patients recruitment termination is in the end of the year 2015, and the data analysis in 2016.
Oechslin, Frank; Daraspe, Jean; Giddey, Marlyse; Moreillon, Philippe; Resch, Grégory
2013-12-01
Beta-hemolytic Streptococcus agalactiae is the leading cause of bacteremia and invasive infections. These diseases are treated with β-lactams or macrolides, but the emergence of less susceptible and even fully resistant strains is a cause for concern. New bacteriophage lysins could be promising alternatives against such organisms. They hydrolyze the bacterial peptidoglycan at the end of the phage cycle, in order to release the phage progeny. By using a bioinformatic approach to screen several beta-hemolytic streptococci, a gene coding for a lysin was identified on a prophage carried by Streptococcus dysgalactiae subsp. equisimilis SK1249. The gene product, named PlySK1249, harbored an original three-domain structure with a central cell wall-binding domain surrounded by an N-terminal amidase and a C-terminal CHAP domain. Purified PlySK1249 was highly lytic and bactericidal for S. dysgalactiae (2-log10 CFU/ml decrease within 15 min). Moreover, it also efficiently killed S. agalactiae (1.5-log10 CFU/ml decrease within 15 min) but not several streptococcal commensal species. We further investigated the activity of PlySK1249 in a mouse model of S. agalactiae bacteremia. Eighty percent of the animals (n = 10) challenged intraperitoneally with 10(6) CFU of S. agalactiae died within 72 h, whereas repeated injections of PlySK1249 (45 mg/kg 3 times within 24 h) significantly protected the mice (P < 0.01). Thus, PlySK1249, which was isolated from S. dysgalactiae, demonstrated high cross-lytic activity against S. agalactiae both in vitro and in vivo. These encouraging results indicated that PlySK1249 might represent a good candidate to be developed as a new enzybiotic for the treatment of systemic S. agalactiae infections.
Silachev, Denis N; Isaev, Nikolay K; Pevzner, Irina B; Zorova, Ljubava D; Stelmashook, Elena V; Novikova, Svetlana V; Plotnikov, Egor Y; Skulachev, Vladimir P; Zorov, Dmitry B
2012-01-01
Many ischemia-induced neurological pathologies including stroke are associated with high oxidative stress. Mitochondria-targeted antioxidants could rescue the ischemic organ by providing specific delivery of antioxidant molecules to the mitochondrion, which potentially suffers from oxidative stress more than non-mitochondrial cellular compartments. Besides direct antioxidative activity, these compounds are believed to activate numerous protective pathways. Endogenous anti-ischemic defense may involve the very powerful neuroprotective agent erythropoietin, which is mainly produced by the kidney in a redox-dependent manner, indicating an important role of the kidney in regulation of brain ischemic damage. The goal of this study is to track the relations between the kidney and the brain in terms of the amplification of defense mechanisms during SkQR1 treatment and remote renal preconditioning and provide evidence that the kidney can generate signals inducing a tolerance to oxidative stress-associated brain pathologies. We used the cationic plastoquinone derivative, SkQR1, as a mitochondria-targeted antioxidant to alleviate the deleterious consequences of stroke. A single injection of SkQR1 before cerebral ischemia in a dose-dependent manner reduces infarction and improves functional recovery. Concomitantly, an increase in the levels of erythropoietin in urine and phosphorylated glycogen synthase kinase-3β (GSK-3β) in the brain was detected 24 h after SkQR1 injection. However, protective effects of SkQR1 were not observed in rats with bilateral nephrectomy and in those treated with the nephrotoxic antibiotic gentamicin, indicating the protective role of humoral factor(s) which are released from functional kidneys. Renal preconditioning also induced brain protection in rats accompanied by an increased erythropoietin level in urine and kidney tissue and P-GSK-3β in brain. Co-cultivation of SkQR1-treated kidney cells with cortical neurons resulted in enchanced phosphorylation of GSK-3β in neuronal cells. The results indicate that renal preconditioning and SkQR1-induced brain protection may be mediated through the release of EPO from the kidney.
NASA Astrophysics Data System (ADS)
Witak, Małgorzata
2016-04-01
The diatom flora in six short cores (length of 10-20 cm) taken from Gdańsk Basin, southern Baltic Sea, was analyzed in order to response of diatoms to environmental changes over the past 100 years. This study is a part of CLISED project (Climate Change Impact on Ecosystem Health - Marine Sediments Indicators) funded from Norway Grants in the Polish-Norwegian Research Programme. Three cores P116, M1 and P1 were retrieved from the Gdańsk Deep region, whereas P104, BMPK10 and P110 were drilled from the shallower part - Gulf of Gdańsk. The sediment cores were dated by 210Pb and represented time interval of AD 1895-2015. In this period an artificial mouth of the Vistula River near Świbno was excavated and riverine waters flowed directly to the Gulf of Gdańsk. Urbanization, progressive industrialization and an increase in the inflow of waste water had a strong influence on ecosystem in the last 120 years. The transport of large amounts of nutrients, organic matter and pollutants by the rivers resulted in environmental degradation of the Gdańsk Basin and its progressive eutrophication in particular. Diatoms, being the major component of algal assemblages, are excellent bioindicators for assessing the state of basin ecosystems. They are usually abundant in marine sediments, diverse and sensitive to numerous environmental variables, including physical (e.g. light, temperature, water transparency) and chemical (e.g. pH, alkalinity, nutrient availability) factors. Changes in nutrients concentrations may lead to substantial transformations in the structure of diatom assemblages. Samples for diatom analyses (ca. 0.3-2.0 g dry sediment) were prepared following the standard procedure for diatom observation under light microscope (Battarbee, 1986). To estimate the concentration of siliceous microfossils per unit weight of dry sediment (absolute abundance), a random settling technique was used (Bodén, 1991). Permanent diatom preparations were mounted in Naphrax® (refractive index nD=1.73). The analysis was performed with a NIKON microscope under a 100× oil immersion objective. The raw counts were transformed to relative abundance of the total frustules counted. The diatoms were divided into groups according to their biotype, salinity, trophy and saproby requirements. The content (in percentage) of all ecological groups were counted in the core. A total of 145 diatom species including varieties and forms representing 53 genera were identified in all samples. The diatom community was strong dominance by small-size planktic euhalobous (Thalassiosira levanderi, Pauliella taeniata) and mesohalobous (Cyclotella choctawhatcheeana) species. They were accompanied by freshwater eutraphentic and pollution-tolerant forms Actinocyclus normanii, Cyclostephanos dubius, Cyclotella atomus, C. caspia, C. meneghiniana, Stephanodiscus hantzschii, S. medius, S. neoastraea and S. parvus. The assemblage structure is a visible evidence of the progressive anthropopressure recorded in the near-bottom sediments of the Gdańsk Basin. Moreover, changes in spatial distribution of diatom anthropogenic assemblage show the close relationship to the distance from mouth of the Vistula River.
Ni, Lisheng; Jensen, Slade O; Ky Tonthat, Nam; Berg, Tracey; Kwong, Stephen M; Guan, Fiona H X; Brown, Melissa H; Skurray, Ronald A; Firth, Neville; Schumacher, Maria A
2009-11-01
Plasmids harbored by Staphylococcus aureus are a major contributor to the spread of bacterial multi-drug resistance. Plasmid conjugation and partition are critical to the dissemination and inheritance of such plasmids. Here, we demonstrate that the ArtA protein encoded by the S. aureus multi-resistance plasmid pSK41 is a global transcriptional regulator of pSK41 genes, including those involved in conjugation and segregation. ArtA shows no sequence homology to any structurally characterized DNA-binding protein. To elucidate the mechanism by which it specifically recognizes its DNA site, we obtained the structure of ArtA bound to its cognate operator, ACATGACATG. The structure reveals that ArtA is representative of a new family of ribbon-helix-helix (RHH) DNA-binding proteins that contain extended, N-terminal basic motifs. Strikingly, unlike most well-studied RHH proteins ArtA binds its cognate operators as a dimer. However, we demonstrate that it is also able to recognize an atypical operator site by binding as a dimer-of-dimers and the extended N-terminal regions of ArtA were shown to be essential for this dimer-of-dimer binding mode. Thus, these data indicate that ArtA is a master regulator of genes critical for both horizontal and vertical transmission of pSK41 and that it can recognize DNA utilizing alternate binding modes.
Ni, Lisheng; Jensen, Slade O.; Ky Tonthat, Nam; Berg, Tracey; Kwong, Stephen M.; Guan, Fiona H. X.; Brown, Melissa H.; Skurray, Ronald A.; Firth, Neville; Schumacher, Maria A.
2009-01-01
Plasmids harbored by Staphylococcus aureus are a major contributor to the spread of bacterial multi-drug resistance. Plasmid conjugation and partition are critical to the dissemination and inheritance of such plasmids. Here, we demonstrate that the ArtA protein encoded by the S. aureus multi-resistance plasmid pSK41 is a global transcriptional regulator of pSK41 genes, including those involved in conjugation and segregation. ArtA shows no sequence homology to any structurally characterized DNA-binding protein. To elucidate the mechanism by which it specifically recognizes its DNA site, we obtained the structure of ArtA bound to its cognate operator, ACATGACATG. The structure reveals that ArtA is representative of a new family of ribbon–helix–helix (RHH) DNA-binding proteins that contain extended, N-terminal basic motifs. Strikingly, unlike most well-studied RHH proteins ArtA binds its cognate operators as a dimer. However, we demonstrate that it is also able to recognize an atypical operator site by binding as a dimer-of-dimers and the extended N-terminal regions of ArtA were shown to be essential for this dimer-of-dimer binding mode. Thus, these data indicate that ArtA is a master regulator of genes critical for both horizontal and vertical transmission of pSK41 and that it can recognize DNA utilizing alternate binding modes. PMID:19759211
Bruno, Gennaro; Cencetti, Francesca; Bernacchioni, Caterina; Donati, Chiara; Blankenbach, Kira Vanessa; Thomas, Dominique; Meyer Zu Heringdorf, Dagmar; Bruni, Paola
2018-05-01
Skeletal muscle tissue retains a remarkable regenerative capacity due to the activation of resident stem cells that in pathological conditions or after tissue damage proliferate and commit themselves into myoblasts. These immature myogenic cells undergo differentiation to generate new myofibers or repair the injured ones, giving a strong contribution to muscle regeneration. Cytokines and growth factors, potently released after tissue injury by leukocytes and macrophages, are not only responsible of the induction of the initial inflammatory response, but can also affect skeletal muscle regeneration. Growth factors exploit sphingosine kinase (SK), the enzyme that catalyzes the production of sphingosine 1-phosphate (S1P), to exert their biological effects in skeletal muscle. In this paper we show for the first time that bradykinin (BK), the leading member of kinin/kallikrein system, is able to induce myogenic differentiation in C2C12 myoblasts. Moreover, evidence is provided that SK1, the specific S1P-transporter spinster homolog 2 (Spns2) and S1P 2 receptor are involved in the action exerted by BK, since pharmacological inhibition/antagonism or specific down-regulation significantly alter BK-induced myogenic differentiation. Moreover, the molecular mechanism initiated by BK involves a rapid translocation of SK1 to plasma membrane, analyzed by time-lapse immunofluorescence analysis. The present study highlights the role of SK1/Spns2/S1P receptor 2 signaling axis in BK-induced myogenic differentiation, thus confirming the crucial involvement of this pathway in skeletal muscle cell biology. Copyright © 2018 Elsevier Inc. All rights reserved.
Polish Version of the Neighbourhood Environment Walkability Scale (NEWS-Poland).
Jaśkiewicz, Michał; Besta, Tomasz
2016-11-04
The characteristics of built environments are the subject of intense consideration in the search for solutions to promote wellbeing and a higher quality of life among the inhabitants of cities. Walkability, defined as the extent to which the built environment is friendly to living and fulfilling the needs of the area, has become an important concept in sustainable urban design, public health and environmental psychology. This study systematically adapted the Neighbourhood Environment Walkability Scale (NEWS) for Poland, and evaluated the construct validity aspects of the adapted version among Polish adults. A total sample of 783 participants from a TriCity (Trójmiasto) agglomeration completed the adapted version of the NEWS. Smaller extracted samples of the participants also completed wellbeing related scales, including self-efficacy, local identity and distance to city centre measures. It was expected that various districts of Gdańsk would differ in terms of walkability. The confirmatory factor analysis showed satisfactory goodness-of-fit statistics and factor loadings corresponding to the proposed original factor structure. According to the predictions, the NEWS subscales correlated with the self-efficacy, local identity and wellbeing related measures. In addition, the comparisons between the neighbourhoods of Gdańsk also showed a predictable pattern of results. Overall, the NEWS demonstrated satisfactory measurement properties, and may be useful in the evaluation of the built environment in Poland.
Reddy, Kamani Sudhir K; Chen, Yen-Chiao; Wu, Chih-Chung; Hsu, Chia-Wei; Chang, Ya-Ching; Chen, Chih-Ming; Yeh, Chen-Yu
2018-01-24
Since their introduction, dye-sensitized solar cells (DSCs) have achieved huge success at a laboratory level. Recently, research is concentrated to visualize large DSC modules at the commercial platform. In that aspect, we have tested structurally simple porphyrin-based dye SK6 and anthracene-based dye CW10 for DSCs application under simulated 1 sun (AM 1.5G) and indoor light sources. These two dyes can be easily synthesized and yet are efficient with cell performances of ca. 5.42% and ca. 5.75% (without coadsorbent/additive) for SK6 and CW10, respectively, under AM 1.5G illumination. The power conversion efficiency (PCE) of SK6 reported in this work is the highest ever reported; this is achieved by optimizing the adsorption of SK6 on TiO 2 photoanode using the most suitable solvent and immersion period. Cosensitization of SK6 with CW10 on TiO 2 surface has boosted cell performance further and achieved PCE of ca. 6.31% under AM 1.5G illumination. Charge-transfer properties of individual and cosensitized devices at TiO 2 /dye/electrolyte interface were examined via electrochemical impedance spectroscopy. To understand the cell performances under ambient light conditions, we soaked individual and cosensitized devices under T5 and light-emitting diode light sources in the range of 300-6000 lx. The PCE of ca. 22.91% under T5 light (6000 lx) with J SC = 0.883 mA cm -2 , V OC = 0.646 V, and FF = 0.749 was noted for the cosensitized device, which equals a power output of 426 μW cm -2 . These results reveal that DSCs made of structurally simple dyes performed efficiently under both 1 sun (AM 1.5G) and indoor light conditions, which is undoubtedly a significant achievement when it comes to a choice of commercial application.
NASA Astrophysics Data System (ADS)
Talbot, Robert M.
2017-12-01
There is a clear need for valid and reliable instrumentation that measures teacher knowledge. However, the process of investigating and making a case for instrument validity is not a simple undertaking; rather, it is a complex endeavor. This paper presents the empirical case of one aspect of such an instrument validation effort. The particular instrument under scrutiny was developed in order to determine the effect of a teacher education program on novice science and mathematics teachers' strategic knowledge (SK). The relationship between novice science and mathematics teachers' SK as measured by a survey and their SK as inferred from observations of practice using a widely used observation protocol is the subject of this paper. Moderate correlations between parts of the observation-based construct and the SK construct were observed. However, the main finding of this work is that the context in which the measurement is made (in situ observations vs. ex situ survey) is an essential factor in establishing the validity of the measurement itself.
Sanchez-Encinales, Viviana; Cozar-Castellano, Irene; Garcia-Ocaña, Adolfo; Perdomo, Germán
2015-12-01
Hepatocyte growth factor (HGF) is a cytokine that increases glucose transport ex vivo in skeletal muscle. The aim of this work was to decipher the impact of whether conditional overexpression of HGF in vivo could improve glucose homeostasis and insulin sensitivity in mouse skeletal muscle. Following tetracyclin administration, muscle HGF levels were augmented threefold in transgenic mice (SK-HGF) compared to control mice without altering plasma HGF levels. In conditions of normal diet, SK-HGF mice showed no differences in body weight, plasma triglycerides, blood glucose, plasma insulin and glucose tolerance compared to control mice. Importantly, obese SK-HGF mice exhibited improved whole-body glucose tolerance independently of changes in body weight or plasma triglyceride levels compared to control mice. This effect on glucose homeostasis was associated with significantly higher (∼80%) levels of phosphorylated protein kinase B in muscles from SK-HGF mice compared to control mice. In conclusion, muscle expression of HGF counteracts obesity-mediated muscle insulin resistance and improves glucose tolerance in mice.
Melanogenesis in dermal melanocytes of Japanese Silky chicken embryos.
Ortolani-Machado, C F; Freitas, P F; Faraco, C D
2009-08-01
The Japanese Silky chicken (SK) shows dermal and visceral hyperpigmentation. This study characterizes ultrastructurally the melanin granules developing in dermal melanocytes of the dorsal skin of SK, in an attempt to better understand the processes of melanogenesis in these permanently ectopic cells. The steps of melanogenesis are similar to those described for epidermal melanocytes, with melanosomes going from stage I to IV but, in SK, the maturation occurs in the cell body, as well as in the cytoplasmic processes. At stage III, the deposition of melanin is cumulative and can aggregate in rounded structures, which combine to turn into the mature granule. The final destiny of mature melanosomes is still unclear, although it was observed that dermal macrophages can accumulate melanin granules in their phagosomes. Even with the close proximity between melanocytes and other dermal cells, the transference of melanosomes was not observed. Our findings indicate that melanogenesis in dermal melanocytes in SK has the same morphological characteristics found in epidermal melanocytes, but the functional aspect still remains to be elucidated.
Montopoli, Monica; Bertin, Riccardo; Chen, Zheng; Bolcato, Jenny; Caparrotta, Laura; Froldi, Guglielmina
2012-12-18
Croton lechleri Mull. Arg. (Euphorbiaceae) is a traditional medicinal plant which produces a red sap, traditionally known as "Sangre de Drago"; it is used in folk medicine externally for wounds, fractures, and haemorrhoids, internally for intestinal and stomach ulcers and also for the empirical cure of cancers. We investigated the effects of Croton lechleri sap and taspine in comparison with taxol and vinblastine on the growth of human cancer cell lines of SK23 (melanoma), LoVo and HT29 (colorectal cancer) using MTT and Trypan blue assays. Further, we studied cell cycle by flow cytometry and detected acetylated-α-tubulin by confocal microscope. Croton lechleri inhibited cell proliferation starting from 1 μg/mL in SK23 cells, whereas 10 times higher concentrations were required for growth inhibition of HT-29 and LoVo cell lines. Also taspine (0.1 μg/mL) inhibited the SK23 and HT29 cell proliferation. Further, assay was assessed on SK23 and HT29 cell lines with 24-48 h treatment with sap and taspine. Both sap and taspine inhibited cancer cell proliferation; taspine showed higher activity on SK23 cells, which was significantly increased after 48 h of SK23 treatment. Using confocal microscopy we observed that Croton lechleri (1 μg/mL) caused a loss of microtubule structure, whereas taspine (0.5 μg/mL) caused an increase in acetylated α-tubulin and a modification of cellular morphology, mainly in SK23 cells. Croton lechleri sap 10 and 50 μg/mL influence cell cycle; 50 μg/mL sap caused a dramatic reduction of cells in G(1)/G(0) and S phases with a great increase of subG(0) cells. The data showed that Croton lechleri and taspine could inhibit cell proliferation with higher potency against melanoma SK23 cells, supporting the empirical use of the sap as anticancer in ethnomedicine and taspine as a possible anticancer agent. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Assessing Students' Accounting Knowledge: A Structural Approach.
ERIC Educational Resources Information Center
Boldt, Margaret N.
2001-01-01
Comparisons of students' representations of financial accounting concepts with the knowledge structures of experts were depicted using Pathfinder networks. This structural approach identified the level of students' understanding of concepts and knowledge gaps that need to be addressed. (SK)
Inhibition of the CSF-1 receptor sensitizes ovarian cancer cells to cisplatin.
Yu, Rong; Jin, Hao; Jin, Congcong; Huang, Xuefeng; Lin, Jinju; Teng, Yili
2018-03-01
Ovarian cancer is one of the most common female malignancies, and cisplatin-based chemotherapy is routinely used in locally advanced ovarian cancer patients. Acquired or de novo cisplatin resistance remains the barrier to patient survival, and the mechanisms of cisplatin resistance are still not well understood. In the current study, we found that colony-stimulating-factor-1 receptor (CSF-1R) was upregulated in cisplatin-resistant SK-OV-3 and CaoV-3 cells. Colony-stimulating-factor-1 receptor knockdown suppressed proliferation and enhanced apoptosis in cisplatin-resistant SK-OV-3 and CaoV-3 cells. However, CSF-1R overexpression had inverse effects. While parental SK-OV-3 and CaoV-3 cells were more resistant to cisplatin after CSF-1R overexpression, CSF-1R knockdown in SK-OV-3 and CaoV-3 cells promoted cisplatin sensitivity. Overexpression and knockdown studies also showed that CSF-1R significantly promoted active AKT and ERK1/2 signalling pathways in cisplatin-resistant cells. Furthermore, a combination of cisplatin and CSF-1R inhibitor effectively inhibited tumour growth in xenografts. Taken together, our results provide the first evidence that CSF-1R inhibition can sensitize cisplatin-refractory ovarian cancer cells. This study may help to increase understanding of the molecular mechanisms underlying cisplatin resistance in tumours. Copyright © 2018 John Wiley & Sons, Ltd.
Koneczny, Inga; Stevens, Jo A A; De Rosa, Anna; Huda, Saif; Huijbers, Maartje G; Saxena, Abhishek; Maestri, Michelangelo; Lazaridis, Konstantinos; Zisimopoulou, Paraskevi; Tzartos, Socrates; Verschuuren, Jan; van der Maarel, Silvère M; van Damme, Philip; De Baets, Marc H; Molenaar, Peter C; Vincent, Angela; Ricciardi, Roberta; Martinez-Martinez, Pilar; Losen, Mario
2017-02-01
Autoimmunity mediated by IgG4 subclass autoantibodies is an expanding field of research. Due to their structural characteristics a key feature of IgG4 antibodies is the ability to exchange Fab-arms with other, unrelated, IgG4 molecules, making the IgG4 molecule potentially monovalent for the specific antigen. However, whether those disease-associated antigen-specific IgG4 are mono- or divalent for their antigens is unknown. Myasthenia gravis (MG) with antibodies to muscle specific kinase (MuSK-MG) is a well-recognized disease in which the predominant pathogenic IgG4 antibody binds to extracellular epitopes on MuSK at the neuromuscular junction; this inhibits a pathway that clusters the acetylcholine (neurotransmitter) receptors and leads to failure of neuromuscular transmission. In vitro Fab-arm exchange-inducing conditions were applied to MuSK antibodies in sera, purified IgG4 and IgG1-3 sub-fractions. Solid-phase cross-linking assays were established to determine the extent of pre-existing and inducible Fab-arm exchange. Functional effects of the resulting populations of IgG4 antibodies were determined by measuring inhibition of agrin-induced AChR clustering in C2C12 cells. To confirm the results, κ/κ, λ/λ and hybrid κ/λ IgG4s were isolated and tested for MuSK antibodies. At least fifty percent of patients had IgG4, but not IgG1-3, MuSK antibodies that could undergo Fab-arm exchange in vitro under reducing conditions. Also MuSK antibodies were found in vivo that were divalent (monospecific for MuSK). Fab-arm exchange with normal human IgG4 did not prevent the inhibitory effect of serum derived MuSK antibodies on AChR clustering in C2C12 mouse myotubes. The results suggest that a considerable proportion of MuSK IgG4 could already be Fab-arm exchanged in vivo. This was confirmed by isolating endogenous IgG4 MuSK antibodies containing both κ and λ light chains, i.e. hybrid IgG4 molecules. These new findings demonstrate that Fab-arm exchanged antibodies are pathogenic. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Soni, Nikul K; Ross, Alastair B; Scheers, Nathalie; Savolainen, Otto I; Nookaew, Intawat; Gabrielsson, Britt G; Sandberg, Ann-Sofie
2016-09-03
Low-grade chronic inflammatory conditions such as ageing, obesity and related metabolic disorders are associated with deterioration of skeletal muscle (SkM). Human studies have shown that marine fatty acids influence SkM function, though the underlying mechanisms of action are unknown. As a model of diet-induced obesity, we fed C57BL/6J mice either a high fat diet (HFD) with purified marine fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (HFD-ED), a HFD with corn oil, or normal mouse chow for 8 weeks; and used transcriptomics to identify the molecular effects of EPA and DHA on SkM. Consumption of ED-enriched HFD modulated SkM metabolism through increased gene expression of mitochondrial β-oxidation and slow-fiber type genes compared with HFD-corn oil fed mice. Furthermore, HFD-ED intake increased nuclear localization of nuclear factor of activated T-cells (Nfatc4) protein, which controls fiber-type composition. This data suggests a role for EPA and DHA in mitigating some of the molecular responses due to a HFD in SkM. Overall, the results suggest that increased consumption of the marine fatty acids EPA and DHA may aid in the prevention of molecular processes that lead to muscle deterioration commonly associated with obesity-induced low-grade inflammation.
Effect of a membrane-targeted sphingosine kinase 1 on cell proliferation and survival
2005-01-01
Numerous extracellular stimuli activate SK1 (sphingosine kinase type 1) to catalyse the production of sphingosine 1-phosphate, a bioactive lipid that functions as both an extracellular ligand for a family of G-protein-linked receptors and as a putative intracellular messenger. Phorbol esters, calcium or immunoglobulin receptors stimulate SK1 by promoting its translocation to the plasma membrane, which brings it into proximity both to its substrate (i.e. sphingosine) and to activating acidic phospholipids (e.g. phosphatidylserine). To evaluate the consequence of SK translocation, we generated an SK1-derivative tagged with a myristoylation sequence (Myr-SK1) on its N-terminus and overexpressed the construct in 3T3-L1 fibroblasts using recombinant retrovirus. Myr-SK1 overexpression increased SK activity by more than 50-fold in crude membranes, while only stimulating cytoplasmic SK activity by 4-fold. In contrast, the overexpression of WT-SK1 (wild-type SK1), as well as that of a construct containing a false myristoylation sequence (A2-Myr-SK1), markedly increased SK activity in both membrane and cytoplasmic compartments. Immunofluorescence confirmed that Myr-SK1 preferentially localized at the plasma membrane, whereas WT-SK1 and A2-Myr-SK1 partitioned in cytoplasmic/perinuclear cellular regions. Surprisingly, Myr-SK1 overexpression significantly decreased the rates of cell proliferation by delaying exit from G0/G1 phase. Moreover, expression of Myr-SK1 but not WT-SK1 or A2-Myr-SK1 protected cells from apoptosis induced by serum withdrawal. Collectively, these findings reveal that altering the subcellular location of SK1 has marked effects on cell function, with plasma membrane-associated SK having a potent inhibitory effect on the G1–S phase transition. PMID:15693752
The structure factor of primes
NASA Astrophysics Data System (ADS)
Zhang, G.; Martelli, F.; Torquato, S.
2018-03-01
Although the prime numbers are deterministic, they can be viewed, by some measures, as pseudo-random numbers. In this article, we numerically study the pair statistics of the primes using statistical-mechanical methods, particularly the structure factor S(k) in an interval M ≤slant p ≤slant M + L with M large, and L/M smaller than unity. We show that the structure factor of the prime-number configurations in such intervals exhibits well-defined Bragg-like peaks along with a small ‘diffuse’ contribution. This indicates that primes are appreciably more correlated and ordered than previously thought. Our numerical results definitively suggest an explicit formula for the locations and heights of the peaks. This formula predicts infinitely many peaks in any non-zero interval, similar to the behavior of quasicrystals. However, primes differ from quasicrystals in that the ratio between the location of any two predicted peaks is rational. We also show numerically that the diffuse part decays slowly as M and L increases. This suggests that the diffuse part vanishes in an appropriate infinite-system-size limit.
Tadayon, Ateke; Jamshidi, Reza; Esmaeili, Akbar
2016-03-30
Extracellular biosynthesis of nanoparticles have many important advantages such as well dispersed in aqueous solutions, low energy requirements, ecofriendly, non-toxic, low-costs and non-flocculate. This technique have shown significant promise as targeted drug delivery applications. In this investigation, for the first time, we examine the efficacy of targeted therapeutic delivery with t-PA and SK immobilized to biosynthesis of nanoparticles (CuNP) by using Streptococcus equi strains isolated from the horses of Iran and their ability to produce metallic nanoparticles. Also we compared them with their chemical synthesis. The S. equi was screened for its ability to produce MNPs. The minimum size and shapes (23-89 nm) are presented in the formation with good dispersion and high stability. Response Surface methodology was applied for the optimized production of biological CuNPs. The growth factors like pH, temperature and incubation time was changed. The optimum conditions to obtain CuNPs were found with the culture conditions of pH 7.5 in 120 h at 35 °C. To determine some of MNPs structural properties UV-vis absorption spectrophotometer, FTIR, XRD and SEM has characterized. The results provided some parameters may impact on the formation of biological MNPs. Lastly, these MNPs were conjugated with t-PA and SK, as a drug carrier. In addition, effective thrombolysis with magnet-guided SiO2CuNPs-tPA-SK is demonstrated in rat embolism model where 18.6% of the regular t-PA dose and 15.78% of SK dose restored and 15-25 min reductions in blood clot lysis time were observed compared with runs with free t-PA and without magnet-guided and using the same drug dosage. The comparison between CuNPs with MNPs shows that thrombolysis had not been directed to the type of magnetic carrier under the magnetic guide. Copyright © 2016 Elsevier B.V. All rights reserved.
Hosseini, R; Benton, D C; Dunn, P M; Jenkinson, D H; Moss, G W
2001-09-01
1. Our aim was to identify the small-conductance Ca(2+)-activated K(+) channel(s) (SK) underlying the apamin-sensitive afterhyperpolarization (AHP) in rat superior cervical ganglion (SCG) neurones. 2. Degenerate oligonucleotide primers designed to the putative calmodulin-binding domain conserved in all mammalian SK channel sequences were employed to detect SK DNA in a cDNA library from rat SCG. Only a single band, corresponding to a fragment of the rSK3 gene, was amplified. 3. Northern blot analysis employing a PCR-generated rSK3 fragment showed the presence of mRNA coding for SK3 in SCG as well in other rat peripheral tissues including adrenal gland and liver. 4. The same rSK3 fragment enabled the isolation of a full-length rSK3 cDNA from the library. Its sequence was closely similar to, but not identical with, that of the previously reported rSK3 gene. 5. Expression of the rSK3 gene in mammalian cell lines (CHO, HEK cells) caused the appearance of a K(+) conductance with SK channel properties. 6. The application of selective SK blocking agents (including apamin, scyllatoxin and newer non-peptidic compounds) showed these homomeric SK3 channels to have essentially the same pharmacological characteristics as the SCG afterhyperpolarization, but to differ from those of homomeric SK1 and SK2 channels. 7. Immunohistochemistry using a rSK3 antipeptide antibody revealed the presence of SK3 protein in the cell bodies and processes of cultured SCG neurones. 8. Taken together, these results identify SK3 as a major component of the SK channels responsible for the afterhyperpolarization of cultured rat SCG neurones.
Unconventional topological Hall effect in skyrmion crystals caused by the topology of the lattice
NASA Astrophysics Data System (ADS)
Göbel, Börge; Mook, Alexander; Henk, Jürgen; Mertig, Ingrid
2017-03-01
The hallmark of a skyrmion crystal (SkX) is the topological Hall effect (THE). In this article we predict and explain an unconventional behavior of the topological Hall conductivity in SkXs. In simple terms, the spin texture of the skyrmions causes an inhomogeneous emergent magnetic field whose associated Lorentz force acts on the electrons. By making the emergent field homogeneous, the THE is mapped onto the quantum Hall effect (QHE). Consequently, each electronic band of the SkX is assigned to a Landau level. This correspondence of THE and QHE allows us to explain the unconventional behavior of the THE of electrons in SkXs. For example, a skyrmion crystal on a triangular lattice exhibits a quantized topological Hall conductivity with steps of 2 .e2/h below and with steps of 1 .e2/h above the van Hove singularity. On top of this, the conductivity shows a prominent sign change at the van Hove singularity. These unconventional features are deeply connected to the topology of the structural lattice.
An, Xiangjie; Xu, Guangfen; Yang, Liu; Wang, Yuejue; Li, Yan; McHepange, Uwesu O; Shen, Guanxin; Tu, Yating; Tao, Juan
2014-01-01
The hypoxia-inducible factor-1 (HIF-1α) pathway is associated with tumor growth, angiogenesis and metastasis in various carcinomas. Little is known regarding the role of the HIF-1α signaling pathway in cutaneous squamous cell carcinoma (SCC). We investigated the expression of HIF-1α, vascular endothelial growth factor (VEGF) and the HIF negative regulator, prolyl hydroxylase domain protein 2 (PHD2), in cutaneous SCC, Bowen's disease, seborrheic keratosis (SK) and normal skin by immunohistochemistry and in situ hybridization. Additionally, we explored the relationships between these factors and the clinical and histological characteristics of each disease. Our study indicated that the expression of HIF-1α and VEGF was significantly higher (P < 0.05) in cutaneous SCC than in Bowen's disease, SK or normal skin. In contrast, PHD2 showed significantly higher expression in normal skin compared with SK, Bowen's disease and cutaneous SCC (P < 0.05). Grade II-IV cutaneous SCC had higher expression levels of nuclear HIF-1α and cytoplasm VEGF protein but less nuclear PHD2 protein than grade Ι cutaneous SCC (P < 0.05). Overexpression of HIF-1α and VEGF, as well as the decreased expression of PHD2, may play important roles in the development of cutaneous SCC. © 2013 Japanese Dermatological Association.
Women and Working Conditions: Prospects for Improvement?
ERIC Educational Resources Information Center
Seguret, Marie-Claire
1983-01-01
Women's difficult working conditions are due to factors such as the nature and form of women's employment, their reproductive role, and family responsibilities. The relative importance of these factors must be assessed in order to redress inequalities. (SK)
Morsch, Marco; Reddel, Stephen W; Ghazanfari, Nazanin; Toyka, Klaus V; Phillips, William D
2013-01-01
In myasthenia gravis, the neuromuscular junction is impaired by the antibody-mediated loss of postsynaptic acetylcholine receptors (AChRs). Muscle weakness can be improved upon treatment with pyridostigmine, a cholinesterase inhibitor, or with 3,4-diaminopyridine, which increases the release of ACh quanta. The clinical efficacy of pyridostigmine is in doubt for certain forms of myasthenia. Here we formally examined the effects of these compounds in the antibody-induced mouse model of anti-muscle-specific kinase (MuSK) myasthenia gravis. Mice received 14 daily injections of IgG from patients with anti-MuSK myasthenia gravis. This caused reductions in postsynaptic AChR densities and in endplate potential amplitudes. Systemic delivery of pyridostigmine at therapeutically relevant levels from days 7 to 14 exacerbated the anti-MuSK-induced structural alterations and functional impairment at motor endplates in the diaphragm muscle. No such effect of pyridostigmine was found in mice receiving control human IgG. Mice receiving smaller amounts of MuSK autoantibodies did not display overt weakness, but 9 days of pyridostigmine treatment precipitated generalised muscle weakness. In contrast, one week of treatment with 3,4-diaminopyridine enhanced neuromuscular transmission in the diaphragm muscle. Both pyridostigmine and 3,4-diaminopyridine increase ACh in the synaptic cleft yet only pyridostigmine potentiated the anti-MuSK-induced decline in endplate ACh receptor density. These results thus suggest that ongoing pyridostigmine treatment potentiates anti-MuSK-induced AChR loss by prolonging the activity of ACh in the synaptic cleft. PMID:23440963
Morsch, Marco; Reddel, Stephen W; Ghazanfari, Nazanin; Toyka, Klaus V; Phillips, William D
2013-05-15
In myasthenia gravis, the neuromuscular junction is impaired by the antibody-mediated loss of postsynaptic acetylcholine receptors (AChRs). Muscle weakness can be improved upon treatment with pyridostigmine, a cholinesterase inhibitor, or with 3,4-diaminopyridine, which increases the release of ACh quanta. The clinical efficacy of pyridostigmine is in doubt for certain forms of myasthenia. Here we formally examined the effects of these compounds in the antibody-induced mouse model of anti-muscle-specific kinase (MuSK) myasthenia gravis. Mice received 14 daily injections of IgG from patients with anti-MuSK myasthenia gravis. This caused reductions in postsynaptic AChR densities and in endplate potential amplitudes. Systemic delivery of pyridostigmine at therapeutically relevant levels from days 7 to 14 exacerbated the anti-MuSK-induced structural alterations and functional impairment at motor endplates in the diaphragm muscle. No such effect of pyridostigmine was found in mice receiving control human IgG. Mice receiving smaller amounts of MuSK autoantibodies did not display overt weakness, but 9 days of pyridostigmine treatment precipitated generalised muscle weakness. In contrast, one week of treatment with 3,4-diaminopyridine enhanced neuromuscular transmission in the diaphragm muscle. Both pyridostigmine and 3,4-diaminopyridine increase ACh in the synaptic cleft yet only pyridostigmine potentiated the anti-MuSK-induced decline in endplate ACh receptor density. These results thus suggest that ongoing pyridostigmine treatment potentiates anti-MuSK-induced AChR loss by prolonging the activity of ACh in the synaptic cleft.
Sutton, Kristin A; Breen, Jennifer; MacDonald, Ulrike; Beanan, Janet M; Olson, Ruth; Russo, Thomas A; Schultz, L Wayne; Umland, Timothy C
2015-08-01
Acinetobacter baumannii is an opportunistic Gram-negative pathogen that is an important cause of healthcare-associated infections exhibiting high mortality rates. Clinical isolates of multidrug-resistant (MDR) and extremely drug-resistant (XDR) A. baumannii strains are increasingly being observed. Compounding this concern is the dearth of new antibacterial agents in late-stage development that are effective against MDR and XDR A. baumannii. As part of an effort to address these concerns, two genes (aroA and aroC) of the shikimate pathway have previously been determined to be essential for the growth and survival of A. baumannii during host infection (i.e. to be essential in vivo). This study expands upon these results by demonstrating that the A. baumannii aroK gene, encoding shikimate kinase (SK), is also essential in vivo in a rat soft-tissue infection model. The crystal structure of A. baumannii SK in complex with the substrate shikimate and a sulfate ion that mimics the binding interactions expected for the β-phosphate of ATP was then determined to 1.91 Å resolution and the enzyme kinetics were characterized. The flexible shikimate-binding domain and LID region are compared with the analogous regions in other SK crystal structures. The impact of structural differences and sequence divergence between SKs from pathogenic bacteria that may influence antibiotic-development efforts is discussed.
Identification and characterization of two wheat Glycogen Synthase Kinase 3/ SHAGGY-like kinases.
Bittner, Thomas; Campagne, Sarah; Neuhaus, Gunther; Rensing, Stefan A; Fischer-Iglesias, Christiane
2013-04-18
Plant Glycogen Synthase Kinase 3/ SHAGGY-like kinases (GSKs) have been implicated in numerous biological processes ranging from embryonic, flower, stomata development to stress and wound responses. They are key regulators of brassinosteroid signaling and are also involved in the cross-talk between auxin and brassinosteroid pathways. In contrast to the human genome that contains two genes, plant GSKs are encoded by a multigene family. Little is known about Liliopsida resp. Poaceae in comparison to Brassicaceae GSKs. Here, we report the identification and structural characterization of two GSK homologs named TaSK1 and TaSK2 in the hexaploid wheat genome as well as a widespread phylogenetic analysis of land plant GSKs. Genomic and cDNA sequence alignments as well as chromosome localization using nullisomic-tetrasomic lines provided strong evidence for three expressed gene copies located on homoeolog chromosomes for TaSK1 as well as for TaSK2. Predicted proteins displayed a clear GSK signature. In vitro kinase assays showed that TaSK1 and TaSK2 possessed kinase activity. A phylogenetic analysis of land plant GSKs indicated that TaSK1 and TaSK2 belong to clade II of plant GSKs, the Arabidopsis members of which are all involved in Brassinosteroid signaling. Based on a single ancestral gene in the last common ancestor of all land plants, paralogs were acquired and retained through paleopolyploidization events, resulting in six to eight genes in angiosperms. More recent duplication events have increased the number up to ten in some lineages. To account for plant diversity in terms of functionality, morphology and development, attention has to be devoted to Liliopsida resp Poaceae GSKs in addition to Arabidopsis GSKs. In this study, molecular characterization, chromosome localization, kinase activity test and phylogenetic analysis (1) clarified the homologous/paralogous versus homoeologous status of TaSK sequences, (2) pointed out their affiliation to the GSK multigene family, (3) showed a functional kinase activity, (4) allowed a classification in clade II, members of which are involved in BR signaling and (5) allowed to gain information on acquisition and retention of GSK paralogs in angiosperms in the context of whole genome duplication events. Our results provide a framework to explore Liliopsida resp Poaceae GSKs functions in development.
Hirata, Maki; Nakajima, Nobuyuki; Saito, Kosuke; Hashimoto, Hiroyuki; Soeda, Shuichi; Uchiyama, Yoshiyasu; Watanabe, Masahiko
2016-01-01
Losses in vital functions of the somatic motor and sensory nervous system are induced by severe long-gap peripheral nerve transection injury. In such cases, autologous nerve grafts are the gold standard treatment, despite the unavoidable sacrifice of other healthy functions, whereas the prognosis is not always favorable. Here, we use human skeletal muscle-derived stem cells (Sk-SCs) to reconstitute the function after long nerve-gap injury. Muscles samples were obtained from the amputated legs from 9 patients following unforeseen accidents. The Sk-SCs were isolated using conditioned collagenase solution, and sorted as CD34+/45- (Sk-34) and CD34-/45-/29+ (Sk-DN/29+) cells. Cells were separately cultured/expanded under optimal conditions for 2 weeks, then injected into the athymic nude mice sciatic nerve long-gap model (7-mm) bridging an acellular conduit. After 8–12 weeks, active cell engraftment was observed only in the Sk-34 cell transplanted group, showing preferential differentiation into Schwann cells and perineurial/endoneurial cells, as well as formation of the myelin sheath and perineurium/endoneurium surrounding regenerated axons, resulted in 87% of numerical recovery. Differentiation into vascular cell lineage (pericyte and endothelial cells) were also observed. A significant tetanic tension recovery (over 90%) of downstream muscles following electrical stimulation of the sciatic nerve (at upper portion of the gap) was also achieved. In contrast, Sk-DN/29+ cells were completely eliminated during the first 4 weeks, but relatively higher numerical (83% vs. 41% in axon) and functional (80% vs. 60% in tetanus) recovery than control were observed. Noteworthy, significant increase in the formation of vascular networks in the conduit during the early stage (first 2 weeks) of recovery was observed in both groups with the expression of key factors (mRNA and protein levels), suggesting the paracrine effects to angiogenesis. These results suggested that the human Sk-SCs may be a practical source for autologous stem cell therapy following severe peripheral nerve injury. PMID:27846318
Tamaki, Tetsuro; Hirata, Maki; Nakajima, Nobuyuki; Saito, Kosuke; Hashimoto, Hiroyuki; Soeda, Shuichi; Uchiyama, Yoshiyasu; Watanabe, Masahiko
2016-01-01
Losses in vital functions of the somatic motor and sensory nervous system are induced by severe long-gap peripheral nerve transection injury. In such cases, autologous nerve grafts are the gold standard treatment, despite the unavoidable sacrifice of other healthy functions, whereas the prognosis is not always favorable. Here, we use human skeletal muscle-derived stem cells (Sk-SCs) to reconstitute the function after long nerve-gap injury. Muscles samples were obtained from the amputated legs from 9 patients following unforeseen accidents. The Sk-SCs were isolated using conditioned collagenase solution, and sorted as CD34+/45- (Sk-34) and CD34-/45-/29+ (Sk-DN/29+) cells. Cells were separately cultured/expanded under optimal conditions for 2 weeks, then injected into the athymic nude mice sciatic nerve long-gap model (7-mm) bridging an acellular conduit. After 8-12 weeks, active cell engraftment was observed only in the Sk-34 cell transplanted group, showing preferential differentiation into Schwann cells and perineurial/endoneurial cells, as well as formation of the myelin sheath and perineurium/endoneurium surrounding regenerated axons, resulted in 87% of numerical recovery. Differentiation into vascular cell lineage (pericyte and endothelial cells) were also observed. A significant tetanic tension recovery (over 90%) of downstream muscles following electrical stimulation of the sciatic nerve (at upper portion of the gap) was also achieved. In contrast, Sk-DN/29+ cells were completely eliminated during the first 4 weeks, but relatively higher numerical (83% vs. 41% in axon) and functional (80% vs. 60% in tetanus) recovery than control were observed. Noteworthy, significant increase in the formation of vascular networks in the conduit during the early stage (first 2 weeks) of recovery was observed in both groups with the expression of key factors (mRNA and protein levels), suggesting the paracrine effects to angiogenesis. These results suggested that the human Sk-SCs may be a practical source for autologous stem cell therapy following severe peripheral nerve injury.
17 CFR 229.1103 - (Item 1103) Transaction summary and risk factors.
Code of Federal Regulations, 2010 CFR
2010-04-01
... summary and risk factors. 229.1103 Section 229.1103 Commodity and Securities Exchanges SECURITIES AND... (Regulation AB) § 229.1103 (Item 1103) Transaction summary and risk factors. (a) Prospectus summary. In... be assigned. (b) Risk factors. In providing the information required by Item 503(c) of Regulation S-K...
17 CFR 229.1103 - (Item 1103) Transaction summary and risk factors.
Code of Federal Regulations, 2011 CFR
2011-04-01
... summary and risk factors. 229.1103 Section 229.1103 Commodity and Securities Exchanges SECURITIES AND... (Regulation AB) § 229.1103 (Item 1103) Transaction summary and risk factors. (a) Prospectus summary. In... be assigned. (b) Risk factors. In providing the information required by Item 503(c) of Regulation S-K...
Grzetic, Douglas J; Delaney, Kris T; Fredrickson, Glenn H
2018-05-28
We derive the effective Flory-Huggins parameter in polarizable polymeric systems, within a recently introduced polarizable field theory framework. The incorporation of bead polarizabilities in the model self-consistently embeds dielectric response, as well as van der Waals interactions. The latter generate a χ parameter (denoted χ̃) between any two species with polarizability contrast. Using one-loop perturbation theory, we compute corrections to the structure factor Sk and the dielectric function ϵ^(k) for a polarizable binary homopolymer blend in the one-phase region of the phase diagram. The electrostatic corrections to S(k) can be entirely accounted for by a renormalization of the excluded volume parameter B into three van der Waals-corrected parameters B AA , B AB , and B BB , which then determine χ̃. The one-loop theory not only enables the quantitative prediction of χ̃ but also provides useful insight into the dependence of χ̃ on the electrostatic environment (for example, its sensitivity to electrostatic screening). The unapproximated polarizable field theory is amenable to direct simulation via complex Langevin sampling, which we employ here to test the validity of the one-loop results. From simulations of S(k) and ϵ^(k) for a system of polarizable homopolymers, we find that the one-loop theory is best suited to high concentrations, where it performs very well. Finally, we measure χ̃N in simulations of a polarizable diblock copolymer melt and obtain excellent agreement with the one-loop theory. These constitute the first fully fluctuating simulations conducted within the polarizable field theory framework.
Searching for the Final Answer: Factors Contributing to Medication Administration Errors.
ERIC Educational Resources Information Center
Pape, Tess M.
2001-01-01
Causal factors contributing to errors in medication administration should be thoroughly investigated, focusing on systems rather than individual nurses. Unless systemic causes are addressed, many errors will go unreported for fear of reprisal. (Contains 42 references.) (SK)
Social and Historical Factors in the Development of Swedish Adult Education.
ERIC Educational Resources Information Center
Christie, Michael F.
2002-01-01
Depicts the history of adult education in Sweden over the last 4 centuries, outlining factors that influenced development of its well-resourced infrastructure. Discusses politics, religious influences, industrialization, folk high schools, temperance societies, and workers' education. (SK)
Cole, R N; Ghazanfari, N; Ngo, S T; Gervásio, O L; Reddel, S W; Phillips, W D
2010-01-01
The postsynaptic muscle-specific kinase (MuSK) coordinates formation of the neuromuscular junction (NMJ) during embryonic development. Here we have studied the effects of MuSK autoantibodies upon the NMJ in adult mice. Daily injections of IgG from four MuSK autoantibody-positive myasthenia gravis patients (MuSK IgG; 45 mg day−1i.p. for 14 days) caused reductions in postsynaptic ACh receptor (AChR) packing as assessed by fluorescence resonance energy transfer (FRET). IgG from the patients with the highest titres of MuSK autoantibodies caused large (51–73%) reductions in postsynaptic MuSK staining (cf. control mice; P < 0.01) and muscle weakness. Among mice injected for 14 days with control and MuSK patient IgGs, the residual level of MuSK correlated with the degree of impairment of postsynaptic AChR packing. However, the loss of postsynaptic MuSK preceded this impairment of postsynaptic AChR. When added to cultured C2 muscle cells the MuSK autoantibodies caused tyrosine phosphorylation of MuSK and the AChR β-subunit, and internalization of MuSK from the plasma membrane. The results suggest a pathogenic mechanism in which MuSK autoantibodies rapidly deplete MuSK from the postsynaptic membrane leading to progressive dispersal of postsynaptic AChRs. Moreover, maintenance of postsynaptic AChR packing at the adult NMJ would appear to depend upon physical engagement of MuSK with the AChR scaffold, notwithstanding activation of the MuSK-rapsyn system of AChR clustering. PMID:20603331
Kakitsuba, Naoshi
2016-07-01
Four hypothetical thermophysiological responses to changes in relative humidity (Rh) under thermally neutral, warm, and hot conditions were proposed for a person at rest. Under thermally neutral and warm conditions, the first hypothetical response to an increase in Rh was a decrease in mean skin temperature (T¯sk) due to increase in mean evaporation rate (E¯sk), and the second hypothetical response to a decrease in Rh was a decrease, an increase, or no change in T¯sk, depending on changes in the E¯sk. Under hot conditions, the third hypothetical response to an increase in the Rh was an increase in T¯sk or decrease in T¯sk upon decrease in the Rh due to changes in E¯sk, and the forth hypothetical response to an increase in Rh was an increase in T¯sk due to increase in the peripheral blood flow rate (SkBF). To test these hypotheses, the T¯sk and E¯sk of four young male volunteers were measured at 28°C, 30°C, or 32°C while the Rh was maintained at 40% or 80% Rh for 60min after 20min exposure at 60% Rh (control condition). In a second experiment, the T¯sk, E¯sk, and SkBF of five young male volunteers were measured at 34°C-40% Rh or 36°C-40% Rh, or 34°C-70% Rh or 36°C-70% Rh for 60min after 20min exposure at 28°C-60% Rh (control condition). The first hypothesis was partly supported by the findings that the T¯sk was lower than the control values at 28°C-80% Rh and the E¯sk was higher than the control values at 80% Rh at any tested temperature. The second hypothesis was partly supported by the findings that the T¯sk was lower than the control values at 28°C-40% Rh, and there were small changes in both T¯sk and E¯sk at 30°C-40% Rh. The third and fourth hypotheses were supported by the findings that the T¯sk at 36°C-70% Rh was significantly higher (p<0.01) than at 36°C-40% Rh, the E¯sk was significantly higher (p<0.01) at 70% Rh than at 40% Rh, and SkBF was positively correlated with T¯sk. Copyright © 2016 Elsevier Ltd. All rights reserved.
Wang, Ruisi; Ding, Qian; Yaqoob, Usman; de Assuncao, Thiago M.; Verma, Vikas K.; Hirsova, Petra; Cao, Sheng; Mukhopadhyay, Debabrata; Huebert, Robert C.; Shah, Vijay H.
2015-01-01
Exosomes are cell-derived extracellular vesicles thought to promote intercellular communication by delivering specific content to target cells. The aim of this study was to determine whether endothelial cell (EC)-derived exosomes could regulate the phenotype of hepatic stellate cells (HSCs). Initial microarray studies showed that fibroblast growth factor 2 induced a 2.4-fold increase in mRNA levels of sphingosine kinase 1 (SK1). Exosomes derived from an SK1-overexpressing EC line increased HSC migration 3.2-fold. Migration was not conferred by the dominant negative SK1 exosome. Incubation of HSCs with exosomes was also associated with an 8.3-fold increase in phosphorylation of AKT and 2.5-fold increase in migration. Exosomes were found to express the matrix protein and integrin ligand fibronectin (FN) by Western blot analysis and transmission electron microscopy. Blockade of the FN-integrin interaction with a CD29 neutralizing antibody or the RGD peptide attenuated exosome-induced HSC AKT phosphorylation and migration. Inhibition of endocytosis with transfection of dynamin siRNA, the dominant negative dynamin GTPase construct Dyn2K44A, or the pharmacological inhibitor Dynasore significantly attenuated exosome-induced AKT phosphorylation. SK1 levels were increased in serum exosomes derived from mice with experimental liver fibrosis, and SK1 mRNA levels were up-regulated 2.5-fold in human liver cirrhosis patient samples. Finally, S1PR2 inhibition protected mice from CCl4-induced liver fibrosis. Therefore, EC-derived SK1-containing exosomes regulate HSC signaling and migration through FN-integrin-dependent exosome adherence and dynamin-dependent exosome internalization. These findings advance our understanding of EC/HSC cross-talk and identify exosomes as a potential target to attenuate pathobiology signals. PMID:26534962
Wang, Ruisi; Ding, Qian; Yaqoob, Usman; de Assuncao, Thiago M; Verma, Vikas K; Hirsova, Petra; Cao, Sheng; Mukhopadhyay, Debabrata; Huebert, Robert C; Shah, Vijay H
2015-12-25
Exosomes are cell-derived extracellular vesicles thought to promote intercellular communication by delivering specific content to target cells. The aim of this study was to determine whether endothelial cell (EC)-derived exosomes could regulate the phenotype of hepatic stellate cells (HSCs). Initial microarray studies showed that fibroblast growth factor 2 induced a 2.4-fold increase in mRNA levels of sphingosine kinase 1 (SK1). Exosomes derived from an SK1-overexpressing EC line increased HSC migration 3.2-fold. Migration was not conferred by the dominant negative SK1 exosome. Incubation of HSCs with exosomes was also associated with an 8.3-fold increase in phosphorylation of AKT and 2.5-fold increase in migration. Exosomes were found to express the matrix protein and integrin ligand fibronectin (FN) by Western blot analysis and transmission electron microscopy. Blockade of the FN-integrin interaction with a CD29 neutralizing antibody or the RGD peptide attenuated exosome-induced HSC AKT phosphorylation and migration. Inhibition of endocytosis with transfection of dynamin siRNA, the dominant negative dynamin GTPase construct Dyn2K44A, or the pharmacological inhibitor Dynasore significantly attenuated exosome-induced AKT phosphorylation. SK1 levels were increased in serum exosomes derived from mice with experimental liver fibrosis, and SK1 mRNA levels were up-regulated 2.5-fold in human liver cirrhosis patient samples. Finally, S1PR2 inhibition protected mice from CCl4-induced liver fibrosis. Therefore, EC-derived SK1-containing exosomes regulate HSC signaling and migration through FN-integrin-dependent exosome adherence and dynamin-dependent exosome internalization. These findings advance our understanding of EC/HSC cross-talk and identify exosomes as a potential target to attenuate pathobiology signals. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.
Chen, Ruichuan; Liu, Min; Li, Huan; Xue, Yuhua; Ramey, Wanichaya N.; He, Nanhai; Ai, Nanping; Luo, Haohong; Zhu, Ying; Zhou, Nan; Zhou, Qiang
2008-01-01
The positive transcription elongation factor b (P-TEFb), consisting of Cdk9 and cyclin T, stimulates RNA polymerase II elongation and cotranscriptional pre-mRNA processing. To accommodate different growth conditions and transcriptional demands, a reservoir of P-TEFb is kept in an inactive state in the multisubunit 7SK snRNP. Under certain stress or disease conditions, P-TEFb is released to activate transcription, although the signaling pathway(s) that controls this is largely unknown. Here, through analyzing the UV- or hexamethylene bisacetamide (HMBA)-induced release of P-TEFb from 7SK snRNP, an essential role for the calcium ion (Ca2+)–calmodulin–protein phosphatase 2B (PP2B) signaling pathway is revealed. However, Ca2+ signaling alone is insufficient, and PP2B must act sequentially and cooperatively with protein phosphatase 1α (PP1α) to disrupt 7SK snRNP. Activated by UV/HMBA and facilitated by a PP2B-induced conformational change in 7SK snRNP, PP1α releases P-TEFb through dephosphorylating phospho-Thr186 in the Cdk9 T-loop. This event is also necessary for the subsequent recruitment of P-TEFb by the bromodomain protein Brd4 to the preinitiation complex, where Cdk9 remains unphosphorylated and inactive until after the synthesis of a short RNA. Thus, through cooperatively dephosphorylating Cdk9 in response to Ca2+ signaling, PP2B and PP1α alter the P-TEFb functional equilibrium through releasing P-TEFb from 7SK snRNP for transcription. PMID:18483222
Jhou, Bo-Yi; Song, Tuzz-Ying; Lee, Inn; Hu, Miao-Lin; Yang, Nae-Cherng
2017-08-16
NADPH oxidase 4 (NOX4), with the sole function to produce reactive oxygen species (ROS), can be a molecular target for disrupting cancer metastasis. Several studies have indicated that lycopene exhibited anti-metastatic actions in vitro and in vivo. However, the role of NOX4 in the anti-metastatic action of lycopene remains unknown. Herein, we first confirmed the anti-metastatic effect of lycopene (0.1-5 μM) on human liver adenocarcinoma SK-Hep-1 cells. We showed that lycopene significantly inhibited NOX4 protein expression, with the strongest inhibition of 64.3 ± 10.2% (P < 0.05) at 2.5 μM lycopene. Lycopene also significantly inhibited NOX4 mRNA expression, NOX activity, and intracellular ROS levels in SK-Hep-1 cells. We then determined the effects of lycopene on transforming growth factor β (TGF-β)-induced metastasis. We found that TGF-β (5 ng/mL) significantly increased migration, invasion, and adhesion activity, the intracellular ROS level, matrix metalloproteinase 9 (MMP-9) and MMP-2 activities, the level of NOX4 protein expression, and NOX activity. All these TGF-β-induced effects were antagonized by the incubation of SK-Hep-1 cells with lycopene (2.5 μM). Using transient transfection of siRNA against NOX4, we found that the downregulation of NOX4 could mimic lycopene by inhibiting cell migration and the activities of MMP-9 and MMP-2 during the incubation with or without TGF-β on SK-Hep-1 cells. The results demonstrate that the downregulation of NOX4 plays a crucial role in the anti-metastatic action of lycopene in SK-Hep-1 cells.
Alam, Mohammad Sayed; Nam, Young-Joo; Lee, Dong-Ung
2013-11-01
In the present study, a series of (Z)-2,3-diphenylacrylonitrile analogs were synthesized and then evaluated in terms of their cytotoxic activities against four human cancer cell lines, e.g. lung cancer (A549), ovarian cancer (SK-OV-3), skin cancer (SK-MEL-2), and colon cancer (HCT15), as well as anti-microbial activities against three microbes, e.g. Staphylococcus aureus, Salmonella typhi, and Aspergillus niger. The title compounds were synthesized by Knoevenagel condensation reaction of benzyl cyanide or p-nitrobenzyl cyanide with substituted benzaldehydes in good yields. Most of the compounds exhibited significant suppressive activities against the growth of all cancer cell lines. Compound 3c was most active in inhibiting the growth of A549, SK-OV-3, SK-MEL-2, and HCT15 cells lines with IC50 values of 0.57, 0.14, 0.65, and 0.34 mg/mL, respectively, followed by compounds 3f, 3i, and 3h. Compound 3c exhibited 2.4 times greater cytotoxic activity against HCT15 cells, whereas it showed similar potency against SK-OV-3 cells to that of the standard anti-cancer agent doxorubicin. Structure-activity relationship study revealed that electron-donating groups at the para-position of phenyl ring B were more favorable for improved cytotoxic activity, whereas the presence of electron-withdrawing groups was unfavorable compare to unsubstituted acrylonitrile. An optimal electron density on phenyl ring A of (Z)-2,3-diphenylacrylonitrile analogs was crucial for their cytotoxic activities against human cancer cell lines used in the present study. Qualitative structure-cytotoxic activity relationships were studied using physicochemical parameters; a good correlation between calculated polar surface area (PSA), a lipophobic parameter, and cytotoxic activity was found. Moreover, all compounds showed significant anti-bacterial activities against S. typhi, whereas compound 3k showed potent inhibition against both S. aureus and S. typhi bacterial strains. Copyright © 2013 Elsevier Masson SAS. All rights reserved.
Alazami, Anas M; Al-Owain, Mohammad; Alzahrani, Fatema; Shuaib, Taghreed; Al-Shamrani, Hussain; Al-Falki, Yahya H; Al-Qahtani, Saleh M; Alsheddi, Tarfa; Colak, Dilek; Alkuraya, Fowzan S
2012-10-01
Primordial dwarfism (PD) is a clinically and genetically heterogeneous condition. Various molecular mechanisms are known to underlie the disease including impaired mitotic mechanics, abnormal IGF2 expression, perturbed DNA damage response, defective spliceosomal machinery, and abnormal replication licensing. Here, we describe a syndromic form of PD associated with severe intellectual disability and distinct facial features in a large multiplex Saudi family. Analysis reveals a novel underlying mechanism for PD involving depletion of 7SK, an abundant cellular noncoding RNA (ncRNA), due to mutation of its chaperone LARP7. We show that 7SK levels are tightly linked to LARP7 expression across cell lines, and that this chaperone is ubiquitously expressed in the mouse embryo. The 7SK is known to influence the expression of a wide array of genes through its inhibitory effect on the positive transcription elongation factor b (P-TEFb) as well as its competing role in HMGA1-mediated transcriptional regulation. This study documents a critical role played by ncRNA in human development and adds to the growing list of molecular mechanisms that, when perturbed, converge on the PD phenotype. © 2012 Wiley Periodicals, Inc.
Sun, Hongmin; Xu, Yuanxi; Sitkiewicz, Izabela; Ma, Yibao; Wang, Xixi; Yestrepsky, Bryan D; Huang, Yuping; Lapadatescu, Martian C; Larsen, Martha J; Larsen, Scott D; Musser, James M; Ginsburg, David
2012-02-28
The widespread occurrence of antibiotic resistance among human pathogens is a major public health problem. Conventional antibiotics typically target bacterial killing or growth inhibition, resulting in strong selection for the development of antibiotic resistance. Alternative therapeutic approaches targeting microbial pathogenicity without inhibiting growth might minimize selection for resistant organisms. Compounds inhibiting gene expression of streptokinase (SK), a critical group A streptococcal (GAS) virulence factor, were identified through a high-throughput, growth-based screen on a library of 55,000 small molecules. The lead compound [Center for Chemical Genomics 2979 (CCG-2979)] and an analog (CCG-102487) were confirmed to also inhibit the production of active SK protein. Microarray analysis of GAS grown in the presence of CCG-102487 showed down-regulation of a number of important virulence factors in addition to SK, suggesting disruption of a general virulence gene regulatory network. CCG-2979 and CCG-102487 both enhanced granulocyte phagocytosis and killing of GAS in an in vitro assay, and CCG-2979 also protected mice from GAS-induced mortality in vivo. These data suggest that the class of compounds represented by CCG-2979 may be of therapeutic value for the treatment of GAS and potentially other gram-positive infections in humans.
Singh, R R P; Young, A P
2017-08-01
We study the ±J transverse-field Ising spin-glass model at zero temperature on d-dimensional hypercubic lattices and in the Sherrington-Kirkpatrick (SK) model, by series expansions around the strong-field limit. In the SK model and in high dimensions our calculated critical properties are in excellent agreement with the exact mean-field results, surprisingly even down to dimension d=6, which is below the upper critical dimension of d=8. In contrast, at lower dimensions we find a rich singular behavior consisting of critical and Griffiths-McCoy singularities. The divergence of the equal-time structure factor allows us to locate the critical coupling where the correlation length diverges, implying the onset of a thermodynamic phase transition. We find that the spin-glass susceptibility as well as various power moments of the local susceptibility become singular in the paramagnetic phase before the critical point. Griffiths-McCoy singularities are very strong in two dimensions but decrease rapidly as the dimension increases. We present evidence that high enough powers of the local susceptibility may become singular at the pure-system critical point.
NASA Astrophysics Data System (ADS)
Singh, R. R. P.; Young, A. P.
2017-08-01
We study the ±J transverse-field Ising spin-glass model at zero temperature on d -dimensional hypercubic lattices and in the Sherrington-Kirkpatrick (SK) model, by series expansions around the strong-field limit. In the SK model and in high dimensions our calculated critical properties are in excellent agreement with the exact mean-field results, surprisingly even down to dimension d =6 , which is below the upper critical dimension of d =8 . In contrast, at lower dimensions we find a rich singular behavior consisting of critical and Griffiths-McCoy singularities. The divergence of the equal-time structure factor allows us to locate the critical coupling where the correlation length diverges, implying the onset of a thermodynamic phase transition. We find that the spin-glass susceptibility as well as various power moments of the local susceptibility become singular in the paramagnetic phase before the critical point. Griffiths-McCoy singularities are very strong in two dimensions but decrease rapidly as the dimension increases. We present evidence that high enough powers of the local susceptibility may become singular at the pure-system critical point.
ERIC Educational Resources Information Center
Zaslow, Ruth
1991-01-01
Managers can coach employees in writing better reports by helping them through the following steps: audience and purpose, idea generation, organization, drafting, and editing for style, structure, and mechanics. (SK)
Cescutti, P; Paoletti, S
1994-02-15
The specificity of the endoglycanase associated with the bacteriophage phi SK1 particles was tested on the native capsular polysaccharide produced by Klebsiella pneumoniae serotype SK1 and on three chemically modified polymers derived from it. The primary structure of the SK1 capsular polysaccharide is: [formula: see text] and the beta 1-3 linkage between the glucose and the galactose residues is the one cleaved by the phage enzyme. The enzyme activity was assayed on the deacetylated polysaccharide and on two derivatives obtained by removal of both the side-chain sugars and of only the alpha-D-galactosyl unit, respectively. The endoglycanase was more active on the deacetylated polysaccharide than on the native one, suggesting that the presence of the acetyl groups interferes with the enzyme-polysaccharide interaction. A possible role of the acetyl groups in the control of the polysaccharide chain length and hence on the rheological behaviour of the capsule cannot be ruled out, as already indicated for other bacterial polysaccharides. On the contrary, the removal of the side chains, either complete or selective, caused the modification of the recognition site in such a way that the enzymatic depolymerization no longer occurred. Therefore, it can be inferred that the phi SK1 endoglycanase requires the presence of both the side chain sugars to exhibit its cleaving activity, although this latter is in the main chain.
Hancock, Jane M; Weatherall, Kate L; Choisy, Stéphanie C; James, Andrew F; Hancox, Jules C; Marrion, Neil V
2015-05-01
Activation of small conductance calcium-activated potassium (SK) channels is proposed to contribute to repolarization of the action potential in atrial myocytes. This role is controversial, as these cardiac SK channels appear to exhibit an uncharacteristic pharmacology. The objectives of this study were to resolve whether activation of SK channels contributes to atrial action potential repolarization and to determine the likely subunit composition of the channel. The effect of 2 SK channel inhibitors was assessed on outward current evoked in voltage clamp and on action potential duration in perforated patch and whole-cell current clamp recording from acutely isolated mouse atrial myocytes. The presence of SK channel subunits was assessed using immunocytochemistry. A significant component of outward current was reduced by the SK channel blockers apamin and UCL1684. Block by apamin displayed a sensitivity indicating that this current was carried by homomeric SK2 channels. Action potential duration was significantly prolonged by UCL1684, but not by apamin. This effect was accompanied by an increase in beat-to-beat variability and action potential triangulation. This pharmacology was matched by that of expressed heteromeric SK2-SK3 channels in HEK293 cells. Immunocytochemistry showed that atrial myocytes express both SK2 and SK3 channels with an overlapping expression pattern. Only proposed heteromeric SK2-SK3 channels are physiologically activated to contribute to action potential repolarization, which is indicated by the difference in pharmacology of evoked outward current and prolongation of atrial action potential duration. The effect of blocking this channel on the action potential suggests that SK channel inhibition during cardiac function has the potential to be proarrhythmic. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.
Crespi, F
2009-07-24
The family of calcium-activated slow-potassium (SK) channels comprises 3 members, the SK1, SK2 and SK3 channels, all expressed in neurons, known to mediate the slow-afterhyperpolarization occurring after action potentials. In rats, the SK2 and SK3 channels are expressed in the ascending monoaminergic systems, in particular in the serotonin (5-HT) neurons of the raphe dorsalis nucleus (RDN). In mammals the amygdala, a limbic structure involved in the control of emotion and mood, receives 5-HT-containing projections originating in the RDN. The aim of the present study was to investigate the role of SK channels in mediating the release of 5-HT in the amygdala. Apamin, a polypeptiditic compound with SK2-SK3 channel selectivity, was used to block the channels. A dual probing methodology with Nafion coated carbon-fiber micro-electrode (Nafion-mCFE) was implemented to measure concomitantly the extracellular levels of 5-HT in the amygdala and the firing rate of 5-HT neurons in the RDN of anesthetized rats. Subcutaneous administration of apamin increased both the extracellular 5-HT levels in the amygdala and the firing rate of RDN neurons at doses as low as 12.5 microg. The recorded RDN neurons were of 5-HT phenotype, according to electrophysiologic signature and to the effects observed with peripheral administration of 8-hydroxy-2-(d-n-propyl-amino) tetralin (8-OH-DPAT) a 5-HT(1A) agonist known to selectively reduce the firing of 5-HT neurons in RDN. Increases of extracellular 5-HT levels in the amygdala were also seen when apamin was microinjected into the RDN, suggesting a role for 5-HT neurons of the RDN as target for subcutaneously administered apamin. The confirmation of the involvement of 5-HT neurons projecting from RDN to the amygdala in mediating the effects of apamin was obtained by micro-infusion of tetradotoxine into the bundle of 5-HT ascending fibers located in the region of the posterior amygdala. Attenuation of 5-HT release in the amygdala was observed in presence of increased firing of 5-HT neurons of the RDN. In conclusion, the dual CFE micro-sensor probing approach was used to show that apamin increases 5-HT release in the amygdala by increasing the firing rate of 5-HT neurons in RDN.
ERIC Educational Resources Information Center
Raghuram, Sumita; Wiesenfeld, Batia; Garud, Raghu
2003-01-01
Responses from 31.5% of 723 telecommuters revealed a positive association between self-efficacy and both adjustment to teleworking and behaviors for structuring work. The more extensive the telecommuting, the stronger these positive relationships. Women were more proactive in structuring work behavior. (Contains 43 references.) (SK)
ERIC Educational Resources Information Center
Geber, Beverly
1990-01-01
Demographic trends imply that organizations must learn to manage a diverse work force. Ways to change organizational systems, structures, and practices to eliminate subtle barriers are awareness training, attitude change, and valuing diversity. (SK)
MuSK induced experimental autoimmune myasthenia gravis does not require IgG1 antibody to MuSK.
Küçükerden, Melike; Huda, Ruksana; Tüzün, Erdem; Yılmaz, Abdullah; Skriapa, Lamprini; Trakas, Nikos; Strait, Richard T; Finkelman, Fred D; Kabadayı, Sevil; Zisimopoulou, Paraskevi; Tzartos, Socrates; Christadoss, Premkumar
2016-06-15
Sera of myasthenia gravis (MG) patients with muscle-specific receptor kinase-antibody (MuSK-Ab) predominantly display the non-complement fixing IgG4 isotype. Similarly, mouse IgG1, which is the analog of human IgG4, is the predominant isotype in mice with experimental autoimmune myasthenia gravis (EAMG) induced by MuSK immunization. The present study was performed to determine whether IgG1 anti-MuSK antibody is required for immunized mice to develop EAMG. Results demonstrated a significant correlation between clinical severity of EAMG and levels of MuSK-binding IgG1+, IgG2+ and IgG3+ peripheral blood B cells in MuSK-immunized wild-type (WT) mice. Moreover, MuSK-immunized IgG1 knockout (KO) and WT mice showed similar EAMG severity, serum MuSK-Ab levels, muscle acetylcholine receptor concentrations, neuromuscular junction immunoglobulin and complement deposit ratios. IgG1 and IgG3 were the predominant anti-MuSK isotypes in WT and IgG1 KO mice, respectively. These observations demonstrate that non-IgG1 isotypes can mediate MuSK-EAMG pathogenesis. Copyright © 2016 Elsevier B.V. All rights reserved.
Aging as Evolution-Facilitating Program and a Biochemical Approach to Switch It Off
NASA Astrophysics Data System (ADS)
Skulachev, Vladimir P.
A concept is presented considering aging of living organisms as a final step of their ontogenetic program. It is assumed that such an aging program was invented by biological evolution to facilitate the evolutionary process. Indications are summarized suggesting that controlled production of toxic forms of oxygen (so called reactive oxygen species) by respiring intracellular organelles (mitochondria) is an obligatory component of the aging program. First results of a research project devoted to an attempt to interrupt aging program by antioxidants specifically addressed to mitochondria have been described. Within the framework of the project, antioxidants of a new type (SkQ) were synthesized. SkQs are composed of (i) plastoquinone (an antioxidant moiety), (ii) a penetrating cation, and (iii) a decane or pentane linker. Using planar bilayer phospholipid membranes, we selected SkQ derivatives of the highest penetrability, namely plastoquinonyl decyl triphenylphosphonium (SkQ1), plastoquinonyl decyl rhodamine 19 (SkQR1), and methylplastoquinonyl decyl triphenylphosphonium (SkQ3). Anti- and prooxidant properties of these substances and also of ubiquinonyl-decyl-triphenylphosphonium (MitoQ) were tested in isolated mitochondria. Micromolar concentrations of cationic quinones are found to be very strong prooxidants, but in the lower (sub-micromolar) concentrations they display antioxidant activity which decreases in the series SkQ1 = SkQR1 > SkQ3 > MitoQ. Thus, the window between the anti- and prooxidant effects is the smallest for MitoQ and the largest for SkQ1 and SkQR1. SkQ1 is rapidly reduced by complex III of the mitochondrial respiratory chain, i.e. it is a rechargeable antioxidant. Extremely low concentrations of SkQ1 and SkQR1 completely arrest the H2O2-induced apoptosis in human fibroblasts and HeLa cells (for SkQ1, C 1/2 = 8 · 10-9M). Higher concentrations of SkQ1 are required to block necrosis initiated by reactive oxygen species (ROS). In mice, SkQ1 decelerates the development of three types of accelerated aging (progeria) and also of normal aging, and this effect is especially demonstrative at early stages of aging. The same pattern is shown in invertebrates (Drosophila and Daphnia), and fungus (Podospora anserina). In mammals, the effect of SkQs on aging is accompanied by inhibition of development of such age-related diseases as osteoporosis, involution of thymus, cataract, retinopathy, etc. SkQ1 manifests a strong therapeutic action on some already pronounced retinopathies, in particular, congenital retinal dysplasia. With drops containing 250 nM SkQ1, vision is recovered in 66 of 96 animals (dogs, cats and horses) who became blind because of retinopathy. SkQ1-containing drops instilled into eyes prevent the loss of sight in rabbits suffering from experimental uveitis and restore vision to animals that had already become blind due to this pathology. A favorable effect is also achieved in experimental glaucoma in rabbits. Moreover, the pretreatment of rats with 0.2 nM SkQ1 significantly decreases the H2O2-induced arrhythmia of the isolated heart. SkQ1 strongly reduces the damaged area in myocardial infarction or stroke and prevents the death of animals from kidney infarction. In p53-/- mice, SkQ1 decreases the ROS level in the spleen cells and inhibits appearance of lymphomas which are the main cause of death of such animals. As a result, the lifespan increases. SkQs look like promising drugs to treat aging and age-related diseases.
Transport properties of liquid metal hydrogen under high pressures
NASA Technical Reports Server (NTRS)
Brown, R. C.; March, N. H.
1972-01-01
A theory is developed for the compressibility and transport properties of liquid metallic hydrogen, near to its melting point and under high pressure. The interionic force law is assumed to be of the screened Coulomb type, because hydrogen has no core electrons. The random phase approximation is used to obtain the structure factor S(k) of the system in terms of the Fourier transform of this force law. The long wavelenth limit of the structure factor S(o) is related to the compressibility, which is much lower than that of alkali metals at their melting points. The diffusion constant at the melting point is obtained in terms of the Debye frequency, using a frequency spectrum analogous with the phonon spectrum of a solid. A similar argument is used to obtain the combined shear and bulk viscosities, but these depend also on S(o). The transport coefficients are found to be about the same size as those of alkali metals at their melting points.
Gaballah, Mohammad A; Ahmed, Rehab-Allah
2015-12-01
The distinction between cutaneous basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and seborrheic keratosis (SK), which are common entities in clinical practice, can be difficult clinically and histologically. CD10 and Bcl2 antigens are important factors in tumor growth, survival and spread. The aim of the present study is to define the frequency of CD10 and Bcl2 expression in such cutaneous tumors and its relation to the clinicopathological characteristics as well as their possible diagnostic utility. CD10 and Bcl2 immunohistochemistry was performed on 30 BCC, 20 SCC and 15 SK. 93.3% of SK cases and 53.3% of BCC cases showed significant expression of CD10 in tumor cells when compared either with each other or with SCC cases (100% negative). Stromal CD10 expression was positive in 50% of BCC cases and 75% of SCC cases. Stromal CD10 expression was significantly higher in high risk BCC and BCC with infiltrating deep margins; furthermore, it showed a significant positive correlation with grade of SCC. A significant inverse correlation between CD10 expression in stromal and tumor cells of BCC was present. Bcl2 was significantly expressed in 93.3% of SK cases and 80% of BCC cases when compared with SCC cases (100% negative). It was found that for distinguishing BCC from SK, only CD10 expression in tumor cells provided a high diagnostic value with positive likelihood ratio (PLR) was 7.00. In addition, CD10 and Bcl2 expression in tumor cells could give convincing diagnostic value to distinguish SCC from SK (PLR=15.00 for each marker). Moreover, for differentiating BCC from SCC, only Bcl2 in the tumor cells could provide a high diagnostic value (PLR=5.5). In conclusion, CD10 and Bcl2 can help in differentiating cutaneous BCC from SK and SCC. The overexpression of CD10 in the stromal cells of SCC and some variants of BCC suggests the invasive properties of such tumors. Copyright © 2015 Elsevier GmbH. All rights reserved.
Kowata, Kinue; Nakaoka, Minori; Nishio, Kaori; Fukao, Ayaka; Satoh, Akira; Ogoshi, Maho; Takahashi, Sumio; Tsudzuki, Masaoki; Takeuchi, Sakae
2014-05-25
Feathers are elaborate skin appendages shared by birds and theropod dinosaurs that have hierarchical branching of the rachis, barbs, and barbules. Feather filaments consist of β-keratins encoded by multiple genes, most of which are located in tandem arrays on chromosomes 2, 25, and 27 in chicken. The expansion of the genes is thought to have contributed to feather evolution; however, it is unclear how the individual genes are involved in feather formation. The aim of the present study was to identify feather keratin genes involved in the formation of barbules. Using a combination of microarray analysis, reverse-transcription polymerase chain reaction, and in situ hybridization, we found an uncharacterized keratin gene on chromosome 7 that was expressed specifically in barbule cells in regenerating chicken feathers. We have named the gene barbule specific keratin 1 (BlSK1). The BlSK1 gene structure was similar to the gene structure of previously characterized feather keratin genes, and consisted of a non-coding leader exon, an intron, and an exon with an open reading frame (ORF). The ORF was predicted to encode a 98 aa long protein, which shared 59% identity with feather keratin B. Orthologs of BlSK1 were found in the genomes of other avian species, including turkey, duck, zebra finch, and flycatcher, in regions that shared synteny with chromosome 7 of chicken. Interestingly, BlSK1 was expressed in feather follicles that generated pennaceous barbules but not in follicles that generated plumulaceous barbules. These results suggested that the composition of feather keratins probably varies depending on the structure of the feather filaments and, that individual feather keratin genes may be involved in building different portions and/or types of feathers in chicken. Copyright © 2014 Elsevier B.V. All rights reserved.
Estimates of (239+240)Pu inventories in Gdańsk Bay and Gdańsk basin.
Skwarzec, Bogdan; Strumińska, Dagmara I; Prucnal, Małgorzata
2003-01-01
This paper presents and discusses the results of (239+240)Pu determinations in different components of Gdańsk bay and Gdańsk basin ecosystem, as well as estimated sources and inventories of plutonium in these basins. The total plutonium (239+240)Pu activities deposited in Gdańsk bay and Gdańsk basin sediments are 1.18 TBq and 3.77 TBq, respectively. Two rivers, the Vistula and Neman rivers, and atmospheric fallout were distinguished as the main sources of plutonium in these basins. In seawater (with suspended matter included) there is about 2.33 GBq (239+240)Pu (0.2% of total activity) in Gdańsk bay and 9.92 GBq (239+240)Pu (0.3% of total activity) in Gdańsk basin. In both cases, 56% of (239+240)Pu is associated with suspended matter. Organisms contain 3.81 MBq in Gdańsk bay and 7.45 MBq (239+240)Pu in Gdańsk basin. From this value in Gdańsk bay 82.1% of plutonium is associated with zoobenthos, 13.6% with phytobenthos, 1.6% with phytoplankton, 1.5% with zooplankton and 1.2% with fish. In Gdańsk basin, 83.2% is associated with zoobenthos, 7.5% with phytobenthos, 3.6% with phytoplankton, 3.2% with zooplankton and 2.5% with fish.
Chusri, S; Sompetch, K; Mukdee, S; Jansrisewangwong, S; Srichai, T; Maneenoon, K; Limsuwan, S; Voravuthikunchai, S P
2012-01-01
Development of biofilm is a key mechanism involved in Staphylococcus epidermidis virulence during device-associated infections. We aimed to investigate antibiofilm formation and mature biofilm eradication ability of ethanol and water extracts of Thai traditional herbal recipes including THR-SK004, THR-SK010, and THR-SK011 against S. epidermidis. A biofilm forming reference strain, S. epidermidis ATCC 35984 was employed as a model for searching anti-biofilm agents by MTT reduction assay. The results revealed that the ethanol extract of THR-SK004 (THR-SK004E) could inhibit the formation of S. epidermidis biofilm on polystyrene surfaces. Furthermore, treatments with the extract efficiently inhibit the biofilm formation of the pathogen on glass surfaces determined by scanning electron microscopy and crystal violet staining. In addition, THR-SK010 ethanol extract (THR-SK010E; 0.63-5 μg/mL) could decrease 30 to 40% of the biofilm development. Almost 90% of a 7-day-old staphylococcal biofilm was destroyed after treatment with THR-SK004E (250 and 500 μg/mL) and THR-SK010E (10 and 20 μg/mL) for 24 h. Therefore, our results clearly demonstrated THR-SK004E could prevent the staphylococcal biofilm development, whereas both THR-SK004E and THR-SK010E possessed remarkable eradication ability on the mature staphylococcal biofilm.
ERIC Educational Resources Information Center
Clark, Donald M.
1992-01-01
Industry-education councils offer a systematic structure for implementing business-education partnerships, enabling vocational schools to link with the power structure of the employment community. Benefits include materials, equipment, inservice training and internships for teachers, job placement, and career information centers. (SK)
Leveraging Human Assets in Law Firms: Human Capital Structures and Organizational Capabilities.
ERIC Educational Resources Information Center
Sherer, Peter D.
1995-01-01
Using the ratio of associates to partners as a measure of human asset leveraging, analysis of data from 312 law firms reveals that the ratio is related to business strategy, human resource management practices, organizational structure, and the competitiveness of the firm. (SK)
Rai, Srijana; Nejadhamzeeigilani, Zaynab; Gutowski, Nicholas J; Whatmore, Jacqueline L
2015-09-25
Arrest of metastasising lung cancer cells to the brain microvasculature maybe mediated by interactions between ligands on circulating tumour cells and endothelial E-selectin adhesion molecules; a process likely to be regulated by the endothelial glycocalyx. Using human cerebral microvascular endothelial cells and non-small cell lung cancer (NSCLC) cell lines, we describe how factors secreted by NSCLC cells i.e. cystatin C, cathepsin L, insulin-like growth factor-binding protein 7 (IGFBP7), vascular endothelial growth factor (VEGF) and tumour necrosis factor-alpha (TNF-α), damage the glycocalyx and enhance initial contacts between lung tumour and cerebral endothelial cells. Endothelial cells were treated with tumour secreted-proteins or lung tumour conditioned medium (CM). Surface levels of E-selectin were quantified by ELISA. Adhesion of A549 and SK-MES-1 cells was examined under flow conditions (1 dyne/cm(2)). Alterations in the endothelial glycocalyx were quantified by binding of fluorescein isothiocyanate-linked wheat germ agglutinin (WGA-FITC). A549 and SK-MES-1 CM and secreted-proteins significantly enhanced endothelial surface E-selectin levels after 30 min and 4 h and tumour cell adhesion after 30 min, 4 and 24 h. Both coincided with significant glycocalyx degradation; A549 and SK-MES-1 CM removing 55 ± 12 % and 58 ± 18.7 % of WGA-FITC binding, respectively. Inhibition of E-selectin binding by monoclonal anti-E-selectin antibody completely attenuated tumour cell adhesion. These data suggest that metastasising lung cancer cells facilitate their own adhesion to the brain endothelium by secreting factors that damage the endothelial glycocalyx, resulting in exposure of the previously shielded adhesion molecules and engagement of the E-selectin-mediated adhesion axis.
ERIC Educational Resources Information Center
Litwin, Howard
1994-01-01
Responses from 93 of 100 Arab and Jewish social work students in Israel identified ethnicity as the primary factor in motivation for working with elderly people. Arab students had a significantly higher degree of motivation. A secondary factor was a venerating or modernist attitude toward the aged. (SK)
Hirasawa, Ai; Kaneko, Takahito; Tanaka, Naoki; Funane, Tsukasa; Kiguchi, Masashi; Sørensen, Henrik; Secher, Niels H; Ogoh, Shigehiko
2016-04-01
We estimated cerebral oxygenation during handgrip exercise and a cognitive task using an algorithm that eliminates the influence of skin blood flow (SkBF) on the near-infrared spectroscopy (NIRS) signal. The algorithm involves a subtraction method to develop a correction factor for each subject. For twelve male volunteers (age 21 ± 1 yrs) +80 mmHg pressure was applied over the left temporal artery for 30 s by a custom-made headband cuff to calculate an individual correction factor. From the NIRS-determined ipsilateral cerebral oxyhemoglobin concentration (O2Hb) at two source-detector distances (15 and 30 mm) with the algorithm using the individual correction factor, we expressed cerebral oxygenation without influence from scalp and scull blood flow. Validity of the estimated cerebral oxygenation was verified during cerebral neural activation (handgrip exercise and cognitive task). With the use of both source-detector distances, handgrip exercise and a cognitive task increased O2Hb (P < 0.01) but O2Hb was reduced when SkBF became eliminated by pressure on the temporal artery for 5 s. However, when the estimation of cerebral oxygenation was based on the algorithm developed when pressure was applied to the temporal artery, estimated O2Hb was not affected by elimination of SkBF during handgrip exercise (P = 0.666) or the cognitive task (P = 0.105). These findings suggest that the algorithm with the individual correction factor allows for evaluation of changes in an accurate cerebral oxygenation without influence of extracranial blood flow by NIRS applied to the forehead.
Ku-Yuan, Lee; Li-Chi, Lan; Jiun-Hao, Wang; Chen-Ling, Fang; Kun-Sun, Shiao
2014-06-04
To control the latent social risk of disease, the government usually spreads accurate information and attempts to improve the public's attitude toward adopting prevention. However, these methods with the Knowledge, Attitudes, and Practices (KAP) model do not always work. Therefore, we used the theory of planned behavior (TPB) to understand dog owners' behavior and distinguished the knowledge effect as objective knowledge (OK) and subjective knowledge (SK). A total of 310 dog owners completed a questionnaire based on our model. We employed structural equation modeling to verify the structural relationships and found three main results. First, our model was fit, and each path was significant. People with better attitudes, stronger subjective norms, and more perceptive behavioral control have stronger behavioral intention. Second, perceived behavioral control, not attitude, was the best predictive index in this model. Finally, on perceived behavioral control, subjective knowledge showed more influence than objective knowledge. We successfully extended TPB to explain the behavioral intention of dog owners and presented more workable recommendations. To reduce the latent social risk of disease, the government should not only address dog owners' attitudes, but also their subjective norms and perceptive behavioral control. Indeed, perceptive behavioral control and SK showed the most influence in this model. It is implied that the self-efficacy of dog owners is the most important factor in such a behavior. Therefore, the government should focus on enhancing dog owners' self-efficacy first while devoted to prevention activities.
Ku-Yuan, Lee; Li-Chi, Lan; Jiun-Hao, Wang; Chen-Ling, Fang; Kun-Sun, Shiao
2014-01-01
To control the latent social risk of disease, the government usually spreads accurate information and attempts to improve the public’s attitude toward adopting prevention. However, these methods with the Knowledge, Attitudes, and Practices (KAP) model do not always work. Therefore, we used the theory of planned behavior (TPB) to understand dog owners’ behavior and distinguished the knowledge effect as objective knowledge (OK) and subjective knowledge (SK). A total of 310 dog owners completed a questionnaire based on our model. We employed structural equation modeling to verify the structural relationships and found three main results. First, our model was fit, and each path was significant. People with better attitudes, stronger subjective norms, and more perceptive behavioral control have stronger behavioral intention. Second, perceived behavioral control, not attitude, was the best predictive index in this model. Finally, on perceived behavioral control, subjective knowledge showed more influence than objective knowledge. We successfully extended TPB to explain the behavioral intention of dog owners and presented more workable recommendations. To reduce the latent social risk of disease, the government should not only address dog owners’ attitudes, but also their subjective norms and perceptive behavioral control. Indeed, perceptive behavioral control and SK showed the most influence in this model. It is implied that the self-efficacy of dog owners is the most important factor in such a behavior. Therefore, the government should focus on enhancing dog owners’ self-efficacy first while devoted to prevention activities. PMID:24901413
Materials Degradation & Failure: Assessment of Structure and Properties. Resources in Technology.
ERIC Educational Resources Information Center
Technology Teacher, 1991
1991-01-01
This module provides information on materials destruction (through corrosion, oxidation, and degradation) and failure. A design brief includes objective, student challenge, resources, student outcomes, and quiz. (SK)
Developmental profile of SK2 channel expression and function in CA1 neurons
Ballesteros-Merino, Carmen; Lin, Mike; Wu, Wendy W.; Ferrandiz-Huertas, Clotilde; Cabañero, María J.; Watanabe, Masahiko; Fukazawa, Yugo; Shigemoto, Ryuichi; Maylie, James; Adelman, John P.; Luján, Rafael
2012-01-01
We investigated the temporal and spatial expression of SK2 in the developing mouse hippocampus using molecular and biochemical techniques, quantitative immunogold electron microscopy and electrophysiology. The mRNA encoding SK2 was expressed in the developing and adult hippocampus. Western blotting and immunohistochemistry showed that SK2 protein increased with age. This was accompanied by a shift in subcellular localization. Early in development (P5), SK2 was predominantly localized to the endoplasmic reticulum in the pyramidal cell layer. But by P30 SK2 was almost exclusively expressed in the dendrites and spines. The level of SK2 at the postsynaptic density (PSD) also increased during development. In the adult, SK2 expression on the spine plasma membrane showed a proximal-to-distal gradient. Consistent with this redistribution and gradient of SK2, the selective SK channel blocker apamin increased evoked excitatory postsynaptic potentials (EPSPs) only in CA1 pyramidal neurons from mice older than P15. However, the effect of apamin on EPSPs was not different between synapses in proximal or distal stratum radiatum or stratum lacunosum-moleculare in adult. These results show a developmental increase and gradient in SK2-containing channel surface expression that underlie their influence on neurotransmission, and that may contribute to increased memory acquisition during early development. PMID:22072564
ERIC Educational Resources Information Center
Hopkins, Charles O.
1982-01-01
Outlines key indicators of the current economic recession and discusses these factors as they will affect the American Vocational Association. Asserts that vocational education has an integral role in economic recovery and growth. (SK)
Physical Therapy Continuing Education. Part II: Motivating Factors.
ERIC Educational Resources Information Center
Karp, Nancy V.
1992-01-01
A survey of Georgia physical therapists received responses from 74.7 percent. Results identified the following motivations for continuing education: knowledge, meeting licensure requirements, and advancing in the present job. (SK)
Ježek, Jan; Engstová, Hana; Ježek, Petr
2017-09-01
Previously suggested antioxidant mechanisms for mitochondria-targeted plastoquinone SkQ1 included: i) ion-pairing of cationic SkQ1 + with free fatty acid anions resulting in uncoupling; ii) SkQ1H 2 ability to interact with lipoperoxyl radical; iii) interference with electron flow at the inner ubiquinone (Q) binding site of Complex III (Q i ), involving the reduction of SkQ1 to SkQ1H 2 by ubiquinol. We elucidated SkQ1 antioxidant properties by confocal fluorescence semi-quantification of mitochondrial superoxide (J m ) and cytosolic H 2 O 2 (J c ) release rates in HepG2 cells. Only in glycolytic cells, SkQ1 prevented the rotenone-induced enhancement of J m and J c but not basal releases without rotenone. The effect ceased in glutaminolytic aglycemic cells, in which the redox parameter NAD(P)H/FAD increased after rotenone in contrast to its decrease in glycolytic cells. Autofluorescence decay indicated decreased NADPH/NADH ratios with rotenone in both metabolic modes. SkQ1 did not increase cell respiration and diminished J m established high by antimycin or myxothiazol but not by stigmatellin. The revealed SkQ1 antioxidant modes reflect its reduction to SkQ1H 2 at Complex I I Q or Complex III Q i site. Both reductions diminish electron diversions to oxygen thus attenuating superoxide formation. Resulting SkQ1H 2 oxidizes back to SkQ1at the second (flavin) Complex I site, previously indicated for MitoQ 10 . Regeneration proceeds only at lower NAD(P)H/FAD in glycolytic cells. In contrast, cyclic SkQ1 reduction/SkQ1H 2 oxidation does not substantiate antioxidant activity in intact cells in the absence of oxidative stress (neither pro-oxidant activity, representing a great advantage). A targeted delivery to oxidative-stressed tissues is suggested for the effective antioxidant therapy based on SkQ1. Copyright © 2017 Elsevier B.V. All rights reserved.
The relationship between solar keratoses and squamous cell carcinomas among Japanese.
Takemiya, M; Ohtsuka, H; Miki, Y
1990-06-01
Between 1976 and 1988, 135 patients with solar keratosis (SK) and 53 patients with squamous cell carcinoma (SCC) on the sun-exposed skin, but without apparent preceding diseases such as burn scars, chronic radiodermatitis, chronic arsenic poisoning, or xeroderma pigmentosum, were encountered. Sixteen of the SCC patients also had SK on other areas of sun-exposed skin. There were 31 SCC patients also showing SK (SK-SCC) and 22 SCC not showing SK (DN-SCC) within the same histologic sections. The mean ages of the patients with SK-SCC and with DN-SCC were similar. Metastases to regional lymph nodes were observed in 5 SK-SCC patients, of whom 3 died of the disease, and in 5 DN-SCC patients, of whom 4 died of the disease. The five-year post-operative survival rates were 70% in SK-SCC and 74% in DN-SCC; the ten-year post-operative survival rates were 70% in SK-SCC and 44% in DN-SCC.
Novel ion channel targets in atrial fibrillation.
Hancox, Jules C; James, Andrew F; Marrion, Neil V; Zhang, Henggui; Thomas, Dierk
2016-08-01
Atrial fibrillation (AF) is the most common arrhythmia in humans. It is progressive and the development of electrical and structural remodeling makes early intervention desirable. Existing antiarrhythmic pharmacological approaches are not always effective and can produce unwanted side effects. Additional atrial-selective antiarrhythmic strategies are therefore desirable. Evidence for three novel ion channel atrial-selective therapeutic targets is evaluated: atrial-selective fast sodium channel current (INa) inhibition; small conductance calcium-activated potassium (SK) channels; and two-pore (K2P) potassium channels. Data from animal models support atrial-ventricular differences in INa kinetics and also suggest atrial-ventricular differences in sodium channel β subunit expression. Further work is required to determine whether intrinsic atrial-ventricular differences in human INa exist or whether functional differences occur due to distinct atrial and ventricular action and resting potentials. SK and K2P channels (particularly K2P 3.1) offer potentially attractive atrial-selective targets. Work is needed to identify the underlying basis of SK current that contributes to (patho)physiological atrial repolarization and settings in which SK inhibition is anti- versus pro-arrhythmic. Although K2P3.1 appears to be a promising target with comparatively selective drugs for experimental use, a lack of selective pharmacology hinders evaluation of other K2P channels as potential atrial-selective targets.
Recchia, Anna Grazia; De Francesco, Ernestina Marianna; Vivacqua, Adele; Sisci, Diego; Panno, Maria Luisa; Andò, Sebastiano; Maggiolini, Marcello
2011-03-25
GPR30, also known as GPER, has been suggested to mediate rapid effects induced by estrogens in diverse normal and cancer tissues. Hypoxia is a common feature of solid tumors involved in apoptosis, cell survival, and proliferation. The response to low oxygen environment is mainly mediated by the hypoxia-inducible factor named HIF-1α, which activates signaling pathways leading to adaptive mechanisms in tumor cells. Here, we demonstrate that the hypoxia induces HIF-1α expression, which in turn mediates the up-regulation of GPER and its downstream target CTGF in estrogen receptor-negative SkBr3 breast cancer cells and in HL-1 cardiomyocytes. Moreover, we show that HIF-1α-responsive elements located within the promoter region of GPER are involved in hypoxia-dependent transcription of GPER, which requires the ROS-induced activation of EGFR/ERK signaling in both SkBr3 and HL-1 and cells. Interestingly, the apoptotic response to hypoxia was prevented by estrogens through GPER in SkBr3 cells. Taken together, our data suggest that the hypoxia-induced expression of GPER may be included among the mechanisms involved in the anti-apoptotic effects elicited by estrogens, particularly in a low oxygen microenvironment.
Taub, Pam R; Ramirez-Sanchez, Israel; Patel, Minal; Higginbotham, Erin; Moreno-Ulloa, Aldo; Román-Pintos, Luis Miguel; Phillips, Paul; Perkins, Guy; Ceballos, Guillermo; Villarreal, Francisco
2016-09-14
In heart failure patients the consumption of (-)-epicatechin ((-)-Epi)-rich cocoa can restore skeletal muscle (SkM) mitochondrial structure and decrease biomarkers of oxidative stress. However, nothing is known about its effects on exercise capacity and underlying mechanisms in normal, sedentary subjects. Twenty normal, sedentary subjects (∼50 years old) were randomized to placebo or dark chocolate (DC) groups and consumed 20 g of the products for 3 months. Subjects underwent before and after treatment, bicycle ergometry to assess VO2 max and work, SkM biopsy to assess changes in mitochondrial density, function and oxidative stress and blood sampling to assess metabolic endpoints. Seventeen subjects completed the trial. In the DC group (n = 9), VO2 max increased (17% increase, p = 0.056) as well as maximum work (watts) achieved (p = 0.026) with no changes with placebo (n = 8). The DC group evidenced increases in HDL levels (p = 0.005) and decreased triglycerides (p = 0.07). With DC, SkM evidenced significant increases in protein levels for LKB1, AMPK and PGC1α and in their active forms (phosphorylated AMPK and LKB1) as well as in citrate synthase activity while no changes were observed in mitochondrial density. With DC, significant increases in SkM reduced glutathione levels and decreases in protein carbonylation were observed. Improvements in maximum work achieved and VO2 max may be due to DC activation of upstream control systems and enhancement of SkM mitochondria efficiency. Larger clinical studies are warranted to confirm these observations.
Taub, Pam R.; Ramirez-Sanchez, Israel; Patel, Minal; Higginbotham, Erin; Moreno-Ulloa, Aldo; Román-Pintos, Luis Miguel; Phillips, Paul; Perkins, Guy; Ceballos, Guillermo; Villarreal, Francisco
2016-01-01
In heart failure patients the consumption of (-)-epicatechin ((-)-Epi)-rich cocoa can restore skeletal muscle (SkM) mitochondrial structure and decrease biomarkers of oxidative stress. However, nothing is known about its effects on exercise capacity and underlying mechanisms in normal, sedentary subjects. Twenty normal, sedentary subjects (∼50 years old) were randomized to placebo or dark chocolate (DC) groups and consumed 20 g of the products for 3 months. Subjects underwent before and after treatment, bicycle ergometry to assess VO2 max and work, SkM biopsy to assess changes in mitochondrial density, function and oxidative stress and blood sampling to assess metabolic endpoints. Seventeen subjects completed the trial. In the DC group (n=9), VO2 max increased (17% increase, p=0.056) as well as maximum work (watts) achieved (p=0.026) with no changes with placebo (n=8). The DC group evidenced increases in HDL levels (p=0.005) and decreased triglycerides (p=0.07). With DC, SkM evidenced significant increases in protein levels for LKB1, AMPK and PGC1α and in their active forms (phosphorylated AMPK and LKB1) as well as in citrate synthase activity while no changes were observed in mitochondrial density. With DC, significant increases in SkM reduced glutathione levels and decreases in protein carbonylation were observed. Improvements in maximum work achieved and VO2 max may be due to DC activation of upstream control systems and enhancement of SkM mitochondria efficiency. Larger clinical studies are warranted to confirm these observations. PMID:27491778
EOVSA Implementation of a Spectral Kurtosis Correlator for Transient Detection and Classification
NASA Astrophysics Data System (ADS)
Nita, Gelu M.; Hickish, Jack; MacMahon, David; Gary, Dale E.
2016-03-01
We describe in general terms the practical use in astronomy of a higher-order statistical quantity called spectral kurtosis (SK), and describe the first implementation of SK-enabled firmware in the Fourier transform-engine (F-engine) of a digital FX correlator for the Expanded Owens Valley Solar Array (EOVSA). The development of the theory for SK is summarized, leading to an expression for generalized SK that is applicable to both SK spectrometers and those not specifically designed for SK. We also give the means for computing both the SK̂ estimator and thresholds for its application as a discriminator of RFI contamination. Tests of the performance of EOVSA as an SK spectrometer are shown to agree precisely with theoretical expectations, and the methods for configuring the correlator for correct SK operation are described.
Chusri, S.; Sompetch, K.; Mukdee, S.; Jansrisewangwong, S.; Srichai, T.; Maneenoon, K.; Limsuwan, S.; Voravuthikunchai, S. P.
2012-01-01
Development of biofilm is a key mechanism involved in Staphylococcus epidermidis virulence during device-associated infections. We aimed to investigate antibiofilm formation and mature biofilm eradication ability of ethanol and water extracts of Thai traditional herbal recipes including THR-SK004, THR-SK010, and THR-SK011 against S. epidermidis. A biofilm forming reference strain, S. epidermidis ATCC 35984 was employed as a model for searching anti-biofilm agents by MTT reduction assay. The results revealed that the ethanol extract of THR-SK004 (THR-SK004E) could inhibit the formation of S. epidermidis biofilm on polystyrene surfaces. Furthermore, treatments with the extract efficiently inhibit the biofilm formation of the pathogen on glass surfaces determined by scanning electron microscopy and crystal violet staining. In addition, THR-SK010 ethanol extract (THR-SK010E; 0.63–5 μg/mL) could decrease 30 to 40% of the biofilm development. Almost 90% of a 7-day-old staphylococcal biofilm was destroyed after treatment with THR-SK004E (250 and 500 μg/mL) and THR-SK010E (10 and 20 μg/mL) for 24 h. Therefore, our results clearly demonstrated THR-SK004E could prevent the staphylococcal biofilm development, whereas both THR-SK004E and THR-SK010E possessed remarkable eradication ability on the mature staphylococcal biofilm. PMID:22919409
Imbs, Tatiana I; Ermakova, Svetlana P; Malyarenko Vishchuk, Olesya S; Isakov, Vladimir V; Zvyagintseva, Tatiana N
2016-01-01
Laminaran, fucoidan, and alginate were isolated from the brown alga Coccophora langsdorfii collected in the Japan Sea. The structural characteristics of polysaccharides were investigated by NMR spectroscopy. The laminaran was determined as β-d-glucan, which consisted of 80% of 1,3- and 20% of 1,6-linked residues and was terminated with mannitol. The alginate was a guluronic acid-rich polysaccharide (M/G=0.85). Fucoidan, sulfated α-l-fucan, contained a linear backbone of alternating (1→3)- and (1→4)- linked α-l-fucopyranose residues with sulfate at C2 and C4 of (1→3)-α-l-fucopyranose residues. Anticancer activity of this fucoidan was investigated in comparison with activity of fucoidan having similar linear backbone from the brown alga Fucus evanescens. The fucoidan from C. langsdorfii significantly inhibited colony formation of SK-MEL-5 and SK-MEL-28 melanoma cells (the percentage of inhibition was 28 and 76, respectively) and weakly inhibited colony formation of breast adenocarcinoma cells MDA-MB-231 (the percentage of inhibition was about 5). Similar results were obtained for fucoidan from F. evanescens; the percentage of inhibition of colony formation of SK-MEL-5 and SK-MEL-28 melanoma cells was 54 and 56, respectively. The inhibition of colony formation of breast adenocarcinoma cells MDA-MB-231 was weak. We suppose that other sulfated and partially acetylated fucoidans consisting of (1→3)- and (1→4)-linked α-l-fucopyranose residues may suppress progression of melanoma cell colony formation similar to fucoidans of C. langsdorfii and F. evanescens. Copyright © 2015 Elsevier Ltd. All rights reserved.
Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation.
Gaviglio, Angela L; Knelson, Erik H; Blobe, Gerard C
2017-05-01
High-risk neuroblastoma is characterized by undifferentiated neuroblasts and low schwannian stroma content. The tumor stroma contributes to the suppression of tumor growth by releasing soluble factors that promote neuroblast differentiation. Here we identify heparin-binding epidermal growth factor-like growth factor (HBEGF) as a potent prodifferentiating factor in neuroblastoma. HBEGF mRNA expression is decreased in human neuroblastoma tumors compared with benign tumors, with loss correlating with decreased survival. HBEGF protein is expressed only in stromal compartments of human neuroblastoma specimens, with tissue from high-stage disease containing very little stroma or HBEGF expression. In 3 human neuroblastoma cell lines (SK-N-AS, SK-N-BE2, and SH-SY5Y), soluble HBEGF is sufficient to promote neuroblast differentiation and decrease proliferation. Heparan sulfate proteoglycans and heparin derivatives further enhance HBEGF-induced differentiation by forming a complex with the epidermal growth factor receptor, leading to activation of the ERK1/2 and STAT3 pathways and up-regulation of the inhibitor of DNA binding transcription factor. These data support a role for loss of HBEGF in the neuroblastoma tumor microenvironment in neuroblastoma pathogenesis.-Gaviglio, A. L., Knelson, E. H., Blobe, G. C. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation. © FASEB.
The Business Policy Course: Multiple Methods for Multiple Goals.
ERIC Educational Resources Information Center
Thomas, Anisya S.
1998-01-01
Outlines the objectives of a capstone business policy and strategy course; the use of case analysis, article critiques, storytelling, and computer simulation; and contextual factors in matching objectives and methods. (SK)
The Brain, Learning, and Technology.
ERIC Educational Resources Information Center
Deters, Thomas J.
1999-01-01
New research findings on memory and learning systems have implications for continuing medical education in terms of format and length of learning activities, age of learners, and psychological factors such as stress and mental fatigue. (SK)
NASA Astrophysics Data System (ADS)
Ito, S.; Takaku, Y.; Ikeda, M.; Kishimoto, Y.
2017-11-01
The new Super-Kamiokande-Gadolinium (SK-Gd) project is an upgrade of the Super-Kamiokande (SK) detector. In the SK-Gd project, 0.2% Gd_2(SO_4)_3 is loaded into the 50 kton water tank of the SK. One of the main purposes of the project is to discover supernova relic neutrinos. Neutrino measurements and proton decay searches will also be performed in the SK-Gd. In order to measure solar neutrinos with a low energy threshold of ˜3.5 MeV in the SK-Gd, the main radioactive contaminations, ^{238}U and ^{232}Th, in Gd_2(SO_4)_3{\\cdot}8H_2O, should be minimized before loading. Our maximum levels for U and Th are 5 mBq (U)/kg (Gd_2(SO_4)_3{\\cdot}8H_2O) and 0.05 mBq (Th)/kg (Gd_2(SO_4)_3{\\cdot}8H_2O). In order to measure such low concentrations of U and Th in Gd_2(SO_4)_3{\\cdot}8H_2O, we developed the solid-phase extraction technique. Using this method, about 90% or more U and Th could be efficiently extracted while Gd was reduced by a factor of about 104. This allowed these radioactivity contaminations to be measured precisely as 0.04 mBq/kg (Gd_2(SO_4)_3{\\cdot}8H_2O) for U and 0.01 mBq/kg (Gd_2(SO_4)_3{\\cdot}8H_2O) for Th. We measured three pure Gd_2(SO_4)_3{\\cdot}8H_2O samples using this method and estimated that the purest one contained <0.04 mBq (U)/kg (Gd_2(SO_4)_3{\\cdot}8H_2O) and 0.06 ± 0.01 mBq (Th)/kg (Gd_2(SO_4)_3{\\cdot}8H_2O) by the ICP-MS.
Purification and Characterization of Schwann Cells from Adult Human Skin and Nerve
Stratton, Jo Anne; Shah, Prajay; Shapira, Yuval; Midha, Rajiv
2017-01-01
Abstract Despite its modest capacity for regeneration, peripheral nervous system injury often results in significant long-term disability. Supplementing peripheral nervous system injury with autologous Schwann cells (SCs) may serve to rejuvenate the postinjury environment to enhance regeneration and ultimately improve functional outcomes. However, human nerve-derived SC (hN-SC) collection procedures require invasive surgical resection. Here, we describe the characterization of SCs from adult human skin (hSk-SCs) of four male donors ranging between 27 and 46 years old. Within five weeks of isolating and culturing adherent mixed skin cells, we were able to obtain 3–5 million purified SCs. We found that hSk-SCs appeared transcriptionally indistinguishable from hN-SCs with both populations exhibiting expression of SC genes including: SOX10, SOX9, AP2A1, CDH19, EGR1, ETV5, PAX3, SOX2, CX32, DHH, NECL4, NFATC4, POU3F1, S100B, and YY1. Phenotypic analysis of hSk-SCs and hN-SCs cultures revealed highly enriched populations of SCs indicated by the high percentage of NES+ve, SOX10+ve, s100+ve and p75+ve cells, as well as the expression of a battery of other SC-associated proteins (PAX3, CDH19, ETV5, SOX2, POU3F1, S100B, EGR2, and YY1). We further show that both hSk-SCs and hN-SCs are capable of promoting axonal growth to similar degrees and that a subset of both associate with regenerating axons and form myelin following transplantation into the injured mouse sciatic nerve. Interestingly, although the majority of both hSk-SCs and hN-SCs maintained SOX10 immunoreactivity following transplant, only a subset of each activated the promyelinating factor, POU3F1, and were able to myelinate. Taken together, we demonstrate that adult hSk-SCs are genetically and phenotypically indistinguishable to hN-SCs. PMID:28512649
Low energy neutrinos in Super-Kamiokande
NASA Astrophysics Data System (ADS)
Sekiya, Hiroyuki
2016-05-01
Super-Kamiokande (SK), a 50 kton water Cherenkov detector, observes 8B solar neutrinos via neutrino-electron elastic scattering. The analysis threshold was successfully lowered to 3.5 MeV (recoil electron kinetic energy) in SK-IV. To date SK has observed solar neutrinos for 18 years. An analysis regarding possible correlations between the solar neutrino flux and the 11 year solar activity cycle is shown. With large statistics, SK searches for distortions of the solar neutrino energy spectrum caused by the MSW resonance in the core of the sun. SK also searches for a day/night solar neutrino flux asymmetry induced by the matter in the Earth. The Super-Kamiokande Gd (SK-Gd) project is the upgrade of the SK detector via the addition of water-soluble gadolinium (Gd) salt. This modification will enable it to efficiently identify low energy anti-neutrinos. SK-Gd will pursue low energy physics currently inaccessible to SK due to backgrounds. The most important will be the world’s first observation of the diffuse supernova neutrino background. The main R&D program towards SK-Gd is EG ADS: a 200 ton, fully instrumented tank built in a new cavern in the Kamioka mine.
The CCK(-like) receptor in the animal kingdom: functions, evolution and structures.
Staljanssens, Dorien; Azari, Elnaz Karimian; Christiaens, Olivier; Beaufays, Jérôme; Lins, Laurence; Van Camp, John; Smagghe, Guy
2011-03-01
In this review, the cholecystokinin (CCK)(-like) receptors throughout the animal kingdom are compared on the level of physiological functions, evolutionary basis and molecular structure. In vertebrates, the CCK receptor is an important member of the G-protein coupled receptors as it is involved in the regulation of many physiological functions like satiety, gastrointestinal motility, gastric acid secretion, gall bladder contraction, pancreatic secretion, panic, anxiety and memory and learning processes. A homolog for this receptor is also found in nematodes and arthropods, called CK receptor and sulfakinin (SK) receptor, respectively. These receptors seem to have evolved from a common ancestor which is probably still closely related to the nematode CK receptor. The SK receptor is more closely related to the CCK receptor and seems to have similar functions. A molecular 3D-model for the CCK receptor type 1 has been built together with the docking of the natural ligands for the CCK and SK receptors in the CCK receptor type 1. These molecular models can help to study ligand-receptor interactions, that can in turn be useful in the development of new CCK(-like) receptor agonists and antagonists with beneficial health effects in humans or potential for pest control. Copyright © 2010 Elsevier Inc. All rights reserved.
Parajuli, Shankar P; Hristov, Kiril L; Soder, Rupal P; Kellett, Whitney F; Petkov, Georgi V
2013-01-01
Background and Purpose Overactive bladder (OAB) is often associated with abnormally increased detrusor smooth muscle (DSM) contractions. We used NS309, a selective and potent opener of the small or intermediate conductance Ca2+-activated K+ (SK or IK, respectively) channels, to evaluate how SK/IK channel activation modulates DSM function. Experimental Approach We employed single-cell RT-PCR, immunocytochemistry, whole cell patch-clamp in freshly isolated rat DSM cells and isometric tension recordings of isolated DSM strips to explore how the pharmacological activation of SK/IK channels with NS309 modulates DSM function. Key Results We detected SK3 but not SK1, SK2 or IK channels expression at both mRNA and protein levels by RT-PCR and immunocytochemistry in DSM single cells. NS309 (10 μM) significantly increased the whole cell SK currents and hyperpolarized DSM cell resting membrane potential. The NS309 hyperpolarizing effect was blocked by apamin, a selective SK channel inhibitor. NS309 inhibited the spontaneous phasic contraction amplitude, force, frequency, duration and tone of isolated DSM strips in a concentration-dependent manner. The inhibitory effect of NS309 on spontaneous phasic contractions was blocked by apamin but not by TRAM-34, indicating no functional role of the IK channels in rat DSM. NS309 also significantly inhibited the pharmacologically and electrical field stimulation-induced DSM contractions. Conclusions and Implications Our data reveal that SK3 channel is the main SK/IK subtype in rat DSM. Pharmacological activation of SK3 channels with NS309 decreases rat DSM cell excitability and contractility, suggesting that SK3 channels might be potential therapeutic targets to control OAB associated with detrusor overactivity. PMID:23145946
Scherer, Elias Q; Yang, Jingli; Canis, Martin; Reimann, Katrin; Ivanov, Karolina; Diehl, Christian D; Backx, Peter H; Wier, W Gil; Strieth, Sebastian; Wangemann, Philine; Voigtlaender-Bolz, Julia; Lidington, Darcy; Bolz, Steffen-Sebastian
2010-11-01
We sought to demonstrate that tumor necrosis factor (TNF)-α, via sphingosine-1-phosphate signaling, has the potential to alter cochlear blood flow and thus, cause ischemic hearing loss. We performed intravital fluorescence microscopy to measure blood flow and capillary diameter in anesthetized guinea pigs. To measure capillary diameter ex vivo, capillary beds from the gerbil spiral ligament were isolated from the cochlear lateral wall and maintained in an organ bath. Isolated gerbil spiral modiolar arteries, maintained and transfected in organ culture, were used to measure calcium sensitivity (calcium-tone relationship). In a clinical study, a total of 12 adult patients presenting with typical symptoms of sudden hearing loss who were not responsive or only partially responsive to prednisolone treatment were identified and selected for etanercept treatment. Etanercept (25 mg s.c.) was self-administered twice a week for 12 weeks. TNF-α induced a proconstrictive state throughout the cochlear microvasculature, which reduced capillary diameter and cochlear blood flow in vivo. In vitro isolated preparations of the spiral modiolar artery and spiral ligament capillaries confirmed these observations. Antagonizing sphingosine-1-phosphate receptor 2 subtype signaling (by 1 μmol/L JTE013) attenuated the effects of TNF-α in all models. TNF-α activated sphingosine kinase 1 (Sk1) and induced its translocation to the smooth muscle cell membrane. Expression of a dominant-negative Sk1 mutant (Sk1(G82D)) eliminated both baseline spiral modiolar artery calcium sensitivity and TNF-α effects, whereas a nonphosphorylatable Sk1 mutant (Sk1(S225A)) blocked the effects of TNF-α only. A small group of etanercept-treated, hearing loss patients recovered according to a 1-phase exponential decay (half-life=1.56 ± 0.20 weeks), which matched the kinetics predicted for a vascular origin. TNF-α indeed reduces cochlear blood flow via activation of vascular sphingosine-1-phosphate signaling. This integrates hearing loss into the family of ischemic microvascular pathologies, with implications for risk stratification, diagnosis, and treatment.
Quantum Chemistry via the Periodic Law.
ERIC Educational Resources Information Center
Blinder, S. M.
1981-01-01
Describes an approach to quantum mechanics exploiting the periodic structure of the elements as a foundation for the quantum theory of matter. Indicates that a quantum chemistry course can be developed using this approach. (SK)
Chemical Process Design: An Integrated Teaching Approach.
ERIC Educational Resources Information Center
Debelak, Kenneth A.; Roth, John A.
1982-01-01
Reviews a one-semester senior plant design/laboratory course, focusing on course structure, student projects, laboratory assignments, and course evaluation. Includes discussion of laboratory exercises related to process waste water and sludge. (SK)
Employee Participation--A Practical Guide.
ERIC Educational Resources Information Center
Wooden, Mark
1990-01-01
Despite the benefits of employee participation in decision making, it is not widespread. Making it work requires commitment, job security, training, access to information, communication channels, goal setting, flat organizational structures, and financial reinforcement. (SK)
Educating for Peace: The Australian Experience.
ERIC Educational Resources Information Center
Swee-Hin, Toh; Burns, Robin
1989-01-01
The many facets of the peace education movement in Australia include (1) development education, which focuses on inequities in the global economic structure; (2) demilitarization and disarmament; and (3) conservation of the environment. (SK)
da Cunha, André L; Aguiar, Jair A K; Correa da Silva, Flavio S; Michelacci, Yara M
2017-10-01
The aim of the present study was to investigate the activities of natural chondroitin sulfates (CS) with different structures on cultured chondrocytes and macrophages. CS were isolated from cartilages of bovine trachea (BT), porcine trachea (PT), chicken sternum (Ch) and skate (Sk). The preparations were 90-98% pure, with ∼1% proteins, nucleic acids and keratan sulfate contaminants. Structural analysis of these CS and of commercial chondroitin 4- and 6-sulfate (C4S, C6S) have shown that most of their disaccharides are monosulfated, with varying proportions of 4- and 6-sulfation, and 2-7% non-sulfated disaccharides. Sk-CS and C6S contained detectable amounts of disulfated disaccharides. All the CS were polydisperse, with modal molecular weights of 26-135kDa. These CS had anti-inflammatory activities on both chondrocytes and macrophages, but with different efficiencies. On horse and human chondrocytes, they reduced the IL-1β-induced liberation of NO and PGE 2 , and on RAW 264.7 immortalized macrophage-like cell line, C4S, C6S, Ch and Sk-CS decreased the LPS-induced liberation of TNF-α, but did not affect IL-6. In contrast, on bone marrow derived macrophages, C4S, C6S, BT and PT-CS reduced the LPS-induced liberation of TNF-α, IL-6, IL-1β and NO, indicating that the RAW response to CS was different from that of primary macrophages. Copyright © 2017 Elsevier B.V. All rights reserved.
Noble, Karen; Floyd, Rachel; Shmygol, Andre; Shmygol, Anatoly; Mobasheri, A; Wray, Susan
2010-01-01
Calcium-activated potassium channels are important in a variety of smooth muscles, contributing to excitability and contractility. In the myometrium previous work has focussed on the large conductance channels (BK), and the role of small conductance channels (SK) has received scant attention, despite the finding that over-expression of an SK channel isoform (SK3) results in uterine dysfunction and delayed parturition. This study therefore characterises the expression of the three SK channel isoforms (SK1-3) in rat myometrium throughout pregnancy and investigates their effect on cytosolic [Ca] and force and compares this with that of BK channels. Consistent expression of all SK isoform transcripts and clear immunostaining of SK1-3 was found. Inhibition of SK1-3 channels (apamin, scyllatoxin) significantly inhibited outward current, caused membrane depolarisation and elicited action potentials in previously quiescent cells. Apamin or scyllatoxin increased the amplitude of [Ca] and force in spontaneously contracting myometrial strips throughout gestation. The functional effect of SK inhibition was larger than that of BK channel inhibition. Thus we show for the first time that SK1-3 channels are expressed and translated throughout pregnancy and contribute to outward current, regulate membrane potential and hence Ca signals in pregnant rat myometrium. They contribute more to quiescence that BK channels. 2009 Elsevier Ltd. All rights reserved.
Coupling of SK channels, L-type Ca2+ channels, and ryanodine receptors in cardiomyocytes.
Zhang, Xiao-Dong; Coulibaly, Zana A; Chen, Wei Chun; Ledford, Hannah A; Lee, Jeong Han; Sirish, Padmini; Dai, Gu; Jian, Zhong; Chuang, Frank; Brust-Mascher, Ingrid; Yamoah, Ebenezer N; Chen-Izu, Ye; Izu, Leighton T; Chiamvimonvat, Nipavan
2018-03-16
Small-conductance Ca 2+ -activated K + (SK) channels regulate the excitability of cardiomyocytes by integrating intracellular Ca 2+ and membrane potentials on a beat-to-beat basis. The inextricable interplay between activation of SK channels and Ca 2+ dynamics suggests the pathology of one begets another. Yet, the exact mechanistic underpinning for the activation of cardiac SK channels remains unaddressed. Here, we investigated the intracellular Ca 2+ microdomains necessary for SK channel activation. SK currents coupled with Ca 2+ influx via L-type Ca 2+ channels (LTCCs) continued to be elicited after application of caffeine, ryanodine or thapsigargin to deplete SR Ca 2+ store, suggesting that LTCCs provide the immediate Ca 2+ microdomain for the activation of SK channels in cardiomyocytes. Super-resolution imaging of SK2, Ca v 1.2 Ca 2+ channel, and ryanodine receptor 2 (RyR2) was performed to quantify the nearest neighbor distances (NND) and localized the three molecules within hundreds of nanometers. The distribution of NND between SK2 and RyR2 as well as SK2 and Ca v 1.2 was bimodal, suggesting a spatial relationship between the channels. The activation mechanism revealed by our study paved the way for the understanding of the roles of SK channels on the feedback mechanism to regulate the activities of LTCCs and RyR2 to influence local and global Ca 2+ signaling.
The mid-face of lower Pleistocene hominins and its bearing on the attribution of SK 847 and StW 53.
Williams, Frank L'engle; Schroeder, Lauren; Ackermann, Rebecca Rogers
2012-08-01
SK 847 and StW 53 have often been cited as evidence for early Homo in South Africa. To examine whether midfacial morphology is in agreement with these attributions, we analyze Euclidean distances calculated from 3-D coordinates on the maxillae of SK 847 and StW 53, as well as Australopithecus africanus (Sts 5, Sts 71), Paranthropus robustus (SK 46, SK 48, SK 52, SK 83), early Homo (KNM-ER 1813, KNM-ER 1805, KNM-ER 3733, KNM-WT 15000), P. boisei (KNM-ER 406, KNM-WT 17000, KNM-WT 17400), Gorilla gorilla (n=116), Homo sapiens (n=342), Pan paniscus (n=21) and P. troglodytes (n=65). Multivariate analyses separate extant hominoids suggesting we have captured taxonomic affinity. With the exception of SK 847 and SK 52, South African fossils tend to cluster together. P. robustus differs substantially from East African robust megadonts. SK 847 and StW 53 resemble the East African Homo specimens that are the most australopith-like, such as KNM-WT 15000 and KNM-ER 1813. The resemblance between StW 53 and Homo is driven partly by similarities in maxillary size. When distances are scaled, StW 53 aligns with A. africanus, while SK 847 clusters primarily with early Homo. Copyright © 2012 Elsevier GmbH. All rights reserved.
Cytoarchitecture of Zika virus infection in human neuroblastoma and Aedes albopictus cell lines.
Offerdahl, Danielle K; Dorward, David W; Hansen, Bryan T; Bloom, Marshall E
2017-01-15
The Zika virus (ZIKV) pandemic is a global concern due to its role in the development of congenital anomalies of the central nervous system. This mosquito-borne flavivirus alternates between mammalian and mosquito hosts, but information about the biogenesis of ZIKV is limited. Using a human neuroblastoma cell line (SK-N-SH) and an Aedes albopictus mosquito cell line (C6/36), we characterized ZIKV infection by immunofluorescence, transmission electron microscopy (TEM), and electron tomography (ET) to better understand infection in these disparate host cells. ZIKV replicated well in both cell lines, but infected SK-N-SH cells suffered a lytic crisis. Flaviviruses scavenge host cell membranes to serve as replication platforms and ZIKV showed the hallmarks of this process. Via TEM, we identified virus particles and 60-100nm spherular vesicles. ET revealed these vesicular replication compartments contain smaller 20-30nm spherular structures. Our studies indicate that SK-N-SH and C6/36 cells are relevant models for viral cytoarchitecture study. Published by Elsevier Inc.
Apoptosis in the areas of squamous differentiation of irritated seborrheic keratosis.
Pesce, C; Scalora, S
2000-03-01
Seborrheic keratosis (SK) consists of a localized proliferation of basaloid keratinocytes, often accompanied by hyperkeratosis and hyperpigmentation. In irritated SK, these features are associated with areas of squamous differentiation with larger keratinocytes and squamous cell eddies. This work is concerned with the evaluation of apoptosis, as demonstrated by the TUNEL method, in the different varieties of SK. Apoptosis was highly expressed in the areas of squamous differentiation of irritated SK, but only mildly increased in the other varieties of SK. These data support the hypothesis that apoptosis has a role in the squamous differentiation of irritated SK. In consideration also of previous data showing that irritated SK is associated with downregulation of EGF-R expression and 125I-EGF binding, we postulate that the morphologic features of irritated SK could correspond to an involution phase of the disease, characterized by altered cell balance with inadequate cell renewal and increased cell loss.
Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation
Gaviglio, Angela L.; Knelson, Erik H.; Blobe, Gerard C.
2017-01-01
High-risk neuroblastoma is characterized by undifferentiated neuroblasts and low schwannian stroma content. The tumor stroma contributes to the suppression of tumor growth by releasing soluble factors that promote neuroblast differentiation. Here we identify heparin-binding epidermal growth factor–like growth factor (HBEGF) as a potent prodifferentiating factor in neuroblastoma. HBEGF mRNA expression is decreased in human neuroblastoma tumors compared with benign tumors, with loss correlating with decreased survival. HBEGF protein is expressed only in stromal compartments of human neuroblastoma specimens, with tissue from high-stage disease containing very little stroma or HBEGF expression. In 3 human neuroblastoma cell lines (SK-N-AS, SK-N-BE2, and SH-SY5Y), soluble HBEGF is sufficient to promote neuroblast differentiation and decrease proliferation. Heparan sulfate proteoglycans and heparin derivatives further enhance HBEGF-induced differentiation by forming a complex with the epidermal growth factor receptor, leading to activation of the ERK1/2 and STAT3 pathways and up-regulation of the inhibitor of DNA binding transcription factor. These data support a role for loss of HBEGF in the neuroblastoma tumor microenvironment in neuroblastoma pathogenesis.—Gaviglio, A. L., Knelson, E. H., Blobe, G. C. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation. PMID:28174207
ERIC Educational Resources Information Center
Stockdale, Margaret S.; Hope, Kathryn G.
1997-01-01
Factor analysis of data from 1,070 federal employees, 575 undergraduates and 575 graduate students, faculty, and staff uncovered some weaknesses in the Merit Systems Protection Board's sexual harassment survey instrument. This type of survey does not adequately measure sexual coercion or quid pro quo forms of harassment. (SK)
Investigating biological activity spectrum for novel quinoline analogues.
Musiol, Robert; Jampilek, Josef; Kralova, Katarina; Richardson, Des R; Kalinowski, Danuta; Podeszwa, Barbara; Finster, Jacek; Niedbala, Halina; Palka, Anna; Polanski, Jaroslaw
2007-02-01
The lack of the wide spectrum of biological data is an important obstacle preventing the efficient molecular design. Quinoline derivatives are known to exhibit a variety of biological effects. In the current publication, we tested a series of novel quinoline analogues for their photosynthesis-inhibiting activity (the inhibition of photosynthetic electron transport in spinach chloroplasts (Spinacia oleracea L.) and the reduction of chlorophyll content in Chlorella vulgaris Beij.). Moreover, antiproliferative activity was measured using SK-N-MC neuroepithelioma cell line. We described the structure-activity relationships (SAR) between the chemical structure and biological effects of the synthesized compounds. We also measured the lipophilicity of the novel compounds by means of the RP-HPLC and illustrate the relationships between the RP-HPLC retention parameter logK (the logarithm of capacity factor K) and logP data calculated by available programs.
Argyri, Letta; Dafnis, Ioannis; Theodossiou, Theodossis A; Gantz, Donald; Stratikos, Efstratios; Chroni, Angeliki
2014-05-02
The apolipoprotein (apo) E4 isoform has consistently emerged as a susceptibility factor for late-onset Alzheimer disease (AD), although the exact mechanism is not clear. A rare apoE4 mutant, apoE4[L28P] Pittsburgh, burdens carriers with an added risk for late-onset AD and may be a useful tool for gaining insights into the role of apoE4 in disease pathogenesis. Toward this end, we evaluated the effect of the L28P mutation on the structural and functional properties of apoE4. ApoE4[L28P] was found to have significantly perturbed thermodynamic properties, to have reduced helical content, and to expose a larger portion of the hydrophobic surface to the solvent. Furthermore, this mutant is thermodynamically destabilized and more prone to proteolysis. When interacting with lipids, apoE4[L28P] formed populations of lipoprotein particles with structural defects. The structural perturbations brought about by the mutation were accompanied by aberrant functions associated with the pathogenesis of AD. Specifically, apoE4[L28P] promoted the cellular uptake of extracellular amyloid β peptide 42 (Aβ42) by human neuroblastoma SK-N-SH cells as well as by primary mouse neuronal cells and led to increased formation of intracellular reactive oxygen species that persisted for at least 24 h. Furthermore, lipoprotein particles containing apoE4[L28P] induced intracellular reactive oxygen species formation and reduced SK-N-SH cell viability. Overall, our findings suggest that the L28P mutation leads to significant structural and conformational perturbations in apoE4 and can induce functional defects associated with neuronal Aβ42 accumulation and oxidative stress. We propose that these structural and functional changes underlie the observed added risk for AD development in carriers of apoE4[L28P].
Ghazanfari, Nazanin; Morsch, Marco; Reddel, Stephen W; Liang, Simon X; Phillips, William D
2014-01-01
Muscle-specific kinase (MuSK) autoantibodies from myasthenia gravis patients can block the activation of MuSK in vitro and/or reduce the postsynaptic localization of MuSK. Here we use a mouse model to examine the effects of MuSK autoantibodies upon some key components of the postsynaptic MuSK pathway and upon the regulation of junctional ACh receptor (AChR) numbers. Mice became weak after 14 daily injections of anti-MuSK-positive patient IgG. The intensity and area of AChR staining at the motor endplate was markedly reduced. Pulse-labelling of AChRs revealed an accelerated loss of pre-existing AChRs from postsynaptic AChR clusters without a compensatory increase in incorporation of (newly synthesized) replacement AChRs. Large, postsynaptic AChR clusters were replaced by a constellation of tiny AChR microaggregates. Puncta of AChR staining also appeared in the cytoplasm beneath the endplate. Endplate staining for MuSK, activated Src, rapsyn and AChR were all reduced in intensity. In the tibialis anterior muscle there was also evidence that phosphorylation of the AChR β-subunit-Y390 was reduced at endplates. In contrast, endplate staining for β-dystroglycan (through which rapsyn couples AChR to the synaptic basement membrane) remained intense. The results suggest that anti-MuSK IgG suppresses the endplate density of MuSK, thereby down-regulating MuSK signalling activity and the retention of junctional AChRs locally within the postsynaptic membrane scaffold. PMID:24860174
Guidelines for pre-clinical animal and cellular models of MuSK-myasthenia gravis.
Phillips, W D; Christadoss, P; Losen, M; Punga, A R; Shigemoto, K; Verschuuren, J; Vincent, A
2015-08-01
Muscle-specific tyrosine kinase (MuSK) autoantibodies are the hallmark of a form of myasthenia gravis (MG) that can challenge the neurologist and the experimentalist. The clinical disease can be difficult to treat effectively. MuSK autoantibodies affect the neuromuscular junction in several ways. When added to muscle cells in culture, MuSK antibodies disperse acetylcholine receptor clusters. Experimental animals actively immunized with MuSK develop MuSK autoantibodies and muscle weakness. Weakness is associated with reduced postsynaptic acetylcholine receptor numbers, reduced amplitudes of miniature endplate potentials and endplate potentials, and failure of neuromuscular transmission. Similar impairments have been found in mice injected with IgG from MG patients positive for MuSK autoantibody (MuSK-MG). The active and passive models have begun to reveal the mechanisms by which MuSK antibodies disrupt synaptic function at the neuromuscular junction, and should be valuable in developing therapies for MuSK-MG. However, translation into new and improved treatments for patients requires procedures that are not too cumbersome but suitable for examining different aspects of MuSK function and the effects of potential therapies. Study design, conduct and analysis should be carefully considered and transparently reported. Here we review what has been learnt from animal and culture models of MuSK-MG, and offer guidelines for experimental design and conduct of studies, including sample size determination, randomization, outcome parameters and precautions for objective data analysis. These principles may also be relevant to the increasing number of other antibody-mediated diseases that are now recognized. Copyright © 2014 Elsevier Inc. All rights reserved.
Understanding Employee Motivation.
ERIC Educational Resources Information Center
Lindner, James R.
1998-01-01
Extension employees (n=23) ranked the following as the most important motivational factors: interesting work, good wages, appreciation, job security, and good working conditions. The findings were related to theories of motivation formulated by Herzberg, Adams, and Vroom. (SK)
Constant envelope OFDM scheme for 6PolSK-QPSK
NASA Astrophysics Data System (ADS)
Li, Yupeng; Ding, Ding
2018-03-01
A constant envelope OFDM scheme with phase modulator (PM-CE-OFDM) for 6PolSK-QPSK modulation was demonstrated. Performance under large fiber launch power is measured to check its advantages in counteracting fiber nonlinear impairments. In our simulation, PM-CE-OFDM, RF-assisted constant envelope OFDM (RF-CE-OFDM) and conventional OFDM (Con-OFDM) are transmitted through 80 km standard single mode fiber (SSMF) single channel and WDM system. Simulation results confirm that PM-CE-OFDM has best performance in resisting fiber nonlinearity. In addition, benefiting from the simple system structure, the complexity and cost of PM-CE-OFDM system could be reduced effectively.
There is evidence that specificity protein 1 (Sp1) transcription factor (TF) regulates expression of long non-coding RNAs (lncRNAs) in hepatocellular carcinoma (HCC) cells. RNA interference (RNAi) studies showed that among several lncRNAs expressed in HepG2, SNU-449 and SK-Hep-1...
Developments in damage assessment by Marie Skłodowska-Curie TRUSS ITN project
NASA Astrophysics Data System (ADS)
González, A.
2017-05-01
The growth of cities, the impacts of climate change and the massive cost of providing new infrastructure provide the impetus for TRUSS (Training in Reducing Uncertainty in Structural Safety), a €3.7 million Marie Skłodowska-Curie Action Innovative Training Network project funded by EU’s Horizon 2020 programme, which aims to maximize the potential of infrastructure that already exists (http://trussitn.eu). For that purpose, TRUSS brings together an international, inter-sectoral and multidisciplinary collaboration between five academic and eleven industry institutions from five European countries. The project covers rail and road infrastructure, buildings and energy and marine infrastructure. This paper reports progress in fields such as advanced sensor-based structural health monitoring solutions - unmanned aerial vehicles, optical backscatter reflectometry, monitoring sensors mounted on vehicles, … - and innovative algorithms for structural designs and short- and long-term assessments of buildings, bridges, pavements, ships, ship unloaders, nuclear components and wind turbine towers that will support infrastructure operators and owners in managing their assets.
The Persistence of Gender Earnings Inequality in Taiwan, 1978-1992.
ERIC Educational Resources Information Center
Zveglich, Joseph E., Jr.; And Others
1997-01-01
Despite rapid structural change in Taiwan, the gender earnings ratio between 1978-82 remained at 65%. Women's relative gains in education and experience were apparently offset by an increase in wage discrimination. (SK)
Unleashing the Power of Learning. An Interview with British Petroleum's John Browne.
ERIC Educational Resources Information Center
Prokesch, Steven E.
1997-01-01
British Petroleum's chief executive officer explains how the organization was redesigned to foster learning. Key topics include clear purpose, shared knowledge, distinctive relationships, breakthrough thinking, and peer team structure. (SK)
Why It Took So Long to Invent the Aeroplane.
ERIC Educational Resources Information Center
Rodriguez, Charles L.; Most, Michael
1995-01-01
Four major elements of airplanes had to be developed in order to achieve flight. The critical design mix of lift, propulsion, control, and structure was achieved through the work of many pioneers. (SK)
The ILO towards the Twenty-First Century.
ERIC Educational Resources Information Center
Labour Education, 1993
1993-01-01
This position statement outlines the major challenges facing labor education (human rights, employment, structural transition, poverty, marginalization, globalization) and areas for International Labour Organisation action (standards, technical cooperation, sectoral activities, research, publications, and communications). (SK)
Comparing two tetraalkylammonium ionic liquids. I. Liquid phase structure.
Lima, Thamires A; Paschoal, Vitor H; Faria, Luiz F O; Ribeiro, Mauro C C; Giles, Carlos
2016-06-14
X-ray scattering experiments at room temperature were performed for the ionic liquids n-butyl-trimethylammonium bis(trifluoromethanesulfonyl)imide, [N1114][NTf2], and methyl-tributylammonium bis(trifluoromethanesulfonyl)imide, [N1444][NTf2]. The peak in the diffraction data characteristic of charge ordering in [N1444][NTf2] is shifted to longer distances in comparison to [N1114][NTf2], but the peak characteristic of short-range correlations is shifted in [N1444][NTf2] to shorter distances. Molecular dynamics (MD) simulations were performed for these ionic liquids using force fields available from the literature, although with new sets of partial charges for [N1114](+) and [N1444](+) proposed in this work. The shifting of charge and adjacency peaks to opposite directions in these ionic liquids was found in the static structure factor, S(k), calculated by MD simulations. Despite differences in cation sizes, the MD simulations unravel that anions are allowed as close to [N1444](+) as to [N1114](+) because anions are located in between the angle formed by the butyl chains. The more asymmetric molecular structure of the [N1114](+) cation implies differences in partial structure factors calculated for atoms belonging to polar or non-polar parts of [N1114][NTf2], whereas polar and non-polar structure factors are essentially the same in [N1444][NTf2]. Results of this work shed light on controversies in the literature on the liquid structure of tetraalkylammonium based ionic liquids.
Comparing two tetraalkylammonium ionic liquids. I. Liquid phase structure
NASA Astrophysics Data System (ADS)
Lima, Thamires A.; Paschoal, Vitor H.; Faria, Luiz F. O.; Ribeiro, Mauro C. C.; Giles, Carlos
2016-06-01
X-ray scattering experiments at room temperature were performed for the ionic liquids n-butyl-trimethylammonium bis(trifluoromethanesulfonyl)imide, [N1114][NTf2], and methyl-tributylammonium bis(trifluoromethanesulfonyl)imide, [N1444][NTf2]. The peak in the diffraction data characteristic of charge ordering in [N1444][NTf2] is shifted to longer distances in comparison to [N1114][NTf2], but the peak characteristic of short-range correlations is shifted in [N1444][NTf2] to shorter distances. Molecular dynamics (MD) simulations were performed for these ionic liquids using force fields available from the literature, although with new sets of partial charges for [N1114]+ and [N1444]+ proposed in this work. The shifting of charge and adjacency peaks to opposite directions in these ionic liquids was found in the static structure factor, S(k), calculated by MD simulations. Despite differences in cation sizes, the MD simulations unravel that anions are allowed as close to [N1444]+ as to [N1114]+ because anions are located in between the angle formed by the butyl chains. The more asymmetric molecular structure of the [N1114]+ cation implies differences in partial structure factors calculated for atoms belonging to polar or non-polar parts of [N1114][NTf2], whereas polar and non-polar structure factors are essentially the same in [N1444][NTf2]. Results of this work shed light on controversies in the literature on the liquid structure of tetraalkylammonium based ionic liquids.
The hSK4 (KCNN4) isoform is the Ca2+-activated K+ channel (Gardos channel) in human red blood cells.
Hoffman, Joseph F; Joiner, William; Nehrke, Keith; Potapova, Olga; Foye, Kristen; Wickrema, Amittha
2003-06-10
The question is, does the isoform hSK4, also designated KCNN4, represent the small conductance, Ca2+-activated K+ channel (Gardos channel) in human red blood cells? We have analyzed human reticulocyte RNA by RT-PCR, and, of the four isoforms of SK channels known, only SK4 was found. Northern blot analysis of purified and synchronously growing human erythroid progenitor cells, differentiating from erythroblasts to reticulocytes, again showed only the presence of SK4. Western blot analysis, with an anti-SK4 antibody, showed that human erythroid progenitor cells and, importantly, mature human red blood cell ghost membranes, both expressed the SK4 protein. The Gardos channel is known to turn on, given inside Ca2+, in the presence but not the absence of external Ko+ and remains refractory to Ko+ added after exposure to inside Ca2+. Heterologously expressed SK4, but not SK3, also shows this behavior. In inside-out patches of red cell membranes, the open probability (Po) of the Gardos channel is markedly reduced when the temperature is raised from 27 to 37 degrees C. Net K+ efflux of intact red cells is also reduced by increasing temperature, as are the Po values of inside-out patches of Chinese hamster ovary cells expressing SK4 (but not SK3). Thus the envelope of evidence indicates that SK4 is the gene that codes for the Gardos channel in human red blood cells. This channel is important pathophysiologically, because it represents the major pathway for cell shrinkage via KCl and water loss that occurs in sickle cell disease.
Ghazanfari, Nazanin; Morsch, Marco; Reddel, Stephen W; Liang, Simon X; Phillips, William D
2014-07-01
Muscle-specific kinase (MuSK) autoantibodies from myasthenia gravis patients can block the activation of MuSK in vitro and/or reduce the postsynaptic localization of MuSK. Here we use a mouse model to examine the effects of MuSK autoantibodies upon some key components of the postsynaptic MuSK pathway and upon the regulation of junctional ACh receptor (AChR) numbers. Mice became weak after 14 daily injections of anti-MuSK-positive patient IgG. The intensity and area of AChR staining at the motor endplate was markedly reduced. Pulse-labelling of AChRs revealed an accelerated loss of pre-existing AChRs from postsynaptic AChR clusters without a compensatory increase in incorporation of (newly synthesized) replacement AChRs. Large, postsynaptic AChR clusters were replaced by a constellation of tiny AChR microaggregates. Puncta of AChR staining also appeared in the cytoplasm beneath the endplate. Endplate staining for MuSK, activated Src, rapsyn and AChR were all reduced in intensity. In the tibialis anterior muscle there was also evidence that phosphorylation of the AChR β-subunit-Y390 was reduced at endplates. In contrast, endplate staining for β-dystroglycan (through which rapsyn couples AChR to the synaptic basement membrane) remained intense. The results suggest that anti-MuSK IgG suppresses the endplate density of MuSK, thereby down-regulating MuSK signalling activity and the retention of junctional AChRs locally within the postsynaptic membrane scaffold. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.
McNaughton, Melissa; Pitman, Melissa; Pitson, Stuart M; Pyne, Nigel J; Pyne, Susan
2016-03-29
Sphingosine kinases (two isoforms termed SK1 and SK2) catalyse the formation of the bioactive lipid sphingosine 1-phosphate. We demonstrate here that the SK2 inhibitor, ABC294640 (3-(4-chlorophenyl)-adamantane-1-carboxylic acid (pyridin-4-ylmethyl)amide) or the SK1/SK2 inhibitor, SKi (2-(p-hydroxyanilino)-4-(p-chlorophenyl)thiazole)) induce the proteasomal degradation of SK1a (Mr = 42 kDa) and inhibit DNA synthesis in androgen-independent LNCaP-AI prostate cancer cells. These effects are recapitulated by the dihydroceramide desaturase (Des1) inhibitor, fenretinide. Moreover, SKi or ABC294640 reduce Des1 activity in Jurkat cells and ABC294640 induces the proteasomal degradation of Des1 (Mr = 38 kDa) in LNCaP-AI prostate cancer cells. Furthermore, SKi or ABC294640 or fenretinide increase the expression of the senescence markers, p53 and p21 in LNCaP-AI prostate cancer cells. The siRNA knockdown of SK1 or SK2 failed to increase p53 and p21 expression, but the former did reduce DNA synthesis in LNCaP-AI prostate cancer cells. Moreover, N-acetylcysteine (reactive oxygen species scavenger) blocked the SK inhibitor-induced increase in p21 and p53 expression but had no effect on the proteasomal degradation of SK1a. In addition, siRNA knockdown of Des1 increased p53 expression while a combination of Des1/SK1 siRNA increased the expression of p21. Therefore, Des1 and SK1 participate in regulating LNCaP-AI prostate cancer cell growth and this involves p53/p21-dependent and -independent pathways. Therefore, we propose targeting androgen-independent prostate cancer cells with compounds that affect Des1/SK1 to modulate both de novo and sphingolipid rheostat pathways in order to induce growth arrest.
Weng, Mao-Chi; Wang, Mei-Hui; Tsai, Jai-Jen; Kuo, Yu-Cheng; Liu, Yu-Chang; Hsu, Fei-Ting; Wang, Hsin-Ell
2018-06-29
Regorafenib has been demonstrated in our previous study to trigger apoptosis through suppression of extracellular signal-regulated kinase (ERK)/nuclear factor-κB (NF-κB) activation in hepatocellular carcinoma (HCC) SK-Hep1 cells in vitro However, the effect of regorafenib on NF-κB-modulated tumor progression in HCC in vivo is ambiguous. The aim of the present study is to investigate the effect of regorafenib on NF-κB-modulated tumor progression in HCC bearing mouse model. pGL4.50 luciferase reporter vector transfected SK-Hep1 (SK-Hep1/ luc2 ) and Hep3B 2.1-7 tumor bearing mice were established and used for the present study. Mice were treated with vehicle or regorafenib (20 mg/kg/day by gavage) for 14 days. Effects of regorafenib on tumor growth and protein expression together with toxicity of regorafenib were evaluated with digital caliper and bioluminescence imaging (BLI), ex vivo Western blotting immunohistochemistry (IHC) staining, and measurement of body weight and pathological examination of liver tissue, respectively, in SK-Hep1/ luc2 and Hep3B 2.1-7 tumor bearing mice. The results indicated regorafenib significantly reduced tumor growth and expression of phosphorylated ERK, NF-κB p65 (Ser536), phosphorylated AKT, and tumor progression-associated proteins. In addition, we found regorafenib induced both extrinsic and intrinsic apoptotic pathways. Body weight and liver morphology were not affected by regorafenib treatment. Our findings present the mechanism of tumor progression inhibition by regorafenib is linked to suppression of ERK/NF-κB signaling in SK-Hep1/ luc2 and Hep3B 2.1-7 tumor bearing mice. © 2018 The Author(s).
Ciaraldi, Theodore P.; Nogueira, Leonardo; Coe, Taylor; Perkins, Guy; Hogan, Michael; Maisel, Alan S.; Henry, Robert R.; Ceballos, Guillermo; Villarreal, Francisco
2013-01-01
Background Type 2 diabetes (T2D) and heart failure (HF) are associated with high levels of skeletal muscle (SkM) oxidative stress (OS). Health benefits attributed to flavonoids have been ascribed to antioxidation. However, for flavonoids with similar antioxidant potential, end-biological effects vary widely suggesting other mechanistic venues for reducing OS. Decreases in OS may follow the modulation of key regulatory pathways including antioxidant levels (e.g. glutathione) and enzymes such as mitochondrial superoxide dismutase (SOD2) and catalase. Methods We examined OS-related alterations in SkM in T2D/HF patients (as compared vs. healthy controls) and evaluated the effects of three-month treatment with (−)-epicatechin (Epi) rich cocoa (ERC). To evidence Epi as the mediator of the improved OS profile we examined the effects of pure Epi (vs. water) on SkM OS regulatory systems in a mouse model of insulin resistance and contrasted results vs. normal mice. Results There were severe alterations in OS regulatory systems in T2D/HF SkM as compared with healthy controls. Treatment with ERC induced recovery in glutathione levels and decreases in the nitrotyrosilation and carbonylation of proteins. With treatment, key transcriptional factors translocate into the nucleus leading to increases in SOD2 and catalase protein expression and activity levels. In insulin resistant mice, there were alterations in muscle OS and pure Epi replicated the beneficial effects of ERC found in humans. Conclusions Major perturbations in SkM OS can be reversed with ERC in T2D/HF patients. Epi likely mediates such effects and may provide an effective means to treat conditions associated with tissue OS. PMID:23870648
The Aging Mind Proves Capable of Lifelong Growth.
ERIC Educational Resources Information Center
Goleman, Daniel
1984-01-01
Current research shows that, while fluid intelligence may decline with age, crystallized intelligence continues to rise over the life span. Key factors in maintaining mental capabilities include staying socially involved, being mentally active, and being flexible. (SK)
Teaching Small Business Management in the UK Part I.
ERIC Educational Resources Information Center
Birley, Sue; Gibb, Allan
1984-01-01
Reviews the key factors influencing small business management education in the United Kingdom, particularly government policies encouraging small business development. Postulates a model based on the career cycle and considers training opportunities for various stages. (SK)
Intercultural Communication: A Key Element in Global Strategies.
ERIC Educational Resources Information Center
Spinks, Nelda; Wells, Barron
1997-01-01
Cultural factors in global communication include differences in customs, space, dress, religion, class, work ethic, privacy, and other areas. Language differences in oral, written, and nonverbal communication as well as semantics also complicate intercultural communication. (SK)
Take a Chance on Nursing Mentorships: Enhance Leadership with This Win-Win Strategy.
ERIC Educational Resources Information Center
Owens, Jacqueline K.; Patton, June G.
2003-01-01
Exchanges between a clinically experienced registered nurse undertaking graduate study and her mentor, a nursing professor, illustrate antecedent relationship factors, mentoring phases, outcomes, and the mentoring mindset. (Contains 13 references.) (SK)
Dale, T J; Cryan, J E; Chen, M X; Trezise, D J
2002-11-01
The bee venom toxin apamin is an important drug tool for characterising small conductance Ca(2+)-activated K(+) channels (SK channels). In recombinant expression systems both rSK2 and rSK3 channels are potently blocked by apamin, whilst the sensitivity of SK1 channels is somewhat less clear. In the present study we have conducted a detailed analysis by patch clamp electrophysiology of the effects of apamin on human SK channels (SK1, SK2 and SK3) stably expressed in Chinese hamster ovary (CHO-K1) cells. CHO-K1 cell lines expressing either hSK1, 2 or 3 channels were first validated using specific antibodies and Western blotting. Specific protein bands of a size corresponding to the predicted channel tetramer (approximately 250-290 kDa) were detected. In each cell line, but not wild-type untransfected cells, large, time-independent inwardly rectifying Ca(2+)-dependent K(+) currents were observed under voltage-clamp. In CHO-hSK1, this current was markedly reduced by apamin (IC(50) value 8 nM), however, a significant fraction of the current remained unblocked (39+/-5%), even at saturating concentrations (1 microM apamin). The apamin-sensitive and -insensitive currents possess very similar biophysical and pharmacological properties. Each are Ca(2+)-dependent, inwardly rectify and have relative ionic permeabilities of K(+)>Cs(+)>Li(+)=Na(+). Both components were resistant to block by charybdotoxin and iberiotoxin, known IK and BK channel blockers, but were attenuated by the tricyclic antidepressant cyproheptadine (>95% block at 1 mM). The SK channel opener 1-EBIO could still produce channel activation in the presence of apamin. Importantly, hSK2 and hSK3 channels also exhibit partial apamin sensitivity in our experimental paradigm (IC(50) values of 0.14 nM and 1.1 nM, respectively, and maximal percentage inhibition values of 47+/-7% and 58+/-9%, respectively). Our data indicate that, at least in a recombinant expression system, all three SK channels can be partially apamin-sensitive. The explanation for this finding is presently unclear but may be due to regulatory subunits, phosphorylation or other types of post translational modification. Ascribing particular SK channels to physiological roles using apamin as a drug tool needs to be done cautiously in light of these findings.
Hong, Sung-Hyeok; Tilan, Jason U.; Galli, Susana; Izycka-Swieszewska, Ewa; Polk, Taylor; Horton, Meredith; Mahajan, Akanksha; Christian, David; Jenkins, Shari; Acree, Rachel; Connors, Katherine; Ledo, Phuong; Lu, Congyi; Lee, Yi-Chien; Rodriguez, Olga; Toretsky, Jeffrey A.; Albanese, Chris; Kitlinska, Joanna
2015-01-01
Ewing sarcoma (ES) develops in bones or soft tissues of children and adolescents. The presence of bone metastases is one of the most adverse prognostic factors, yet the mechanisms governing their formation remain unclear. As a transcriptional target of EWS-FLI1, the fusion protein driving ES transformation, neuropeptide Y (NPY) is highly expressed and released from ES tumors. Hypoxia up-regulates NPY and activates its pro-metastatic functions. To test the impact of NPY on ES metastatic pattern, ES cell lines, SK-ES1 and TC71, with high and low peptide release, respectively, were used in an orthotopic xenograft model. ES cells were injected into gastrocnemius muscles of SCID/beige mice, the primary tumors excised, and mice monitored for the presence of metastases. SK-ES1 xenografts resulted in thoracic extra-osseous metastases (67%) and dissemination to bone (50%) and brain (25%), while TC71 tumors metastasized to the lungs (70%). Bone dissemination in SK-ES1 xenografts associated with increased NPY expression in bone metastases and its accumulation in bone invasion areas. The genetic silencing of NPY in SK-ES1 cells reduced bone degradation. Our study supports the role for NPY in ES bone invasion and provides new models for identifying pathways driving ES metastases to specific niches and testing anti-metastatic therapeutics. PMID:25714031
Introducing Managers to Expert Systems.
ERIC Educational Resources Information Center
Finlay, Paul N.; And Others
1991-01-01
Describes a short course to expose managers to expert systems, consisting of (1) introductory lecture; (2) supervised computer tutorial; (3) lecture and discussion about knowledge structuring and modeling; and (4) small group work on a case study using computers. (SK)
ERIC Educational Resources Information Center
Kimmel, Michael S.
1993-01-01
Definitions of the male role are changing as more men seek fulfillment in family life, redefine success, or attempt to balance family and career. Corporate structure no longer fits the lives of many men, but employers continue to resist change. (SK)
Theoretical analysis of nonnuniform skin effects on drawdown variation
NASA Astrophysics Data System (ADS)
Chen, C.-S.; Chang, C. C.; Lee, M. S.
2003-04-01
Under field conditions, the skin zone surrounding the well screen is rarely uniformly distributed in the vertical direction. To understand such non-uniform skin effects on drawdown variation, we assume the skin factor to be an arbitrary, continuous or piece-wise continuous function S_k(z), and incorporate it into a well hydraulics model for constant rate pumping in a homogeneous, vertically anisotropic, confined aquifer. Solutions of depth-specific drawdown and vertical average drawdown are determined by using the Gram-Schmidt method. The non-uniform effects of S_k(z) in vertical average drawdown are averaged out, and can be represented by a constant skin factor S_k. As a result, drawdown of fully penetrating observation wells can be analyzed by appropriate well hydraulics theories assuming a constant skin factor. The S_k is the vertical average value of S_k(z) weighted by the well bore flux q_w(z). In depth-specific drawdown, however, the non-uniform effects of S_k(z) vary with radial and vertical distances, which are under the influence of the vertical profile of S_k(z) and the vertical anisotropy ratio, K_r/K_z. Therefore, drawdown of partially penetrating observation wells may reflect the vertical anisotropy as well as the non-uniformity of the skin zone. The method of determining S_k(z) developed herein involves the use of q_w(z) as can be measured with the borehole flowmeter, and K_r/K_z and S_k as can be determined by the conventional pumping test.
Bui, Long M G; Kidd, Stephen P
2015-12-01
A key to persistent and recurrent Staphylococcus aureus infections is its ability to adapt to diverse and toxic conditions. This ability includes a switch into a biofilm or to the quasi-dormant Small Colony Variant (SCV). The development and molecular attributes of SCVs have been difficult to study due to their rapid reversion to their parental cell-type. We recently described the unique induction of a matrix-embedded and stable SCV cell-type in a clinical S. aureus strain (WCH-SK2) by growing the cells with limiting conditions for a prolonged timeframe. Here we further study their characteristics. They possessed an increased viability in the presence of antibiotics compared to their non-SCV form. Their stability implied that there had been genetic changes; we therefore determined both the genome sequence of WCH-SK2 and its stable SCV form at a single base resolution, employing Single Molecular Real-Time (SMRT) sequencing that enabled the methylome to also be determined. The genetic features of WCH-SK2 have been identified; the SCCmec type, the pathogenicity and genetic islands and virulence factors. The genetic changes that had occurred in the stable SCV form were identified; most notably being in MgrA, a global regulator, and RsbU, a phosphoserine phosphatase within the regulatory pathway of the sigma factor SigB. There was a shift in the methylomes of the non-SCV and stable SCV forms. We have also shown a similar induction of this cell-type in other S. aureus strains and performed a genetic comparison to these and other S. aureus genomes. We additionally map RNAseq data to the WCH-SK2 genome in a transcriptomic analysis of the parental, SCV and stable SCV cells. The results from this study represent the unique identification of a suite of epigenetic, genetic and transcriptional factors that are implicated in the switch in S. aureus to its persistent SCV form. Copyright © 2015 Elsevier B.V. All rights reserved.
Dissipation processes in the insulating skyrmion compound Cu2OSeO3
NASA Astrophysics Data System (ADS)
Levatić, I.; Šurija, V.; Berger, H.; Živković, I.
2014-12-01
We present a detailed study of the phase diagram surrounding the skyrmion lattice (SkL) phase of Cu2OSe2O3 using high-precision magnetic ac susceptibility measurements. An extensive investigation of transition dynamics around the SkL phase using the imaginary component of the susceptibility revealed that at the conical-to-SkL transition a broad dissipation region exists with a complex frequency dependence. The analysis of the observed behavior within the SkL phase indicates a distribution of relaxation times intrinsically related to SkL. At the SkL-to-paramagnet transition a narrow first-order peak is found that exhibits a strong frequency and magnetic field dependence. Surprisingly, very similar dependence has been discovered for the first-order transition below the SkL phase, i.e., where the system enters the helical and conical state(s), indicating similar processes across the order-disorder transition.
QU, DAN; CHEN, YU; XU, XIAO-MAN; ZHANG, MENG; ZHANG, YI; LI, SHENG-QI
2015-01-01
Shikonin (SK), a naturally occurring naphthoquinone, exhibits antitumor activity. However, its precise mechanisms of action are unknown. In the present study, the effects of SK on NCI-H460 human lung cancer cells were investigated. It was found that SK reduced cell viability and induced apoptosis in the NCI-H460 cells. Additionally, SK inhibited extracellular signal-regulated kinase (ERK) activity, which indicates that inhibition of the ERK pathway is probably one of the mechanisms by which SK induced NCI-H460 cell apoptosis. The expression of Cbl-b was significantly increased by treatment with SK for 4 h, and gradually increased to a maximal level at 24 h; the time taken for the upregulation of Cbl-b protein was in accordance to that required for the downregulation of phospho (p)-ERK protein. The Cbl inhibitor Ps341 reversed the SK-induced downregulation of p-ERK and apoptosis of NCI-H460 cells. These results indicate that Cbl-b potentiates the apoptotic action of SK by inhibiting the ERK pathway in lung cancer cells. PMID:25780420
SK2 channels regulate mitochondrial respiration and mitochondrial Ca2+ uptake.
Honrath, Birgit; Matschke, Lina; Meyer, Tammo; Magerhans, Lena; Perocchi, Fabiana; Ganjam, Goutham K; Zischka, Hans; Krasel, Cornelius; Gerding, Albert; Bakker, Barbara M; Bünemann, Moritz; Strack, Stefan; Decher, Niels; Culmsee, Carsten; Dolga, Amalia M
2017-05-01
Mitochondrial calcium ([Ca 2+ ] m ) overload and changes in mitochondrial metabolism are key players in neuronal death. Small conductance calcium-activated potassium (SK) channels provide protection in different paradigms of neuronal cell death. Recently, SK channels were identified at the inner mitochondrial membrane, however, their particular role in the observed neuroprotection remains unclear. Here, we show a potential neuroprotective mechanism that involves attenuation of [Ca 2+ ] m uptake upon SK channel activation as detected by time lapse mitochondrial Ca 2+ measurements with the Ca 2+ -binding mitochondria-targeted aequorin and FRET-based [Ca 2+ ] m probes. High-resolution respirometry revealed a reduction in mitochondrial respiration and complex I activity upon pharmacological activation and overexpression of mitochondrial SK2 channels resulting in reduced mitochondrial ROS formation. Overexpression of mitochondria-targeted SK2 channels enhanced mitochondrial resilience against neuronal death, and this effect was inhibited by overexpression of a mitochondria-targeted dominant-negative SK2 channel. These findings suggest that SK channels provide neuroprotection by reducing [Ca 2+ ] m uptake and mitochondrial respiration in conditions, where sustained mitochondrial damage determines progressive neuronal death.
SK2 channels regulate mitochondrial respiration and mitochondrial Ca2+ uptake
Honrath, Birgit; Matschke, Lina; Meyer, Tammo; Magerhans, Lena; Perocchi, Fabiana; Ganjam, Goutham K; Zischka, Hans; Krasel, Cornelius; Gerding, Albert; Bakker, Barbara M; Bünemann, Moritz; Strack, Stefan; Decher, Niels; Culmsee, Carsten; Dolga, Amalia M
2017-01-01
Mitochondrial calcium ([Ca2+]m) overload and changes in mitochondrial metabolism are key players in neuronal death. Small conductance calcium-activated potassium (SK) channels provide protection in different paradigms of neuronal cell death. Recently, SK channels were identified at the inner mitochondrial membrane, however, their particular role in the observed neuroprotection remains unclear. Here, we show a potential neuroprotective mechanism that involves attenuation of [Ca2+]m uptake upon SK channel activation as detected by time lapse mitochondrial Ca2+ measurements with the Ca2+-binding mitochondria-targeted aequorin and FRET-based [Ca2+]m probes. High-resolution respirometry revealed a reduction in mitochondrial respiration and complex I activity upon pharmacological activation and overexpression of mitochondrial SK2 channels resulting in reduced mitochondrial ROS formation. Overexpression of mitochondria-targeted SK2 channels enhanced mitochondrial resilience against neuronal death, and this effect was inhibited by overexpression of a mitochondria-targeted dominant-negative SK2 channel. These findings suggest that SK channels provide neuroprotection by reducing [Ca2+]m uptake and mitochondrial respiration in conditions, where sustained mitochondrial damage determines progressive neuronal death. PMID:28282037
Diverging roles for Lrp4 and Wnt signaling in neuromuscular synapse development during evolution.
Remédio, Leonor; Gribble, Katherine D; Lee, Jennifer K; Kim, Natalie; Hallock, Peter T; Delestrée, Nicolas; Mentis, George Z; Froemke, Robert C; Granato, Michael; Burden, Steven J
2016-05-01
Motor axons approach muscles that are prepatterned in the prospective synaptic region. In mice, prepatterning of acetylcholine receptors requires Lrp4, a LDLR family member, and MuSK, a receptor tyrosine kinase. Lrp4 can bind and stimulate MuSK, strongly suggesting that association between Lrp4 and MuSK, independent of additional ligands, initiates prepatterning in mice. In zebrafish, Wnts, which bind the Frizzled (Fz)-like domain in MuSK, are required for prepatterning, suggesting that Wnts may contribute to prepatterning and neuromuscular development in mammals. We show that prepatterning in mice requires Lrp4 but not the MuSK Fz-like domain. In contrast, prepatterning in zebrafish requires the MuSK Fz-like domain but not Lrp4. Despite these differences, neuromuscular synapse formation in zebrafish and mice share similar mechanisms, requiring Lrp4, MuSK, and neuronal Agrin but not the MuSK Fz-like domain or Wnt production from muscle. Our findings demonstrate that evolutionary divergent mechanisms establish muscle prepatterning in zebrafish and mice. © 2016 Remédio et al.; Published by Cold Spring Harbor Laboratory Press.
Influence of Melanosome Dynamics on Melanoma Drug Sensitivity
Chen, Kevin G.; Leapman, Richard D.; Zhang, Guofeng; Lai, Barry; Valencia, Julio C.; Cardarelli, Carol O.; Vieira, Wilfred D.; Hearing, Vincent J.
2009-01-01
Background Malignant melanomas are intrinsically resistant to many conventional treatments, such as radiation and chemotherapy, for reasons that are poorly understood. Here we propose and test a model that explains drug resistance or sensitivity in terms of melanosome dynamics. Methods The growth and sensitivity to cisplatin of MNT-1 cells, which are melanotic and enriched with mature stage III and IV melanosomes, and SK-MEL-28 cells, which have only immature stage I and II melanosomes, were compared using clonogenic assays. Differences in pigmentation, melanosome stages, melanosome number, and cellular structures in different cell lines in response to various treatments were examined by electron microscopy. The relative numbers of melanosomes of different stages were compared after treatment with 1-phenyl-2-thiourea. The relationship between drug transporter function and endogenous melanogenic toxicity was assessed by treating cells with the cyclosporin analog PSC-833 and by assessing vacuole formation and cell growth inhibition. All statistical tests were two-sided. Results Endogenous melanogenic cytotoxicity, produced by damaged melanosomes, resulted in pronounced cell growth inhibition in MNT-1 cells compared with amelanotic SK-MEL-28 cells. The sensitivity to CDDP of MNT-1 cells was 3.8-fold higher than that of SK-MEL-28 cells (mean IC50 for SK-MEL-28 and MNT-1 = 2.13 μM and 0.56 μM, respectively; difference = 1.57 μM, 95% confidence interval = 1.45 to 1.69; P = .0017). After treatment with 6.7 μM CDDP for 72 hours, the number of stage II-III melanosomes in surviving MNT-1 cells was 6.8-fold that of untreated cells. Modulation of MNT-1 cells to earlier-stage (II, II-III, III) melanosomes by treatment with the tyrosinase inhibitor 1-phenyl-2-thiourea dramatically increased CDDP resistance. Furthermore, PSC-833 principally suppressed MNT-1 melanotic cell growth via an elevation of autophagosome-like vacuolar structures, possibly by inhibiting melanosome membrane transporters. Conclusions Melanosome dynamics (including their biogenesis, density, status, and structural integrity) regulate the drug resistance of melanoma cells. Manipulation of melanosome functions may be an effective way to enhance the therapeutic activity of anticancer drugs against melanoma. PMID:19704071
Influence of melanosome dynamics on melanoma drug sensitivity.
Chen, Kevin G; Leapman, Richard D; Zhang, Guofeng; Lai, Barry; Valencia, Julio C; Cardarelli, Carol O; Vieira, Wilfred D; Hearing, Vincent J; Gottesman, Michael M
2009-09-16
Malignant melanomas are intrinsically resistant to many conventional treatments, such as radiation and chemotherapy, for reasons that are poorly understood. Here we propose and test a model that explains drug resistance or sensitivity in terms of melanosome dynamics. The growth and sensitivity to cisplatin of MNT-1 cells, which are melanotic and enriched with mature stage III and IV melanosomes, and SK-MEL-28 cells, which have only immature stage I and II melanosomes, were compared using clonogenic assays. Differences in pigmentation, melanosome stages, melanosome number, and cellular structures in different cell lines in response to various treatments were examined by electron microscopy. The relative numbers of melanosomes of different stages were compared after treatment with 1-phenyl-2-thiourea. The relationship between drug transporter function and endogenous melanogenic toxicity was assessed by treating cells with the cyclosporin analog PSC-833 and by assessing vacuole formation and cell growth inhibition. All statistical tests were two-sided. Endogenous melanogenic cytotoxicity, produced by damaged melanosomes, resulted in pronounced cell growth inhibition in MNT-1 cells compared with amelanotic SK-MEL-28 cells. The sensitivity to CDDP of MNT-1 cells was 3.8-fold higher than that of SK-MEL-28 cells (mean IC(50) for SK-MEL-28 and MNT-1 = 2.13 microM and 0.56 microM, respectively; difference = 1.57 microM, 95% confidence interval = 1.45 to 1.69; P = .0017). After treatment with 6.7 microM CDDP for 72 hours, the number of stage II-III melanosomes in surviving MNT-1 cells was 6.8-fold that of untreated cells. Modulation of MNT-1 cells to earlier-stage (II, II-III, III) melanosomes by treatment with the tyrosinase inhibitor 1-phenyl-2-thiourea dramatically increased CDDP resistance. Furthermore, PSC-833 principally suppressed MNT-1 melanotic cell growth via an elevation of autophagosome-like vacuolar structures, possibly by inhibiting melanosome membrane transporters. Melanosome dynamics (including their biogenesis, density, status, and structural integrity) regulate the drug resistance of melanoma cells. Manipulation of melanosome functions may be an effective way to enhance the therapeutic activity of anticancer drugs against melanoma.
A Course in Heterogeneous Catalysis: Principles, Practice, and Modern Experimental Techniques.
ERIC Educational Resources Information Center
Wolf, Eduardo E.
1981-01-01
Outlines a multidisciplinary course which comprises fundamental, practical, and experimental aspects of heterogeneous catalysis. The course structure is a combination of lectures and demonstrations dealing with the use of spectroscopic techniques for surface analysis. (SK)
Implications of Lean Manufacturing for Human Resource Strategy.
ERIC Educational Resources Information Center
Forrester, Rosalind
1995-01-01
Lean production changes organizational style and structure, roles of team leaders and members, training needs, problem-solving approaches, labor relations, and pay practices. The profound cultural changes it causes may trigger defenses that cause it to fail. (SK)
Resource Letter BH-1: Black Holes.
ERIC Educational Resources Information Center
Detweiler, Steven
1981-01-01
Lists resources on black holes, including: (1) articles of historical interest; (2) books and journal articles on elementary expositions; (3) elementary and advanced textbooks; and (4) research articles on analytic structure of black holes, black hole dynamics, and astrophysical processes. (SK)
Postgraduate Education for Nurses: The Middlesex Model.
ERIC Educational Resources Information Center
Caldwell, Kay
2001-01-01
A British university's curriculum model for master's and postgraduate diploma nursing education is characterized by structured collaboration among students, clinical mentors, and academic supervisors. A professional development portfolio individualizes the program and facilitates autonomous learning. (Contains 21 references.) (SK)
Neroev, V V; Archipova, M M; Bakeeva, L E; Fursova, A Zh; Grigorian, E N; Grishanova, A Yu; Iomdina, E N; Ivashchenko, Zh N; Katargina, L A; Khoroshilova-Maslova, I P; Kilina, O V; Kolosova, N G; Kopenkin, E P; Korshunov, S S; Kovaleva, N A; Novikova, Yu P; Philippov, P P; Pilipenko, D I; Robustova, O V; Saprunova, V B; Senin, I I; Skulachev, M V; Sotnikova, L F; Stefanova, N A; Tikhomirova, N K; Tsapenko, I V; Shchipanova, A I; Zinovkin, R A; Skulachev, V P
2008-12-01
Mitochondria-targeted cationic plastoquinone derivative SkQ1 (10-(6'-plastoquinonyl) decyltriphenylphosphonium) has been investigated as a potential tool for treating a number of ROS-related ocular diseases. In OXYS rats suffering from a ROS-induced progeria, very small amounts of SkQ1 (50 nmol/kg per day) added to food were found to prevent development of age-induced cataract and retinopathies of the eye, lipid peroxidation and protein carbonylation in skeletal muscles, as well as a decrease in bone mineralization. Instillation of drops of 250 nM SkQ1 reversed cataract and retinopathies in 3-12-month-old (but not in 24-month-old) OXYS rats. In rabbits, experimental uveitis and glaucoma were induced by immunization with arrestin and injections of hydroxypropyl methyl cellulose to the eye anterior sector, respectively. Uveitis was found to be prevented or reversed by instillation of 250 nM SkQ1 drops (four drops per day). Development of glaucoma was retarded by drops of 5 microM SkQ1 (one drop daily). SkQ1 was tested in veterinarian practice. A totally of 271 animals (dogs, cats, and horses) suffering from retinopathies, uveitis, conjunctivitis, and cornea diseases were treated with drops of 250 nM SkQ1. In 242 cases, positive therapeutic effect was obvious. Among animals suffering from retinopathies, 89 were blind. In 67 cases, vision returned after SkQ1 treatment. In ex vivo studies of cultivated posterior retina sector, it was found that 20 nM SkQ1 strongly decreased macrophagal transformation of the retinal pigmented epithelial cells, an effect which might explain some of the above SkQ1 activities. It is concluded that low concentrations of SkQ1 are promising in treating retinopathies, cataract, uveitis, glaucoma, and some other ocular diseases.
Low-Cost Aircraft Structural Repair and Maintenance Study
1977-03-01
371,311 F- kO 2,011,^1 112,564 C-130E 687,572 137,571 A-7D 185,7^9 24,101 T-38 1,210,680 7,509.865 85,342 865.919 Figure 6. Total AFM66-1...M AIRFRAI IRE^ IE (R 520 PITTED SkO PUNCTURED 070 *• : 585 SHEARED 605 CRAZED 660 STRIPPED 105 i i ! X LOG GEJ 106 I ;- N» FL...520 SkO t ■n >: ^1 00 —♦—- 585 605 660 731 780 846 878 910 4- 917 935 947 Ino t lo ON \\o V*» -F-i-- f I I vo — i-f i ON H
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sekiya, M.; Frohlich, E.D.; Cole, F.E.
1991-01-01
In the present study, we investigated the effects of calmodulin, adenosine 5{prime}-triphosphate (ATP) and pertussis toxin (PT) on phorbol ester (PMA) induced inhibition of ANF-stimulated cyclic GMP formation in cells from the human renal cell line, SK-NEP-1. PMA inhibited ANF-stimulated guanylate cyclase activity in particulate membranes by about 65%. Calmodulin reversed this inhibition in a dose dependent manner. ATP potentiated Mg++ but not Mn++ supported guanylate cyclase activity. In PMA treated membranes, ATP potentiating effects were abolished. PMA also inhibited ANF-stimulated cGMP accumulation, but pretreatment with PT prevented this PMA inhibition. PT did not affect basal or ANF-stimulated cGMP accumulation.more » In conclusion, these results demonstrated that PMA inhibited ANF stimulation of particulate guanylate cyclase in opposition to the activating effects of calmodulin or ATP in SK-NEP-1 cells. The protein kinase C inhibitory effects appeared to be mediated via a PT-sensitive G protein.« less
Kim, Young Kyeung; Mbonye, Uri; Hokello, Joseph; Karn, Jonathan
2011-07-29
Latent human immunodeficiency virus (HIV) proviruses are thought to be primarily reactivated in vivo through stimulation of the T-cell receptor (TCR). Activation of the TCR induces multiple signal transduction pathways, leading to the ordered nuclear migration of the HIV transcription initiation factors NF-κB (nuclear factor κB) and NFAT (nuclear factor of activated T-cells), as well as potential effects on HIV transcriptional elongation. We have monitored the kinetics of proviral reactivation using chromatin immunoprecipitation assays to measure changes in the distribution of RNA polymerase II in the HIV provirus. Surprisingly, in contrast to TNF-α (tumor necrosis factor α) activation, where early transcription elongation is highly restricted due to rate-limiting concentrations of Tat, efficient and sustained HIV elongation and positive transcription elongation factor b (P-TEFb) recruitment are detected immediately after the activation of latent proviruses through the TCR. Inhibition of NFAT activation by cyclosporine had no effect on either HIV transcription initiation or elongation. However, examination of P-TEFb complexes by gel-filtration chromatography showed that TCR signaling led to the rapid dissociation of the large inactive P-TEFb:7SK RNP (small nuclear RNA 7SK ribonucleoprotein) complex and the release of active low-molecular-weight P-TEFb complexes. Both P-TEFb recruitment to the HIV long terminal repeat and enhanced HIV processivity were blocked by the ERK (extracellular-signal-regulated kinase) inhibitor U0126, but not by AKT (serine/threonine protein kinase Akt) and PI3K (phosphatidylinositol 3-kinase) inhibitors. In contrast to treatment with HMBA (hexamethylene bisacetamide) and DRB (5,6-dichlorobenzimidazole 1-β-ribofuranoside), which disrupt the large 7SK RNP complex but do not stimulate early HIV elongation, TCR signaling provides the first example of a physiological pathway that can shift the balance between the inactive P-TEFb pool and the active P-TEFb pool and thereby stimulate proviral reactivation. Copyright © 2011 Elsevier Ltd. All rights reserved.
Wang, Jianxu; Feng, Xinbin; Anderson, Christopher W N; Zhu, Wei; Yin, Runsheng; Wang, Heng
2011-12-01
The level of mercury bioaccumulation in wild plants; the distribution of bioavailable Hg, elemental Hg, and total Hg in soil; and the concentration of total gaseous Hg (TGM) in ambient air was studied at three different mining sites (SiKeng [SK], WuKeng [WK], and GouXi [GX]) in the Wanshan mercury mining district of China. Results of the present study showed that the distribution of soil total Hg, elemental Hg, bioavailable Hg, and TGM varies across the three mining sites. Higher soil total Hg (29.4-1,972.3 mg/kg) and elemental Hg (19.03-443.8 mg/kg) concentrations were recorded for plots SK and WK than for plot GX. Bioavailable Hg was lower at plot SK and GX (SK, 3-12 ng/g; GX, 9-14 ng/g) than at plot WK (11-1,063 ng/g), although the TGM concentration in the ambient air was significantly higher for plot GX (52,723 ng/m(3) ) relative to WK (106 ng/m(3) ) and SK (43 ng/m(3)). Mercury in sampled herbage was elevated and ranged from 0.8 to 4.75 mg/kg (SK), from 2.17 to 34.38 mg/kg (WK), and from 47.45 to 136.5 mg/kg (GX). Many of the sampled plants are used as fodder or for medicinal purposes. High shoot Hg concentrations may therefore pose an unacceptable human health risk. Statistical analysis of the recorded data showed that the Hg concentration in plant shoots was positively correlated with TGM and that the Hg concentration in roots was positively correlated with the bioavailable Hg concentration in the soil. The bioaccumulation factor (BAF) in the present study was defined with reference to the concentration of bioavailable Hg in the soil (Hg([root]) /Hg([bioavail])). Three plant species, Macleaya cordata L., Achillea millefolium L., and Pteris vittata L., showed enhanced accumulation of Hg and therefore may have potential for use in the phytoremediation of soils of the Wanshan mining area. Copyright © 2011 SETAC.
Mechanisms underlying the cardiac pacemaker: the role of SK4 calcium-activated potassium channels
Weisbrod, David; Khun, Shiraz Haron; Bueno, Hanna; Peretz, Asher; Attali, Bernard
2016-01-01
The proper expression and function of the cardiac pacemaker is a critical feature of heart physiology. The sinoatrial node (SAN) in human right atrium generates an electrical stimulation approximately 70 times per minute, which propagates from a conductive network to the myocardium leading to chamber contractions during the systoles. Although the SAN and other nodal conductive structures were identified more than a century ago, the mechanisms involved in the generation of cardiac automaticity remain highly debated. In this short review, we survey the current data related to the development of the human cardiac conduction system and the various mechanisms that have been proposed to underlie the pacemaker activity. We also present the human embryonic stem cell-derived cardiomyocyte system, which is used as a model for studying the pacemaker. Finally, we describe our latest characterization of the previously unrecognized role of the SK4 Ca2+-activated K+ channel conductance in pacemaker cells. By exquisitely balancing the inward currents during the diastolic depolarization, the SK4 channels appear to play a crucial role in human cardiac automaticity. PMID:26725737
Mechanisms underlying the cardiac pacemaker: the role of SK4 calcium-activated potassium channels.
Weisbrod, David; Khun, Shiraz Haron; Bueno, Hanna; Peretz, Asher; Attali, Bernard
2016-01-01
The proper expression and function of the cardiac pacemaker is a critical feature of heart physiology. The sinoatrial node (SAN) in human right atrium generates an electrical stimulation approximately 70 times per minute, which propagates from a conductive network to the myocardium leading to chamber contractions during the systoles. Although the SAN and other nodal conductive structures were identified more than a century ago, the mechanisms involved in the generation of cardiac automaticity remain highly debated. In this short review, we survey the current data related to the development of the human cardiac conduction system and the various mechanisms that have been proposed to underlie the pacemaker activity. We also present the human embryonic stem cell-derived cardiomyocyte system, which is used as a model for studying the pacemaker. Finally, we describe our latest characterization of the previously unrecognized role of the SK4 Ca(2+)-activated K(+) channel conductance in pacemaker cells. By exquisitely balancing the inward currents during the diastolic depolarization, the SK4 channels appear to play a crucial role in human cardiac automaticity.
Industrialisation, Exports and Employment.
ERIC Educational Resources Information Center
Sabolo, Yves
1980-01-01
After reviewing trends in industrial production, exports, and employment in the Third World since 1960, the author discusses industrialization strategies based on the local processing of raw materials for export. Such processing has proved to be a major factor in job creation. (Author/SK)
A Study of Professional Nurses' Perceptions of Patient Education.
ERIC Educational Resources Information Center
Marcum, Julie; Ridenour, Maureen; Shaff, Gaye; Hammons, Mary; Taylor, Monica
2002-01-01
Of 124 acute care nurses, 97% felt that patient education was a priority. Inhibiting factors were time, staffing, and patient receptiveness. Enhancers included having time to teach, receiving effective teaching guidance materials, and having access to teaching resources. (SK)
The Importance of the Act of Going: Towards Gender Inclusive Education.
ERIC Educational Resources Information Center
Rowan, Leonie
1997-01-01
Reviews factors influencing the desire for gender-inclusive educational environments; identifies common responses (token equity, homogenization of women, arguments that women are the same as/different from men). Gives examples of obstacles encountered by profeminist educators. (SK)
NASA Astrophysics Data System (ADS)
Hwang, Jeong-Hye
Part 1. Biochemistry research involves elucidating the mechanism of membrane targeting of human sphingosine kinase 1 (hSK1). Sphingosine kinase (SK) is an enzyme that catalyzes phosphorylation of sphingosine to sphingosine-1-phosphate (S-1-P). hSK1 can be activated by its agonists resulting in rapid and transient increased production of S-1-P, resulting in enhancement of apoptosis. Upon activation by PMA, SK translocates to the plasma membrane. In vitro measurement demonstrated hSK1 selectively bound phosphatidylserine over anionic lipids and showed strong preference for the plasma membrane-mimetics. Mutational analysis of conserved Thr54 and Asn89 on putative membrane-binding surface from the model structure showed both in vivo and in vitro that these two residues are important for the membrane selectivity of hSK1. Part 2. Chemical education research focuses on three different ways of scientific learning and teaching. First, inquiry teaching that involves a writing method called the Science Writing Heuristic (SWH) is analyzed using grounded theory. This is done in a general education course for pre-service teachers. As a result, (1) students experience understanding of concept through mastery of their own methods and experience different aspects of inquiry processes; (2) SWH method allows instructors to detect misconceptions generated by students' incorrect, but logical interpretations of their data, and helps instructors to make changes to guide students; (3) as students experience meta-cognition, students gain understanding of concepts by relating mathematical progression to different parts of the experiments and also by applying what they learn into other situations. Second, statistical analysis on the long term effects of a combined math/chemistry program is analyzed through multiple linear regression and discriminant function analysis. The results demonstrate the program was beneficial to the underrepresented students when the college success was measured using their final GPA and graduation rates. The third chapter analyzes use of a narrative in a classroom as part of the Chicago Public School High School Transformation Project. The analysis using the case study demonstrates how students can connect to scientific concept when it is introduced with something they can relate with.
Managing Excellence in Sports Performance.
ERIC Educational Resources Information Center
Lyle, John W. B.
1997-01-01
Conceptualizes excellence in sports performance and suggests that there is a failure to distinguish between community recreation and performance sports as well as lack of knowledge about talent identification. Proposes a structure for management and investment in education and training in the field. (SK)
Bunda, Jordan; Gittings, William; Vandenboom, Rene
2018-01-30
Phosphorylation of the myosin regulatory light chain (RLC) by skeletal myosin light chain kinase (skMLCK) potentiates rodent fast twitch muscle but is an ATP-requiring process. Our objective was to investigate the effect of skMLCK-catalyzed RLC phosphorylation on the energetic cost of contraction and the contractile economy (ratio of mechanical output to metabolic input) of mouse fast twitch muscle in vitro (25°C). To this end, extensor digitorum longus (EDL) muscles from wild-type (WT) and from skMLCK-devoid (skMLCK -/- ) mice were subjected to repetitive low-frequency stimulation (10 Hz for 15 s) to produce staircase potentiation of isometric twitch force, after which muscles were quick frozen for determination of high-energy phosphate consumption (HEPC). During stimulation, WT muscles displayed significant potentiation of isometric twitch force while skMLCK -/- muscles did not (i.e. 23% versus 5% change, respectively). Consistent with this, RLC phosphorylation was increased ∼3.5-fold from the unstimulated control value in WT but not in skMLCK -/- muscles. Despite these differences, the HEPC of WT muscles was not greater than that of skMLCK -/- muscles. As a result of the increased contractile output relative to HEPC, the calculated contractile economy of WT muscles was greater than that of skMLCK -/- muscles. Thus, our results suggest that skMLCK-catalyzed phosphorylation of the myosin RLC increases the contractile economy of WT mouse EDL muscle compared with skMLCK -/- muscles without RLC phosphorylation. © 2018. Published by The Company of Biologists Ltd.
Mohan, Nishant; Ai, Walden; Chakrabarti, Mrinmay; Banik, Naren L; Ray, Swapan K
2013-06-01
Neuroblastoma is a childhood tumor that arises from immature neuroblasts of the sympathetic nervous system. Krüpple-like factor 4 (KLF4) is a transcription factor, the precise function of which in neuroblastoma is unclear. We examined the effects of KLF4 overexpression and apigenin (APG) treatment in human malignant neuroblastoma SK-N-DZ and IMR-32 cell lines. KLF4 overexpression in both SK-N-DZ and IMR-32 cell lines was confirmed by laser scanning immunofluorescent confocal microscopy and Western blotting. We found that 100 nM KLF4 plasmid and 25 μM APG synergistically inhibited the growth of SK-N-DZ and IMR-32 cells. We also found increase in KLF4 expression in response to treatment with various concentrations of APG. Combination of KLF4 plasmid and APG treatment significantly increased the amounts of apoptosis in both cell lines when compared with control vector or single treatment. We also noticed that the combination therapy decreased expression of the anti-apoptotic proteins Bcl-2 and Mcl-1, increased expression of the pro-apoptotic proteins Bax, Noxa, and Puma, upregulated p53, and caused activation of caspase-3 for cleavage of the inhibitor of caspase-activated DNase (ICAD) leading to completion of apoptosis machinery. Further, combination of KLF4 overexpression and APG treatment was highly effective in inhibiting migration of both neuroblastoma cell lines and was associated with down regulation of matrix metalloproteinases (MMPs) such as MMP-2 and MMP-9. Collectively, our results from this investigation strongly suggest that KLF4 functions as a tumor suppressor and potentiates the anti-cancer activities of APG in two different human malignant neuroblastoma cell lines. Copyright © 2012 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
Ehrlich, Kenneth C.; Paterson, Heather L.; Lacey, Michelle; Ehrlich, Melanie
2016-01-01
Tissue-specific enhancers are critical for gene regulation. In this study, we help elucidate the contribution of muscle-associated differential DNA methylation to the enhancer activity of highly muscle-specific genes. By bioinformatic analysis of 44 muscle-associated genes, we show that preferential gene expression in skeletal muscle (SkM) correlates with SkM-specific intragenic and intergenic enhancer chromatin and overlapping foci of DNA hypomethylation. Some genes, e.g., CASQ1 and FBXO32, displayed broad regions of both SkM- and heart-specific enhancer chromatin but exhibited focal SkM-specific DNA hypomethylation. Half of the genes had SkM-specific super-enhancers. In contrast to simple enhancer/gene-expression correlations, a super-enhancer was associated with the myogenic MYOD1 gene in both SkM and myoblasts even though SkM has < 1 percent as much MYOD1 expression. Local chromatin differences in this super-enhancer probably contribute to the SkM/myoblast differential expression. Transfection assays confirmed the tissue-specificity of the 0.3-kb core enhancer within MYOD1’s super-enhancer and demonstrated its repression by methylation of its three CG dinucleotides. Our study suggests that DNA hypomethylation increases enhancer tissue-specificity and that SkM super-enhancers sometimes are poised for physiologically important, rapid up-regulation. PMID:28018137
Christov, Nikolai Kirilov; Christova, Petya Koeva; Kato, Hideki; Liu, Yuelin; Sasaki, Kentaro; Imai, Ryozo
2014-11-01
A novel cold-inducible GSK3/shaggy-like kinase, TaSK5, was isolated from winter wheat using a macroarray-based differential screening approach. TaSK5 showed high similarity to Arabidopsis subgroup I GSK3/shaggy-like kinases ASK-alpha, AtSK-gamma and ASK-epsilon. RNA gel blot analyses revealed TaSK5 induction by cold and NaCl treatments and to a lesser extent by drought treatment. TaSK5 functionally complemented the cold- and salt-sensitive phenotypes of a yeast GSK3/shaggy-like kinase mutant, △mck1. Transgenic Arabidopsis plants overexpressing TaSK5 cDNA showed enhanced tolerance to salt and drought stresses. By contrast, the tolerance of the transgenic plants to freezing stress was not altered. Microarray analysis revealed that a number of abiotic stress-inducible genes were constitutively induced in the transgenic Arabidopsis plants, suggesting that TaSK5 may function in a novel signal transduction pathway that appears to be unrelated to DREB1/CBF regulon and may involve crosstalk between abiotic and hormonal signals. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Babu, Vaishnavi; Subathra Devi, C
2015-01-01
Streptokinase (SK) is an extracellular enzyme secreted by various strains of β-hemolytic Streptococci. The main focus of the current study is to evaluate the in vitro thrombolytic activity of purified SK extracted from Streptococcus equinus VIT_VB2 (Accession no. JX406835) isolated from milk sample. The growth rate of S. equinus VIT_VB2 strain was studied with pH and biomass content which has positive significant effect on enzyme yield. A temperature of 10 °C and pH of 6 was found to be optimum for maximum SK activity. The specific activity of the purified SK produced by VIT_VB2 strain was found to be 6,585 IU mg(-1). The molecular mass of the enzyme was determined as 47 kDa by SDS-PAGE. In vitro thrombolytic activity of purified SK was determined using synthetic chromogenic substrate S-2251, the activity of the purified enzyme was found to be 6,330 ± 2.2 IU. The purity of SK was compared with standard SK by HPLC. This is the first report which reveals the SK activity of S. equinus isolated from milk sample.
Sedore, Stanley C.; Byers, Sarah A.; Biglione, Sebastian; Price, Jason P.; Maury, Wendy J.; Price, David H.
2007-01-01
Basal transcription of the HIV LTR is highly repressed and requires Tat to recruit the positive transcription elongation factor, P-TEFb, which functions to promote the transition of RNA polymerase II from abortive to productive elongation. P-TEFb is found in two forms in cells, a free, active form and a large, inactive complex that also contains 7SK RNA and HEXIM1 or HEXIM2. Here we show that HIV infection of cells led to the release of P-TEFb from the large form. Consistent with Tat being the cause of this effect, transfection of a FLAG-tagged Tat in 293T cells caused a dramatic shift of P-TEFb out of the large form to a smaller form containing Tat. In vitro, Tat competed with HEXIM1 for binding to 7SK, blocked the formation of the P-TEFb–HEXIM1–7SK complex, and caused the release P-TEFb from a pre-formed P-TEFb–HEXIM1–7SK complex. These findings indicate that Tat can acquire P-TEFb from the large form. In addition, we found that HEXIM1 binds tightly to the HIV 5′ UTR containing TAR and recruits and inhibits P-TEFb activity. This suggests that in the absence of Tat, HEXIM1 may bind to TAR and repress transcription elongation of the HIV LTR. PMID:17576689
The Role of Education in Preventing Nuclear War.
ERIC Educational Resources Information Center
Markusen, Eric; Harris, John B.
1984-01-01
Examines the role of education in the Holocaust of Nazi Germany, discusses U.S. nuclear weapons policy and factors of psychological resistance that have limited citizen participation in decision making, and explores the potential of education to help prevent nuclear war. (Author/SK)
Faculty Compensation in Continuing Education: Theory versus Practice.
ERIC Educational Resources Information Center
Scott, Joyce A.
1984-01-01
Lawler's Motivation Model and other studies of reward systems are used to develop a policy assessment and development checklist for compensating continuing education faculty. The checklist includes institutional, reward system, and motivation factors that should be considered to encourage faculty participation. (SK)
Pathogenesis of myasthenia gravis: update on disease types, models, and mechanisms.
Phillips, William D; Vincent, Angela
2016-01-01
Myasthenia gravis is an autoimmune disease of the neuromuscular junction (NMJ) caused by antibodies that attack components of the postsynaptic membrane, impair neuromuscular transmission, and lead to weakness and fatigue of skeletal muscle. This can be generalised or localised to certain muscle groups, and involvement of the bulbar and respiratory muscles can be life threatening. The pathogenesis of myasthenia gravis depends upon the target and isotype of the autoantibodies. Most cases are caused by immunoglobulin (Ig)G1 and IgG3 antibodies to the acetylcholine receptor (AChR). They produce complement-mediated damage and increase the rate of AChR turnover, both mechanisms causing loss of AChR from the postsynaptic membrane. The thymus gland is involved in many patients, and there are experimental and genetic approaches to understand the failure of immune tolerance to the AChR. In a proportion of those patients without AChR antibodies, antibodies to muscle-specific kinase (MuSK), or related proteins such as agrin and low-density lipoprotein receptor-related protein 4 (LRP4), are present. MuSK antibodies are predominantly IgG4 and cause disassembly of the neuromuscular junction by disrupting the physiological function of MuSK in synapse maintenance and adaptation. Here we discuss how knowledge of neuromuscular junction structure and function has fed into understanding the mechanisms of AChR and MuSK antibodies. Myasthenia gravis remains a paradigm for autoantibody-mediated conditions and these observations show how much there is still to learn about synaptic function and pathological mechanisms.
The hSK4 (KCNN4) isoform is the Ca2+-activated K+ channel (Gardos channel) in human red blood cells
Hoffman, Joseph F.; Joiner, William; Nehrke, Keith; Potapova, Olga; Foye, Kristen; Wickrema, Amittha
2003-01-01
The question is, does the isoform hSK4, also designated KCNN4, represent the small conductance, Ca2+-activated K+ channel (Gardos channel) in human red blood cells? We have analyzed human reticulocyte RNA by RT-PCR, and, of the four isoforms of SK channels known, only SK4 was found. Northern blot analysis of purified and synchronously growing human erythroid progenitor cells, differentiating from erythroblasts to reticulocytes, again showed only the presence of SK4. Western blot analysis, with an anti-SK4 antibody, showed that human erythroid progenitor cells and, importantly, mature human red blood cell ghost membranes, both expressed the SK4 protein. The Gardos channel is known to turn on, given inside Ca2+, in the presence but not the absence of external \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} \\begin{equation*}{\\mathrm{K}}_{{\\mathrm{o}}}^{+}\\end{equation*}\\end{document} and remains refractory to \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} \\begin{equation*}{\\mathrm{K}}_{{\\mathrm{o}}}^{+}\\end{equation*}\\end{document} added after exposure to inside Ca2+. Heterologously expressed SK4, but not SK3, also shows this behavior. In inside–out patches of red cell membranes, the open probability (Po) of the Gardos channel is markedly reduced when the temperature is raised from 27 to 37°C. Net K+ efflux of intact red cells is also reduced by increasing temperature, as are the Po values of inside–out patches of Chinese hamster ovary cells expressing SK4 (but not SK3). Thus the envelope of evidence indicates that SK4 is the gene that codes for the Gardos channel in human red blood cells. This channel is important pathophysiologically, because it represents the major pathway for cell shrinkage via KCl and water loss that occurs in sickle cell disease. PMID:12773623
DOE Office of Scientific and Technical Information (OSTI.GOV)
Siqueira, M. C.; Maia, R. N. A.; Araujo, R. M. T.
In this article, we investigated structural and thermal properties of an amorphous alloy of the Ga–Se system. The amorphous GaSe{sub 9} alloy was produced by mechanical alloying and it was studied using EXAFS spectroscopy and cumulant expansion method. We also made reverse Monte Carlo simulations using the total structure factor S(K) obtained from x-ray diffraction and the EXAFS χ(k) oscillations on Se and Ga K edges as input data. Several parameters, such as average coordination numbers and interatomic distances, structural and thermal disorders, asymmetry of the partial distribution functions g{sub ij}(r), and Einstein and Debye temperatures, were determined. The g{submore » ij}{sup E}(r) functions were reconstructed from the cumulants C{sub 1}, C{sub 2}, and C{sub 3} obtained from the Einstein model, and they were compared to the g{sub ij}{sup RMC}(r) functions obtained from the simulations. The simulations also furnished the partial bond angle distribution functions Θ{sub ijℓ}(cosθ), which describe the angular distribution of bonds between first neighbors, and give information about the kind of structural units present in the alloy.« less
Imagination in Japanese Educational Experiments.
ERIC Educational Resources Information Center
Dorner, Robert; Kowalski, Ludwik
1992-01-01
In the K. Ikatura method used in Japan, an instructor describes an experiment with a number of possible outcomes. Students record and discuss their predictions; the experiment is performed and the results analyzed. This method creates constructive cognitive conflict and provides structure for imagination. (SK)
ERIC Educational Resources Information Center
Cutchins, M. A.
1982-01-01
Presents programmable calculator solutions to selected problems, including area moments of inertia and principal values, the 2-D principal stress problem, C.G. and pitch inertia computations, 3-D eigenvalue problems, 3 DOF vibrations, and a complex flutter determinant. (SK)
Socio-Political Implications of Participatory Research.
ERIC Educational Resources Information Center
Vio Grossi, Francisco
1981-01-01
Examines trends in participatory research and the need for clarification of it as a process of "disindoctrination" to the status quo and a means of bringing about the structural transformation of society. Issues of popular organization and strategies for increasing viability are discussed. (SK)
Structuring an Internal Evaluation Process.
ERIC Educational Resources Information Center
Gordon, Sheila C.; Heinemann, Harry N.
1980-01-01
The design of an internal program evaluation system requires (1) formulation of program, operational, and institutional objectives; (2) establishment of evaluation criteria; (3) choice of data collection and evaluation techniques; (4) analysis of results; and (5) integration of the system into the mainstream of operations. (SK)
Women Entrepreneurs in a Developing Economy.
ERIC Educational Resources Information Center
Hisrich, Robert D.; Ozturk, Sevgi Ayse
1999-01-01
Survey responses from 54 of 216 Turkish women entrepreneurs revealed many similarities with counterparts in developed nations but differences in reasons and motivation for start-up and problems encountered. Characteristics of developing nations (occupational segregation, wage disparity, social structure) may account for the differences. (SK)
ERIC Educational Resources Information Center
Thomas, Gary
1997-01-01
Argues against the use of theory in educational inquiry, contending that the meaning of theory is unclear; both personal theory and grand theory inhibit creativity and methodology; and less structured problem solving and ad hoc approaches are more likely to result in pluralistic ideas. (SK)
The Women's Movement, Adult Education and Globalization: Women's Agencies in Zimbabwe.
ERIC Educational Resources Information Center
Mpofu, Stanley T.
1996-01-01
Notes that in Zimbabwe, women's agencies pursue practical, strategic, and interagency gender interests consistent with adult education practice. However, they also manifest the globalizing tendencies of pluralism, cultural homogenization, and the coalescence of transnational and domestic processes and structures. (SK)
Integration into What? Reflections on Development Planning for Women.
ERIC Educational Resources Information Center
Boulding, Elise
1980-01-01
Integration of women into the existing international economic and technological order promises only further loss of autonomy and increased marginalization. Women's groups should explore human-centered development which will generate new social structures and new approaches to human productivity and welfare. (SK)
Chen, Mao Xiang; Gorman, Shelby A; Benson, Bill; Singh, Kuljit; Hieble, J Paul; Michel, Martin C; Tate, Simon N; Trezise, Derek J
2004-06-01
The SK/IK family of small and intermediate conductance calcium-activated potassium channels contains four members, SK1, SK2, SK3 and IK1, and is important for the regulation of a variety of neuronal and non-neuronal functions. In this study we have analysed the distribution of these channels in human tissues and their cellular localisation in samples of colon and corpus cavernosum. SK1 mRNA was detected almost exclusively in neuronal tissues. SK2 mRNA distribution was restricted but more widespread than SK1, and was detected in adrenal gland, brain, prostate, bladder, liver and heart. SK3 mRNA was detected in almost every tissue examined. It was highly expressed in brain and in smooth muscle-rich tissues including the clitoris and the corpus cavernosum, and expression in the corpus cavernosum was upregulated up to 5-fold in patients undergoing sex-change operations. IK1 mRNA was present in surface-rich, secretory and inflammatory cell-rich tissues, highest in the trachea, prostate, placenta and salivary glands. In detailed immunohistochemical studies of the colon and the corpus cavernosum, SK1-like immunoreactivity was observed in the enteric neurons. SK3-like immunoreactivity was observed strongly in smooth muscle and vascular endothelium. IK1-like immunoreactivity was mainly observed in inflammatory cells and enteric neurons of the colon, but absent in corpus cavernosum. These distinctive patterns of distribution suggest that these channels are likely to have different biological functions and could be specifically targeted for a number of human diseases, such as irritable bowel syndrome, hypertension and erectile dysfunction.
Filipkowska, Anna; Kowalewska, Grażyna; Pavoni, Bruno
2014-02-01
Sediment samples were collected in the Gulf of Gdańsk, and the Vistula and Szczecin Lagoons-all located in the coastal zone of the Southern Baltic Sea-just after the total ban on using harmful organotins in antifouling paints on ships came into force, to assess their butyltin and phenyltin contamination extent. Altogether, 26 sampling stations were chosen to account for different potential exposure to organotin pollution and environmental conditions: from shallow and well-oxygenated waters, shipping routes and river mouths, to deep and anoxic sites. Additionally, the organic carbon content, pigment content, and grain size of all the sediment samples were determined, and some parameters of the near-bottom water (oxygen content, salinity, temperature) were measured as well. Total concentrations of butyltin compounds ranged between 2 and 182 ng Sn g(-1) d.w., whereas phenyltins were below the detection limit. Sediments from the Gulf of Gdańsk and Vistula Lagoon were found moderately contaminated with tributyltin, whereas those from the Szczecin Lagoon were ranked as highly contaminated. Butyltin degradation indices prove a recent tributyltin input into the sediments adjacent to sites used for dumping for dredged harbor materials and for anchorage in the Gulf of Gdańsk (where two big international ports are located), and into those collected in the Szczecin Lagoon. Essential factors affecting the degradation and distribution of organotins, based on significant correlations between butyltins and environmental variables, were found in the study area.
Anitua, Eduardo; Pelacho, Beatriz; Prado, Roberto; Aguirre, José Javier; Sánchez, Mikel; Padilla, Sabino; Aranguren, Xabier L; Abizanda, Gloria; Collantes, María; Hernandez, Milagros; Perez-Ruiz, Ana; Peñuelas, Ivan; Orive, Gorka; Prosper, Felipe
2015-03-28
PRGF is a platelet concentrate within a plasma suspension that forms an in situ-generated fibrin-matrix delivery system, releasing multiple growth factors and other bioactive molecules that play key roles in tissue regeneration. This study was aimed at exploring the angiogenic and myogenic effects of PRGF on in vitro endothelial cells (HUVEC) and skeletal myoblasts (hSkMb) as well as on in vivo mouse subcutaneously implanted matrigel and on limb muscles after a severe ischemia. Human PRGF was prepared and characterized. Both proliferative and anti-apoptotic responses to PRGF were assessed in vitro in HUVEC and hSkMb. In vivo murine matrigel plug assay was conducted to determine the angiogenic capacity of PRGF, whereas in vivo ischemic hind limb model was carried out to demonstrate PRGF-driven vascular and myogenic regeneration. Primary HUVEC and hSkMb incubated with PRGF showed a dose dependent proliferative and anti-apoptotic effect and the PRGF matrigel plugs triggered an early and significant sustained angiogenesis compared with the control group. Moreover, mice treated with PRGF intramuscular infiltrations displayed a substantial reperfusion enhancement at day 28 associated with a fibrotic tissue reduction. These findings suggest that PRGF-induced angiogenesis is functionally effective at expanding the perfusion capacity of the new vasculature and attenuating the endogenous tissue fibrosis after a severe-induced skeletal muscle ischemia. Copyright © 2015 Elsevier B.V. All rights reserved.
Samuilov, V D; Kiselevsky, D B
2015-04-01
Plastoquinone bound with decyltriphenylphosphonium cation (SkQ1) penetrating through the membrane in nanomolar concentrations inhibited H2O2 generation in cells of epidermis of pea seedling leaves that was detected by the fluorescence of 2',7'-dichlorofluorescein. Photosynthetic electron transfer in chloroplasts isolated from pea leaves is suppressed by SkQ1 at micromolar concentrations: the electron transfer in chloroplasts under the action of photosystem II or I (with silicomolybdate or methyl viologen as electron acceptors, respectively) is more sensitive to SkQ1 than under the action of photosystem II + I (with ferricyanide or p-benzoquinone as electron acceptors). SkQ1 reduced by borohydride is oxidized by ferricyanide, p-benzoquinone, and, to a lesser extent, by silicomolybdate, but not by methyl viologen. SkQ1 is not effective as an electron acceptor supporting O2 evolution from water in illuminated chloroplasts. The data on suppression of photosynthetic O2 evolution or consumption show that SkQ1, similarly to phenazine methosulfate, causes conversion of the chloroplast redox-chain from non-cyclic electron transfer mode to the cyclic mode without O2 evolution. Oxidation of NADH or succinate in mitochondria isolated from pea roots is stimulated by SkQ1.
Bridging the Gap between School and Work.
ERIC Educational Resources Information Center
Filipczak, Bob
1993-01-01
Boston's Project ProTech is a private industry council youth apprenticeship program that places high school students in hospitals to explore and train for health care occupations. Success factors include employer participation in student selection and a first-year orientation and job rotation scheme. (SK)
The Key Pieces of the Career Survival and Success Puzzle.
ERIC Educational Resources Information Center
Simonetti, Jack L.
1999-01-01
Analysis of career-success factors identified by 5,000 managers yielded 10 key pieces: excellent performance record, communication skills, interpersonal skills, personality, skill currency, significant work experiences, power, ability to withstand pressure, ability to make difficult decisions, and having a mentor. (SK)
The blue globular pattern in dermoscopy.
Roberti, V; Devirgiliis, V; Curzio, M; Gobbi, S; Coppola, R; Calvieri, S; Panasiti, V
2013-01-01
Seborrheic keratosis (SK) is a frequent benign epithelial skin tumor. Generally its diagnosis is clinical, however SK can sometimes clinically simulate a melanocytic lesion; therefore we need dermoscopy to reach a correct diagnosis. Milia-like cysts and comedo-like openings are the common dermoscopic features of SK, but it is not a rare finding that SK can display one or more dermoscopic patterns suggestive of a melanocytic origin. We describe a case series of SKs with a blue globular pattern simulating a melanocytic lesion. We retrospectively evaluated 224 SKs seen during 2011 at the Dermatoscopy Unit of the Department of Dermatology, University of Rome 'Sapienza'. Five SKs showed a blue globular pattern, without the SK main features generally seen in dermoscopy; globules were multiple, round or oval, well-demarcated, small and medium-sized, blue-colored and equally distributed within the lesion. Histopathologic examination was consistent with acanthotic SK. Identification of the blue globular pattern can be helpful for the dermoscopic diagnosis of SK, especially when its common dermoscopic features are absent. Copyright © 2013 S. Karger AG, Basel.
The Blue Ribbon: An American Way of Life.
ERIC Educational Resources Information Center
Weber, Joseph A.; McCullers, John C.
1986-01-01
The notion that blue ribbons serve to increase the motivation and performance of 4-H youth may not always be true. Studies of the effect of such incentives give cause for reevaluation of the present reward structure in light of current 4-H philosophy. (SK)
Reawakening Your Passion for Work.
ERIC Educational Resources Information Center
Boyatzis, Richard; McKee, Annie; Goleman, Daniel
2002-01-01
Five strategies can help people find meaning in work and renew their passion: (1) taking a short- or long-term break; (2) finding a development program; (3) creating reflective structures (spiritual, meditative, or other); (4) working with a coach; and (5) seeking new meaning in familiar territory. (SK)
Controlled Release Applications of Organometals.
ERIC Educational Resources Information Center
Thayer, John S.
1981-01-01
Reviews two classes of controlled release organometals: (1) distributional, to distribute bioactive materials to control a certain target organism; and (2) protective, to protect surface or interior of some structure from attach by organisms. Specific examples are given including a discussion of controlled release for schistosomiasis. (SK)
Responsibility-Centered Management: A 10-Year Nursing Assessment.
ERIC Educational Resources Information Center
McBride, Angela Barron; Neiman, Sandra; Johnson, James
2000-01-01
Describes the implementation of responsibility-centered management, a decentralized model giving deans responsibility for expanding and using resources, at Indiana University's nursing school. Discusses how it led to creation of an information-rich environment, strategic decision making, and a performance-based reward structure. (SK)
Branching fraction measurement of J / ψ → K S K L and search for J / ψ → K S K S
Ablikim, M.; Achasov, M. N.; Ahmed, S.; ...
2017-12-04
Using a sample of 1.31×10 9J/ψ events collected with the BESIII detector at the BEPCII collider, we study the decays of J/ψ→ K SK L and K SK S. The branching fraction of J/ψ→ K SK L is determined to be B(J/ψ→ K SK L) = (1:93 0:01 (stat:) 0:05 (syst:))×10 -4, which signi cantly improves on previous measurements. No clear signal is observed for the J/ψ→ K SK S process, and the upper limit at the 95% con dence level for its branching fraction is determined to be B(J= ! K SK S) < 1:4×10 -8, which improves onmore » the previous searches by 2 orders in magnitude and reaches the order of the Einstein-Podolsky-Rosen expectation.« less
Branching fraction measurement of J / ψ → K S K L and search for J / ψ → K S K S
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ablikim, M.; Achasov, M. N.; Ahmed, S.
Using a sample of 1.31×10 9J/ψ events collected with the BESIII detector at the BEPCII collider, we study the decays of J/ψ→ K SK L and K SK S. The branching fraction of J/ψ→ K SK L is determined to be B(J/ψ→ K SK L) = (1:93 0:01 (stat:) 0:05 (syst:))×10 -4, which signi cantly improves on previous measurements. No clear signal is observed for the J/ψ→ K SK S process, and the upper limit at the 95% con dence level for its branching fraction is determined to be B(J= ! K SK S) < 1:4×10 -8, which improves onmore » the previous searches by 2 orders in magnitude and reaches the order of the Einstein-Podolsky-Rosen expectation.« less
Otsuka, M; Shinozuka, K; Hirata, G; Kunitomo, M
1996-02-01
Effects of the mixture (SK-204) consisting of dried shiitake mushroom (Lentinus edodes) treated with wet-heating and fructo-oligosaccharides (7:3) on the experimental models of pulmonary thrombosis induced by lactic acidosis in rats were evaluated. Chronic oral administration (10 weeks) of SK-204 significantly prevented the thrombus formation on this thrombosis model. However, decreases in the numbers of platelet and fibrinogen level by lactate were not changed by SK-204. These results suggest that SK-204 have an anti-thrombotic action, which is due to neither the inhibition of platelet aggregation nor coagulation, but probably due to the promotion of fibrinolysis and thrombolysis.
Determinants of Underemployment of Young Adults: A Multi-Country Study.
ERIC Educational Resources Information Center
Ruiz-Quintanilla, S. Antonio; Claes, Rita
1996-01-01
Data from the international Work Socialization of Youth project (1988-90) were analyzed for office technology workers and machine operators in six European countries. Organizational and societal factors had greater influence on part-time/temporary employment than did job search strategies, gender, or age. (SK)
Factors that Affect College of Business Student Opinion of Teaching and Learning.
ERIC Educational Resources Information Center
Whitworth, James E.; Price, Barbara A.; Randall, Cindy H.
2002-01-01
Analysis of 12,153 student evaluations of business teachers indicated that ratings differed significantly according to faculty gender, course type, and level (graduate/undergraduate). Female faculty received higher ratings. Graduate students tended to give higher ratings than undergraduates did. (Contains 16 references.) (SK)
"Voices" and "Voces": Cultural and Linguistic Dimensions of Giftedness.
ERIC Educational Resources Information Center
Clark, Ellen Riojas; Gonzalez, Virginia
1998-01-01
Assessments of a 6-year-old Spanish monolingual and 5-year-old bilingual children included a home-language survey, parents' and teachers' ratings, cartoon conservation scales, and standardized tests. Nonverbal cognitive development was shown to influence language acquisition. Cultural and linguistic factors affected children differently. (SK)
An efficient synthesis of SK-658 and its analogs as potent histone deacetylase inhibitors.
Shahidul Islam, Md; Nurul Islam, Md; Ashraful Hoque, Md; Nishino, Norikazu; Kato, Tamaki; Kim, Hyun-Jung; Ito, Akihiro; Yoshida, Minoru
2015-04-01
SK-658 is a potent histone deacetylase (HDAC) inhibitor that showed higher activity than SAHA due to the presence of extended hydrophobic group. We designed and synthesized thioester and SS-hybrid bearing SK-658 analogs as HDAC inhibitors. All the compounds were active in nano molar range and showed higher inhibitory activity than SAHA and SK-658. Among these, disulfide compounds showed the highest activity. Copyright © 2015 Elsevier Inc. All rights reserved.
Yamada, Chisa; Teener, James W; Davenport, Robertson D; Cooling, Laura
2015-10-01
Anti-muscle specific kinase antibody positive myasthenia gravis (MuSK MG) is often characterized by a relatively severe and progressive course, refractoriness to standard myasthenia gravis (MG) medications, and an increased risk of myasthenic crisis. We report here successful management of three MuSK MG patients using maintenance therapeutic plasma exchange (TPE) treatment for up to 4.5 years. The study was a 5-year retrospective review of all MG patients treated with TPE between 2008 and 2013 at University of Michigan. Inclusion criteria of MuSK MG were positive for anti-MuSK antibodies and a diagnosis of MuSK MG by staff neurologists. Patient data included age, gender, diagnostic testing results, medications, and the dates and response to TPE treatments. A total of 153 MG patients underwent at least one course of TPE between 2008 and 2013. A total of 12 patients (7.8%) were positive for anti-MuSK antibodies. Patients were predominantly female (83.3%) and a median age of onset was 46-years old. Three MuSK MG patients were successfully managed with maintenance TPE. Maintenance TPE may be an effective option for MuSK MG patients. The key of successful maintenance treatment at our institution has been to tailor the TPE frequency for each individual, and to modify the treatment interval in conjunction with medical management. © 2014 Wiley Periodicals, Inc.
Lavieu, Grégory; Scarlatti, Francesca; Sala, Giusy; Carpentier, Stéphane; Levade, Thierry; Ghidoni, Riccardo; Botti, Joëlle; Codogno, Patrice
2006-03-31
The sphingolipid ceramide induces macroautophagy (here called autophagy) and cell death with autophagic features in cancer cells. Here we show that overexpression of sphingosine kinase 1 (SK1), an enzyme responsible for the production of sphingosine 1-phosphate (S1P), in MCF-7 cells stimulates autophagy by increasing the formation of LC3-positive autophagosomes and the rate of proteolysis sensitive to the autophagy inhibitor 3-methyladenine. Autophagy was blocked in the presence of dimethylsphingosine, an inhibitor of SK activity, and in cells expressing a catalytically inactive form of SK1. In SK1(wt)-overexpressing cells, however, autophagy was not sensitive to fumonisin B1, an inhibitor of ceramide synthase. In contrast to ceramide-induced autophagy, SK1(S1P)-induced autophagy is characterized by (i) the inhibition of mammalian target of rapamycin signaling independently of the Akt/protein kinase B signaling arm and (ii) the lack of robust accumulation of the autophagy protein Beclin 1. In addition, nutrient starvation induced both the stimulation of autophagy and SK activity. Knocking down the expression of the autophagy protein Atg7 or that of SK1 by siRNA abolished starvation-induced autophagy and increased cell death with apoptotic hallmarks. In conclusion, these results show that SK1(S1P)-induced autophagy protects cells from death with apoptotic features during nutrient starvation.
Oliveira, Mauro S.; Skinner, Frank; Arshadmansab, Massoud F.; Garcia, Ileana; Mello, Carlos F.; Knaus, Hans-Günther; Ermolinsky, Boris S.; Pacheco Otalora, Luis F.; Garrido-Sanabria, Emilio R.
2010-01-01
Small conductance calcium (Ca2+) activated SK channels are critical regulators of neuronal excitability in hippocampus. Accordingly, these channels are thought to play a key role in controlling neuronal activity in acute models of epilepsy. In this study, we investigate the expression and function of SK channels in the pilocarpine model of mesial temporal lobe epilepsy. For this purpose, protein expression was assessed using western blotting assays and gene expression was analyzed using TaqMan-based probes and the quantitative real-time polymerase chain reaction (qPCR) comparative method delta-delta cycle threshold (ΔΔCT) in samples extracted from control and epileptic rats. In addition, the effect of SK channel antagonist UCL1684 and agonist NS309 on CA1 evoked population spikes was studied in hippocampal slices. Western blotting analysis showed a significant reduction in the expression of SK1 and SK2 channels at 10 days following status epilepticus (SE), but levels recovered at 1 month and at more than 2 months after SE. In contrast, a significant down-regulation of SK3 channels was detected after 10 days of SE. Analysis of gene expression by qPCR revealed a significant reduction of transcripts for SK2 (Kcnn1) and SK3 (Kcnn3) channels as early as 10 days following pilocarpine-induced SE and during the chronic phase of the pilocarpine model. Moreover, bath application of UCL1684 (100 nM for 15 min) induced a significant increase of the population spike amplitude and number of spikes in the hippocampal CA1 area of slices obtained control and chronic epileptic rats. This effect was obliterated by co-administration of UCL1684 with SK channel agonist NS309 (1 μM). Application of NS309 failed to modify population spikes in the CA1 area of slices taken from control and epileptic rats. These data indicate an abnormal expression of SK channels and a possible dysfunction of these channels in experimental MTLE. PMID:20553876
Pharmacologic study of C-terminal fragments of frog skin calcitonin gene-related peptide.
Ladram, Ali; Besné, Isabelle; Breton, Lionel; de Lacharrière, Olivier; Nicolas, Pierre; Amiche, Mohamed
2008-07-01
The calcitonin gene-related peptide from the skin of the frog Phyllomedusa bicolor (pbCGRP) is a 37-residue neuropeptide that differs from human alpha CGRP (halphaCGRP) at 16 positions. The affinities of the C-terminal fragments of pbCGRP and halphaCGRP were evaluated in SK-N-MC cells: pbCGRP(8-37) (K(i)=0.2nM) and pbCGRP(27-37) (K(i)=95nM) were, respectively, 3 times and 20 times more potent than the human fragments halphaCGRP(8-37) and halphaCGRP(27-37). Their antagonistic potencies were measured in SK-N-MC and Col 29 cells, and the rat vas deferens. pbCGRP(8-37) inhibited the halphaCGRP-stimulated production of cAMP by SK-N-MC and Col 29 cells 3 to 4 times more strongly than halphaCGRP(8-37). Thus pbCGRP(8-37) is the most potent CGRP-1 competitive antagonist of all the natural sequences reported to date. pbCGRP(27-37) was also as potent as [D(31), A(34), F(35)] halphaCGRP(27-37), a prototypic antagonist analog derived from structure-activity relationship studies of halphaCGRP(8-37).
Polak, Agnieszka; Rejdak, Robert; Czepita, Damian; Rekas, Marek; Wróbel, Andrzej
2015-01-01
Changes in the economy in Poland in the years 1864-1914 generated changes in the structure of society. A new social stratum, the intelligentsia, was formed from the educated children of rich landowners. To meet social needs Polish universities in Cracow and Lviv opened new departments of medicine. The article presents fragments of the biographies of 4 Poles: Kazimierz Noiszewski, Józef Piłsudski, Bolesław Wieniawa-Długoszowski and Stanislaw Sławoj Składkowski to illustrate how their study of medicine affected their further activity as patriots and politicians. Kazimierz Noiszewski was an emigrant who lived and worked as an ophthalmologist in Russia. He tried to support the Polish community and Polish medical knowledge. For Józef Pilsudski and Stanisław Sławoj Składkowski medical studies gave freedom of thought and the opportunity to meet other patriots. Boleslaw Wieniawa-Długoszowski was a man of many interests, and after graduating from a medical university in Lviv, and a short stay in Paris, he became engaged in military service for his country.
Partnership for Self-Reliant Change: Institute for Integrated Rural Development.
ERIC Educational Resources Information Center
Dancey, John
1994-01-01
The Institute for Integrated Rural Development in the Maharashtra State of India seeks to break the cycle of poverty through sustainable rural development. It works closely with rural women on health and nutrition education and in other community partnerships based on horizontal structures. (SK)
Why You Are in Trouble If You Think Marketing Is Just Sales.
ERIC Educational Resources Information Center
Cook, Kenneth J.
1997-01-01
Distinguishes between marketing (analysis and strategies with which to position a business) and sales (implementation of marketing ideas). Identifies pitfalls of equating the two, such as sales plans without a marketing foundation and failure to structure sales tactics around customer needs. (SK)
The Direction of Web-based Training: A Practitioner's View.
ERIC Educational Resources Information Center
Kilby, Tim
2001-01-01
Web-based training has had achievements and disappointments as online learning has matured. Best practices include user-centered design, knowledge object structures, usability engineering, and formal evaluation. Knowledge management, peer-to-peer learning, and personal learning appliances will continue to alter the online learning landscape. (SK)
Female-Male Earnings Differentials and Occupational Structure.
ERIC Educational Resources Information Center
Terrell, Katherine
1992-01-01
A review of econometric literature on female-male wage differences and asymmetrical distribution in occupations shows that differences in returns to human capital (i.e., discrimination) explains far more of the wage gap than differences in education and experience. Crowding of women into few occupations depresses wages. (SK)
Rank Regressions, Wage Distributions, and the Gender Gap.
ERIC Educational Resources Information Center
Fortin, Nicole M.; Lemieux, Thomas
1998-01-01
Current Population Survey data from 1979 and 1991 were used to decompose changes in the gender wage gap into three components: skill distribution, wage structure, and improvements in women's position. Relative wage gains by women may have been a source of increasing wage inequality among men. (SK)
NASA Astrophysics Data System (ADS)
Kung, Mei-Lang; Hsieh, Shu-Ling; Wu, Chih-Chung; Chu, Tian-Huei; Lin, Yu-Chun; Yeh, Bi-Wen; Hsieh, Shuchen
2015-01-01
Copper oxide nanoparticles (CuO NPs) are known to exhibit toxic effects on a variety of cell types and organs. To determine the oxidative impact of CuO NPs on hepatocellular carcinoma (HCC) cells, well-differentiated (HepG2) and poorly differentiated (SK-Hep-1) cells were exposed to CuO NPs. Cell viability assay showed that the median inhibition concentration (IC50) for SK-Hep-1 and HepG2 cells was 25 μg ml-1 and 85 μg ml-1, respectively. Cellular fluorescence intensity using DCFH-DA staining analysis revealed significant intracellular reactive oxygen species (ROS) generation of up to 242% in SK-Hep-1 cells, compared with 86% in HepG2 cells. HPLC analysis demonstrated that a CuO NP treatment caused cellular GSH depletion of 58% and a GSH/GSSG ratio decrease to ~0.1 in SK-Hep-1 cells. The oxidative stress caused by enhanced superoxide anion production was observed in both HepG2 (146%) and SK-Hep-1 (192%) cells. The Griess assay verified that CuO NPs induced NO production (170%) in SK-Hep-1 cells. Comet assay and western blot further demonstrated that CuO NPs induced severe DNA strand breakage (70%) in SK-Hep-1 cells and caused DNA damage via increased γ-H2AX levels. These results suggest that well-differentiated HepG2 cells possess a robust antioxidant defense system against CuO NP-induced ROS stress and exhibit more tolerance to oxidative stress. Conversely, poorly differentiated SK-Hep-1 cells exhibited a deregulated antioxidant defense system that allowed accumulation of CuO NP-induced ROS and resulted in severe cytotoxicity.Copper oxide nanoparticles (CuO NPs) are known to exhibit toxic effects on a variety of cell types and organs. To determine the oxidative impact of CuO NPs on hepatocellular carcinoma (HCC) cells, well-differentiated (HepG2) and poorly differentiated (SK-Hep-1) cells were exposed to CuO NPs. Cell viability assay showed that the median inhibition concentration (IC50) for SK-Hep-1 and HepG2 cells was 25 μg ml-1 and 85 μg ml-1, respectively. Cellular fluorescence intensity using DCFH-DA staining analysis revealed significant intracellular reactive oxygen species (ROS) generation of up to 242% in SK-Hep-1 cells, compared with 86% in HepG2 cells. HPLC analysis demonstrated that a CuO NP treatment caused cellular GSH depletion of 58% and a GSH/GSSG ratio decrease to ~0.1 in SK-Hep-1 cells. The oxidative stress caused by enhanced superoxide anion production was observed in both HepG2 (146%) and SK-Hep-1 (192%) cells. The Griess assay verified that CuO NPs induced NO production (170%) in SK-Hep-1 cells. Comet assay and western blot further demonstrated that CuO NPs induced severe DNA strand breakage (70%) in SK-Hep-1 cells and caused DNA damage via increased γ-H2AX levels. These results suggest that well-differentiated HepG2 cells possess a robust antioxidant defense system against CuO NP-induced ROS stress and exhibit more tolerance to oxidative stress. Conversely, poorly differentiated SK-Hep-1 cells exhibited a deregulated antioxidant defense system that allowed accumulation of CuO NP-induced ROS and resulted in severe cytotoxicity. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr05843g
Harvey-Leeson, Sarah; Karakochuk, Crystal D.; Hawes, Meaghan; Tugirimana, Pierrot L.; Bahizire, Esto; Akilimali, Pierre Z.; Michaux, Kristina D.; Lynd, Larry D.; Whitfield, Kyly C.; Moursi, Mourad; Boy, Erick; Foley, Jennifer; McLean, Judy; Houghton, Lisa A.; Gibson, Rosalind S.; Green, Tim J.
2016-01-01
Little is known about the micronutrient status of women and children in the Democratic Republic of the Congo, which is critical for the design of effective nutrition interventions. We recruited 744 mother-child pairs from South Kivu (SK) and Kongo Central (KC). We determined hemoglobin (Hb), serum zinc, vitamin B12, folate, ferritin, soluble transferrin receptor (sTfR), retinol binding protein (RBP), C-reactive protein, and α-1 acid glycoprotein concentrations. Anemia prevalence was determined using Hb adjusted for altitude alone and Hb adjusted for both altitude and ethnicity. Anemia prevalence was lower after Hb adjustment for altitude and ethnicity, compared to only altitude, among women (6% vs. 17% in SK; 10% vs. 32% in KC), children 6–23 months (26% vs. 59% in SK; 25% vs. 42% in KC), and children 24–59 months (14% vs. 35% in SK; 23% vs. 44% in KC), respectively. Iron deficiency was seemingly higher with sTfR as compared to inflammation-adjusted ferritin among women (18% vs. 4% in SK; 21% vs. 5% in KC), children 6–23 months (51% vs. 14% in SK; 74% vs. 10% in KC), and children 24–59 months (23% vs. 4% in SK; 58% vs. 1% in KC). Regardless of indicator, iron deficiency anemia (IDA) never exceeded 3% in women. In children, IDA reached almost 20% when sTfR was used but was only 10% with ferritin. Folate, B12, and vitamin A (RBP) deficiencies were all very low (<5%); RBP was 10% in children. The prevalence of anemia was unexpectedly low. Inflammation-adjusted zinc deficiency was high among women (52% in SK; 58% in KC), children 6–23 months (23% in SK; 20% in KC), and children 24–59 months (25% in SK; 27% in KC). The rate of biochemical zinc deficiency among Congolese women and children requires attention. PMID:26901219
Harvey-Leeson, Sarah; Karakochuk, Crystal D; Hawes, Meaghan; Tugirimana, Pierrot L; Bahizire, Esto; Akilimali, Pierre Z; Michaux, Kristina D; Lynd, Larry D; Whitfield, Kyly C; Moursi, Mourad; Boy, Erick; Foley, Jennifer; McLean, Judy; Houghton, Lisa A; Gibson, Rosalind S; Green, Tim J
2016-02-17
Little is known about the micronutrient status of women and children in the Democratic Republic of the Congo, which is critical for the design of effective nutrition interventions. We recruited 744 mother-child pairs from South Kivu (SK) and Kongo Central (KC). We determined hemoglobin (Hb), serum zinc, vitamin B12, folate, ferritin, soluble transferrin receptor (sTfR), retinol binding protein (RBP), C-reactive protein, and α-1 acid glycoprotein concentrations. Anemia prevalence was determined using Hb adjusted for altitude alone and Hb adjusted for both altitude and ethnicity. Anemia prevalence was lower after Hb adjustment for altitude and ethnicity, compared to only altitude, among women (6% vs. 17% in SK; 10% vs. 32% in KC), children 6-23 months (26% vs. 59% in SK; 25% vs. 42% in KC), and children 24-59 months (14% vs. 35% in SK; 23% vs. 44% in KC), respectively. Iron deficiency was seemingly higher with sTfR as compared to inflammation-adjusted ferritin among women (18% vs. 4% in SK; 21% vs. 5% in KC), children 6-23 months (51% vs. 14% in SK; 74% vs. 10% in KC), and children 24-59 months (23% vs. 4% in SK; 58% vs. 1% in KC). Regardless of indicator, iron deficiency anemia (IDA) never exceeded 3% in women. In children, IDA reached almost 20% when sTfR was used but was only 10% with ferritin. Folate, B12, and vitamin A (RBP) deficiencies were all very low (<5%); RBP was 10% in children. The prevalence of anemia was unexpectedly low. Inflammation-adjusted zinc deficiency was high among women (52% in SK; 58% in KC), children 6-23 months (23% in SK; 20% in KC), and children 24-59 months (25% in SK; 27% in KC). The rate of biochemical zinc deficiency among Congolese women and children requires attention.
Mourot, Laurent; Fabre, Nicolas; Andersson, Erik; Willis, Sarah J; Hébert-Losier, Kim; Holmberg, Hans-Christer
2014-08-01
The aim of this study was to assess potential changes in the performance and cardiorespiratory responses of elite cross-country skiers following transition from the classic (CL) to the skating (SK) technique during a simulated skiathlon. Eight elite male skiers performed two 6 km (2 × 3 km) roller-skiing time trials on a treadmill at racing speed: one starting with the classic and switching to the skating technique (CL1-SK2) and another employing the skating technique throughout (SK1-SK2), with continuous monitoring of gas exchanges, heart rates, and kinematics (video). The overall performance times in the CL1-SK2 (21:12 ± 1:24) and SK1-SK2 (20:48 ± 2:00) trials were similar, and during the second section of each performance times and overall cardiopulmonary responses were also comparable. However, in comparison with SK1-SK2, the CL1-SK2 trial involved significantly higher increases in minute ventilation (V̇E, 89.8 ± 26.8 vs. 106.8 ± 17.6 L·min(-1)) and oxygen uptake (V̇O2; 3.1 ± 0.8 vs 3.5 ± 0.5 L·min(-1)) 2 min after the transition as well as longer time constants for V̇E, V̇O2, and heart rate during the first 3 min after the transition. This higher cardiopulmonary exertion was associated with ∼3% faster cycle rates. In conclusion, overall performance during the 2 time trials did not differ. The similar performance times during the second sections were achieved with comparable mean cardiopulmonary responses. However, the observation that during the initial 3-min post-transition following classic skiing cardiopulmonary responses and cycle rates were slightly higher supports the conclusion that an initial section of classic skiing exerts an impact on performance during a subsequent section of skate skiing.
Aoki, Ken; Zhao, Kun; Yamazaki, Fumio; Sone, Ryoko; Alvarez, Guy E; Kosiba, Wojciech A; Johnson, John M
2008-03-01
Humans and other diurnal species experience a fall in internal temperature (T(int)) at night, accompanied by increased melatonin and altered thermoregulatory control of skin blood flow (SkBF). Also, exogenous melatonin induces a fall in T(int), an increase in distal skin temperatures and altered control of the cutaneous active vasodilator system, suggesting an effect of melatonin on the control of SkBF. To test whether exogenous melatonin also affects the more tonically active vasoconstrictor system in glabrous and nonglabrous skin during cooling, healthy males (n = 9) underwent afternoon sessions of whole body skin temperature (T(sk)) cooling (water-perfused suits) after oral melatonin (Mel; 3 mg) or placebo (Cont). Cutaneous vascular conductance (CVC) was calculated from SkBF (laser Doppler flowmetry) and non-invasive blood pressure. Baseline T(int) was lower in Mel than in Cont (P < 0.01). During progressive reduction of T(sk) from 35 degrees C to 32 degrees C, forearm CVC was first significantly reduced at T(sk) of 34.33 +/- 0.01 degrees C (P < 0.05) in Cont. In contrast, CVC in Mel was not significantly reduced until T(sk) reached 33.33 +/- 0.01 degrees C (P < 0.01). The decrease in forearm CVC in Mel was significantly less than in Cont at T(sk) of 32.66 +/- 0.01 degrees C and lower (P < 0.05). In Mel, palmar CVC was significantly higher than in Cont above T(sk) of 33.33 +/- 0.01 degrees C, but not below. Thus exogenous melatonin blunts reflex vasoconstriction in nonglabrous skin and shifts vasoconstrictor system control to lower T(int). It provokes vasodilation in glabrous skin but does not suppress the sensitivity to falling T(sk). These findings suggest that by affecting the vasoconstrictor system, melatonin has a causal role in the nocturnal changes in body temperature and its control.
Yamaguchi, Haruka; Tsuchimochi, Makoto; Hayama, Kazuhide; Kawase, Tomoyuki; Tsubokawa, Norio
2016-01-01
We sought to develop dual-modality imaging probes using functionalized silica nanoparticles to target human epidermal growth factor receptor 2 (HER2)-overexpressing breast cancer cells and achieve efficient target imaging of HER2-expressing tumors. Polyamidoamine-based functionalized silica nanoparticles (PCSNs) for multimodal imaging were synthesized with near-infrared (NIR) fluorescence (indocyanine green (ICG)) and technetium-99m (99mTc) radioactivity. Anti-HER2 antibodies were bound to the labeled PCSNs. These dual-imaging probes were tested to image HER2-overexpressing breast carcinoma cells. In vivo imaging was also examined in breast tumor xenograft models in mice. SK-BR3 (HER2 positive) cells were imaged with stronger NIR fluorescent signals than that in MDA-MB231 (HER2 negative) cells. The increased radioactivity of the SK-BR3 cells was also confirmed by phosphor imaging. NIR images showed strong fluorescent signals in the SK-BR3 tumor model compared to muscle tissues and the MDA-MB231 tumor model. Automatic well counting results showed increased radioactivity in the SK-BR3 xenograft tumors. We developed functionalized silica nanoparticles loaded with 99mTc and ICG for the targeting and imaging of HER2-expressing cells. The dual-imaging probes efficiently imaged HER2-overexpressing cells. Although further studies are needed to produce efficient isotope labeling, the results suggest that the multifunctional silica nanoparticles are a promising vehicle for imaging specific components of the cell membrane in a dual-modality manner. PMID:27399687
Yamaguchi, Haruka; Tsuchimochi, Makoto; Hayama, Kazuhide; Kawase, Tomoyuki; Tsubokawa, Norio
2016-07-07
We sought to develop dual-modality imaging probes using functionalized silica nanoparticles to target human epidermal growth factor receptor 2 (HER2)-overexpressing breast cancer cells and achieve efficient target imaging of HER2-expressing tumors. Polyamidoamine-based functionalized silica nanoparticles (PCSNs) for multimodal imaging were synthesized with near-infrared (NIR) fluorescence (indocyanine green (ICG)) and technetium-99m ((99m)Tc) radioactivity. Anti-HER2 antibodies were bound to the labeled PCSNs. These dual-imaging probes were tested to image HER2-overexpressing breast carcinoma cells. In vivo imaging was also examined in breast tumor xenograft models in mice. SK-BR3 (HER2 positive) cells were imaged with stronger NIR fluorescent signals than that in MDA-MB231 (HER2 negative) cells. The increased radioactivity of the SK-BR3 cells was also confirmed by phosphor imaging. NIR images showed strong fluorescent signals in the SK-BR3 tumor model compared to muscle tissues and the MDA-MB231 tumor model. Automatic well counting results showed increased radioactivity in the SK-BR3 xenograft tumors. We developed functionalized silica nanoparticles loaded with (99m)Tc and ICG for the targeting and imaging of HER2-expressing cells. The dual-imaging probes efficiently imaged HER2-overexpressing cells. Although further studies are needed to produce efficient isotope labeling, the results suggest that the multifunctional silica nanoparticles are a promising vehicle for imaging specific components of the cell membrane in a dual-modality manner.
Kemp, John P; Medina-Gomez, Carolina; Estrada, Karol; St Pourcain, Beate; Heppe, Denise H M; Warrington, Nicole M; Oei, Ling; Ring, Susan M; Kruithof, Claudia J; Timpson, Nicholas J; Wolber, Lisa E; Reppe, Sjur; Gautvik, Kaare; Grundberg, Elin; Ge, Bing; van der Eerden, Bram; van de Peppel, Jeroen; Hibbs, Matthew A; Ackert-Bicknell, Cheryl L; Choi, Kwangbom; Koller, Daniel L; Econs, Michael J; Williams, Frances M K; Foroud, Tatiana; Zillikens, M Carola; Ohlsson, Claes; Hofman, Albert; Uitterlinden, André G; Davey Smith, George; Jaddoe, Vincent W V; Tobias, Jonathan H; Rivadeneira, Fernando; Evans, David M
2014-06-01
Heritability of bone mineral density (BMD) varies across skeletal sites, reflecting different relative contributions of genetic and environmental influences. To quantify the degree to which common genetic variants tag and environmental factors influence BMD, at different sites, we estimated the genetic (rg) and residual (re) correlations between BMD measured at the upper limbs (UL-BMD), lower limbs (LL-BMD) and skull (SK-BMD), using total-body DXA scans of ∼ 4,890 participants recruited by the Avon Longitudinal Study of Parents and their Children (ALSPAC). Point estimates of rg indicated that appendicular sites have a greater proportion of shared genetic architecture (LL-/UL-BMD rg = 0.78) between them, than with the skull (UL-/SK-BMD rg = 0.58 and LL-/SK-BMD rg = 0.43). Likewise, the residual correlation between BMD at appendicular sites (r(e) = 0.55) was higher than the residual correlation between SK-BMD and BMD at appendicular sites (r(e) = 0.20-0.24). To explore the basis for the observed differences in rg and re, genome-wide association meta-analyses were performed (n ∼ 9,395), combining data from ALSPAC and the Generation R Study identifying 15 independent signals from 13 loci associated at genome-wide significant level across different skeletal regions. Results suggested that previously identified BMD-associated variants may exert site-specific effects (i.e. differ in the strength of their association and magnitude of effect across different skeletal sites). In particular, variants at CPED1 exerted a larger influence on SK-BMD and UL-BMD when compared to LL-BMD (P = 2.01 × 10(-37)), whilst variants at WNT16 influenced UL-BMD to a greater degree when compared to SK- and LL-BMD (P = 2.31 × 10(-14)). In addition, we report a novel association between RIN3 (previously associated with Paget's disease) and LL-BMD (rs754388: β = 0.13, SE = 0.02, P = 1.4 × 10(-10)). Our results suggest that BMD at different skeletal sites is under a mixture of shared and specific genetic and environmental influences. Allowing for these differences by performing genome-wide association at different skeletal sites may help uncover new genetic influences on BMD.
Estrada, Karol; St Pourcain, Beate; Heppe, Denise H. M.; Warrington, Nicole M.; Oei, Ling; Ring, Susan M.; Kruithof, Claudia J.; Timpson, Nicholas J.; Wolber, Lisa E.; Reppe, Sjur; Gautvik, Kaare; Grundberg, Elin; Ge, Bing; van der Eerden, Bram; van de Peppel, Jeroen; Hibbs, Matthew A.; Ackert-Bicknell, Cheryl L.; Choi, Kwangbom; Koller, Daniel L.; Econs, Michael J.; Williams, Frances M. K.; Foroud, Tatiana; Carola Zillikens, M.; Ohlsson, Claes; Hofman, Albert; Uitterlinden, André G.; Davey Smith, George; Jaddoe, Vincent W. V.; Tobias, Jonathan H.; Rivadeneira, Fernando; Evans, David M.
2014-01-01
Heritability of bone mineral density (BMD) varies across skeletal sites, reflecting different relative contributions of genetic and environmental influences. To quantify the degree to which common genetic variants tag and environmental factors influence BMD, at different sites, we estimated the genetic (rg) and residual (re) correlations between BMD measured at the upper limbs (UL-BMD), lower limbs (LL-BMD) and skull (SK-BMD), using total-body DXA scans of ∼4,890 participants recruited by the Avon Longitudinal Study of Parents and their Children (ALSPAC). Point estimates of rg indicated that appendicular sites have a greater proportion of shared genetic architecture (LL-/UL-BMD rg = 0.78) between them, than with the skull (UL-/SK-BMD rg = 0.58 and LL-/SK-BMD rg = 0.43). Likewise, the residual correlation between BMD at appendicular sites (re = 0.55) was higher than the residual correlation between SK-BMD and BMD at appendicular sites (re = 0.20–0.24). To explore the basis for the observed differences in rg and re, genome-wide association meta-analyses were performed (n∼9,395), combining data from ALSPAC and the Generation R Study identifying 15 independent signals from 13 loci associated at genome-wide significant level across different skeletal regions. Results suggested that previously identified BMD-associated variants may exert site-specific effects (i.e. differ in the strength of their association and magnitude of effect across different skeletal sites). In particular, variants at CPED1 exerted a larger influence on SK-BMD and UL-BMD when compared to LL-BMD (P = 2.01×10−37), whilst variants at WNT16 influenced UL-BMD to a greater degree when compared to SK- and LL-BMD (P = 2.31×10−14). In addition, we report a novel association between RIN3 (previously associated with Paget's disease) and LL-BMD (rs754388: β = 0.13, SE = 0.02, P = 1.4×10−10). Our results suggest that BMD at different skeletal sites is under a mixture of shared and specific genetic and environmental influences. Allowing for these differences by performing genome-wide association at different skeletal sites may help uncover new genetic influences on BMD. PMID:24945404
Pathogenesis of myasthenia gravis: update on disease types, models, and mechanisms
Phillips, William D.; Vincent, Angela
2016-01-01
Myasthenia gravis is an autoimmune disease of the neuromuscular junction (NMJ) caused by antibodies that attack components of the postsynaptic membrane, impair neuromuscular transmission, and lead to weakness and fatigue of skeletal muscle. This can be generalised or localised to certain muscle groups, and involvement of the bulbar and respiratory muscles can be life threatening. The pathogenesis of myasthenia gravis depends upon the target and isotype of the autoantibodies. Most cases are caused by immunoglobulin (Ig)G1 and IgG3 antibodies to the acetylcholine receptor (AChR). They produce complement-mediated damage and increase the rate of AChR turnover, both mechanisms causing loss of AChR from the postsynaptic membrane. The thymus gland is involved in many patients, and there are experimental and genetic approaches to understand the failure of immune tolerance to the AChR. In a proportion of those patients without AChR antibodies, antibodies to muscle-specific kinase (MuSK), or related proteins such as agrin and low-density lipoprotein receptor-related protein 4 (LRP4), are present. MuSK antibodies are predominantly IgG4 and cause disassembly of the neuromuscular junction by disrupting the physiological function of MuSK in synapse maintenance and adaptation. Here we discuss how knowledge of neuromuscular junction structure and function has fed into understanding the mechanisms of AChR and MuSK antibodies. Myasthenia gravis remains a paradigm for autoantibody-mediated conditions and these observations show how much there is still to learn about synaptic function and pathological mechanisms. PMID:27408701
Structure of the horseradish peroxidase isozyme C genes.
Fujiyama, K; Takemura, H; Shibayama, S; Kobayashi, K; Choi, J K; Shinmyo, A; Takano, M; Yamada, Y; Okada, H
1988-05-02
We have isolated, cloned and characterized three cDNAs and two genomic DNAs corresponding to the mRNAs and genes for the horseradish (Armoracia rusticana) peroxidase isoenzyme C (HPR C). The amino acid sequence of HRP C1, deduced from the nucleotide sequence of one of the cDNA clone, pSK1, contained the same primary sequence as that of the purified enzyme established by Welinder [FEBS Lett. 72, 19-23 (1976)] with additional sequences at the N and C terminal. All three inserts in the cDNA clones, pSK1, pSK2 and pSK3, coded the same size of peptide (308 amino acid residues) if these are processed in the same way, and the amino acid sequence were homologous to each other by 91-94%. Functional amino acids, including His40, His170, Tyr185 and Arg183 and S-S-bond-forming Cys, were conserved in the three isozymes, but a few N-glycosylation sites were not the same. Two HRP C isoenzyme genomic genes, prxC1 and prxC2, were tandem on the chromosomal DNA and each gene consisted of four exons and three introns. The positions in the exons interrupted by introns were the same in two genes. We observed a putative promoter sequence 5' upstream and a poly(A) signal 3' downstream in both genes. The gene product of prxC1 might be processed with a signal sequence of 30 amino acid residues at the N terminus and a peptide consisting of 15 amino acid residues at the C terminus.
Sadeghzadeh, Masoud; Salahinejad, Maryam; Zarezadeh, Nahid; Ghandi, Mehdi; Baghery, Maryam Keshavarz
2017-11-01
In current study, antitumor activity of two series of the newly synthesized spiropyrroloquinoline isoindolinone and spiropyrroloquinoline aza-isoindolinone scaffolds was evaluated against three human breast normal and cancer cell lines (MCF-10A, MCF-7 and SK-BR-3) and compared with cytotoxicity values of doxorubicin and colchicine as the standard drugs. It was found that several compounds were endowed with cytotoxicity in the low micromolar range. Among these two series, compounds 6i, 6j, 6k and 7l, 7m, 7n, 7o containing 3-ethyl-1H-indole moiety were found to be highly effective against both cancer cell lines ranging from [Formula: see text] to [Formula: see text] in comparison with the corresponding analogs. Compared with human cancer cells, the most potent compounds did not show high cytotoxicity against human breast normal MCF-10A cells. Generally, most of the evaluated compounds 6a-l and 7a-o series showed more antitumor activity against SK-BR-3 than MCF-7 cells. Moreover, comparative molecular field analysis (CoMFA) as a popular tools of three-dimensional quantitative structure-activity relationship (3D-QSAR) studies was carried out on 27 spiropyrroloquinolineisoindolinone and spiropyrroloquinolineaza-isoindolinone derivatives with antitumor activity against on SK-BR-3 cells. The obtained CoMFA models showed statistically excellent performance, which also possessed good predictive ability for an external test set. The results confirm the important effect of molecular steric and electrostatic interactions of these compounds on in vitro cytotoxicity against SK-BR-3.
Characterization of CD4 and CD8 T Cell Responses in MuSK Myasthenia Gravis
Yi, JS; Guidon, A; Sparks, S; Osborne, R; Juel, VC; Massey, JM; Sanders, DB; Weinhold, KJ; Guptill, JT
2014-01-01
Muscle specific tyrosine kinase myasthenia gravis (MuSK MG) is a form of autoimmune MG that predominantly affects women and has unique clinical features, including prominent bulbar weakness, muscle atrophy, and excellent response to therapeutic plasma exchange. Patients with MuSK MG have predominantly IgG4 autoantibodies directed against MuSK on the postsynaptic muscle membrane. Lymphocyte functionality has not been reported in this condition. The goal of this study was to characterize T-cell responses in patients with MuSK MG. Intracellular production of IFN-gamma, TNF-alpha, IL-2, IL-17, and IL-21 by CD4+ and CD8+ T-cells was measured by polychromatic flow cytometry in peripheral blood samples from 11 Musk MG patients and 10 healthy controls. Only one MuSK MG patient was not receiving immunosuppressive therapy. Regulatory T-cells (Treg) were also included in our analysis to determine if changes in T cell function were due to altered Treg frequencies. CD8+ T-cells from MuSK MG patients had higher frequencies of polyfunctional responses than controls, and CD4+ T-cells had higher IL-2, TNF-alpha, and IL-17. MuSK MG patients had a higher percentage of CD4+ T-cells producing combinations of IFN-gamma/IL-2/TNF-gamma, TNF-alpha/IL-2, and IFN-gamma/TNF-alpha. Interestingly, Treg numbers and CD39 expression were not different from control values. MuSK MG patients had increased frequencies of Th1 and Th17 cytokines and were primed for polyfunctional proinflammatory responses that cannot be explained by a defect in Treg function or number. PMID:24378287
Yang, MeiYing; Camara, Amadou K.S.; Aldakkak, Mohammed; Kwok, Wai-Meng; Stowe, David F.
2017-01-01
We provide evidence for location and function of a small conductance, Ca2+-activated K+ (SKCa) channel isoform 3 (SK3) in mitochondria (m) of guinea pig, rat and human ventricular myocytes. SKCa agonists protected isolated hearts and mitochondria against ischemia/reperfusion (IR) injury; SKCa antagonists worsened IR injury. Intravenous infusion of a SKCa channel agonist/antagonist, respectively, in intact rats was effective in reducing/enhancing regional infarct size induced by coronary artery occlusion. Localization of SK3 in mitochondria was evidenced by Western blot of inner mitochondrial membrane, immunocytochemical staining of cardiomyocytes, and immunogold labeling of isolated mitochondria. We identified a SK3 splice variant in guinea pig (SK3.1, aka SK3a) and human ventricular cells (SK3.2) by amplifying mRNA, and show mitochondrial expression in mouse atrial tumor cells (HL-1) by transfection with full length and truncated SK3.1 protein. We found that the Nterminus is not required for mitochondrial trafficking but the C-terminus beyond the Ca2+ calmodulin binding domain is required for Ca2+ sensing to induce mK+ influx and/or promote mitochondrial localization. In isolated guinea pig mitochondria and in SK3 overexpressed HL-1 cells, mK+ influx was driven by adding CaCl2. Moreover, there was a greater fall in membrane potential (ΔΨm), and enhanced cell death with simulated cell injury after silencing SK3.1 with siRNA. Although SKCa channel opening protects the heart and mitochondria against IR injury, the mechanism for favorable bioenergetics effects resulting from SKCa channel opening remains unclear. SKCa channels could play an essential role in restraining cardiac mitochondria from inducing oxidative stress-induced injury resulting from mCa2+ overload. PMID:28342809
Scholl, Elizabeth Storer; Pirone, Antonella; Cox, Daniel H; Duncan, R Keith; Jacob, Michele H
2014-01-01
Small conductance Ca2+-sensitive potassium (SK2) channels are voltage-independent, Ca2+-activated ion channels that conduct potassium cations and thereby modulate the intrinsic excitability and synaptic transmission of neurons and sensory hair cells. In the cochlea, SK2 channels are functionally coupled to the highly Ca2+ permeant α9/10-nicotinic acetylcholine receptors (nAChRs) at olivocochlear postsynaptic sites. SK2 activation leads to outer hair cell hyperpolarization and frequency-selective suppression of afferent sound transmission. These inhibitory responses are essential for normal regulation of sound sensitivity, frequency selectivity, and suppression of background noise. However, little is known about the molecular interactions of these key functional channels. Here we show that SK2 channels co-precipitate with α9/10-nAChRs and with the actin-binding protein α-actinin-1. SK2 alternative splicing, resulting in a 3 amino acid insertion in the intracellular 3′ terminus, modulates these interactions. Further, relative abundance of the SK2 splice variants changes during developmental stages of synapse maturation in both the avian cochlea and the mammalian forebrain. Using heterologous cell expression to separately study the 2 distinct isoforms, we show that the variants differ in protein interactions and surface expression levels, and that Ca2+ and Ca2+-bound calmodulin differentially regulate their protein interactions. Our findings suggest that the SK2 isoforms may be distinctly modulated by activity-induced Ca2+ influx. Alternative splicing of SK2 may serve as a novel mechanism to differentially regulate the maturation and function of olivocochlear and neuronal synapses. PMID:24394769
MuSK myasthenia gravis and pregnancy.
Santos, Ernestina; Braga, Antonio; Gabriel, Denis; Duarte, Sara; Martins da Silva, Ana; Matos, Ilda; Freijo, Marta; Martins, Joao; Silveira, Fernando; Nadais, Goreti; Sousa, Filipa; Fraga, Carla; Santos Silva, Rosa; Lopes, Carlos; Gonçalves, Guilherme; Pinto, Clara; Sousa Braga, Jorge; Leite, Maria Isabel
2018-02-01
Muscle specific kinase (MuSK) myasthenia gravis (MG, MuSK-MG) is a rare subgroup of MG affecting mainly women during childbearing years. We investigated the influence of pregnancy in the course of MuSK-MG and pregnancy outcomes in females with MuSK-MG. A multicentre cohort of 17 women with MuSK-MG was studied retrospectively; 13 of them with ≥1 pregnancy. MuSK-MG onset age was 35,4 years; 23,0% had other autoimmune disorder; 46,2% were treatment refractory. Thirteen women experienced 27 pregnancies, either after MG onset (group I) (n = 4; maternal age at conception = 29.8 years) or before MG onset (group II) (n = 23; maternal age at conception = 26.2 years). In group I pregnancy occurred in average 9.8 years after the MG onset; it occurred in average 17.0 years before MG in group II. In group I, all were on steroids at time of conception, one on azathioprine and another receiving IVIG regularly. There were mild exacerbations that responded to treatment adjustments. There were no relapses in the 12 months following the delivery. There was no pre-eclampsia, birth defects or stillbirths in either group; 3 miscarriages in group II. One case of neonatal MG was recorded. In this small series, pregnancy did not seem to precipitate MuSK-MG or to have a major influence in the MuSK-MG course, and there was no apparent negative impact in pregnancy outcomes in those where pregnancy followed the MG onset. The weight was lower in the newborn of the group I mothers, although none had low birth weight. Copyright © 2017 Elsevier B.V. All rights reserved.
Briese, Michael; Saal-Bauernschubert, Lena; Ji, Changhe; Moradi, Mehri; Ghanawi, Hanaa; Uhl, Michael; Appenzeller, Silke; Backofen, Rolf; Sendtner, Michael
2018-03-20
Disturbed RNA processing and subcellular transport contribute to the pathomechanisms of motoneuron diseases such as amyotrophic lateral sclerosis and spinal muscular atrophy. RNA-binding proteins are involved in these processes, but the mechanisms by which they regulate the subcellular diversity of transcriptomes, particularly in axons, are not understood. Heterogeneous nuclear ribonucleoprotein R (hnRNP R) interacts with several proteins involved in motoneuron diseases. It is located in axons of developing motoneurons, and its depletion causes defects in axon growth. Here, we used individual nucleotide-resolution cross-linking and immunoprecipitation (iCLIP) to determine the RNA interactome of hnRNP R in motoneurons. We identified ∼3,500 RNA targets, predominantly with functions in synaptic transmission and axon guidance. Among the RNA targets identified by iCLIP, the noncoding RNA 7SK was the top interactor of hnRNP R. We detected 7SK in the nucleus and also in the cytosol of motoneurons. In axons, 7SK localized in close proximity to hnRNP R, and depletion of hnRNP R reduced axonal 7SK. Furthermore, suppression of 7SK led to defective axon growth that was accompanied by axonal transcriptome alterations similar to those caused by hnRNP R depletion. Using a series of 7SK-deletion mutants, we show that the function of 7SK in axon elongation depends on its interaction with hnRNP R but not with the PTEF-B complex involved in transcriptional regulation. These results propose a role for 7SK as an essential interactor of hnRNP R to regulate its function in axon maintenance. Copyright © 2018 the Author(s). Published by PNAS.
Lai, Juo-Hsin; Yang, Jhih-Tian; Chern, Jeffy; Chen, Te-Li; Wu, Wan-Ling; Liao, Jiahn-Haur; Tsai, Shih-Feng; Liang, Suh-Yuen; Chou, Chi-Chi; Wu, Shih-Hsiung
2016-01-01
Nosocomial infectious outbreaks caused by multidrug-resistant Acinetobacter baumannii have emerged as a serious threat to human health. Phosphoproteomics of pathogenic bacteria has been used to identify the mechanisms of bacterial virulence and antimicrobial resistance. In this study, we used a shotgun strategy combined with high-accuracy mass spectrometry to analyze the phosphoproteomics of the imipenem-susceptible strain SK17-S and -resistant strain SK17-R. We identified 410 phosphosites on 248 unique phosphoproteins in SK17-S and 285 phosphosites on 211 unique phosphoproteins in SK17-R. The distributions of the Ser/Thr/Tyr/Asp/His phosphosites in SK17-S and SK17-R were 47.0%/27.6%/12.4%/8.0%/4.9% versus 41.4%/29.5%/17.5%/6.7%/4.9%, respectively. The Ser-90 phosphosite, located on the catalytic motif S(88)VS(90)K of the AmpC β-lactamase, was first identified in SK17-S. Based on site-directed mutagenesis, the nonphosphorylatable mutant S90A was found to be more resistant to imipenem, whereas the phosphorylation-simulated mutant S90D was sensitive to imipenem. Additionally, the S90A mutant protein exhibited higher β-lactamase activity and conferred greater bacterial protection against imipenem in SK17-S compared with the wild-type. In sum, our results revealed that in A. baumannii, Ser-90 phosphorylation of AmpC negatively regulates both β-lactamase activity and the ability to counteract the antibiotic effects of imipenem. These findings highlight the impact of phosphorylation-mediated regulation in antibiotic-resistant bacteria on future drug design and new therapies. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
Lai, Juo-Hsin; Yang, Jhih-Tian; Chern, Jeffy; Chen, Te-Li; Wu, Wan-Ling; Liao, Jiahn-Haur; Tsai, Shih-Feng; Liang, Suh-Yuen; Chou, Chi-Chi
2016-01-01
Nosocomial infectious outbreaks caused by multidrug-resistant Acinetobacter baumannii have emerged as a serious threat to human health. Phosphoproteomics of pathogenic bacteria has been used to identify the mechanisms of bacterial virulence and antimicrobial resistance. In this study, we used a shotgun strategy combined with high-accuracy mass spectrometry to analyze the phosphoproteomics of the imipenem-susceptible strain SK17-S and -resistant strain SK17-R. We identified 410 phosphosites on 248 unique phosphoproteins in SK17-S and 285 phosphosites on 211 unique phosphoproteins in SK17-R. The distributions of the Ser/Thr/Tyr/Asp/His phosphosites in SK17-S and SK17-R were 47.0%/27.6%/12.4%/8.0%/4.9% versus 41.4%/29.5%/17.5%/6.7%/4.9%, respectively. The Ser-90 phosphosite, located on the catalytic motif S88VS90K of the AmpC β-lactamase, was first identified in SK17-S. Based on site-directed mutagenesis, the nonphosphorylatable mutant S90A was found to be more resistant to imipenem, whereas the phosphorylation-simulated mutant S90D was sensitive to imipenem. Additionally, the S90A mutant protein exhibited higher β-lactamase activity and conferred greater bacterial protection against imipenem in SK17-S compared with the wild-type. In sum, our results revealed that in A. baumannii, Ser-90 phosphorylation of AmpC negatively regulates both β-lactamase activity and the ability to counteract the antibiotic effects of imipenem. These findings highlight the impact of phosphorylation-mediated regulation in antibiotic-resistant bacteria on future drug design and new therapies. PMID:26499836
Forehead versus forearm skin vascular responses at presyncope in humans
Gagnon, Daniel; Matthew Brothers, R.; Ganio, Matthew S.; Hastings, Jeffrey L.
2014-01-01
Facial pallor is commonly observed at presyncope in humans, suggestive of reductions in facial skin blood flow (SkBF). Yet, cutaneous vasoconstriction is usually minimal at presyncope when measured at the forearm. We tested the hypothesis that reductions in forehead SkBF at presyncope are greater than in the forearm. Forehead and forearm SkBF (laser-Doppler) and blood pressure (Finometer or radial artery catheterization) were measured during lower body negative pressure (LBNP) to presyncope in 11 normothermic and 13 heat-stressed subjects (intestinal temperature increased ∼1.4°C). LBNP reduced mean arterial pressure from 91 ± 5 to 57 ± 7 mmHg during normothermia (P ≤ 0.001) and from 82 ± 5 to 57 ± 7 mmHg during heat stress (P ≤ 0.001). During normothermia, LBNP decreased forehead SkBF 55 ± 14% compared with 24 ± 11% at the forearm (P = 0.002), while during heat stress LBNP decreased forehead SkBF 39 ± 11% compared with 28 ± 8% in the forearm (P = 0.007). In both conditions, most (≥68%) of the decreases in SkBF were due to decreases in blood pressure. However, a greater contribution of actively mediated reductions in SkBF was observed at the forehead, relative to the forearm during normothermia (32 ± 13% vs. 11 ± 11%, P = 0.031) and heat stress (30 ± 13% vs. 10 ± 13%, P = 0.004). These data suggest that facial pallor at presyncope is due to a combination of passive decreases in forehead SkBF secondary to reductions in blood pressure and to active decreases in SkBF, the latter of which are relatively greater than in the forearm. PMID:25100073
Management Training and Development within Its Environment: The Case of Libyan Industrial Companies.
ERIC Educational Resources Information Center
Agnaia, Almehdi A.
1997-01-01
A survey of 45 Libyan industrial companies found that many were owned/managed by government agencies. Management training and development were constrained by political, social, and economic factors, such as policies and laws, customs and beliefs about work, and import/export restrictions. (SK)
Impact of Sociodemographic Factors on Perceived Importance of Nutrition in Food Shopping.
ERIC Educational Resources Information Center
Nayga, Rodolfo M., Jr.
1997-01-01
Household meal planners (n=1,498) were surveyed. Characteristics of those who perceive nutrition to be important in food shopping were as follows: black, female, higher education level, nonworking, and/or urban. Results could guide design of nutrition information and food marketing programs. (SK)
Factors Influencing Students' Peer Evaluation in Cooperative Learning.
ERIC Educational Resources Information Center
Persons, Obeua S.
1998-01-01
In an accounting class in which 25% of grades were derived from group work, students completed peer evaluations. Regression analyses revealed that accounting majors and students with higher grade point averages received higher peer evaluations. Higher group homework and class participation grades were associated with higher peer evaluations. (SK)
Etiology of Drinking and Driving among Adolescents: Implications for Primary Prevention.
ERIC Educational Resources Information Center
Klepp, Knut-Inge; And Others
1991-01-01
A survey of 1,482 high school students in spring and fall 1986 resulted in confirmation of the Problem Behavior Theory as a predictor of drinking and driving among adolescents. Environmental, behavioral, and demographic factors account for 50 percent of the variance in drinking and driving. (SK)
ERIC Educational Resources Information Center
Johanson, Ulf
1998-01-01
Presents components of human resource accounting (HRA)--description of human resource costs, estimation of return on investment, estimation of human resource values. Reviews research on the influence of HRA on decision making, concluding that a number of factors inhibit its effective use. (SK)
ERIC Educational Resources Information Center
Jain, Hem C.
1990-01-01
Examines differences between Japanese and North American personnel management philosophies. Considers to what extent practices of Japanese corporations have been transferred to subsidiaries in Canada, India, Malaysia, and Singapore, compared to locally owned firms. Shows how cultural factors affect styles of personnel management. (SK)
Pre-Employment Testing on the Internet: Put Candidates a Click Away and Hire at Modem Speed.
ERIC Educational Resources Information Center
Mooney, John
2002-01-01
The experience of a county government illustrates factors to consider in implementing online employment testing for job candidates: (1) selection of the appropriate Internet-based test; (2) passwords, timing, security, and technical difficulties; and (3) provisions for applicants who lack Internet access. (SK)
ERIC Educational Resources Information Center
Harbstreit, Steven R.; Welton, Richard F.
1992-01-01
Responses from 1,008 of 1,398 secondary agricultural students in Kansas found (1) limited awareness of international agricultural products and policy, geography, and other cultures; and (2) awareness increased among students with higher grades, longer time in agricultural programs, or involvement in supervised occupational experience. (SK)
ERIC Educational Resources Information Center
Raffo, Carlo; Lovatt, Andy; Banks, Mark; O'Connor, Justin
2000-01-01
A study of 50 entrepreneurs in small businesses (fashion design, entertainment, new media) identified factors that helped them learn and develop their business, especially situated learning, networking, and mentoring. Similar naturalistic approaches are recommended for further and higher education focused on entrepreneurship. (SK)
Single-Site, Results-Level Evaluation of Quality Awareness Training.
ERIC Educational Resources Information Center
Murray, Brian; Raffaele, Gary C.
1997-01-01
An interrupted time-series design pooling 6 12-year series evaluated the long-term effects of a quality training intervention in a factory. Training positively affected quality of goods and dollar utility. Production process was an important contextual factor in assessing the effect size of the intervention. (SK)
Consumer Decision-Making Styles as a Function of Individual Learning Styles.
ERIC Educational Resources Information Center
Sproles, Elizabeth Kendall; Sproles, George B.
1990-01-01
The Secondary Learning Styles Inventory and the Consumer Styles Inventory were administered to 501 secondary home economics students. Factor analysis of the learning style characteristics from the sample of 482 found significant correlations between 21 of the 48 pairs of learning and decision-making characteristics. (SK)
The Relationship of Personality Traits and Self-Monitoring Behavior to Choice of Business Major.
ERIC Educational Resources Information Center
Noel, Noel Mark; Michaels Chad; Levas, Michael G.
2003-01-01
Using Cattell's 16 Personality Factor Questionnaire and the Revised Self-Monitoring Scale, 177 undergraduate business students assessed their personality traits. Personalities and self-monitoring differed by major (accounting, management information systems, marketing) in ways that supported conventional stereotypes. (Contains 24 references.) (SK)
ERIC Educational Resources Information Center
Wentling, Rose Mary
1992-01-01
According to interviews with 30 women in middle management, 4 factors pertinent to their success were educational credentials, hard work, mentors, and interpersonal skills. Barriers to career development were supervisors/directors, sex discrimination, lack of political savvy, and lack of career strategy. (SK)
Job Tenure and Joblessness of Displaced Workers.
ERIC Educational Resources Information Center
Valletta, Robert G.
1991-01-01
Data from the Displaced Worker Survey found that, for men, the duration of joblessness increases with the length of job tenure (15 years or more), consistent with the hypothesis that male workers base reservation wages on factors such as accumulated human capital that raise current wages more than potential wage offers. (SK)
Akatsu, Masahiko; Ikegami, Yukihiro; Tase, Choichiro; Nishikawa, Koichi
2017-03-15
Myasthenia gravis (MG) is an autoimmune disease characterized by the production of antibodies against the acetylcholine receptor, muscle-specific kinase (MuSK), or other proteins at the neuromuscular junction. MG with antibodies against MuSK (MuSK-MG) has been described recently. Here, we report the first case of anesthetic management of a patient with MuSK-MG undergoing an open cholecystectomy. In our case, propofol and remifentanil-based anesthesia were used for successful management without using muscle relaxants. Patients with MuSK-MG have predominantly ocular, bulbar, and respiratory symptoms that may increase the risk of aspiration. Anesthesiologists need to pay attention to perioperative respiratory failure and respiratory crisis.
Comparing two tetraalkylammonium ionic liquids. I. Liquid phase structure
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lima, Thamires A.; Paschoal, Vitor H.; Faria, Luiz F. O.
2016-06-14
X-ray scattering experiments at room temperature were performed for the ionic liquids n-butyl-trimethylammonium bis(trifluoromethanesulfonyl)imide, [N{sub 1114}][NTf{sub 2}], and methyl-tributylammonium bis(trifluoromethanesulfonyl)imide, [N{sub 1444}][NTf{sub 2}]. The peak in the diffraction data characteristic of charge ordering in [N{sub 1444}][NTf{sub 2}] is shifted to longer distances in comparison to [N{sub 1114}][NTf{sub 2}], but the peak characteristic of short-range correlations is shifted in [N{sub 1444}][NTf{sub 2}] to shorter distances. Molecular dynamics (MD) simulations were performed for these ionic liquids using force fields available from the literature, although with new sets of partial charges for [N{sub 1114}]{sup +} and [N{sub 1444}]{sup +} proposed in this work.more » The shifting of charge and adjacency peaks to opposite directions in these ionic liquids was found in the static structure factor, S(k), calculated by MD simulations. Despite differences in cation sizes, the MD simulations unravel that anions are allowed as close to [N{sub 1444}]{sup +} as to [N{sub 1114}]{sup +} because anions are located in between the angle formed by the butyl chains. The more asymmetric molecular structure of the [N{sub 1114}]{sup +} cation implies differences in partial structure factors calculated for atoms belonging to polar or non-polar parts of [N{sub 1114}][NTf{sub 2}], whereas polar and non-polar structure factors are essentially the same in [N{sub 1444}][NTf{sub 2}]. Results of this work shed light on controversies in the literature on the liquid structure of tetraalkylammonium based ionic liquids.« less
Multidimensional scaling of ideological landscape on social network sites
NASA Astrophysics Data System (ADS)
Lee, Deokjae; Hahn, Kyu S.; Park, Juyong
2012-02-01
Social network sites (SNSs) are valuable source of information on various subjects in network science. Recently, political activity of SNSs users has increasing attention and is an interesting interdisciplinary subject of physical and social science. In this work, we measure ideological positions of the legislators of U.S. and South Korea (S.K.) evaluated by Twitter users, using the information employed in the bipartite network structure of the legislators and their Twitter followers. We compare the result with ideological positions constructed from roll call record of the legislators. This shows there is a discrepancy between the ideological positions evaluated by Twitter users and actual positions estimated from roll call votes in S.K. We also asses the ideological positions of the Twitter users themselves and analyze the distribution of the positions.
Jones, Scott L; To, Minh-Son; Stuart, Greg J
2017-10-23
Small conductance calcium-activated potassium channels (SK channels) are present in spines and can be activated by backpropagating action potentials (APs). This suggests they may play a critical role in spike-timing dependent synaptic plasticity (STDP). Consistent with this idea, EPSPs in both cortical and hippocampal pyramidal neurons were suppressed by preceding APs in an SK-dependent manner. In cortical pyramidal neurons EPSP suppression by preceding APs depended on their precise timing as well as the distance of activated synapses from the soma, was dendritic in origin, and involved SK-dependent suppression of NMDA receptor activation. As a result SK channel activation by backpropagating APs gated STDP induction during low-frequency AP-EPSP pairing, with both LTP and LTD absent under control conditions but present after SK channel block. These findings indicate that activation of SK channels in spines by backpropagating APs plays a key role in regulating both EPSP amplitude and STDP induction.
Defining Role in the New Classroom Teams.
ERIC Educational Resources Information Center
Thomas, Gary
1991-01-01
Interviews with four teachers, one parent, one assistant, and two ancillary helpers found that classroom teams possess little structure with minimal role definition. Participants erect defenses against the lack of definition and use a process termed "fraternity" to get along with one another and camouflage uncertainties and tensions. (SK)
Athene in Academe: Women Mentoring Women in the Academy.
ERIC Educational Resources Information Center
Stalker, Joyce
1994-01-01
Traditionally conceived, mentoring has a male orientation that ignores women's experience as "same" and "other" in academia and the problems of men mentoring women and of women mentors socializing mentees into acceptance of the patriarchal system. An alternative view values women's unique position and critiques existing power structures. (SK)
The Work/Family Challenge: A Key Career Development Issue.
ERIC Educational Resources Information Center
Kahnweiler, William M; Kahnweiler, Jennifer B.
1992-01-01
A few corporations are responding to the impact of family structural changes on workers' ability to balance their roles with flexible benefits and schedules and with training. Work/family issues are an integral part of career and life decision making and must be incorporated into the career development process. (SK)
Skin Resistivity Value of Upper Trapezius Latent Trigger Points
Skorupska, Elżbieta; Zawadziński, Jarosław
2015-01-01
Introduction. The skin resistivity (SkR) measurement is commonly recommended for acupoints measurement, but for trigger points (TrPs) only one study is available. The purpose of the study was to evaluate SkR for latent TrPs compared to non-TrPs and the surrounding tissue. Material and Methods. Forty-two healthy volunteers with unilateral latent upper trapezius TrPs (12 men, 30 women) aged 21–23 (mean age: 22.1 ± 0.6 y) participated in the study. Keithley electrometer 610B was used for measuring SkR (Ag/AgCl self-adhesive, disposable ground electrode: 30 mm diameter). SkR was measured for latent TrPs and compared to opposite non-TrPs sites and the surrounding tissue. Results. The SkR decrease of TrPs-positive sites as compared to TrPs-negative sites and the surrounding tissue was confirmed. However, no statistically significant difference in the SkR value occurred when all data were analyzed. The same was confirmed after gender division and for TrPs-positive subjects examined for referred pain and twitch response presence. Conclusion. SkR reactive changes at latent TrPs are possible but the results were not consistent with the previous study. Thus, caution in applying SkR to latent TrPs isolation is recommended and its clinical use should not be encouraged yet. Further studies, especially on active TrPs, are yet required. PMID:26180796
Niu, Chengtuo; Zhu, Linjiang; Zhu, Pei; Li, Qi
2015-06-03
1,3-1,4-β-Glucanase is widely applied in the food industry, while its low thermostability often reduces its performance. In a previous study, chemical modification of surface lysine residues was proved to increase the thermostability of β-glucanase. To improve the thermostability, the mesophilic β-glucanase from Bacillus terquilensis was rationally engineered through site-directed mutagenesis of the 12 lysines into serines. The results showed that the K20S, K117S, and K165S mutants could both enhance the specific activities and thermostability of β-glucanase. The triple mutant (K20S/K117S/K165S) could increase the optimal temperature and T50 value by 15 and 14 °C, respectively. Five percent more structured residues were observed in the mutant, which formed new β-sheet structures in the concave side. Molecular dynamics simulation analysis showed that the flexibility in the mutation regions was decreased, which resulted in the overall rigidity of the β-glucanase. Therefore, the lysine-based site-directed mutagenesis is a simple and effective method for improving the thermostability of β-glucanase.
Role of miR-132 in Angiogenesis after Ocular Infection with Herpes Simplex Virus
Mulik, Sachin; Xu, John; Reddy, Pradeep B.J.; Rajasagi, Naveen K.; Gimenez, Fernanda; Sharma, Shalini; Lu, Patrick Y.; Rouse, Barry T.
2013-01-01
MicroRNAs (miRNAs) are small regulatory molecules that control diverse biological processes that include angiogenesis. Herpes simplex virus (HSV) causes a chronic immuno-inflammatory response in the eye that may result in corneal neovascularization during blinding immunopathological lesion stromal keratitis (SK). miR-132 is a highly conserved miRNA that is induced in endothelial cells in response to growth factors, such as vascular endothelial growth factor (VEGF). In this study, we show that miR-132 expression was up-regulated (10- to 20-fold) after ocular infection with HSV, an event that involved the production of both VEGF-A and IL-17. Consequently, blockade of VEGF-A activity using soluble VEGF receptor 1 resulted in significantly lower levels of corneal miR-132 after HSV infection. In addition, low levels of corneal miR-132 were detected in IL-17 receptor knockout mice after HSV infection. In vivo silencing of miR-132 by the provision of anti-miR-132 (antagomir-132) nanoparticles to HSV-infected mice led to reduced corneal neovascularization and diminished SK lesions. The anti-angiogenic effect of antagomir-132 was reflected by a reduction in angiogenic Ras activity in corneal CD31-enriched cells (presumably blood vessel endothelial cells) during SK. To our knowledge, this is one of the first reports of miRNA involvement in an infectious ocular disease. Manipulating miRNA expression holds promise as a therapeutic approach to control an ocular lesion that is an important cause of human blindness. PMID:22659469
Role of miR-132 in angiogenesis after ocular infection with herpes simplex virus.
Mulik, Sachin; Xu, John; Reddy, Pradeep B J; Rajasagi, Naveen K; Gimenez, Fernanda; Sharma, Shalini; Lu, Patrick Y; Rouse, Barry T
2012-08-01
MicroRNAs (miRNAs) are small regulatory molecules that control diverse biological processes that include angiogenesis. Herpes simplex virus (HSV) causes a chronic immuno-inflammatory response in the eye that may result in corneal neovascularization during blinding immunopathological lesion stromal keratitis (SK). miR-132 is a highly conserved miRNA that is induced in endothelial cells in response to growth factors, such as vascular endothelial growth factor (VEGF). In this study, we show that miR-132 expression was up-regulated (10- to 20-fold) after ocular infection with HSV, an event that involved the production of both VEGF-A and IL-17. Consequently, blockade of VEGF-A activity using soluble VEGF receptor 1 resulted in significantly lower levels of corneal miR-132 after HSV infection. In addition, low levels of corneal miR-132 were detected in IL-17 receptor knockout mice after HSV infection. In vivo silencing of miR-132 by the provision of anti-miR-132 (antagomir-132) nanoparticles to HSV-infected mice led to reduced corneal neovascularization and diminished SK lesions. The anti-angiogenic effect of antagomir-132 was reflected by a reduction in angiogenic Ras activity in corneal CD31-enriched cells (presumably blood vessel endothelial cells) during SK. To our knowledge, this is one of the first reports of miRNA involvement in an infectious ocular disease. Manipulating miRNA expression holds promise as a therapeutic approach to control an ocular lesion that is an important cause of human blindness. Copyright © 2012 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.
A biological stone from a medieval cemetery in Poland.
Gładykowska-Rzeczycka, Judyta J; Nowakowski, Dariusz
2014-01-01
A review of the literature shows that origination of biological stones as well as their pathogenesis mostly depend on the environmental factors. As a result, the structural spectrum of such calculi and their chemical composition are highly diversified. It is well known that biological stones are formed mostly in the digestive and urinary tracts. However, it has been demonstrated that this kind of stony structure can be also, though rarely, found in circulatory and reproductive systems, skin, mucosa, and tear ducts. Although in palaeopathology, the list of biological stones is enriched by stony tumours and/or discharges, it is very difficult to uncover the small size deposits in excavation material. In the literature such findings, originating from different countries and centuries, are few. The described stone was found among the bones of an adult individual in the medieval cemetery of Gdańsk (Poland). The SEM, X-ray spectrometer and chemical evaluation revealed that it was a bladder calculus.
A Biological Stone from a Medieval Cemetery in Poland
Gładykowska-Rzeczycka, Judyta J.; Nowakowski, Dariusz
2014-01-01
A review of the literature shows that origination of biological stones as well as their pathogenesis mostly depend on the environmental factors. As a result, the structural spectrum of such calculi and their chemical composition are highly diversified. It is well known that biological stones are formed mostly in the digestive and urinary tracts. However, it has been demonstrated that this kind of stony structure can be also, though rarely, found in circulatory and reproductive systems, skin, mucosa, and tear ducts. Although in palaeopathology, the list of biological stones is enriched by stony tumours and/or discharges, it is very difficult to uncover the small size deposits in excavation material. In the literature such findings, originating from different countries and centuries, are few. The described stone was found among the bones of an adult individual in the medieval cemetery of Gdańsk (Poland). The SEM, X-ray spectrometer and chemical evaluation revealed that it was a bladder calculus. PMID:25275551
Sequencing and molecular dissection of Sk-2 in Neurospora
USDA-ARS?s Scientific Manuscript database
Neurospora Spore killer-2 is a selfish meiotic drive element that kills its non-Sk-2 siblings during sexual sporulation. Although the location of Sk-2 has been mapped to a large recombination-suppressed region of chromosome III, the physical length and exact borders of the element have remained unde...
Asahina, Masato; Akaogi, Yuichi; Yamanaka, Yoshitaka; Koyama, Yu; Hattori, Takamichi
2009-06-01
Certain stimuli evoke increased sweat secretion (sympathetic sweat response; SSwR) and reduced skin blood flow (skin vasomotor reflex; SkVR) in the palm/sole. We evaluated SSwR and SkVR in patients with multiple system atrophy (MSA) and pure autonomic failure (PAF). SSwR and SkVR on the palm in response to deep inspiration and mental arithmetic were recorded in 11 MSA patients, 11 PAF patients, and 11 healthy controls. In addition, the head-up tilt test was performed, and the coefficient of variation of R-R intervals (CV(R-R)) was obtained. SSwR amplitudes were significantly lower in the MSA and PAF patients than the controls. SkVR amplitudes in the PAF patients were significantly lower than the controls, but preserved in the MSA patients. In head-up tilt tests, all MSA and PAF patients showed orthostatic hypotension, with similar severity. CV(R-R) was low in the MSA and PAF patients, but a significant difference was found only between the PAF and control groups. In the MSA patients, SkVR was preserved, but SSwR was diminished. In the PAF patients, both SkVR and SSwR were attenuated. The combination of SkVR and SSwR tests may differentiate MSA and PAF.
Solar neutrino measurements in Super-Kamiokande-IV
NASA Astrophysics Data System (ADS)
Abe, K.; Haga, Y.; Hayato, Y.; Ikeda, M.; Iyogi, K.; Kameda, J.; Kishimoto, Y.; Marti, Ll.; Miura, M.; Moriyama, S.; Nakahata, M.; Nakajima, T.; Nakayama, S.; Orii, A.; Sekiya, H.; Shiozawa, M.; Sonoda, Y.; Takeda, A.; Tanaka, H.; Takenaga, Y.; Tasaka, S.; Tomura, T.; Ueno, K.; Yokozawa, T.; Akutsu, R.; Irvine, T.; Kaji, H.; Kajita, T.; Kametani, I.; Kaneyuki, K.; Lee, K. P.; Nishimura, Y.; McLachlan, T.; Okumura, K.; Richard, E.; Labarga, L.; Fernandez, P.; Blaszczyk, F. d. M.; Gustafson, J.; Kachulis, C.; Kearns, E.; Raaf, J. L.; Stone, J. L.; Sulak, L. R.; Berkman, S.; Tobayama, S.; Goldhaber, M.; Bays, K.; Carminati, G.; Griskevich, N. J.; Kropp, W. R.; Mine, S.; Renshaw, A.; Smy, M. B.; Sobel, H. W.; Takhistov, V.; Weatherly, P.; Ganezer, K. S.; Hartfiel, B. L.; Hill, J.; Keig, W. E.; Hong, N.; Kim, J. Y.; Lim, I. T.; Park, R. G.; Akiri, T.; Albert, J. B.; Himmel, A.; Li, Z.; O'Sullivan, E.; Scholberg, K.; Walter, C. W.; Wongjirad, T.; Ishizuka, T.; Nakamura, T.; Jang, J. S.; Choi, K.; Learned, J. G.; Matsuno, S.; Smith, S. N.; Friend, M.; Hasegawa, T.; Ishida, T.; Ishii, T.; Kobayashi, T.; Nakadaira, T.; Nakamura, K.; Nishikawa, K.; Oyama, Y.; Sakashita, K.; Sekiguchi, T.; Tsukamoto, T.; Nakano, Y.; Suzuki, A. T.; Takeuchi, Y.; Yano, T.; Cao, S. V.; Hayashino, T.; Hiraki, T.; Hirota, S.; Huang, K.; Ieki, K.; Jiang, M.; Kikawa, T.; Minamino, A.; Murakami, A.; Nakaya, T.; Patel, N. D.; Suzuki, K.; Takahashi, S.; Wendell, R. A.; Fukuda, Y.; Itow, Y.; Mitsuka, G.; Muto, F.; Suzuki, T.; Mijakowski, P.; Frankiewicz, K.; Hignight, J.; Imber, J.; Jung, C. K.; Li, X.; Palomino, J. L.; Santucci, G.; Taylor, I.; Vilela, C.; Wilking, M. J.; Yanagisawa, C.; Fukuda, D.; Ishino, H.; Kayano, T.; Kibayashi, A.; Koshio, Y.; Mori, T.; Sakuda, M.; Takeuchi, J.; Yamaguchi, R.; Kuno, Y.; Tacik, R.; Kim, S. B.; Okazawa, H.; Choi, Y.; Ito, K.; Nishijima, K.; Koshiba, M.; Totsuka, Y.; Suda, Y.; Yokoyama, M.; Bronner, C.; Calland, R. G.; Hartz, M.; Martens, K.; Obayashi, Y.; Suzuki, Y.; Vagins, M. R.; Nantais, C. M.; Martin, J. F.; de Perio, P.; Tanaka, H. A.; Konaka, A.; Chen, S.; Sui, H.; Wan, L.; Yang, Z.; Zhang, H.; Zhang, Y.; Connolly, K.; Dziomba, M.; Wilkes, R. J.; Super-Kamiokande Collaboration
2016-09-01
Upgraded electronics, improved water system dynamics, better calibration and analysis techniques allowed Super-Kamiokande-IV to clearly observe very low-energy 8B solar neutrino interactions, with recoil electron kinetic energies as low as ˜3.5 MeV . Super-Kamiokande-IV data-taking began in September of 2008; this paper includes data until February 2014, a total livetime of 1664 days. The measured solar neutrino flux is (2.308 ±0.020 (stat)-0.040 +0.039(syst ))×1 06/(cm2 sec ) assuming no oscillations. The observed recoil electron energy spectrum is consistent with no distortions due to neutrino oscillations. An extended maximum likelihood fit to the amplitude of the expected solar zenith angle variation of the neutrino-electron elastic scattering rate in SK-IV results in a day/night asymmetry of (-3.6 ±1.6 (stat )±0.6 (syst ))% . The SK-IV solar neutrino data determine the solar mixing angle as sin2θ12=0.327-0.031+0.026 , all SK solar data (SK-I, SK-II, SK III and SK-IV) measures this angle to be sin2θ12=0.334-0.023+0.027 , the determined mass-squared splitting is Δ m212=4.8-0.8+1.5×10-5 eV2 .
Processing of Nonconjugative Resistance Plasmids by Conjugation Nicking Enzyme of Staphylococci
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pollet, Rebecca M.; Ingle, James D.; Hymes, Jeff P.
Antimicrobial resistance inStaphylococcus aureuspresents an increasing threat to human health. This resistance is often encoded on mobile plasmids, such as pSK41; however, the mechanism of transfer of these plasmids is not well understood. In this study, we first examine key protein-DNA interactions formed by the relaxase enzyme, NES, which initiates and terminates the transfer of the multidrug resistance plasmid pSK41. Two loops on the NES protein, hairpin loops 1 and 2, form extensive contacts with the DNA hairpin formed at theoriTregion of pSK41, and here we establish that these contacts are essential for proper DNA cleavage and religation by themore » full 665-residue NES proteinin vitro. Second, pSK156 and pCA347 are nonconjugativeStaphylococcus aureusplasmids that contain sequences similar to theoriTregion of pSK41 but differ in the sequence predicted to form a DNA hairpin. We show that pSK41-encoded NES is able to bind, cleave, and religate theoriTsequences of these nonconjugative plasmidsin vitro. Although pSK41 could mobilize a coresident plasmid harboring its cognateoriT, it was unable to mobilize plasmids containing the pSK156 and pCA347 variantoriTmimics, suggesting that an accessory protein like that previously shown to confer specificity in the pWBG749 system may also be involved in transmission of plasmids containing a pSK41-likeoriT. These data indicate that the conjugative relaxase intransmechanism recently described for the pWBG749 family of plasmids also applies to the pSK41 family of plasmids, further heightening the potential significance of this mechanism in the horizontal transfer of staphylococcal plasmids. IMPORTANCEUnderstanding the mechanism of antimicrobial resistance transfer in bacteria such asStaphylococcus aureusis an important step toward potentially slowing the spread of antimicrobial-resistant infections. This work establishes protein-DNA interactions essential for the transfer of theStaphylococcus aureusmultiresistance plasmid pSK41 by its relaxase, NES. This enzyme also processed variantoriT-like sequences found on numerous plasmids previously considered nontransmissible, suggesting that in conjunction with an uncharacterized accessory protein, these plasmids may be transferred horizontally via a relaxase intransmechanism. These findings have important implications for our understanding of staphylococcal resistance plasmid evolution.« less
Kim, Bo Kwang; Kim, Kyoung Sun; Oh, Chul-Woong; Mykles, Donald L; Lee, Sung Gu; Kim, Hak Jun; Kim, Hyun-Woo
2009-06-01
Lobster muscles express a diverse array of myofibrillar protein isoforms. Three fiber types (fast, slow-twitch or S1, and slow-tonic or S2) differ qualitatively and quantitatively in myosin heavy and light chains, troponin-T, -I, and -C, paramyosin, and tropomyosin variants. However, little is known about the diversity of actin isoforms present in crustacean tissues. In this report we characterized cDNAs that encode twelve actin isoforms in the American lobster, Homarus americanus: eight from skeletal muscle (Ha-ActinSK1-8), one from heart (Ha-ActinHT1), and three cytoplasmic type actins from hepatopancreas (Ha-ActinCT1-3). All twelve cDNAs were products of distinct genes, as indicated by differences in the 3'-untranslated regions (UTRs). The open reading frames specified polypeptides 376 or 377 amino acids in length. Although key amino residues are conserved in the lobster actins, variations in nearby sequences may affect actin polymerization and/or interactions with other myofibrillar proteins. Quantitative reverse transcription-polymerase chain reaction showed muscle fiber type- and tissue-specific expression patterns. Ha-Actin-HT1 was expressed exclusively in heart (87% of the total; 12% of the total was Ha-ActinCT1). Ha-ActinCT1 was expressed in all tissues, while CT2 and CT3 were expressed only in hepatopancreas, with Ha-ActinCT2 as the major isoform (93% of the total). Ha-ActinSK1 and SK2 were the major isoforms (88% and 12% of the total, respectively) in the S1 fibers of crusher claw closer muscle. Fast fibers in the cutter claw closer and deep abdominal muscles differed in SK isoforms. Ha-ActinSK3, SK4, and SK5 were the major isoforms in cutter claw closer muscle (12%, 48%, and 37% of the total, respectively). Ha-ActinSK5 and SK8 were the major isoforms in deep abdominal flexor (31% and 65% of the total, respectively) and extensor (46% and 53% of the total, respectively) muscles, with SK6 and SK7 expressed at low levels. These data indicate that fast fibers in cutter claw and abdominal muscles show a phenotypic plasticity with respect to the expression of actin isoforms and may constitute discrete subtypes that differ in contractile properties.
Clift, Ian C.; Bamidele, Adebowale O.; Rodriguez-Ramirez, Christie; Kremer, Kimberly N.
2014-01-01
CXC chemokine receptor 4 (CXCR4) is a G protein–coupled receptor (GPCR) located on the cell surface that signals upon binding the chemokine stromal derived factor-1 (SDF-1; also called CXCL 12). CXCR4 promotes neuroblastoma proliferation and chemotaxis. CXCR4 expression negatively correlates with prognosis and drives neuroblastoma growth and metastasis in mouse models. All functions of CXCR4 require its expression on the cell surface, yet the molecular mechanisms that regulate CXCR4 cell-surface levels in neuroblastoma are poorly understood. We characterized CXCR4 cell-surface regulation in the related SH-SY5Y and SK-N-SH human neuroblastoma cell lines. SDF-1 treatment caused rapid down-modulation of CXCR4 in SH-SY5Y cells. Pharmacologic activation of protein kinase C similarly reduced CXCR4, but via a distinct mechanism. Analysis of CXCR4 mutants delineated two CXCR4 regions required for SDF-1 treatment to decrease cell-surface CXCR4 in neuroblastoma cells: the isoleucine-leucine motif at residues 328 and 329 and residues 343–352. In contrast, and unlike CXCR4 regulation in other cell types, serines 324, 325, 338, and 339 were not required. Arrestin proteins can bind and regulate GPCR cell-surface expression, often functioning together with kinases such as G protein–coupled receptor kinase 2 (GRK2). Using SK-N-SH cells which are naturally deficient in β-arrestin1, we showed that β-arrestin1 is required for the CXCR4 343–352 region to modulate CXCR4 cell-surface expression following treatment with SDF-1. Moreover, GRK2 overexpression enhanced CXCR4 internalization, via a mechanism requiring both β-arrestin1 expression and the 343–352 region. Together, these results characterize CXCR4 structural domains and β-arrestin1 as critical regulators of CXCR4 cell-surface expression in neuroblastoma. β-Arrestin1 levels may therefore influence the CXCR4-driven metastasis of neuroblastoma as well as prognosis. PMID:24452472
Zhang, Hongyou; Wu, Ling; Xu, Chuang; Xia, Cheng; Sun, Lingwei; Shu, Shi
2013-09-26
Ketosis is an important problem for dairy cows` production performance. However, it is still little known about plasma metabolomics details of dairy ketosis. A gas chromatography/mass spectrometry (GC/MS) technique was used to investigate plasma metabolic differences in cows that had clinical ketosis (CK, n=22), subclinical ketosis (SK, n=32), or were clinically normal controls (NC, n=22). The endogenous plasma metabolome was measured by chemical derivatization followed by GC/MS, which led to the detection of 267 variables. A two-sample t-test of 30, 32, and 13 metabolites showed statistically significant differences between SK and NC, CK and NC, and CK and SK, respectively. Orthogonal signal correction-partial least-square discriminant analysis (OPLS-DA) revealed that the metabolic patterns of both CK and SK were mostly similar, with the exception of a few differences. The development of CK and SK involved disturbances in many metabolic pathways, mainly including fatty acid metabolism, amino acid metabolism, glycolysis, gluconeogenesis, and the pentose phosphate pathway. A diagnostic model arbitrary two groups was constructed using OPLS-DA and receiver-operator characteristic curves (ROC). Multivariate statistical diagnostics yielded the 19 potential biomarkers for SK and NC, 31 for CK and NC, and 8 for CK and SK with area under the curve (AUC) values. Our results showed the potential biomarkers from CK, SK, and NC, including carbohydrates, fatty acids, amino acids, even sitosterol and vitamin E isomers, etc. 2-piperidinecarboxylic acid and cis-9-hexadecenoic acid were closely associated with metabolic perturbations in ketosis as Glc, BHBA and NEFA for dealing with metabolic disturbances of ketosis in clinical practice. However, further research is needed to explain changes of 2,3,4-trihydroxybutyric acid, 3,4-dihydroxybutyric acid, α-aminobutyric acid, methylmalonic acid, sitosterol and α-tocopherol in CK and SK, and to reveal differences between CK and SK. Our study shows that some new biomarkers of ketosis from plasma may find new metabolic changes to have clinically new utility and significance in diagnosis, prognosis, and prevention of ketosis in the future.
2013-01-01
Background Ketosis is an important problem for dairy cows` production performance. However, it is still little known about plasma metabolomics details of dairy ketosis. Results A gas chromatography/mass spectrometry (GC/MS) technique was used to investigate plasma metabolic differences in cows that had clinical ketosis (CK, n=22), subclinical ketosis (SK, n=32), or were clinically normal controls (NC, n=22). The endogenous plasma metabolome was measured by chemical derivatization followed by GC/MS, which led to the detection of 267 variables. A two-sample t-test of 30, 32, and 13 metabolites showed statistically significant differences between SK and NC, CK and NC, and CK and SK, respectively. Orthogonal signal correction-partial least-square discriminant analysis (OPLS-DA) revealed that the metabolic patterns of both CK and SK were mostly similar, with the exception of a few differences. The development of CK and SK involved disturbances in many metabolic pathways, mainly including fatty acid metabolism, amino acid metabolism, glycolysis, gluconeogenesis, and the pentose phosphate pathway. A diagnostic model arbitrary two groups was constructed using OPLS-DA and receiver–operator characteristic curves (ROC). Multivariate statistical diagnostics yielded the 19 potential biomarkers for SK and NC, 31 for CK and NC, and 8 for CK and SK with area under the curve (AUC) values. Our results showed the potential biomarkers from CK, SK, and NC, including carbohydrates, fatty acids, amino acids, even sitosterol and vitamin E isomers, etc. 2-piperidinecarboxylic acid and cis-9-hexadecenoic acid were closely associated with metabolic perturbations in ketosis as Glc, BHBA and NEFA for dealing with metabolic disturbances of ketosis in clinical practice. However, further research is needed to explain changes of 2,3,4-trihydroxybutyric acid, 3,4-dihydroxybutyric acid, α-aminobutyric acid, methylmalonic acid, sitosterol and α-tocopherol in CK and SK, and to reveal differences between CK and SK. Conclusion Our study shows that some new biomarkers of ketosis from plasma may find new metabolic changes to have clinically new utility and significance in diagnosis, prognosis, and prevention of ketosis in the future. PMID:24070026
Wilson, Parker C.; Fitzgibbon, Wayne R.; Garrett, Sara M.; Jaffa, Ayad A.; Luttrell, Louis M.; Brands, Michael W.
2015-01-01
Angiotensin II (AngII) plays a critical role in the regulation of vascular tone and blood pressure mainly via regulation of Ca2+ mobilization. Several reports have implicated sphingosine kinase 1 (SK1)/sphingosine 1-phosphate (S1P) in the mobilization of intracellular Ca2+ through a yet-undefined mechanism. Here we demonstrate that AngII-induces biphasic calcium entry in vascular smooth muscle cells, consisting of an immediate peak due to inositol tris-phosphate-dependent release of intracellular calcium, followed by a sustained transmembrane Ca2+ influx through store-operated calcium channels (SOCs). Inhibition of SK1 attenuates the second phase of transmembrane Ca2+ influx, suggesting a role for SK1 in AngII-dependent activation of SOC. Intracellular S1P triggers SOC-dependent Ca2+ influx independent of S1P receptors, whereas external application of S1P stimulated S1P receptor-dependent Ca2+ influx that is insensitive to inhibitors of SOCs, suggesting that the SK1/S1P axis regulates store-operated calcium entry via intracellular rather than extracellular actions. Genetic deletion of SK1 significantly inhibits both the acute hypertensive response to AngII in anaesthetized SK1 knockout mice and the sustained hypertensive response to continuous infusion of AngII in conscious animals. Collectively these data implicate SK1 as the missing link that connects the angiotensin AT1A receptor to transmembrane Ca2+ influx and identify SOCs as a potential intracellular target for SK1. PMID:25871850
Older Workers in the 21st Century: Active and Educated, a Case Study.
ERIC Educational Resources Information Center
Besl, John R.; Kale, Balkrishna D.
1996-01-01
A case study of the Wisconsin labor market suggests that in future older adults will have higher educational attainment and labor force participation rates than today's older cohorts. Changes in retirement programs and greater growth in white-collar occupations and women's employment are some of the causal factors. (SK)
Factors Distinguishing Exceptional Performance on the Uniform CPA Exam.
ERIC Educational Resources Information Center
Ashbaugh, Donald L.; Thompson, A. Frank
1993-01-01
Analysis of data from 234 Certified Public Accountant (CPA) candidates (98 of whom failed at least 1 part of the exam) showed that higher grades in the CPA review course correlated with passing the first time. Higher high school class rank and larger high school class size influenced exceptional test performance. (SK)
The Workplace and Mental Health.
ERIC Educational Resources Information Center
Pierre, Karin Domnick
1986-01-01
Findings of the Canadian Mental Health and the Workplace Project are that (1) the quality of interpersonal relations in the workplace is a major factor in emotional well-being and (2) work must be balanced with other parts of one's life. These findings imply the need for social support networks and alternative work patterns. (SK)
Employee Deviance: A Response to the Perceived Quality of the Work Experience.
ERIC Educational Resources Information Center
Hollinger, Richard; Clark, John
1982-01-01
Studies of deviant behavior in the work setting have assumed that an important factor is the employee's perception of the quality of the work experience. This study shows that measures of job satisfaction are significantly related to reported involvement in both property and production deviance in the workplace. (Author/SK)
ERIC Educational Resources Information Center
Fagenson, Ellen A.
1992-01-01
Responses from 46 proteges (46 percent of sample) and 54 nonproteges (54 percent) in high technology service companies revealed that proteges have significantly higher needs for power and achievement. No differences appeared in need for autonomy or affiliation. Proteges' gender was not a significant factor. (SK)
Predictors of Home Radon Testing and Implications for Testing Promotion Programs.
ERIC Educational Resources Information Center
Sandman, Peter M.; Weinstein, Neil D.
1993-01-01
Analysis of 4 New Jersey studies of 3,329 homeowners found that (1) thinking about radon testing is predicted by general radon knowledge; (2) decision to test is related to perceived likelihood of risk; and (3) actual testing is influenced by situational factors such as locating and choosing test kits. (SK)
Explaining Changes in Mothers' Job Satisfaction Following Childbirth.
ERIC Educational Resources Information Center
Holtzman, Mellisa; Glass, Jennifer
1999-01-01
Pregnant women (n=227) interviewed before and six and 12 months after childbirth reported declines in job satisfaction following birth. The following factors positively or negatively affected satisfaction: length of leave, ability to work at home, 30 to 35-hour work week, evening/rotating shifts, supervisor support, and child-care environment. (SK)
Project Healthy Bones: An Osteoporosis Prevention Program for Older Adults.
ERIC Educational Resources Information Center
Klotzbach-Shimomura, Kathleen
2001-01-01
Project Healthy Bones is a 24-week exercise and education program for older women and men at risk for or who have osteoporosis. The exercise component is designed to improve strength, balance, and flexibility. The education curriculum stresses the importance of exercise, nutrition, safety, drug therapy, and lifestyle factors. (SK)
ERIC Educational Resources Information Center
Kelley, Mary Lou; MacLean, Michael J.
1997-01-01
A case study of professional continuing education in palliative care delivered in rural northern Canada identified these effectiveness factors: interdisciplinary and participatory approach, responsiveness to rural health practitioners' practice context and work style, and integration of educational approaches with rural realities. (SK)
Selective Mycobacterium tuberculosis Shikimate Kinase Inhibitors as Potential Antibacterials
Gordon, Sara; Simithy, Johayra; Goodwin, Douglas C; Calderón, Angela I
2015-01-01
Owing to the persistence of tuberculosis (TB) as well as the emergence of multidrug-resistant and extensively drug-resistant (XDR) forms of the disease, the development of new antitubercular drugs is crucial. Developing inhibitors of shikimate kinase (SK) in the shikimate pathway will provide a selective target for antitubercular agents. Many studies have used in silico technology to identify compounds that are anticipated to interact with and inhibit SK. To a much more limited extent, SK inhibition has been evaluated by in vitro methods with purified enzyme. Currently, there are no data on in vivo activity of Mycobacterium tuberculosis shikimate kinase (MtSK) inhibitors available in the literature. In this review, we present a summary of the progress of SK inhibitor discovery and evaluation with particular attention toward development of new antitubercular agents. PMID:25861218
Secretion of wound healing mediators by single and bi-layer skin substitutes.
Maarof, Manira; Law, Jia Xian; Chowdhury, Shiplu Roy; Khairoji, Khairul Anuar; Saim, Aminuddin Bin; Idrus, Ruszymah Bt Hj
2016-10-01
Limitations of current treatments for skin loss caused by major injuries leads to the use of skin substitutes. It is assumed that secretion of wound healing mediators by these skin substitutes plays a role in treating skin loss. In our previous study, single layer keratinocytes (SK), single layer fibroblast (SF) and bilayer (BL; containing keratinocytes and fibroblasts layers) skin substitutes were fabricated using fibrin that had shown potential to heal wounds in preclinical studies. This study aimed to quantify the secretion of wound healing mediators, and compare between single and bi-layer skin substitutes. Skin samples were digested to harvest fibroblasts and keratinocytes, and expanded to obtain sufficient cells for the construction of skin substitutes. Acellular fibrin (AF) construct was used as control. Substitutes i.e. AF, SK, SF and BL were cultured for 2 days, and culture supernatant was collected to analyze secretion of wound healing mediators via multiplex ELISA. Among 19 wound healing mediators tested, BL substitute secreted significantly higher amounts of CXCL1 and GCSF compared to SF and AF substitute but this was not significant with respect to SK substitute. The BL substitute also secreted significantly higher amounts of CXCL5 and IL-6 compared to other substitutes. In contrast, the SK substitute secreted significantly higher amounts of VCAM-1 compared to other substitutes. However, all three skin substitutes also secreted CCL2, CCL5, CCL11, GM-CSF, IL8, IL-1α, TNF-α, ICAM-1, FGF-β, TGF-β, HGF, VEGF-α and PDGF-BB factors, but no significant difference was seen. Secretion of these mediators after transplantation may play a significant role in promoting wound healing process for the treatment of skin loss.
van Rooyen, Beverley A; Schäfer, Georgia; Leaner, Virna D; Parker, M Iqbal
2013-10-03
Recent studies have revealed that interactions between tumour cells and the surrounding stroma play an important role in facilitating tumour growth and invasion. Stromal fibroblasts produce most of the extracellular matrix components found in the stroma. The aim of this study was to investigate mechanisms involved in tumour cell-mediated regulation of extracellular matrix and adhesion molecules in co-cultured fibroblasts. To this end, microarray analysis was performed on CCD-1068SK human fibroblast cells after direct co-culture with MDA-MB-231 human breast tumour cells. We found that the expression of both connective tissue growth factor (CTGF/CCN2) and type I collagen was negatively regulated in CCD-1068SK fibroblast cells under direct co-culture conditions. Further analysis revealed that Smad7, a known negative regulator of the Smad signalling pathway involved in CCN2 promoter regulation, was increased in directly co-cultured fibroblasts. Inhibition of Smad7 expression in CCD-1068SK fibroblasts resulted in increased CCN2 expression, while Smad7 overexpression had the opposite effect. Silencing CCN2 gene expression in fibroblasts led, in turn, to a decrease in type I collagen mRNA and protein levels. ERK signalling was also shown to be impaired in CCD-1068SK fibroblasts after direct co-culture with MDA-MB-231 tumour cells, with Smad7 overexpression in fibroblasts leading to a similar decrease in ERK activity. These effects were not, however, seen in fibroblasts that were indirectly co-cultured with tumour cells. We therefore conclude that breast cancer cells require close contact with fibroblasts in order to upregulate Smad7 which, in turn, leads to decreased ERK signalling resulting in diminished expression of the stromal proteins CCN2 and type I collagen.
Chorfa, Areski; Bétemps, Dominique; Morignat, Eric; Lazizzera, Corinne; Hogeveen, Kevin; Andrieu, Thibault; Baron, Thierry
2013-06-01
Epidemiological studies indicate a role of genetic and environmental factors in Parkinson's disease involving alterations of the neuronal α-synuclein (α-syn) protein. In particular, a relationship between Parkinson's disease and occupational exposure to pesticides has been repeatedly suggested. Our objective was to precisely assess changes in α-syn levels in human neuroblastoma (SH-SY5Y) and melanoma (SK-MEL-2) cell lines following acute exposure to pesticides (rotenone, paraquat, maneb, and glyphosate) using Western blot and flow cytometry. These human cell lines express α-syn endogenously, and overexpression of α-syn (wild type or mutated A53T) can be obtained following recombinant adenoviral transduction. We found that endogenous α-syn levels in the SH-SY5Y neuroblastoma cell line were markedly increased by paraquat, and to a lesser extent by rotenone and maneb, but not by glyphosate. Rotenone also clearly increased endogenous α-syn levels in the SK-MEL-2 melanoma cell line. In the SH-SY5Y cell line, similar differences were observed in the α-syn adenovirus-transduced cells, with a higher increase of the A53T mutated protein. Paraquat markedly increased α-syn in the SK-MEL-2 adenovirus-transduced cell line, similarly for the wild-type or A53T proteins. The observed differences in the propensities of pesticides to increase α-syn levels are in agreement with numerous reports that indicate a potential role of exposure to certain pesticides in the development of Parkinson's disease. Our data support the hypothesis that pesticides can trigger some molecular events involved in this disease and also in malignant melanoma that consistently shows a significant but still unexplained association with Parkinson's disease.
Bittner, Thomas; Nadler, Sabine; Schulze, Eija; Fischer-Iglesias, Christiane
2015-10-13
Glycogen Synthase Kinase 3/SHAGGY-like kinases (GSKs) are multifunctional non-receptor ser/thr kinases. Plant GSKs are involved in hormonal signaling networks and are required for growth, development, light as well as stress responses. So far, most studies have been carried out on Arabidopsis or on other eudicotyledon GSKs. Here, we evaluated the role of TaSK1 and TaSK2, two homolog wheat (Triticum aestivum) GSKs, in brassinosteroid signaling. We explored in addition the physiological effects of brassinosteroids on wheat growth and development. A bin2-1 like gain-of-function mutation has been inserted respectively in one of the homoeologous gene copies of TaSK1 (TaSK1-A.2-1) and in one of the homoeologous gene copies of TaSK2 (TaSK2-A.2-1). Arabidopsis plants were transformed with these mutated gene copies. Severe dwarf phenotypes were obtained closely resembling those of Arabidopsis bin2-1 lines and Arabidopsis BR-deficient or BR-signaling mutants. Expression of BR downstream genes, SAUR-AC1, CPD and BAS1 was deregulated in TaSK1.2-1 and TaSK2.2-1 transgenic lines. Severe dwarf lines were partially rescued by Bikinin beforehand shown to inhibit TaSK kinase activity. This rescue was accompanied with changes in BR downstream gene expression levels. Wheat embryos and seedlings were treated with compounds interfering with BR signaling or modifying BR levels to gain insight into the role of brassinosteroids in wheat development. Embryonic axis and scutellum differentiation were impaired, and seedling growth responses were affected when embryos were treated with Epibrassinolides, Propiconazole, and Bikinin. In view of our findings, TaSKs are proposed to be involved in BR signaling and to be orthologous of Arabidopsis Clade II GSK3/SHAGGY-like kinases. Observed effects of Epibrassinolide, Propiconazole and Bikinin treatments on wheat embryos and seedlings indicate a role for BR signaling in embryonic patterning and seedling growth.
ERIC Educational Resources Information Center
Neal, Joan; Echternacht, Lonnie
1995-01-01
Experimental groups used four decision-making techniques--reverse brainstorming (RS), dialectical inquiry (DI), devil's advocacy (DA), and consensus--in evaluating writing assignments. Control group produced a better quality document. Student reaction to negative features of RS, DI, and DA were not significant. (SK)
Labour Force Participation Rates of Older Persons: An International Comparison.
ERIC Educational Resources Information Center
Clark, Robert L.; Anker, Richard
1990-01-01
Using data from 151 countries, labor force participation of older men and women was analyzed and related to economic, demographic, and policy variables. Reduced participation rates are related to increased income levels, structural changes, social security programs, and, for men, the ratio of older persons to persons of standard working age. (SK)
ERIC Educational Resources Information Center
Bacharach, Samuel; Bamberger, Peter
1992-01-01
Survey data from 215 nurses (10 male) and 430 civil engineers (10 female) supported the plausibility of occupation-specific models (positing direct paths between role stressors, antecedents, and consequences) compared to generic models. A weakness of generic models is the tendency to ignore differences in occupational structure and culture. (SK)
Efficient and high yield isolation of myoblasts from skeletal muscle.
Shahini, Aref; Vydiam, Kalyan; Choudhury, Debanik; Rajabian, Nika; Nguyen, Thy; Lei, Pedro; Andreadis, Stelios T
2018-05-24
Skeletal muscle (SkM) regeneration relies on the activity of myogenic progenitors that reside beneath the basal lamina of myofibers. Here, we describe a protocol for the isolation of the SkM progenitors from young and old mice by exploiting their outgrowth potential from SkM explants on matrigel coated dishes in the presence of high serum, chicken embryo extract and basic fibroblast growth factor. Compared to other protocols, this method yields a higher number of myoblasts (10-20 million) by enabling the outgrowth of these cells from tissue fragments. The majority of outgrowth cells (~90%) were positive for myogenic markers such as α7-integrin, MyoD, and Desmin. The myogenic cell population could be purified to 98% with one round of pre-plating on collagen coated dishes, where differential attachment of fibroblasts and other non-myogenic progenitors separates them from myoblasts. Moreover, the combination of high serum medium and matrigel coating provided a proliferation advantage to myogenic cells, which expanded rapidly (~24 h population doubling), while non-myogenic cells diminished over time, thereby eliminating the need for further purification steps such as FACS sorting. Finally, myogenic progenitors gave rise to multinucleated myotubes that exhibited sarcomeres and spontaneous beating in the culture dish. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.
Park, Hye-Jin; Cho, Jun-Hyo; Hong, Shin-Hyub; Kim, Dong-Hee; Jung, Hee-Young; Kang, In-Kyu; Cho, Young-Je
2018-01-01
Ferulic acid isolated from Tetragonia tetragonioides was tested for its whitening effect on the B16F10 mouse melanoma cell line and its anti-wrinkle activity on the CCD-986sk human dermal fibroblast cell line. Ferulic acid, one of the primary phenolic compounds that can be isolated from T. tetragonioides, has been reported to show potential as a functional food, for its whitening effect and anti-wrinkle activity. To measure its whitening and anti-wrinkle activities, cells were treated with ferulic acid isolated from T. tetragonioides at concentrations between 5 and 20 μM. Ferulic acid showed no cytotoxicity at concentrations up to 20 μM. Ferulic acid inhibited melanin synthesis, tyrosinase expression, and microphthalmia transcription factor expression in B16F10 cells stimulated with α-melanocyte stimulating hormone. Ferulic acid induced procollagen synthesis, hyaluronic acid synthesis, tissue inhibitor of metalloproteinase synthesis, and inhibited matrix metalloproteinase (MMP)-1 and MMP-9 expression in CCD-986sk cells stimulated with UV-B. On the basis of these results, we conclude that ferulic acid isolated from T. tetragonioides shows potential for use as a functional food, with whitening and anti-wrinkle activities.
Persson, Andrea; Tykesson, Emil; Westergren-Thorsson, Gunilla; Malmström, Anders; Ellervik, Ulf; Mani, Katrin
2016-07-08
We previously reported that the xyloside 2-(6-hydroxynaphthyl) β-d-xylopyranoside (XylNapOH), in contrast to 2-naphthyl β-d-xylopyranoside (XylNap), specifically reduces tumor growth both in vitro and in vivo Although there are indications that this could be mediated by the xyloside-primed glycosaminoglycans (GAGs) and that these differ in composition depending on xyloside and cell type, detailed knowledge regarding a structure-function relationship is lacking. In this study we isolated XylNapOH- and XylNap-primed GAGs from a breast carcinoma cell line, HCC70, and a breast fibroblast cell line, CCD-1095Sk, and demonstrated that both XylNapOH- and XylNap-primed chondroitin sulfate/dermatan sulfate GAGs derived from HCC70 cells had a cytotoxic effect on HCC70 cells and CCD-1095Sk cells. The cytotoxic effect appeared to be mediated by induction of apoptosis and was inhibited in a concentration-dependent manner by the XylNap-primed heparan sulfate GAGs. In contrast, neither the chondroitin sulfate/dermatan sulfate nor the heparan sulfate derived from CCD-1095Sk cells primed on XylNapOH or XylNap had any effect on the growth of HCC70 cells or CCD-105Sk cells. These observations were related to the disaccharide composition of the XylNapOH- and XylNap-primed GAGs, which differed between the two cell lines but was similar when the GAGs were derived from the same cell line. To our knowledge this is the first report on cytotoxic effects mediated by chondroitin sulfate/dermatan sulfate. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
Myosin Light Chain Kinase and the Role of Myosin Light Chain Phosphorylation in Skeletal Muscle
Stull, James T.; Kamm, Kristine E.; Vandenboom, Rene
2011-01-01
Skeletal muscle myosin light chain kinase (skMLCK) is a dedicated Ca2+/calmodulin-dependent serine-threonine protein kinase that phosphorylates the regulatory light chain (RLC) of sarcomeric myosin. It is expressed from the MYLK2 gene specifically in skeletal muscle fibers with most abundance in fast contracting muscles. Biochemically, activation occurs with Ca2+ binding to calmodulin forming a (Ca2+)4•calmodulin complex sufficient for activation with a diffusion limited, stoichiometic binding and displacement of a regulatory segment from skMLCK catalytic core. The N-terminal sequence of RLC then extends through the exposed catalytic cleft for Ser15 phosphorylation. Removal of Ca2+ results in the slow dissociation of calmodulin and inactivation of skMLCK. Combined biochemical properties provide unique features for the physiological responsiveness of RLC phosphorylation, including (1) rapid activation of MLCK by Ca2+/calmodulin, (2) limiting kinase activity so phosphorylation is slower than contraction, (3) slow MLCK inactivation after relaxation and (4) much greater kinase activity relative to myosin light chain phosphatase (MLCP). SkMLCK phosphorylation of myosin RLC modulates mechanical aspects of vertebrate skeletal muscle function. In permeabilized skeletal muscle fibers, phosphorylation-mediated alterations in myosin structure increase the rate of force-generation by myosin cross bridges to increase Ca2+-sensitivity of the contractile apparatus. Stimulation-induced increases in RLC phosphorylation in intact muscle produces isometric and concentric force potentiation to enhance dynamic aspects of muscle work and power in unfatigued or fatigued muscle. Moreover, RLC phosphorylation-mediated enhancements may interact with neural strategies for human skeletal muscle activation to ameliorate either central or peripheral aspects of fatigue. PMID:21284933
2005 Service Academies: Sexual Assault Survey: Administration, Datasets and Codebook
2005-10-01
sex w/you-Uned 326 SB026SK* [26sk] Situation w/ greatest eff -Skip 204 SB027* 27. [27---] In which semester did this occur 205 SB027U* [27...Tab recode SB038CR: Commis Officer COC 669 SB038CU* [38c] Retal by officer in chain o c-Uned 370 SB038D* 38d. [38d] Retal by other academy...sex w/you 203 SB026SK [26sk] Situation w/ greatest eff -Skip 204 SB027 27. [27---] In which semester did this occur 205 SB028 28. [28---] Where
Ting, S T L; Earley, B; Crowe, M A
2003-05-01
To determine the effect of repeated ketoprofen (K) administration to surgically castrated bulls on cortisol, acute-phase proteins, immune function, feed intake, growth and behavior, 50 Holstein x Friesian bulls (11 mo old; 300 +/- 3.3 kg) were assigned to one of five treatments: 1) untreated control (C); 2) surgical castration at 0 min (S); 3) S following an i.v. injection of 3 mg/kg of BW of K at -20 min (SK1); 4) S following 1.5 mg/kg of BW of K at -20 and 0 min (SK2); or 5) S following 1.5 mg/kg of BW of K at -20 and 0 min and 3 mg/kg of BW of K at 24 h (SK3). Castration acutely increased plasma cortisol concentrations in S- and K-treated animals compared with C, with no differences in peak and interval to peak cortisol responses among the castration groups. Overall, the integrated cortisol response was greater (P < 0.05) in the castrates than in C, whereas K treatments decreased (P < 0.05) this response compared with S alone, with no differences between K treatments. Plasma haptoglobin and fibrinogen concentrations were increased (P < 0.05) on d 3 in the castration groups compared with C as the result of tissue trauma induced by castration, whereas SK1 and SK2 had lower (P < 0.05) haptoglobin concentrations than S animals. On d 1, concanavalin A-induced interferon-gamma production was suppressed (P < 0.05) in S and SK3 compared with C, SK1, and SK2 animals. Overall from d 1 to 33, DMI were lower (P < 0.05) in S, SK1, and SK3 than in C animals. From d -1 to 35, ADG were lower (P < 0.05) in S, SK2, and SK3 compared with C animals. A higher (P < 0.05) incidence of standing postures and lower incidence of lying postures was observed in S compared with C during the first 6 h after treatment. However, the higher (P = 0.02) incidence of abnormal standing activities observed for S was reversed (P < 0.05) by the K treatments. In conclusion, surgical castration increased plasma cortisol and acute-phase proteins and decreased immune function, feed intake, and growth rate. Ketoprofen effectively reduced the cortisol response to castration, but there was no advantage in treating with two split doses of K (1.5 mg/kg of BW per dose). A repeated K dose 24 h after treatment (3 mg/kg of BW) had no influence on changes in acute-phase proteins and immune response. Systemic analgesia with K is an effective method for alleviating acute inflammatory stress associated with castration.
MacLeod, J M; Cojocaru, C V; Ratto, F; Harnagea, C; Bernardi, A; Alonso, M I; Rosei, F
2012-02-17
The combination of nanostenciling with pulsed laser deposition (PLD) provides a flexible, fast approach for patterning the growth of Ge on Si. Within each stencilled site, the morphological evolution of the Ge structures with deposition follows a modified Stranski-Krastanov (SK) growth mode. By systematically varying the PLD parameters (laser repetition rate and number of pulses) on two different substrate orientations (111 and 100), we have observed corresponding changes in growth morphology, strain and elemental composition using scanning electron microscopy, atomic force microscopy and μ-Raman spectroscopy. The growth behaviour is well predicted within a classical SK scheme, although the Si(100) growth exhibits significant relaxation and ripening with increasing coverage. Other novel aspects of the growth include the increased thickness of the wetting layer and the kinetic control of Si/Ge intermixing via the PLD repetition rate.
Kumar, Ashwani; Khan, Inshad Ali; Koul, Surrinder; Koul, Jawahir Lal; Taneja, Subhash Chandra; Ali, Intzar; Ali, Furqan; Sharma, Sandeep; Mirza, Zahid Mehmood; Kumar, Manoj; Sangwan, Pyare Lal; Gupta, Pankaj; Thota, Niranjan; Qazi, Ghulam Nabi
2008-06-01
Evaluation of novel synthetic analogues of piperine as inhibitors of multidrug efflux pump NorA of Staphylococcus aureus. A library of piperine-derived compounds was evaluated for their potential to inhibit ethidium bromide efflux in NorA-overexpressing S. aureus SA 1199B. The active compounds were then individually combined with ciprofloxacin to study the potentiation of ciprofloxacin's activity. Based on the efflux inhibition assay, a library of 200 compounds was screened. Three piperine analogues, namely SK-20, SK-56 and SK-29, were found to be the most potent inhibitors of the NorA efflux pump. These inhibitors acted in a synergistic manner with ciprofloxacin, by substantially increasing its activity against both NorA-overexpressing and wild-type S. aureus isolates. These analogues were 2- to 4-fold more potent than piperine at a significantly lower minimal effective concentration. Furthermore, these inhibitors also significantly suppressed the in vitro emergence of ciprofloxacin-resistant S. aureus. A newly identified class of compounds derived from a natural amide, piperine, is more potent than the parent molecule in potentiating the activity of ciprofloxacin through the inhibition of the NorA efflux pump. These molecules may prove useful in augmenting the antibacterial activities of fluoroquinolones in a clinical setting.
Cytoarchitecture of Zika virus infection in human neuroblastoma and Aedes albopictus cell lines
DOE Office of Scientific and Technical Information (OSTI.GOV)
Offerdahl, Danielle K.
The Zika virus (ZIKV) pandemic is a global concern due to its role in the development of congenital anomalies of the central nervous system. This mosquito-borne flavivirus alternates between mammalian and mosquito hosts, but information about the biogenesis of ZIKV is limited. Using a human neuroblastoma cell line (SK-N-SH) and an Aedes albopictus mosquito cell line (C6/36), we characterized ZIKV infection by immunofluorescence, transmission electron microscopy (TEM), and electron tomography (ET) to better understand infection in these disparate host cells. ZIKV replicated well in both cell lines, but infected SK-N-SH cells suffered a lytic crisis. Flaviviruses scavenge host cell membranesmore » to serve as replication platforms and ZIKV showed the hallmarks of this process. Via TEM, we identified virus particles and 60–100 nm spherular vesicles. ET revealed these vesicular replication compartments contain smaller 20–30 nm spherular structures. Our studies indicate that SK-N-SH and C6/36 cells are relevant models for viral cytoarchitecture study. - Highlights: •First electron tomography of Zika virus cytoarchitecture. •Comparison of Zika virus infection in human neuroblastoma and mosquito cells. •Ultrastructure of Zika virus infection in human neuroblastoma and mosquito cells.« less
Is ciprofloxacin safe in patients with solitary kidney and upper urinary tract infection?
Gluhovschi, Gheorghe; Gadalean, Florica; Gluhovschi, Cristina; Velciov, Silvia; Petrica, Ligia; Bob, Flaviu; Bozdog, Gheorghe; Kaycsa, Adriana
2016-12-01
The solitary kidney (SK) undergoes adaptive phenomena of hyperfunction and hyperfiltration. These secondary adaptive phenomena can make it more vulnerable to potentially nephrotoxic therapies. Adverse reactions of the kidneys to ciprofloxacin are rare, but sometimes severe. Therefore, our study sought to assess the reactions to ciprofloxacin of patients with solitary kidney (SK) and urinary tract infection (UTI) by means of urinary biomarkers. We studied 19 patients with SK and urinary tract infection (UTI) who had been administered a 7-day treatment with intravenous ciprofloxacin. Urinary N-acetyl-beta-d-glucosaminidase, alpha 1-microglobulin, and estimated glomerular filtration rate (eGFR) of these patients were measured at the initiation and at the end of treatment. In 47.37% patients NAG diminished under ciprofloxacin treatment. This observation has the significance of favourable evolution of the tubulointerstitial lesions caused by UTI and lack of nephrotoxic effects; 52.63% cases presented an increase of urinary NAG, a fact that suggests a nephrotoxic effect of ciprofloxacin. The evolution of urinary alpha 1-microglobulin was similar to that one of urinary NAG. Only one of three cases with chronic kidney disease (CKD) stage 5 presented acute kidney injury, associated with increase in the tubular markers. In spite of the high variability of the urinary biomarkers, UTI evolved favourably in these cases; eGFR increased in 16 out of 19 patients, a fact which is indicative of a good outcome of renal function, even in patients with elevated levels of the tubular damage biomarkers. This observation supports the hypothesis that eGFR may be dissociated from the biomarkers which assess tubular injury. In SK patients the occurrence of AKI is not frequent, although the urinary biomarkers rise in some patients treated with ciprofloxacin. This is related not only to the nephrotoxic effect of the drug, but probably to the association of other factors (allergy, individual susceptibility). In SK patients, renal tubular biomarkers, especially NAG, allow monitoring of tubular injury and impose caution in prescribing ciprofloxacin treatment, mainly to patients at risk. Ciprofloxacin is relatively safe regarding its nephrotoxicity, while caution is required in vulnerable patients. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Bindon, Keren; Kassara, Stella; Hayasaka, Yoji; Schulkin, Alex; Smith, Paul
2014-11-26
To explore the effect of tannin composition on pigment formation, model ferments of purified 3-O-monoglucoside anthocyanins (ACN) were conducted either alone or in the presence of two different tannins. Tannins were isolated from grape seeds (Sd) or skins (Sk) following exhaustive extraction in 70% v/v acetone. The Sd and Sk tannin fractions had a mean degree of polymerization of 5.2 and 25.6, respectively. The Sd fraction was highly galloylated, at 22%, but galloylation was <2% in the Sk fraction. The Sk fraction was distinguished by a high proportion of prodelphinidin, at 58%. After a 6 month aging period, polymeric pigments were quantified and their color properties determined following isolation by solid-phase extraction. Wine color and polymeric pigment were highest in the treatment containing ACN+Sd and similar in the ACN+Sk and ACN treatments. The same trend between treatments was observed for total and polymeric nonbleachable pigments. Only minor changes in tannin subunit composition were found following ACN incorporation, but the size distribution of polymeric pigments determined by gel permeation chromatography decreased, in particular for the ACN+Sk treatment. Color incorporation in the higher molecular mass range was lower for ACN+Sk wines than for ACN+Sd wines. Compositional differences between the two tannin fractions may therefore limit the incorporation of ACNs in the colored form. The results suggest that in the ACN+Sk and ACN treatments, the formation of lower molecular mass oligomeric pigments was favored. In polymeric pigments derived from ACNs, the presence of ethyl- and vinyl-linked ACNs to the level of trimers was identified using mass spectrometry.
Stanhewicz, Anna E.; Proctor, David N.; Alexander, Lacy M.; Kenney, W. Larry
2015-01-01
During supine passive heating, increases in skin blood flow (SkBF) and cardiac output (Qc) are both blunted in older adults. The aim here was to determine the effect of acutely correcting the peripheral vasodilatory capacity of aged skin on the integrated cardiovascular responses to passive heating. A secondary aim was to examine the SkBF-Qc relation during hyperthermia in the presence (upright posture) and absence (dynamic exercise) of challenges to central venous pressure. We hypothesized that greater increases in SkBF would be accompanied by greater increases in Qc. Eleven healthy older adults (69 ± 3 yr) underwent supine passive heating (0.8°C rise in core temperature; water-perfused suit) after ingesting sapropterin (BH4, a nitric oxide synthase cofactor; 10 mg/kg) or placebo (randomized double-blind crossover design). Twelve young (24 ± 1 yr) subjects served as a comparison group. SkBF (laser-Doppler flowmetry) and Qc (open-circuit acetylene wash-in) were measured during supine heating, heating + upright posture, and heating + dynamic exercise. Throughout supine and upright heating, sapropterin fully restored the SkBF response of older adults to that of young adults but Qc remained blunted. During heat + upright posture, SkBF failed to decrease in untreated older subjects. There were no age- or treatment-related differences in SkBF-Qc during dynamic exercise. The principal finding of this study was that the blunted Qc response to passive heat stress is directly related to age as opposed to the blunted peripheral vasodilatory capacity of aged skin. Furthermore, peripheral impairments to SkBF in the aged may contribute to inapposite responses during challenges to central venous pressure during hyperthermia. PMID:26494450
Petrov, Anton; Perekhvatova, Natalia; Skulachev, Maxim; Stein, Linda; Ousler, George
2016-01-01
This Phase 2 clinical trial assessed the efficacy and safety of the novel antioxidative, renewable compound SkQ1 for topical treatment of dry eye signs and symptoms. In a single-center, randomized, double-masked, placebo-controlled, 29-day study, 91 subjects with mild to moderate dry eye instilled the study drug twice daily and recorded dry eye symptoms daily. Subjects were randomized 1:1:1 into one of three ophthalmic solution treatment groups: SkQ1 1.55 µg/mL, SkQ1 0.155 µg/mL, or 0.0 µg/mL (placebo). Subjects were exposed to a controlled adverse environment chamber at 3 of the 4 study visits (Day -7, Day 1, and Day 29). Investigator assessments occurred at all study visits. SkQ1 was safe and efficacious in treating dry eye signs and symptoms. Statistically significant improvements with SkQ1 compared to placebo occurred for the dry eye signs of corneal fluorescein staining and lissamine green staining in the central region and lid margin redness, and for the dry eye symptoms of ocular discomfort, dryness, and grittiness. In addition, SkQ1 demonstrated greater efficacy compared to placebo, although the differences were not statistically significant, for corneal fluorescein staining in other regions and/or time points (total staining score, central region, corneal sum score, and temporal region), lissamine green staining for the central and nasal regions, and blink rate scores. This Phase 2 study indicated that SkQ1 is safe and efficacious for the treatment of dry eye signs and symptoms and supported previous study results. Clinicaltrials.gov identifier: NCT02121301. Miotech S.A.
Liu, Yuhong; Xie, An; Singh, Arun K; Ehsan, Afshin; Choudhary, Gaurav; Dudley, Samuel; Sellke, Frank W; Feng, Jun
2015-08-24
Diabetes is associated with coronary arteriolar endothelial dysfunction. We investigated the role of the small/intermediate (SK(Ca)/IK(Ca)) conductance of calcium-activated potassium channels in diabetes-related endothelial dysfunction. Coronary arterioles (80 to 150 μm in diameter) were dissected from discarded right atrial tissues of diabetic (glycosylated hemoglobin = 9.6±0.25) and nondiabetic patients (glycosylated hemoglobin 5.4±0.12) during coronary artery bypass graft surgery (n=8/group). In-vitro relaxation response of precontracted arterioles was examined in the presence of the selective SK(Ca)/IK(Ca) activator NS309 and other vasodilatory agents. The channel density and membrane potential of diabetic and nondiabetic endothelial cells was measured by using the whole cell patch-clamp technique. The protein expression and distribution of the SK(Ca)/IK(Ca) in the human myocardium and coronary arterioles was examined by Western blotting and immunohistochemistry. Our results indicate that diabetes significantly reduced the coronary arteriolar response to the SK(Ca)/IK(Ca) activator NS309 compared to the respective responses of nondiabetic vessels (P<0.05 versus nondiabetes). The relaxation response of diabetic arterioles to NS309 was prevented by denudation of endothelium (P=0.001 versus endothelium-intact). Diabetes significantly decreased endothelial SK(Ca)/IK(Ca) currents and hyperpolarization induced by the SK(Ca)/IK(Ca) activator NS309 as compared with that of nondiabetics. There were no significant differences in the expression and distribution of SK(Ca)/IK(Ca) proteins in the coronary microvessels. Diabetes is associated with inactivation of endothelial SK(Ca)/IK(Ca) channels, which may contribute to endothelial dysfunction in diabetic patients. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.
Ren, Wei; Liu, Yuehong; Wan, Shaoheng; Fei, Chang; Wang, Wei; Chen, Yingying; Zhang, Zhihui; Wang, Ting; Wang, Jinshu; Zhou, Lan; Weng, Yaguang; He, Tongchuan; Zhang, Yan
2014-01-01
Bone morphogenetic protein 9 (BMP9), a member of TGF-β superfamily, is reported to inhibit the growth and migration of prostate cancer, osteosarcoma and triple-negative MDA-MB-231 breast cancer cells. However, little is known about the effect of on the biological behaviors of HER2-positive SK-BR-3 breast cancer cells and the underlying mechanisms. This study aimed to investigate the effects of BMP9 on the proliferation and metastasis of SK-BR-3 cells with BMP9 over-expression or BMP9 down-regulated expression. Results indicated that exogenously expressed BMP9 inhibited the proliferation and metastasis of SK-BR-3 cells while decreased endogenous BMP9 expression in SK-BR-3 cells promoted the proliferation and migration of breast cancer cells in vitro and in vivo. In SK-BR-3 cells with BMP9 over-expression, the phosphorylation of HER2, ERK1/2 and AKT was markedly suppressed and the HER2 expression decreased at both mRNA and protein levels, while opposite results were observed in SK-BR-3 cells with BMP9 knock down. When the phosphorylation of ERK1/2 and PI3K/AKT was inhibited by PD98059 and LY294002, respectively, the decreased proliferation and invasion induced by BMP9 knock down were eliminated. These findings suggest that BMP9 can inhibit the proliferation and metastasis of SK-BR-3 cells via inactivating ERK1/2 and PI3K/AKT signaling pathways. Thus, BMP9 may serve as a useful agent in the treatment of HER-2 positive breast cancer. PMID:24805814
Ren, Wei; Liu, Yuehong; Wan, Shaoheng; Fei, Chang; Wang, Wei; Chen, Yingying; Zhang, Zhihui; Wang, Ting; Wang, Jinshu; Zhou, Lan; Weng, Yaguang; He, Tongchuan; Zhang, Yan
2014-01-01
Bone morphogenetic protein 9 (BMP9), a member of TGF-β superfamily, is reported to inhibit the growth and migration of prostate cancer, osteosarcoma and triple-negative MDA-MB-231 breast cancer cells. However, little is known about the effect of on the biological behaviors of HER2-positive SK-BR-3 breast cancer cells and the underlying mechanisms. This study aimed to investigate the effects of BMP9 on the proliferation and metastasis of SK-BR-3 cells with BMP9 over-expression or BMP9 down-regulated expression. Results indicated that exogenously expressed BMP9 inhibited the proliferation and metastasis of SK-BR-3 cells while decreased endogenous BMP9 expression in SK-BR-3 cells promoted the proliferation and migration of breast cancer cells in vitro and in vivo. In SK-BR-3 cells with BMP9 over-expression, the phosphorylation of HER2, ERK1/2 and AKT was markedly suppressed and the HER2 expression decreased at both mRNA and protein levels, while opposite results were observed in SK-BR-3 cells with BMP9 knock down. When the phosphorylation of ERK1/2 and PI3K/AKT was inhibited by PD98059 and LY294002, respectively, the decreased proliferation and invasion induced by BMP9 knock down were eliminated. These findings suggest that BMP9 can inhibit the proliferation and metastasis of SK-BR-3 cells via inactivating ERK1/2 and PI3K/AKT signaling pathways. Thus, BMP9 may serve as a useful agent in the treatment of HER-2 positive breast cancer.
Tadayon, Ateke; Jamshidi, Reza; Esmaeili, Akbar
2015-11-10
Thrombolytic therapy for acute myocardial infarction standardly makes use of the medications streptokinase (SK) and tissue plasminogen activator (tPA). In this study, the potential of silica-coated magnetic nanoparticles (SiO2-MNPs) as nanocarriers clinical thrombolytic therapy was investigated. SiO2-MNPs for use in targeted therapeutic delivery of tPA and SK were prepared using a combined technique incorporating controlled precipitation and hydrothermal methods. Response surface methodology (RSM) was employed to evaluate the efficiency of the SiO2-MNPs. The production of SK secreted from Streptococcus equi was enhanced using random mutagenesis. The tPA and SK A were encapsulated by means of a silanizing agent with a surface rich in 3-aminopropyltrimethoxysilane layered around the SiO2-MNPs. Blood clot lysis assays and fibrin-containing agarose plates were used to carry out in vitro thrombolysis testing. The optimum conditions for producing MNPs were found to be at pH=13 and at a temperature of 75°C for 45 min. Culture conditions of 2.75% NaCl concentration at initial pH=7.5 for 90 s under UV resulted in maximum SK activity. The tPA/SK-conjugated SiO2-MNPs (SiO2-MNP-tPA-SK) increased operating stability in whole blood and storage stability in a buffer by 92%. More effective thrombolysis using magnetic targeting was indicated by a 38% reduction in blood clot lysis time achieved with SiO2-MNP-tPA-SK compared to administering the SiO2-MNPs without guidance. The silica-coated magnetic nanocarriers developed in this study show potential for improved clinical thrombolytic therapy. Copyright © 2015. Published by Elsevier B.V.
Polynomial interpolation and sums of powers of integers
NASA Astrophysics Data System (ADS)
Cereceda, José Luis
2017-02-01
In this note, we revisit the problem of polynomial interpolation and explicitly construct two polynomials in n of degree k + 1, Pk(n) and Qk(n), such that Pk(n) = Qk(n) = fk(n) for n = 1, 2,… , k, where fk(1), fk(2),… , fk(k) are k arbitrarily chosen (real or complex) values. Then, we focus on the case that fk(n) is given by the sum of powers of the first n positive integers Sk(n) = 1k + 2k + ṡṡṡ + nk, and show that Sk(n) admits the polynomial representations Sk(n) = Pk(n) and Sk(n) = Qk(n) for all n = 1, 2,… , and k ≥ 1, where the first representation involves the Eulerian numbers, and the second one the Stirling numbers of the second kind. Finally, we consider yet another polynomial formula for Sk(n) alternative to the well-known formula of Bernoulli.
Lupia, Enrico; Del Sorbo, Lorenzo; Bergerone, Serena; Emanuelli, Giorgio; Camussi, Giovanni; Montrucchio, Giuseppe
2003-01-01
Thrombolytic agents, used to restore blood flow to ischaemic tissues, activate several enzymatic systems with pro-inflammatory effects, thus potentially contributing to the pathogenesis of ischaemia–reperfusion injury. Platelet-activating factor (PAF), a phospholipid mediator of inflammation, has been implicated in the pathogenesis of this process. We previously showed that the infusion of streptokinase (SK) induces the intravascular release of PAF in patients with acute myocardial infarction (AMI), and that cultured human endothelial cells (EC) synthesized PAF in response to SK and plasmin (PLN). In the present study, we investigated the role of the membrane attack complex (MAC) of complement in the PLN-induced synthesis of PAF. In vivo, we showed a correlation between the levels of soluble terminal complement components (sC5b-9) and the concentrations of PAF detected in blood of patients with AMI infused with SK. In vitro both EC and polymorphonuclear neutrophils (PMN), incubated in the presence of PLN and normal human serum, showed an intense staining for the MAC neoepitope, while no staining was detected when they were incubated with PLN in the presence of heat-inactivated normal human serum. Moreover, the insertion of MAC on EC and PMN plasmamembrane elicited the synthesis of PAF. In conclusion, our results elucidate the mechanisms involved in PAF production during the activation of the fibrinolytic system, showing a role for complement products in this setting. The release of PAF may increase the inflammatory response, thus limiting the beneficial effects of thrombolytic therapy. Moreover, it may have a pathogenic role in other pathological conditions, such as transplant rejection, tumoral angiogenesis, and septic shock, where fibrinolysis is activated. PMID:12871223
Lupia, Enrico; Del Sorbo, Lorenzo; Bergerone, Serena; Emanuelli, Giorgio; Camussi, Giovanni; Montrucchio, Giuseppe
2003-08-01
Thrombolytic agents, used to restore blood flow to ischaemic tissues, activate several enzymatic systems with pro-inflammatory effects, thus potentially contributing to the pathogenesis of ischaemia-reperfusion injury. Platelet-activating factor (PAF), a phospholipid mediator of inflammation, has been implicated in the pathogenesis of this process. We previously showed that the infusion of streptokinase (SK) induces the intravascular release of PAF in patients with acute myocardial infarction (AMI), and that cultured human endothelial cells (EC) synthesized PAF in response to SK and plasmin (PLN). In the present study, we investigated the role of the membrane attack complex (MAC) of complement in the PLN-induced synthesis of PAF. In vivo, we showed a correlation between the levels of soluble terminal complement components (sC5b-9) and the concentrations of PAF detected in blood of patients with AMI infused with SK. In vitro both EC and polymorphonuclear neutrophils (PMN), incubated in the presence of PLN and normal human serum, showed an intense staining for the MAC neoepitope, while no staining was detected when they were incubated with PLN in the presence of heat-inactivated normal human serum. Moreover, the insertion of MAC on EC and PMN plasmamembrane elicited the synthesis of PAF. In conclusion, our results elucidate the mechanisms involved in PAF production during the activation of the fibrinolytic system, showing a role for complement products in this setting. The release of PAF may increase the inflammatory response, thus limiting the beneficial effects of thrombolytic therapy. Moreover, it may have a pathogenic role in other pathological conditions, such as transplant rejection, tumoral angiogenesis, and septic shock, where fibrinolysis is activated.
Authement, Michael E; Langlois, Ludovic D; Shepard, Ryan D; Browne, Caroline A; Lucki, Irwin; Kassis, Haifa; Nugent, Fereshteh S
2018-03-06
Centrally released corticotropin-releasing factor or hormone (extrahypothalamic CRF or CRH) in the brain is involved in the behavioral and emotional responses to stress. The lateral habenula (LHb) is an epithalamic brain region involved in value-based decision-making and stress evasion. Through its inhibition of dopamine-mediated reward circuitry, the increased activity of the LHb is associated with addiction, depression, schizophrenia, and behavioral disorders. We found that extrahypothalamic CRF neurotransmission increased neuronal excitability in the LHb. Through its receptor CRFR1 and subsequently protein kinase A (PKA), CRF application increased the intrinsic excitability of LHb neurons by affecting changes in small-conductance SK-type and large-conductance BK-type K + channels. CRF also reduced inhibitory γ-aminobutyric acid-containing (GABAergic) synaptic transmission onto LHb neurons through endocannabinoid-mediated retrograde signaling. Maternal deprivation is a severe early-life stress that alters CRF neural circuitry and is likewise associated with abnormal mental health later in life. LHb neurons from pups deprived of maternal care exhibited increased intrinsic excitability, reduced GABAergic transmission, decreased abundance of SK2 channel protein, and increased activity of PKA, without any substantial changes in Crh or Crhr1 expression. Furthermore, maternal deprivation blunted the response of LHb neurons to subsequent, acute CRF exposure. Activating SK channels or inhibiting postsynaptic PKA activity prevented the effects of both CRF and maternal deprivation on LHb intrinsic excitability, thus identifying potential pharmacological targets to reverse central CRF circuit dysregulation in patients with associated disorders. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.
Elmadbouh, I; Haider, Husnain Kh; Jiang, Shujia; Idris, Niagara Muhammad; Lu, Gang; Ashraf, Muhammad
2007-04-01
We aimed to optimize non-viral transfection of human stromal cell derived factor (SDF-1alpha) gene into skeletal myoblasts (SkM) and, transplant these cells to establish transient SDF-1alpha gradient to favor extra-cardiac stem cell translocation into infarcted heart. Optimized conditions for transfection of SDF-1alpha gene into syngenic SkM were achieved using FuGene6/phSDF-1alpha (3:2v/w, 4 h transfection) with 125 microM ZnCl(2) (p<0.001). After characterization for transgene overexpression by immunostaining, ELISA and PCR, the cells were transplanted in female rat model of myocardial infarction. Thirty-six rats were grouped (n=12/group) to receive 70 microl DMEM without cells (group-1) or containing 1.5 x 10(6) non-transfected (group-2) or SDF-1alpha transfected SkM (group-3). On day 4 post-transplantation (in 4 animals/group), marked expression of SDF-1alpha/sry-gene (p=0.003), total Akt, phospho-Akt and Bcl2 was observed in group-3. The number of CD31(+), C-kit(+) and CD34(+) cells was highest in group-3 hearts (p<0.01). Blood vessel density in group-3 was higher in both scar and peri-scar regions (p<0.001) as compared with other groups. Echocardiography showed improved indices of left ventricle contractile function and remodeling in group-3 (p<0.05) as compared with groups-1 and -2. We conclude that ex vivo SDF-1alpha transgene delivery promotes stem and progenitor cell migration to the heart, activates cell survival signaling and enhances angiomyogenesis in the infarcted heart.
Watanabe, Miho; Tokizawa, Riho; Kojima, Hisaya; Fukui, Manabu
2017-01-01
10.1601/nm.25721 strain skLN1 T is the type strain of the type species in the genus 10.1601/nm.25720 which is the one of the genera in the family 10.1601/nm.5070 within the phylum 10.1601/nm.3874. 10.1601/nm.25721 strain skLN1 T is a Gram-positive, spore-forming thermophilic neutrophile isolated from freshwater lake sediment. Here, we present the draft genome sequence of strain skLN1 T , which consists of 3,902,380 bp with a G + C content of 50.38%.
A Small Potassium Current in AgRP/NPY Neurons Regulates Feeding Behavior and Energy Metabolism.
He, Yanlin; Shu, Gang; Yang, Yongjie; Xu, Pingwen; Xia, Yan; Wang, Chunmei; Saito, Kenji; Hinton, Antentor; Yan, Xiaofeng; Liu, Chen; Wu, Qi; Tong, Qingchun; Xu, Yong
2016-11-08
Neurons that co-express agouti-related peptide (AgRP) and neuropeptide Y (NPY) are indispensable for normal feeding behavior. Firing activities of AgRP/NPY neurons are dynamically regulated by energy status and coordinate appropriate feeding behavior to meet nutritional demands. However, intrinsic mechanisms that regulate AgRP/NPY neural activities during the fed-to-fasted transition are not fully understood. We found that AgRP/NPY neurons in satiated mice express high levels of the small-conductance calcium-activated potassium channel 3 (SK3) and are inhibited by SK3-mediated potassium currents; on the other hand, food deprivation suppresses SK3 expression in AgRP/NPY neurons, and the decreased SK3-mediated currents contribute to fasting-induced activation of these neurons. Genetic mutation of SK3 specifically in AgRP/NPY neurons leads to increased sensitivity to diet-induced obesity, associated with chronic hyperphagia and decreased energy expenditure. Our results identify SK3 as a key intrinsic mediator that coordinates nutritional status with AgRP/NPY neural activities and animals' feeding behavior and energy metabolism. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Abe, K.; Bronner, C.; Pronost, G.; Hayato, Y.; Ikeda, M.; Iyogi, K.; Kameda, J.; Kato, Y.; Kishimoto, Y.; Marti, Ll.; Miura, M.; Moriyama, S.; Nakahata, M.; Nakano, Y.; Nakayama, S.; Okajima, Y.; Orii, A.; Sekiya, H.; Shiozawa, M.; Sonoda, Y.; Takeda, A.; Takenaka, A.; Tanaka, H.; Tasaka, S.; Tomura, T.; Akutsu, R.; Kajita, T.; Kaneyuki, K.; Nishimura, Y.; Okumura, K.; Tsui, K. M.; Labarga, L.; Fernandez, P.; Blaszczyk, F. d. M.; Gustafson, J.; Kachulis, C.; Kearns, E.; Raaf, J. L.; Stone, J. L.; Sulak, L. R.; Berkman, S.; Tobayama, S.; Goldhaber, M.; Elnimr, M.; Kropp, W. R.; Mine, S.; Locke, S.; Weatherly, P.; Smy, M. B.; Sobel, H. W.; Takhistov, V.; Ganezer, K. S.; Hill, J.; Kim, J. Y.; Lim, I. T.; Park, R. G.; Himmel, A.; Li, Z.; O'Sullivan, E.; Scholberg, K.; Walter, C. W.; Ishizuka, T.; Nakamura, T.; Jang, J. S.; Choi, K.; Learned, J. G.; Matsuno, S.; Smith, S. N.; Amey, J.; Litchfield, R. P.; Ma, W. Y.; Uchida, Y.; Wascko, M. O.; Cao, S.; Friend, M.; Hasegawa, T.; Ishida, T.; Ishii, T.; Kobayashi, T.; Nakadaira, T.; Nakamura, K.; Oyama, Y.; Sakashita, K.; Sekiguchi, T.; Tsukamoto, T.; Abe, KE.; Hasegawa, M.; Suzuki, A. T.; Takeuchi, Y.; Yano, T.; Cao, S. V.; Hayashino, T.; Hiraki, T.; Hirota, S.; Huang, K.; Jiang, M.; Minamino, A.; Nakamura, KE.; Nakaya, T.; Quilain, B.; Patel, N. D.; Wendell, R. A.; Anthony, L. H. V.; McCauley, N.; Pritchard, A.; Fukuda, Y.; Itow, Y.; Murase, M.; Muto, F.; Mijakowski, P.; Frankiewicz, K.; Jung, C. K.; Li, X.; Palomino, J. L.; Santucci, G.; Vilela, C.; Wilking, M. J.; Yanagisawa, C.; Ito, S.; Fukuda, D.; Ishino, H.; Kibayashi, A.; Koshio, Y.; Nagata, H.; Sakuda, M.; Xu, C.; Kuno, Y.; Wark, D.; Di Lodovico, F.; Richards, B.; Tacik, R.; Kim, S. B.; Cole, A.; Thompson, L.; Okazawa, H.; Choi, Y.; Ito, K.; Nishijima, K.; Koshiba, M.; Totsuka, Y.; Suda, Y.; Yokoyama, M.; Calland, R. G.; Hartz, M.; Martens, K.; Simpson, C.; Suzuki, Y.; Vagins, M. R.; Hamabe, D.; Kuze, M.; Yoshida, T.; Ishitsuka, M.; Martin, J. F.; Nantais, C. M.; Tanaka, H. A.; Konaka, A.; Chen, S.; Wan, L.; Zhang, Y.; Minamino, A.; Wilkes, R. J.; Super-Kamiokande Collaboration
2017-12-01
We present the results of a search in the Super-Kamiokande (SK) detector for excesses of neutrinos with energies above a few GeV that are in the direction of the track events reported in IceCube. Data from all SK phases (SK-I through SK-IV) were used, spanning a period from 1996 April to 2016 April and corresponding to an exposure of 225 kiloton-years. We considered the 14 IceCube track events from a data set with 1347 livetime days taken from 2010 to 2014. We use Poisson counting to determine if there is an excess of neutrinos detected in SK in a 10° search cone (5° for the highest energy data set) around the reconstructed direction of the IceCube event. No significant excess was found in any of the search directions we examined. We also looked for coincidences with a recently reported IceCube multiplet event. No events were detected within a ±500 s time window around the first detected event, and no significant excess was seen from that direction over the lifetime of SK.
ERIC Educational Resources Information Center
Menon, Maria E.; Christou, Constantinos
2002-01-01
Factor analysis of data from 66 inservice and 79 preservice elementary teachers in Cyprus revealed that future teachers had lower satisfaction with the headmaster's role, school organization, and school climate. Satisfaction with teacher incentives and work conditions was lower for inservice teachers. (Contains 20 references.) (SK)
ERIC Educational Resources Information Center
McCuaig, Shauna; And Others
1996-01-01
Responses from 38 of 184 retailing graduates, 24 of 111 recruiters in the apparel field, 58 of 200 retail merchandising educators, and 45 of 47 current students found that differences in their ratings of the importance of 53 competencies for entry workers centered on three factors: merchandising, leadership, and monitoring. (SK)
Mammographic Breast Density in a Cohort of Medically Underserved Women
2013-10-01
94http : / / www.elsev ier .com/ locate / jeghPerinatal factors and breast cancer risk among HispanicsMaureen Sanderson a,b,*, Adriana Pérez c,d, Mirabel...risk of breast cancer: a systematic review and meta-analysis of current evidence. Lancet Oncol 2007;8:1088–100. [3] Park SK, Kang D, McGlynn KA
17 CFR 229.904 - (Item 904) Risk factors and other considerations.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 1934 AND ENERGY POLICY AND CONSERVATION ACT OF 1975-REGULATION S-K Roll-Up Transactions § 229.904 (Item... successor received by investors in the roll-up transaction will trade in the securities markets at a price... assets of the successor, and the effects on investors of such a trading market discount. (b) Quantify...
[Roles of Y box-binding protein 1 in SK-BR-3 breast cancer proliferation].
Shi, Jianhong; Lü, Xinrui; Wang, Bing; Daudan, Lin; Yanan, Wang; Yuhui, Bu; Zhenfeng, Ma
2014-09-30
To explore the roles of Y box-binding protein 1 (YB-1) in breast cancer cell proliferation. Twenty cases of surgical removal of breast cancer tissue (diagnosed with invasive ductal carcinoma, stage II, by postoperative paraffin pathology) and normal breast tissues adjacent to carcinoma were collected during June 2013 to August 2013.Quantitative real-time PCR (qRT-PCR) was performed to detect the YB1 mRNA levels. Cultured mammary epithelial cells (HBL-100) and breast cancer cells (MCF7, MDA-MB-231 & SK-BR-3 cells) were harvested and qRT-PCR was performed to detect the YB1 mRNA levels.SK-BR-3 cells were stimulated with various concentrations of PDGF-BB and YB1 expression levels were detected by qRT-PCR. Down-regulation or over-expression of YB1 by si-YB1 or Ad-GFP-YB1 was detected in SK-BR-3 cells. And MTS cell proliferation assay kit was used to detect cell proliferation. YB1 mRNA levels were significantly higher in breast cancer tissues and MDA-MB-231 and SK-BR-3 breast cancer cell lines than that in adjacent normal breast tissues and HBL-100 mammary epithelial cells respectively (P < 0.05).YB1 expression levels increased in PDGF-BB stimulated SK-BR-3 cells in a dose-dependent manner. A down-regulation of endogenous YB1 decreases and an over-expression of exogenous YB1 promotes the proliferation activity in SK-BR-3 cells.
Woodward, Kirsty A.; Unnithan, Vish; Hopkins, Nicola D.
2015-01-01
Context Kinesiology tape (KT) has become popular among athletes for both injury prevention and rehabilitation due to its reported therapeutic effects, including facilitation of lymphatic flow and enhanced peripheral blood flow. However, evidence to support such claims is insufficient. Objective To determine whether KT improves skin blood flow (SkBF) responses in young, elite soccer players. Design Randomized crossover study. Setting Research laboratory. Patients or Other Participants Thirteen healthy, elite, adolescent male soccer players (age = 14.7 ± 0.6 years). Intervention(s) Participants completed 2 experimental trials; during trial 1, the volar aspect of the dominant forearm was taped. Forearm SkBF was measured within the taped area and 3 cm lateral to the taped area. During trial 2, no tape was applied to either site. Both trials were performed within 7 days. Main Outcome Measure(s) Baseline and maximal thermally (42°C) stimulated SkBF responses were assessed using laser Doppler flowmetry. Continuously measured SkBF and derived mean arterial pressure obtained at 5-minute intervals were used to calculate cutaneous vascular conductance (CVC), the primary outcome measure. Results No differences were observed for baseline SkBF or CVC between trials or measurement sites. After local heating, no differences were evident for SkBF or CVC between trials or measurement sites. Conclusions Our findings suggest that, in healthy, trained adolescent males, KT was not associated with increased forearm SkBF. PMID:26445024
Assiri, Abdullah S; El-Gamal, Basiouny A; Hafez, Elsayed E; Haidara, Mohamed A
2014-12-01
To produce an effective recombinant streptokinase (rSK) from pathogenic Streptococcus pyogenes isolate in yeast, and evaluate its potential for thrombolytic therapy. This study was conducted from November 2012 to December 2013 at King Khalid University, Abha, Kingdom of Saudi Arabia (KSA). Throat swabs collected from 45 pharyngitis patients in Asser Central Hospital, Abha, KSA were used to isolate Streptococcus pyogenes. The bacterial DNA was used for amplification of the streptokinase gene (1200 bp). The gene was cloned and in vitro transcribed in an eukaryotic expression vector that was transformed into yeast Pichia pastoris SMD1168, and the rSK protein was purified and tested for its thrombolytic activity. The Streptococcus pyogenes strain was isolated and its DNA nucleotide sequence revealed similarity to other Streptococcus pyogenes in the Gene bank. Sequencing of the amplified gene based on DNA nucleotide sequence revealed a SK gene closely related to other SK genes in the Gene bank. However, based on deduced amino acids sequence, the gene formed a separate cluster different from clusters formed by other examined genes, suggesting a new bacterial isolate and accordingly a new gene. The purified protein showed 82% clot lysis compared to a commercial SK (81%) at an enzyme concentration of 2000 U/ml. The present yeast rSK showed similar thrombolytic activity in vitro as that of a commercial SK, suggesting its potential for thrombolytic therapy and large scale production.
Improving cardiac conduction with a skeletal muscle sodium channel by gene and cell therapy
Lu, Jia; Wang, Hong-Zhan; Jia, Zhiheng; Zuckerman, Joan; Lu, Zhongju; Guo, Yuanjian; Boink, Gerard J.J.; Brink, Peter R.; Robinson, Richard B.; Entcheva, Emilia; Cohen, Ira S.
2012-01-01
The voltage-gated Na+ channel is a critical determinant of the action potential upstroke. Increasing Na+ conductance may speed action potential propagation. Here we propose use of the skeletal muscle Na+ channel SkM1 as a more favorable gene than the cardiac isoform SCN5A to enhance conduction velocity in depolarized cardiac tissue. We used cells which electrically coupled with cardiac myocytes as a delivery platform to introduce the Na+ channels. HEK293 cells were stably transfected with SkM1 or SCN5A. SkM1 had a more depolarized (18mV shift) inactivation curve than SCN5A. We also found that SkM1 recovered faster from inactivation than SCN5A. When coupled with SkM1 expressing cells, cultured myocytes showed an increase in the dV/dtmax of the action potential. Expression of SCN5A had no such effect. In an in vitro cardiac syncytium, coculture of neonatal cardiac myocytes with SkM1 expressing but not SCN5A expressing cells significantly increased the conduction velocity under both normal and depolarized conditions. In an in vitro re-entry model induced by high frequency stimulation, expression of SkM1 also enhanced angular velocity of the induced re-entry. These results suggest that cells carrying a Na+ channel with a more depolarized inactivation curve can improve cardiac excitability and conduction in depolarized tissues. PMID:22526298
Social Exclusion and Modern Apprenticeships: A Comparison of Britain and the USA.
ERIC Educational Resources Information Center
Penn, Roger
1998-01-01
In the first wave of participation in Modern Apprenticeships in Britain, 89% were male, only 3% were ethnic minorities. Ethnic and gender exclusion has been central to apprenticeship structure in both Britain and the United States. However, the pattern in the United States has begun to change due to affirmative action. (SK)
1987-07-01
frozen rockfill dams on permafrost. In Proceedings of Conference on Buildings and Structures on Perma- frost, Noril’sk, Vol. III, p. 137-144. Sukhanov ...Razzorenov, F.F. (1968) Reed, R.E. (1966) Sleptsov, D.N. (1972) Stankevich, lu.N. (1964) Stavrovskll, A.P. (1977) Sukhanov , G.K. et al. (1978) *Thornton
Hernández-Bernal, Francisco; Castellanos-Sierra, Georgina; Valenzuela-Silva, Carmen M; Catasús-Álvarez, Karem M; Valle-Cabrera, Roselin; Aguilera-Barreto, Ana; López-Saura, Pedro A
2014-01-01
AIM: To compare the efficacy and safety of recombinant streptokinase (rSK) and phenylephrine-based suppositories in acute hemorrhoidal disease. METHODS: A multicenter (14 sites), randomized (1:1), open, parallel groups, active controlled trial was done. After inclusion, subjects with acute symptoms of hemorrhoids, who gave their written, informed consent to participate, were centrally randomized to receive, as outpatients, rSK (200000 IU) or 0.25% phenylephrine suppositories, which had different organoleptic characteristics. Treatment was administered by the rectal route, one unit every 6 h during 48 h for rSK, and up to a maximum of 5 d (20 suppositories) for phenylephrine. Evaluations were performed at 3, 5 and 10 d post-inclusion. The main end-point was the 5th-day complete clinical response (disappearance of pain and edema, and ≥ 70% reduction of the lesion size). Time to response and need for thrombectomy were secondary efficacy variables. Adverse events were evaluated too. RESULTS: 5th day complete response rates were 83/110 (75.5%) and 36/110 (32.7%) with rSK and phenylephrine suppositories, respectively. This 42.7% difference (95%CI: 30.5-54.2) was highly significant (P < 0.001). The advantage was detected since the early 3rd day evaluation (37.3% vs 6.4% for the rSK and active control groups, respectively; P < 0.001) and was kept even at the late 10th day assessment (83.6% vs 58.2% for rSK and phenylephrine, respectively; P < 0.001). Time for complete response was significantly shorter (P = 0.031; log-rank test) in the rSK group (median: 4.9 d; 95%CI: 4.8-5.0) with respect to the active control (median: 9.8 d; 95%CI: 9.8-10.0). Thrombectomy was necessary in 1/59 and 8/57 patients with baseline thrombosis in the rSK and phenylephrine groups, respectively (P = 0.016). There were no adverse events attributable to the experimental treatment. CONCLUSION: rSK suppositories showed a significant advantage over a widely used over-the-counter phenylephrine preparation for the treatment of acute hemorrhoidal illness, with an adequate safety profile. PMID:24587636
[Serum potassium levels and long-term mortality in the elderly with hypertension].
Heras Benito, M; Fernández-Reyes, M J; Guerrero Díaz, M T; Muñoz Pascual, A
There is increasing evidence that small variations within the normal range (3.5-5mEq/L) of potassium are associated with mortality. To determine whether there is an association between serum potassium level (sK) and mortality in a cohort of elderly hypertensive patients. A retrospective, observational study was conducted on patients who had sK levels available in a period of clinical stability during their recruitment between January and April 2006 and followed-up for 10 years. The study obtained a total of 62 stable patients, with a mean age of 82.19±6 years (range 69-97), with 74.2% women, 33.9% diabetics, 20.3% with a history of heart failure, Ischaemic heart disease was observed in 19.4% and 44.3% received Angiotensin Converting Enzyme (ACE) inhibitors. An analysis was performed on the mortality rate during the 10 year period. The statistics were performed using the SPSS15.0 package. There were 49 deaths. The sK had a normal distribution. Baseline mean sK levels and median were 4.45±0.5mEq/L (range 3.1-5.5 mEq/L). Baseline sK levels were significantly higher in diabetic patients and patients on ACE inhibitors. The patients that died had higher sK levels (4.53±0.49mEq/L versus 4.14±0.40mEq/L, P=.011). Survival estimated using Kaplan Meier showed that patients with sK levels higher than the median and P75 had higher mortality. In our study, sK levels greater than 4.45mEq/L were associated with mortality. When selecting antihypertensive treatment in hypertensive elderly patients,, the use of ACE inhibitors should be assessed individually, with close monitoring at sK levels and try to keep them in the lower limit of the normal range (<4.45 mEq/L). Copyright © 2017 SEH-LELHA. Publicado por Elsevier España, S.L.U. All rights reserved.
Zhao, Gang; Mi, Jingyi; Rui, Yongjun; Pan, Xiaoyun; Yao, Qun; Qiu, Yang
2017-01-01
Abstract Cold intolerance is a common complication of digital replantation. The exact etiology is unclear, but it is considered to be multifactorial, including nonsurgical characteristics, vascular, and neurologic conditions. Blood flow may play a significant role in cold intolerance. This study was designed to evaluate the correlation of digital blood flow, including volumetric flow rate (VFR) and skin blood flow (SkBF), with cold intolerance in replanted fingers. A retrospective study was conducted among patients who underwent digital replantation between 2010 and 2013. Patients were selected into study cohort based on the inclusion criteria. Surgical data was collected on each patient, including age, sex, injury mechanism, amputation level, ischemia time, number of arteries repaired, and whether or not vascular crisis occurred. Patients were included as study cohort with both nerves repaired and without chronic disease. Cold intolerance was defined as a Cold Intolerance Symptom Severity (CISS) score over 30. The arterial flow velocity and caliber were measured by Color Doppler Ultrasound and the digital VFR was calculated. The SkBF was measured by Laser Speckle Imager. Both VFR and SkBF were calculated as a percentage of the contralateral fingers. Comparative study of surgical data and blood flow was performed between the patient with and without cold intolerance. Correlation between VFR and SkBF was also analyzed. A total of 93 patients met inclusion criteria for the study. Approximately, 42 patients were identified as having cold intolerance. Fingers that survived vascular crisis had a higher incidence of cold intolerance with a lower VFR and SkBF. The VFR was higher in 2-artery replantation, but the SkBF and incidence of cold intolerance did not differ significantly. No differences were found in age, sex, injury mechanism, amputation level, or ischemia time. Furthermore, no correlation was found between VFR and SkBF. Cold intolerance of digital replantation is associated with decreased SkBF and VFR in the replanted fingers, which survived vascular crisis. Further work will be focused on how vascular crisis cause the decreasing of SkBF and VFR and the increasing chance of cold intolerance. PMID:29390590
Nitric oxide donors reduce the invasion ability of ovarian cancer cells in vitro.
Kielbik, Michal; Szulc, Izabela; Brzezinska, Marta; Bednarska, Katarzyna; Przygodzka, Patrycja; Sulowska, Zofia; Nowak, Marek; Klink, Magdalena
2014-11-01
The most important factors involved in tumor metastasis and angiogenesis are metalloproteinases (MMPs), vascular endothelial growth factor, and multifunctional transforming growth factor β1. These factors are responsible for extracellular matrix degradation, induction of vascular permeability, and enhancement of tumor cells' invasion and metastasis. Elevated expression and secretion of the above-mentioned factors are correlated with the higher aggressiveness of tumors and low patient survival for example, patients with ovarian cancer. Therefore, regulation of the expression, secretion, and activity of these factors is still considered a potent target for therapeutic intervention in cancer patients. Nitric oxide (NO) donors belong to the class of agents with multivalent targeted activities in cancer cells and are considered potential anticancer therapeutics. Our studies have shown that NO donors such as spermine/NO and diethylenetriamine/NO decrease the secretion of vascular endothelial growth factor-A from the OVCAR-3 ovarian cancer cell line, but not from the SK-OV-3 ovarian cancer cell line. The release of MMP-2 from both cell lines was reduced in a soluble guanylate cyclase-dependent manner by spermine/NO and diethylenetriamine/NO. Nevertheless, MMP-2 activity was only affected in SK-OV-3 cells. Both NO donors reduced the transmigration of the ovarian cancer cell lines. We did not observe any significant effect of spermine/NO and diethylenetriamine/NO on mRNA expression of the tested aggressiveness factors. In conclusion, our data indicated that NO donors reduced the metastatic potential of ovarian cancer cells, but its impact is rather low and requires high concentrations of donors. Moreover, both the tested cell lines differed in the susceptibility to NO donors.
Use of artificial neural networks to identify the origin of green macroalgae
NASA Astrophysics Data System (ADS)
Żbikowski, Radosław
2011-08-01
This study demonstrates application of artificial neural networks (ANNs) for identifying the origin of green macroalgae ( Enteromorpha sp. and Cladophora sp.) according to their concentrations of Cd, Cu, Ni, Zn, Mn, Pb, Na, Ca, K and Mg. Earlier studies confirmed that algae can be used for biomonitoring surveys of metal contaminants in coastal areas of the Southern Baltic. The same data sets were classified with the use of different structures of radial basis function (RBF) and multilayer perceptron (MLP) networks. The selected networks were able to classify the samples according to their geographical origin, i.e. Southern Baltic, Gulf of Gdańsk and Vistula Lagoon. Additionally in the case of macroalgae from the Gulf of Gdańsk, the networks enabled the discrimination of samples according to areas of contrasting levels of pollution. Hence this study shows that artificial neural networks can be a valuable tool in biomonitoring studies.
Xia, Guoping; Li, Jia; Li, Hanxiang; Long, Yuhua; Lin, Shao’e; Lu, Yongjun; He, Lei; Lin, Yongcheng; Liu, Lan; She, Zhigang
2014-01-01
A new alterporriol-type anthranoid dimer, alterporriol S (1), along with seven known anthraquinone derivatives, (+)-aS-alterporriol C (2), hydroxybostrycin (3), halorosellinia A (4), tetrahydrobostrycin (5), 9α-hydroxydihydrodesoxybostrycin (6), austrocortinin (7) and 6-methylquinizarin (8), were isolated from the culture broth of the mangrove fungus, Alternaria sp. (SK11), from the South China Sea. Their structures and the relative configurations were elucidated using comprehensive spectroscopic methods, including 1D and 2D NMR spectra. The absolute configurations of 1 and the axial configuration of 2 were defined by experimental and theoretical ECD spectroscopy. 1 was identified as the first member of alterporriols consisting of a unique C-10−C-2′ linkage. Atropisomer 2 exhibited strong inhibitory activity against Mycobacterium tuberculosis protein tyrosine phosphatase B (MptpB) with an IC50 value 8.70 μM. PMID:24840716
Stably Fluorescent Cell Line of Human Ovarian Epithelial Cancer Cells SK-OV-3ip-red.
Konovalova, E V; Shulga, A A; Chumakov, S P; Khodarovich, Yu M; Woo, Eui-Jeon; Deev, S M
2017-11-01
Stable red fluorescing line of human ovarian epithelial cancer cells SK-OV-3ip-red was generated expressing gene coding for protein TurboFP635 (Katushka) fluorescing in the far-red spectrum region with excitation and emission peaks at 588 and 635 nm, respectively. Fluorescence of SK-OV-3ip-red line remained high during long-term cell culturing and after cryogenic freezing. The obtained cell line SK-OV-3ip-red can serve a basis for a model of a scattered tumor with numerous/extended metastases and used both for testing anticancer drugs inhibiting metastasis growth and for non-invasive monitoring of the growth dynamics with high precision.
Observations of Sk-69 deg 203 and the interstellar extinction towards SN 1987A
NASA Technical Reports Server (NTRS)
Fitzpatrick, Edward L.; Walborn, Nolan R.
1990-01-01
Optical and UV spectroscopic observations of the Large Magellanic Cloud (LMC) star Sk-69 deg 203 are discussed. The optical data reveal Sk-69 deg 203 to be a BO.7 Ia supergiant with a moderate nitrogen enhancement, and its UV spectrum is consistent with this classification. UV interstellar extinction curves were constructed for the star using, as flux standards, two lightly reddened LMS supergiants, which bracket Sk-69 deg 203's spectral type. The resultant extinction curves are consistent with the extinction law derived previously for the 30 Doradus region, and the results for Sk-69 deg 203 suggest that the general 30 Doradus extinction law is appropriate for dereddening the observed fluxes of SN 1987A. Published H I 21 observations place SN 1987A in a region with a strong E-W gradient in the total hydrogen content. Comparison with the H I column density implied by the reddening indicates that the supernova is imbedded approximately in the middle of the main H I complex.
Solution properties of the capsular polysaccharide produced by Klebsiella pneumoniae SK1.
Cescutti, P; Paoletti, S; Navarini, L; Flaibani, A
1993-08-01
The solution properties of the capsular polysaccharide produced by Klebsiella pneumoniae SK1, SK1-CPS, were investigated by various methods. The SK1-CPS repeating unit is a branched pentasaccharide containing one glucuronic acid as single unit side chain; acetyl groups are present as non-carbohydrate substituents on the uronic acid residue in non-stoichiometric amounts. Chiro-optical, potentiometric, viscometric and rheological measurements have been performed in order to characterize the conformational behaviour of the polymer in water and in aqueous salt solutions. Under the investigated experimental conditions, changes of temperature, ionic strength and pH were shown not to induce any cooperative conformational transition. All the results obtained suggest that the solution conformation of SK1-CPS is a random coil with a certain degree of chain flexibility. The removal of the acetyl substituents apparently does not modify the overall conclusions drawn for the native polymer, except for an incipient tendency to aggregation revealed for high salt conditions.
2008-05-01
a Titanium and Gamma-TiAl Alloy, JOM, September 2005, 50-54 4 Chapter 1 [ref3] Caton, M.J., Jha, S.K., Larsen, J.M., Rosenberger, A.H., TMS...Figure 5: Notch 3 strain distribution at 900MPa 25 Chapter 3 Figure 6 : Notch 3 inverse pole figure of local microstructure. Figure 7: Notch 4 ...showing the local grain structure Figure 6 : Local strain distribution at 986MPa calculated from 36 Chapter 4 Figure 7: Secondary electron
Multi-stack InAs/InGaAs Sub-monolayer Quantum Dots Infrared Photodetectors
2013-01-01
013110 (2013) Demonstration of high performance bias-selectable dual- band short-/mid-wavelength infrared photodetectors based on type-II InAs/ GaSb ...been used for the growth of QD structures . These include the formation of self-assembled QD, for example, Stranski-Krastanov (SK) growth mode,8,9 atomic...confinement in SML-QD and the reduction in the amount of InAs used per layer of QD can help stack more layers in a 3-dimensional QD structure . Several
Novel Growth Technologies for In Situ Formation of Semiconductor Quantum Wire Structures
1994-01-01
as the alternative source for phosphine for the first time. We have developed the Stranski-Krastanow (SK) growth mode for the in-situ formation of InP...tertiarybutylphosphine (TBP) as the alternative source 3 for phosphine for the first time. At growth temperatures of 600oC specular surface morphology and mobilities...semi-insulating hnP buffer layer using ferrocene as the Fe-dopant. For the n-channel in our JFET structure disilane is used to obtain carrier
Changes in nutritional status among displaced North Korean children living in South Korea.
Lee, Soo-Kyung; Nam, So-Young; Hoffman, Daniel
2015-01-01
As many nations experience the nutrition transition, changes in the nutritional status of children moving from food insecure to food affluent societies has become an important, but infrequently studied, public health issue. To determine changes in the nutritional status of North Korean children after relocating to food-affluent South Korea (SK) from food-deficient North Korea (NK) and relationships of current nutritional status with food environment at birth and exposure to food affluent environments. Socioeconomic status, relocation history and anthropometric information were obtained from 70 NK children (6-15 years) living in SK, through questionnaires, interviews and direct measurements. Following the first 2 years in SK, the height and weight of NK children significantly (p = 0.000) improved, yet they were still shorter (p = 0.000) than SK peers, while the prevalence of obesity was similar to those of SK children. The likelihood of remaining stunted was significantly associated with older age and shorter residency in SK (p < 0.05), but there was no significant association with food security situation at birth. Even a short exposure to food affluent environments improved the nutritional status among children, but linear growth deficits are slow to recover as overall nutritional status remains poor compared to peers without exposures to food insecurity.
Virological and pathological characterization of an avian H1N1 influenza A virus.
Koo, Bon-Sang; Kim, Hye Kwon; Song, Daesub; Na, Woonsung; Song, Min-Suk; Kwon, Jin Jung; Wong, Sook-San; Noh, Ji Yeong; Ahn, Min-Ju; Kim, Doo-Jin; Webby, Richard J; Yoon, Sun-Woo; Jeong, Dae Gwin
2018-05-01
Gene segments from avian H1N1 influenza A viruses have reassorted with other influenza viruses to generate pandemic strains over the past century. Nevertheless, little effort has been invested in understanding the characteristics of avian H1N1 influenza viruses. Here, we present the genome sequence and a molecular and virological characterization of an avian influenza A virus, A/wild bird/Korea/SK14/2014 (A/SK14, H1N1), isolated from migratory birds in South Korea during the winter season of 2014-2015. Full-genome sequencing and phylogenetic analysis revealed that the virus belongs to the Eurasian avian lineage. Although it retained avian-receptor binding preference, A/SK14 virus also exhibited detectable human-like receptor binding and was able to replicate in differentiated primary normal human bronchial epithelial cells. In animal models, A/SK14 virus was moderately pathogenic in mice, and virus was detected in nasal washes from inoculated guinea pigs, but not in direct-contact guinea pigs. Although A/SK14 showed moderate pathogenicity and no evidence of transmission in a mammalian model, our results suggest that the dual receptor specificity of A/SK14-like virus might allow for a more rapid adaptation to mammals, emphasizing the importance of further continuous surveillance and risk-assessment activities.
Zhang, Yuanyuan; Liu, Zhe; Zhang, Qianwen; Chao, Zhenhua; Zhang, Pei; Xia, Fei; Jiang, Chenchen; Liu, Hao; Jiang, Zhiwen
2013-09-01
To study the effect of glycolysis inhibitor 3-bromopyruvate (3-BrPA) in inducing apoptosis of human breast carcinoma cells SK-BR-3 and the possible mechanism. MTT assay was used to detect the growth inhibition induced by 3-BrPA in breast cancer cells SK-BR-3. The apoptotic cells were detected by flow cytometry with propidium iodide (PI). ATP levels in the cells were detected by ATP assay kit, and DHE fluorescent probe technique was used to determine superoxide anion levels; the mitochondrial membrane potential was assessed using JC-1 staining assay. MTT assay showed that the proliferation of SK-BR-3 cells was inhibited by 3-BrPA in a time- and concentration-dependent manner. Exposure to 80, 160, and 320 µmol·L(-1) 3-BrPA for 24 h resulted in cell apoptosis rates of 6.7%, 22.3%, and 79.6%, respectively, and the intracellular ATP levels of SK-BR-3 cells treated with 80, 160, 320 µmol·L(-1) 3-BrPA for 5 h were 87.7%, 60.6%, and 23.7% of the control levels. 3-BrPA at 160 µmol·L(-1) increased reactive oxygen levels and lowered mitochondrial membrane potential of SK-BR-3 cells. 3-BrPA can inhibit cell proliferation, reduce the mitochondrial membrane potential and induce apoptosis in SK-BR-3 cells, the mechanism of which may involve a reduced ATP level by inhibiting glycolysis and increasing the reactive oxygen level in the cells.
Taheri, Leila; Boroujeni, Ali Zargham; Kargar Jahromi, Marzieh; Charkhandaz, Maryam; Hojat, Mohsen
2015-01-01
Emergency treatment of patients with acute myocardial infarction is very important. Streptokinase in Iran is often as the only clot-busting medication is used. The purpose of using streptokinase medication is to revive the ischemic heart tissue, although has dangerous complications too. Therefore, the present study aimed to determine the effect of streptokinase on reperfusion after acute myocardial infarction and its complications, has been designed and conducted. This is an Ex-post facto study. The study population included patients who suffer from acute myocardial infarction. The sample size was 300 patients, and 2 groups were matched, in variables of age, sex, underlying disease, frequencies and area of MI. Data collection did by researcher making questionnaire, that accept face and content validity by 10 expert researcher, the reliability was conducted with Spearman's test (r=0.85) by Test-retest method. Data analysis did by SPSS software: V 12. Mean of EF in SK group was (46.15±8.11) and in control group was (43.11±12.57). Significant relationship was seen between SK, arrhythmia occurring and improve EF reperfusion by chi-square test (p=0.028), (p=0.020).The most arrhythmia in SK group was Ventricular Tachycardia (20.7%). Significant statistical relation between SK and mortality were found by Chi-square test (p=0.001). But a meaningful statistical relation was not found between SK and pulmonary edema incidence (p=0.071). Nurses of CCU should be aware about SK complications such as hypotension, bleeding and arrhythmias. Proposed compare SK and tissue plasminogen drug in reperfusion and complications effect.
Hannah, Rachael M; Dunn, Kathryn M; Bonev, Adrian D; Nelson, Mark T
2011-05-01
Calcium-sensitive potassium (K(Ca)) channels have been shown to modulate the diameter of cerebral pial arteries; however, little is known regarding their roles in controlling cerebral parenchymal arterioles (PAs). We explored the function and cellular distribution of small-conductance (SK(Ca)) and intermediate-conductance (IK(Ca)) K(Ca) channels and large-conductance K(Ca) (BK(Ca)) channels in endothelial cells (ECs) and smooth muscle cells (SMCs) of PAs. Both SK(Ca) and IK(Ca) channels conducted the outward current in isolated PA ECs (current densities, ~20 pA/pF and ~28 pA/pF at +40 mV, respectively), but these currents were not detected in PA SMCs. In contrast, BK(Ca) currents were prominent in PA SMCs (~154 pA/pF), but were undetectable in PA ECs. Pressurized PAs constricted to inhibition of SK(Ca) (~16%) and IK(Ca) (~16%) channels, but were only modestly affected by inhibition of BK(Ca) channels (~5%). Blockade of SK(Ca) and IK(Ca) channels decreased resting cortical cerebral blood flow (CBF) by ~15%. NS309 (6,7-dichloro-1H-indole-2,3-dione3-oxime), a SK(Ca)/IK(Ca) channel opener, hyperpolarized PA SMCs by ~27 mV, maximally dilated pressurized PAs, and increased CBF by ~40%. In conclusion, these data show that SK(Ca) and IK(Ca) channels in ECs profoundly modulate PA tone and CBF, whereas BK(Ca) channels in SMCs only modestly influence PA diameter.
Evaluation of ultrasound in assessing body composition of high school wrestlers.
Utter, Alan C; Hager, Marion E
2008-05-01
To evaluate the accuracy of ultrasound (ULTRA) in assessing fat-free mass (FFM) in comparison with hydrostatic weighing (HW) and skinfolds (SK) in high school wrestlers in a hydrated state. Body composition was determined by ULTRA, HW, and three-site SK in 70 high school wrestlers (mean +/- SD: age, 15.5 +/- 1.5; height, 1.60 +/- 0.08 m; body mass, 65.8 +/- 12.7 kg). For all methods, body density (Db) was converted to percent body fat (%BF) using the Brozek equation. Hydration state was quantified by evaluating urine specific gravity. There were no significant differences for estimated FFM between ULTRA (57.2 +/- 9.7 kg) and HW (57.0 +/- 9.9 kg); however, SK (54.9 +/- 8.8 kg) were significantly different from HW. The standard errors of estimate for FFM with HW as the reference method were 2.40 kg for ULTRA and 2.74 kg for SK. Significant correlations were found for FFM between HW and ULTRA (r = 0.97, P < 0.001) and between HW and SK (r = 0.96, P < 0.001). A systematic bias was found for SK, as the difference between SK and HW significantly correlated with the FFM average of the two methods (r = -0.38, P < 0.001). This systematic bias was not found for ULTRA (r = - 0.07). This study demonstrates that ULTRA provides similar estimates of FFM when compared with HW in a heterogeneous high school wrestling population during a hydrated state. ULTRA should be considered as an alternative field-based method of estimating the FFM of high school wrestlers.
On the star partition dimension of comb product of cycle and path
NASA Astrophysics Data System (ADS)
Alfarisi, Ridho; Darmaji
2017-08-01
Let G = (V, E) be a connected graphs with vertex set V(G), edge set E(G) and S ⊆ V(G). Given an ordered partition Π = {S1, S2, S3, …, Sk} of the vertex set V of G, the representation of a vertex v ∈ V with respect to Π is the vector r(v|Π) = (d(v, S1), d(v, S2), …, d(v, Sk)), where d(v, Sk) represents the distance between the vertex v and the set Sk and d(v, Sk) = min{d(v, x)|x ∈ Sk }. A partition Π of V(G) is a resolving partition if different vertices of G have distinct representations, i.e., for every pair of vertices u, v ∈ V(G), r(u|Π) ≠ r(v|Π). The minimum k of Π resolving partition is a partition dimension of G, denoted by pd(G). The resolving partition Π = {S1, S2, S3, …, Sk } is called a star resolving partition for G if it is a resolving partition and each subgraph induced by Si, 1 ≤ i ≤ k, is a star. The minimum k for which there exists a star resolving partition of V(G) is the star partition dimension of G, denoted by spd(G). Finding the star partition dimension of G is classified to be a NP-Hard problem. In this paper, we will show that the partition dimension of comb product of cycle and path namely Cm⊳Pn and Pn⊳Cm for n ≥ 2 and m ≥ 3.
NASA Astrophysics Data System (ADS)
Grzetic, Douglas J.; Delaney, Kris T.; Fredrickson, Glenn H.
2018-05-01
We derive the effective Flory-Huggins parameter in polarizable polymeric systems, within a recently introduced polarizable field theory framework. The incorporation of bead polarizabilities in the model self-consistently embeds dielectric response, as well as van der Waals interactions. The latter generate a χ parameter (denoted χ ˜ ) between any two species with polarizability contrast. Using one-loop perturbation theory, we compute corrections to the structure factor S (k ) and the dielectric function ɛ ^ (k ) for a polarizable binary homopolymer blend in the one-phase region of the phase diagram. The electrostatic corrections to S(k) can be entirely accounted for by a renormalization of the excluded volume parameter B into three van der Waals-corrected parameters BAA, BAB, and BBB, which then determine χ ˜ . The one-loop theory not only enables the quantitative prediction of χ ˜ but also provides useful insight into the dependence of χ ˜ on the electrostatic environment (for example, its sensitivity to electrostatic screening). The unapproximated polarizable field theory is amenable to direct simulation via complex Langevin sampling, which we employ here to test the validity of the one-loop results. From simulations of S(k) and ɛ ^ (k ) for a system of polarizable homopolymers, we find that the one-loop theory is best suited to high concentrations, where it performs very well. Finally, we measure χ ˜ N in simulations of a polarizable diblock copolymer melt and obtain excellent agreement with the one-loop theory. These constitute the first fully fluctuating simulations conducted within the polarizable field theory framework.
A New In Vitro Co-Culture Model Using Magnetic Force-Based Nanotechnology.
Takanari, Hiroki; Miwa, Keiko; Fu, XianMing; Nakai, Junichi; Ito, Akira; Ino, Kousuke; Honda, Hiroyuki; Tonomura, Wataru; Konishi, Satoshi; Opthof, Tobias; van der Heyden, Marcel Ag; Kodama, Itsuo; Lee, Jong-Kook
2016-10-01
Skeletal myoblast (SkMB) transplantation has been conducted as a therapeutic strategy for severe heart failure. However, arrhythmogenicity following transplantation remains unsolved. We developed an in vitro model of myoblast transplantation with "patterned" or "randomly-mixed" co-culture of SkMBs and cardiomyocytes enabling subsequent electrophysiological, and arrhythmogenic evaluation. SkMBs were magnetically labeled with magnetite nanoparticles and co-cultured with neonatal rat ventricular myocytes (NRVMs) on multi-electrode arrays. SkMBs were patterned by a magnet beneath the arrays. Excitation synchronicity was evaluated by Ca(2+) imaging using a gene-encoded Ca(2+) indicator, G-CaMP2. In the monoculture of NRVMs (control), conduction was well-organized. In the randomly-mixed co-culture of NRVMs and SkMBs (random group), there was inhomogeneous conduction from multiple origins. In the "patterned" co-culture where an en bloc SKMB-layer was inserted into the NRVM-layer, excitation homogenously propagated although conduction was distorted by the SkMB-area. The 4-mm distance conduction time (CT) in the random group was significantly longer (197 ± 126 ms) than in control (17 ± 3 ms). In the patterned group, CT through NRVM-area did not change (25 ± 3 ms), although CT through the SkMB-area was significantly longer (132 ± 77 ms). The intervals between spontaneous excitation varied beat-to-beat in the random group, while regular beating was recorded in the control and patterned groups. Synchronized Ca(2+) transients of NRVMs were observed in the patterned group, whereas those in the random group were asynchronous. Patterned alignment of SkMBs is feasible with magnetic nanoparticles. Using the novel in vitro model mimicking cell transplantation, it may become possible to predict arrhythmogenicity due to heterogenous cell transplantation. J. Cell. Physiol. 231: 2249-2256, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Perez-Calatayud, Jose; Richart, Jose; Guirado, Damián; Pérez-García, Jordi; Rodríguez, Silvia; Santos, Manuel
2012-01-01
Purpose SeedSelectron® v1.26b (Nucletron BV, The Netherlands) is an afterloader system used in prostate interstitial permanent brachytherapy with I-125 selectSeed seeds. It contains a diode array to assay all implanted seeds. Only one or two seeds can be extracted during the surgical procedure and assayed using a well chamber to check the manufacturer air-kerma strength (SK) and to calibrate the diode array. Therefore, it is not feasible to assay 5–10% seeds as required by the AAPM-ESTRO. In this study, we present a practical solution of the SeedSelectron® users to fulfill the AAPM- ESTRO recommendations. Material and methods The method is based on: a) the SourceCheck® well ionization chamber (PTW, Germany) provided with a PTW insert; b) n = 10 selectSeed from the same batch and class as the seeds for the implant; c) the Nucletron insert to accommodate the n = 10 seeds on the SourceCheck® and to measure their averaged SK. Results for 56 implants have been studied comparing the SK value from the manufacturer with the one obtained with the n = 10 seeds using the Nucletron insert prior to the implant and with the SK of just one seed measured with the PTW insert during the implant. Results We are faced with SK deviation for individual seeds up to 7.8%. However, in the majority of cases SK is in agreement with the manufacturer value. With the method proposed using the Nucletron insert, the large deviations of SK are reduced and for 56 implants studied no deviation outside the range of the class were found. Conclusions The new Nucletron insert and the proposed procedure allow to evaluate the SK of the n = 10 seeds prior to the implant, fulfilling the AAPM-ESTRO recommendations. It has been adopted by Nucletron to be extended to seedSelectron® users under request. PMID:23346136
NASA Astrophysics Data System (ADS)
Khosravinia, H.
2015-11-01
An experiment was conducted to examine the effects on mortality, production performance, water intake (WI), and organ weight of Satureja khuzistanica essential oil (SkEO) using 720 1-day-old Arian broiler chicks in a 42-day trial. Experimental treatments were addition of 0 (control-), 200, 300, 400, and 500 mg/L SkEO or 500 mg/L polysorbate 80 (control+) into drinking water. The birds were kept under natural ambient temperatures 4 to 6 °C above standard recommendation from days 22 to 42 of age. Addition of SkEO into drinking water at 200 and 500 mg/L decreased weight gain ( P < 0.05) of the birds from days 29 to 35 of age with no differences in feed intake (FI) and feed conversion ratio (FCR) compared to control groups ( P > 0.05). Supplementation of drinking water with 200, 300, 400, and 500 mg/L SkEO resulted in a 0.47, 4.40, 8.60, and 12.93 % decrease in WI, respectively, from days 1 to 42 of age. The calculated European broiler index was greater for the birds received 400 mg/L of SkEO in their drinking water compared with that of the other birds ( P < 0.05). Pancreas percentage was increased for the birds received 200 to 500 mg/L SkEO at days 21 and 42 of age compared with that of the control- birds ( P < 0.05). The gall bladder weight was 17.56, 40.50, 12.16, and 38.73 % greater for the birds received 200, 300, 400, and 500 mg/L SkEO compared with that of the control- birds, respectively. The results showed that an addition of 400 mg/L SkEO into drinking water for heat-stressed broiler chickens improves economic efficiency possibly by promoting digestion process, creating miniscule improvement in FCR and lowered mortality rate.
Khosravinia, H
2015-11-01
An experiment was conducted to examine the effects on mortality, production performance, water intake (WI), and organ weight of Satureja khuzistanica essential oil (SkEO) using 720 1-day-old Arian broiler chicks in a 42-day trial. Experimental treatments were addition of 0 (control(-)), 200, 300, 400, and 500 mg/L SkEO or 500 mg/L polysorbate 80 (control(+)) into drinking water. The birds were kept under natural ambient temperatures 4 to 6 °C above standard recommendation from days 22 to 42 of age. Addition of SkEO into drinking water at 200 and 500 mg/L decreased weight gain (P < 0.05) of the birds from days 29 to 35 of age with no differences in feed intake (FI) and feed conversion ratio (FCR) compared to control groups (P > 0.05). Supplementation of drinking water with 200, 300, 400, and 500 mg/L SkEO resulted in a 0.47, 4.40, 8.60, and 12.93% decrease in WI, respectively, from days 1 to 42 of age. The calculated European broiler index was greater for the birds received 400 mg/L of SkEO in their drinking water compared with that of the other birds (P < 0.05). Pancreas percentage was increased for the birds received 200 to 500 mg/L SkEO at days 21 and 42 of age compared with that of the control(-) birds (P < 0.05). The gall bladder weight was 17.56, 40.50, 12.16, and 38.73% greater for the birds received 200, 300, 400, and 500 mg/L SkEO compared with that of the control(-) birds, respectively. The results showed that an addition of 400 mg/L SkEO into drinking water for heat-stressed broiler chickens improves economic efficiency possibly by promoting digestion process, creating miniscule improvement in FCR and lowered mortality rate.
Krishnamurthi, S; Bhattacharya, A; Mayilraj, S; Saha, P; Schumann, P; Chakrabarti, T
2009-06-01
In the course of a study of the prokaryotic diversity of a landfill site in Chandigarh, India, a strain designated SK 55(T) was isolated and characterized using a polyphasic approach. Its 16S rRNA gene sequence showed closest similarity (98.3 %) to that of Sporosarcina macmurdoensis CMS 21w(T). The sequence similarity to strains of other hitherto described species of Sporosarcina was less than 95.5 %. Strain SK 55(T) contains peptidoglycan of the A4alpha type (l-Lys-d-Asp), MK-8 and MK-7 as the major menaquinones and iso-C(15 : 0) as the major fatty acid. Strain SK 55(T), Sporosarcina macmurdoensis and Sporosarcina ureae, the type species of the genus, had some polar lipids in common (diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, a phospholipid and an unknown lipid). However, an aminolipid, an aminophospholipid and an unknown lipid found in the former two organisms are similar, though not identical, but quite different from the profile of S. ureae. The genomic DNA G+C contents of strain SK 55(T) (46.0 mol%) and S. macmurdoensis CMS 21w(T) (44.0 mol%) are higher than those reported for the majority of species of Sporosarcina (36-42 mol%). As revealed by 16S rRNA gene sequence analysis, strain SK 55(T) and S. macmurdoensis CMS 21w(T) form a clade which is distinct from the clade occupied by other species of Sporosarcina. On the basis of phenotypic characteristics including chemotaxonomic data and analysis of the 16S rRNA gene sequence, we conclude that strain SK 55(T) should be considered as a member of a novel genus and species, for which the name Paenisporosarcina quisquiliarum gen. nov., sp. nov. is proposed. The type strain of Paenisporosarcina quisquiliarum is SK 55(T) (=MTCC7604(T) =JCM 14041(T)). S. macmurdoensis CMS 21w(T) shows more similarity in its 16S rRNA gene sequence (98.3 %), DNA G+C content and polar lipid profile to strain SK 55(T) than to S. ureae DSM 2281(T). Phylogenetically, it forms a coherent cluster with strain SK 55(T) which is separate from the Sporosarcina cluster. Moreover, iso-C(15 : 0), anteiso-C(15 : 0) and C(16 : 1)omega7c alcohol are the three major fatty acids in both S. macmurdoensis CMS 21w(T) and SK 55(T). All these data suggest that S. macmurdoensis should be a member of the genus Paenisporosarcina. However, S. macmurdoensis can be differentiated from SK 55(T) in several physiological and biochemical characteristics, especially in the patterns of oxidation and acid production from carbohydrates. The genomic relatedness of S. macmurdoensis CMS 21w(T) and strain SK 55(T) was also very low (18.0 %). It is therefore logical to transfer Sporosarcina macmurdoensis to the newly created genus as Paenisporosarcina macmurdoensis comb. nov. The type strain is CMS 21w(T) (=MTCC4670(T) =DSM 15428(T)).
Particle clustering within a two-phase turbulent pipe jet
NASA Astrophysics Data System (ADS)
Lau, Timothy; Nathan, Graham
2016-11-01
A comprehensive study of the influence of Stokes number on the instantaneous distributions of particles within a well-characterised, two-phase, turbulent pipe jet in a weak co-flow was performed. The experiments utilised particles with a narrow size distribution, resulting in a truly mono-disperse particle-laden jet. The jet Reynolds number, based on the pipe diameter, was in the range 10000 <= ReD <= 40000 , while the exit Stokes number was in the range 0 . 3 <= SkD <= 22 . 4 . The particle mass loading was fixed at ϕ = 0 . 4 , resulting in a flow that was in the two-way coupling regime. Instantaneous particle distributions within a two-dimensional sheet was measured using planar nephelometry while particle clusters were identified and subsequently characterised using an in-house developed technique. The results show that particle clustering is significantly influenced by the exit Stokes number. Particle clustering was found to be significant for 0 . 3 <= SkD <= 5 . 6 , with the degree of clustering increasing as SkD is decreased. The clusters, which typically appeared as filament-like structures with high aspect ratio oriented at oblique angles to the flow, were measured right from the exit plane, suggesting that they were generated inside the pipe. The authors acknowledge the financial contributions by the Australian Research Council (Grant No. DP120102961) and the Australian Renewable Energy Agency (Grant No. USO034).
Pitaksakulrat, Opal; Webster, Bonnie L; Webster, Joanne P; Laha, Thewarach; Saijuntha, Weerachai; Lamberton, Poppy H L; Kiatsopit, Nadda; Andrews, Ross H; Petney, Trevor N; Sithithaworn, Paiboon
2018-04-19
The liver fluke Opisthorchis viverrini sensu lato causes serious public-health problems in Northeast Thailand and Southeast Asian countries. A hypothesis has been proposed that O. viverrini represents a species complex with varying levels of genetic differentiation in Thailand and Lao PDR. This study aimed to clarify whether O. viverrini populations can be genetically divided into separate taxa. We collected O. viverrini s.l. from eight different locations in Lao PDR and Thailand. The results of nad1, cox1, CF-int6, Pm-int9, ITS2 and 28S rDNA sequence analysis revealed that sub-structuring occurred between the eight populations. We found that O. viverrini s.l. from Sakon Nakhon (SK), Thailand, shows significant genetic differentiation (P < .05) from all other isolates from different localities in Thailand and Lao PDR. This was supported by haplotype and phylogenetic tree analyses in which the SK isolate was separated from all other isolates. This suggests that O. viverrini s.l. from SK is a cryptic species. The data, however, also confirm the association between genetic groups of O. viverrini s.l. and specific wetland systems, and raise important questions regarding the epidemiological significance of these genetic differences. Copyright © 2018 Elsevier B.V. All rights reserved.
Andrew J. Hansen; Linda Bowers Phillips; Curtis H. Flather; Jim Robinson-Cox
2011-01-01
We evaluated the leading hypotheses on biophysical factors affecting species richness for Breeding Bird Survey routes from areas with little influence of human activities.We then derived a best model based on information theory, and used this model to extrapolate SK across North America based on the biophysical predictor variables. The predictor variables included the...
Li, Hsin-Hua; Lu, Fung-Jou; Hung, Hui-Chih; Liu, Guang-Yaw; Lai, Te-Jen; Lin, Chih-Li
2015-01-01
Humic acid (HA) is a possible etiological factor associated with for several vascular diseases. It is known that vascular risk factors can directly increase the susceptibility to Alzheimer’s disease (AD), which is a neurodegenerative disorder due to accumulation of amyloid β (Aβ) peptide in the brain. However, the role that HA contributes to Aβ-induced cytotoxicity has not been demonstrated. In the present study, we demonstrate that HA exhibits a synergistic effect enhancing Aβ-induced cytotoxicity in cultured human SK-N-MC neuronal cells. Furthermore, this deterioration was mediated through the activation of endoplasmic reticulum (ER) stress by stimulating PERK and eIF2α phosphorylation. We also observed HA and Aβ-induced cytotoxicity is associated with mitochondrial dysfunction caused by down-regulation of the Sirt1/PGC1α pathway, while in contrast, treating the cells with the ER stress inhibitor Salubrinal, or over-expression of Sirt1 significantly reduced loss of cell viability by HA and Aβ. Our findings suggest a new mechanism by which HA can deteriorate Aβ-induced cytotoxicity through modulation of ER stress, which may provide significant insights into the pathogenesis of AD co-occurring with vascular injury. PMID:25961951
Ha, Jang-Ho; Kim, Ha-Neul; Moon, Ki-Beom; Jeon, Jae-Heung; Jung, Dai-Hyun; Kim, Su-Jung; Mason, Hugh S; Shin, Seo-Yeon; Kim, Hyun-Soon; Park, Kyung-Mok
2017-07-01
Responding to the need for recombinant acidic fibroblast growth factor in the pharmaceutical and cosmetic industries, we established a scalable expression system for recombinant human aFGF using transient and a DNA replicon vector expression in Nicotiana benthamiana . Recombinant human-acidic fibroblast growth factor was recovered following Agrobacterium infiltration of N. benthamiana . The optimal time point at which to harvest recombinant human acidic fibroblast growth factor expressing leaves was found to be 4 days post-infiltration, before necrosis was evident. Commassie-stained SDS-PAGE gels of His-tag column eluates, concentrated using a 10 000 molecular weight cut-off column, showed an intense band at the expected molecular weight for recombinant human acidic fibroblast growth factor. An immunoblot confirmed that this band was recombinant human acidic fibroblast growth factor. Up to 10 µg recombinant human-acidic fibroblast growth factor/g of fresh leaves were achieved by a simple affinity purification protocol using protein extract from the leaves of agroinfiltrated N. benthamiana . The purified recombinant human acidic fibroblast growth factor improved the survival rate of UVB-irradiated HaCaT and CCD-986sk cells approximately 89 and 81 %, respectively. N. benthamiana -derived recombinant human acidic fibroblast growth factor showed similar effects on skin cell proliferation and UVB protection compared to those of Escherichia coli -derived recombinant human acidic fibroblast growth factor. Additionally, N. benthamiana- derived recombinant human acidic fibroblast growth factor increased type 1 procollagen synthesis up to 30 % as well as reduced UVB-induced intracellular reactive oxygen species generation in fibroblast (CCD-986sk) cells.UVB is a well-known factor that causes various types of skin damage and premature aging. Therefore, the present study demonstrated that N. benthamiana -derived recombinant human acidic fibroblast growth factor effectively protects skin cell from UVB, suggesting its potential use as a cosmetic or therapeutic agent against skin photoaging. Georg Thieme Verlag KG Stuttgart · New York.
2015-01-24
Lilleodden, P. Anderson, J.T. Wyrobek, Acta Materialia 44 (1996) 3585-3598. [75] W.W. Gerberich, S. Venkataraman , J. Nelson, H. Huang, E. Lilleodden, W...629-644. [76] W.W. Gerberich, S.K. Venkataraman , H. Huang, S.E. Harvey, D.L. Kohlstedt, Acta Metallurgica et Materialia 43 (1995) 1569. [77] A.E
Tsuji, Masaharu; Kudoh, Sakae; Hoshino, Tamotsu
2015-01-22
Mrakia blollopis strain SK-4 was isolated from an algal mat of Naga-ike, a lake in Skarvsnes, East Antarctica. Here, we report the draft genome sequence of M. blollopis SK-4. This is the first report on the genome sequence of any cold-adapted fungal species. Copyright © 2015 Tsuji et al.
Role of critical fluctuations in the formation of a skyrmion lattice in MnSi
NASA Astrophysics Data System (ADS)
Chubova, N. M.; Moskvin, E. V.; Dyad'kin, V. A.; Dewhurst, Ch.; Maleev, S. V.; Grigor'ev, S. V.
2017-11-01
The region in the H- T phase diagram near the critical temperature ( T c ) of the cubic helicoidal MnSi magnet is comprehensively studied by small-angle neutron diffraction. Magnetic field H is applied along the [111] axis. The experimental geometry is chosen to simultaneously observe the following three different magnetic states of the system: (a) critical fluctuations of a spin spiral with randomly orientated wavevector k f , (b) conical structure with k c ǁ H, and (c) hexagonal skyrmion lattice with k sk ⊥ H. Both states (conical structure, and skyrmion lattice) are shown to exist above critical temperature T c = 29 K against the background of the critical fluctuations of a spin spiral. The conical lattice is present up to the temperatures where fluctuation correlation length ξ becomes comparable with pitch of spiral d s . The skyrmion lattice is localized near T c and is related to the fluctuations of a spiral with correlation length ξ ≈ 2 d s , and the propagation vector is normal to the field ( k sk ⊥ H). These spiral fluctuations are assumed to be the defects that stabilize the skyrmion lattice and promote its formation.
NASA Astrophysics Data System (ADS)
Archer, Andrew J.; Chacko, Blesson; Evans, Robert
2017-07-01
In classical density functional theory (DFT), the part of the Helmholtz free energy functional arising from attractive inter-particle interactions is often treated in a mean-field or van der Waals approximation. On the face of it, this is a somewhat crude treatment as the resulting functional generates the simple random phase approximation (RPA) for the bulk fluid pair direct correlation function. We explain why using standard mean-field DFT to describe inhomogeneous fluid structure and thermodynamics is more accurate than one might expect based on this observation. By considering the pair correlation function g(x) and structure factor S(k) of a one-dimensional model fluid, for which exact results are available, we show that the mean-field DFT, employed within the test-particle procedure, yields results much superior to those from the RPA closure of the bulk Ornstein-Zernike equation. We argue that one should not judge the quality of a DFT based solely on the approximation it generates for the bulk pair direct correlation function.
Taheri, Leila; Zargham-Boroujeni, Ali; Jahromi, Marzieh Kargar; Charkhandaz, Maryam; Hojat, Mohsen
2015-01-01
Introduction: Emergency treatment of patients with acute myocardial infarction is very important. Streptokinase in Iran is often as the only clot-busting medication is used. The purpose of using streptokinase medication is to revive the ischemic heart tissue, although has dangerous complications too. Therefore, the present study aimed to determine the effect of streptokinase on reperfusion after acute myocardial infarction and its complications, has been designed and conducted. Materials and Methods: This is an Ex-post facto study. The study population included patients who suffer from acute myocardial infarction. The sample size was 300 patients, and 2 groups were matched, in variables of age, sex, underlying disease, frequencies and area of MI. Data collection did by researcher making questionnaire, that accept face and content validity by 10 expert researcher, the reliability was conducted with Spearman’s test (r=0.85) by Test-retest method. Data analysis did by SPSS software: V 12. Findings: Mean of EF in SK group was (46.15±8.11) and in control group was (43.11±12.57). Significant relationship was seen between SK, arrhythmia occurring and improve EF reperfusion by chi-square test (p=0.028), (p=0.020). The most arrhythmia in SK group was Ventricular Tachycardia (20.7%). Significant statistical relation between SK and mortality were found by Chi-square test (p=0.001). But a meaningful statistical relation was not found between SK and pulmonary edema incidence (p=0.071). Conclusions: Nurses of CCU should be aware about SK complications such as hypotension, bleeding and arrhythmias. Proposed compare SK and tissue plasminogen drug in reperfusion and complications effect. PMID:25946921
Zhan, Qinglei; Tsai, Sauna; Lu, Yonghai; Wang, Chunmei; Kwan, Yiuwa; Ngai, Saiming
2013-01-01
Neuroblastoma is the second most common solid tumor diagnosed during infancy. The survival rate among children with high-risk neuroblastoma is less than 40%, highlighting the urgent needs for new treatment strategies. PCI-24781 is a novel hydroxamic acid-based histone deacetylase (HDAC) inhibitor that has high efficacy and safety for cancer treatment. However, the underlying mechanisms of PCI-24781 are not clearly elucidated in neuroblastoma cells. In the present study, we demonstrated that PCI-24781 treatment significantly inhibited tumor growth at very low doses in neuroblastoma cells SK-N-DZ, not in normal cell line HS-68. However, PCI-24781 caused the accumulation of acetylated histone H3 both in SK-N-DZ and HS-68 cell line. Treatment of SK-N-DZ with PCI-24781 also induced cell cycle arrest in G2/M phase and activated apoptosis signaling pathways via the up-regulation of DR4, p21, p53 and caspase 3. Further proteomic analysis revealed differential protein expression profiles between non-treated and PCI-24781 treated SK-N-DZ cells. Totally 42 differentially expressed proteins were identified by MALDI-TOF MS system. Western blotting confirmed the expression level of five candidate proteins including prohibitin, hHR23a, RuvBL2, TRAP1 and PDCD6IP. Selective knockdown of RuvBL2 rescued cells from PCI-24781-induced cell death, implying that RuvBL2 might play an important role in anti-tumor activity of PCI-24781 in SK-N-DZ cells. The present results provide a new insight into the potential mechanism of PCI-24781 in SK-N-DZ cell line. PMID:23977108
Rivas, Eric; McEntire, Serina J.; Herndon, David N.; Mlcak, Ronald P.; Suman, Oscar E.
2017-01-01
Objective Tested the hypothesis that propranolol, a drug given to burn patients to reduce hypermetabolism/cardiac stress, may inhibit heat dissipation by changing the sensitivity of skin blood flow (SkBF) to local heating under neutral and hot conditions. Methods In a randomized double-blind study, a placebo was given to 8 burned children while propranolol was given to 13 burned children with similar characteristics (mean ± SD: 11.9±3y, 147±20cm, 45±23kg, 56±12% TBSA). Non-burned children (n=13, 11.4±3y, 152±15cm, 52±13kg) served as healthy controls. A progressive local heating protocol characterized SkBF responses in burned and unburned skin and non-burned control skin under the two environmental conditions (23°C and 34°C) via laser-Doppler flowmetry. Results Resting SkBF was greater in burned and unburned skin compared to the non-burned control (main effect: skin, P<0.0001; 57±32 burned; 38±36 unburned vs 9±8 control %SkBFmax). No difference was found for maximal SkBF capacity to local heating between groups. Additionally, dose response curves for the sensitivity of SkBF to local heating were not different among burned or unburned skin, and non-burned control skin (EC50, P>0.05) under either condition. Conclusion Therapeutic propranolol does not negatively affect SkBF under neutral or hot environmental conditions and further compromise temperature regulation in burned children. PMID:28071840
HSP-70 mitigates LPS/SKI-induced cell damage by increasing sphingosine kinase 1 (SK1).
Ding, Xuan Z; Feng, Xiao R; Borschel, Richard H; Nikolich, Mikeljon P; Feng, Jie; Li, Yan S; Hoover, David L
2010-06-01
Heat shock proteins (HSPs) are potent protectors of cellular integrity against environmental stresses, including toxic microbial products. To investigate the mechanism of HSP-70 cell protection against bacterial lipopolysaccharide (LPS), we established a stable HSP-70 gene-transfected RAW 264.7 murine macrophage model of LPS-induced cell death. Bacterial LPS increases the activity of sphingosine kinase 1 (SK1), which catalyzes formation of sphingosine-1-phosphate (S1P). S1P functions as a critical signal for initiation and maintenance of diverse aspects of immune cell activation and function. When mouse macrophages were incubated with Escherichia coli LPS (1 microg/ml) and sphingosine kinase inhibitor (SKI, 5 microM), 90% of cells died. Neither LPS nor SKI alone at these doses damaged the cells. The LPS/SKI-induced cell death was partially reversed by overexpression of HSP-70 in gene-transfected macrophages. The specificity of HSP-70 in this reversal was demonstrated by transfection of HSP-70-specific siRNA. Down-regulation of HSP-70 expression after transfection of siRNA specific for HSP-70 was associated with increased LPS/SKI-induced cell damage. Overexpression of human or murine HSP-70 (HSPA1A and Hspa1a, respectively) increased both cellular SK1 mRNA and protein levels. Cellular heat shock also increased SK1 protein. These studies confirm the importance of SK1 as a protective moiety in LPS-induced cell injury and demonstrate that HSP-70-mediated protection from cells treated with LPS/SKI is accompanied by upregulating expression of SK1. HSP-70-mediated increases in SK1 and consequent increased levels of S1P may also play a role in protection of cells from other processes that lead to programmed cell death. Published by Elsevier Inc.
Rivas, Eric; McEntire, Serina J; Herndon, David N; Mlcak, Ronald P; Suman, Oscar E
2017-05-01
We tested the hypothesis that propranolol, a drug given to burn patients to reduce hypermetabolism/cardiac stress, may inhibit heat dissipation by changing the sensitivity of skin blood flow (SkBF) to local heating under neutral and hot conditions. In a randomized double-blind study, a placebo was given to eight burned children, while propranolol was given to 13 burned children with similar characteristics (mean±SD: 11.9±3 years, 147±20 cm, 45±23 kg, 56±12% Total body surface area burned). Nonburned children (n=13, 11.4±3 years, 152±15 cm, 52±13 kg) served as healthy controls. A progressive local heating protocol characterized SkBF responses in burned and unburned skin and nonburned control skin under the two environmental conditions (23 and 34°C) via laser Doppler flowmetry. Resting SkBF was greater in burned and unburned skin compared to the nonburned control (main effect: skin, P<.0001; 57±32 burned; 38±36 unburned vs 9±8 control %SkBF max ). No difference was found for maximal SkBF capacity to local heating between groups. Additionally, dose-response curves for the sensitivity of SkBF to local heating were not different among burned or unburned skin, and nonburned control skin (EC 50 , P>.05) under either condition. Therapeutic propranolol does not negatively affect SkBF under neutral or hot environmental conditions and further compromise temperature regulation in burned children. © 2017 John Wiley & Sons Ltd.
Hua, X; Lundberg, J M; Theodorsson-Norheim, E; Brodin, E
1984-12-01
The effects of substance P (SP), substance K (SK), physalaemin, eledoisin, kassinin, neuromedin K and bombesin on blood pressure, heart rate, respiratory insufflation pressure and plasma extravasation were studied in the guinea-pig. All tachykinins except neuromedin K caused a fall in blood pressure with rather similar potency. The hypotensive response after physalaemin was comparatively more long-lasting. SK and eledoisin (2.5 nmol X kg-1 i.v.) caused an initial bradycardia which then changed into tachycardia. The other tachykinins induced a slowly developing tachycardia. Neuromedin K (up to 40 nmol X kg-1) did not influence heart rate. SK, kassinin and eledoisin were more potent than SP and physalaemin in increasing respiratory insufflation pressure. The effect of SK had a particularly long duration. Neuromedin K only induced a weak increase in insufflation pressure at a very high dose. All tachykinins except neuromedin K induced an increase in vascular permeability to plasma proteins in many visceral organs, as indicated by Evans blue extravasation. The trachea and ureter were the most sensitive organs with regard to this effect. Physalaemin and eledoisin were generally more potent in increasing vascular permeability in various organs than SP and SK. The maximal permeability-increasing effect of SK was smaller than that of SP, although the potency was similar. Bombesin increased insufflation pressure with no clearcut effects on vascular permeability. It is concluded that in the same species, i.e. guinea-pig, several tachykinins have rather similar hypotensive action, while the vascular permeability increase to plasma proteins is especially pronounced after physalaemin and eledoisin. SK, kassinin and eledoisin have prominent bronchoconstrictor effects.(ABSTRACT TRUNCATED AT 250 WORDS)
Pomegranate inhibits neuroinflammation and amyloidogenesis in IL-1β-stimulated SK-N-SH cells.
Velagapudi, Ravikanth; Baco, Gina; Khela, Sunjeet; Okorji, Uchechukwu; Olajide, Olumayokun
2016-06-01
Pomegranate fruit, Punica granatum L. (Punicaceae), and its constituents have been shown to inhibit inflammation. In this study, we aimed to assess the effects of freeze-dried pomegranate (PWE) on PGE2 production in IL-1β-stimulated SK-N-SH cells. An enzyme immunoassay (EIA) was used to measure prostaglandin E2 (PGE2) production from supernatants of IL-1β-stimulated SK-N-SH cells. Expression of COX-2, phospho-IκB, and phospho-IKK proteins was evaluated, while NF-κB reporter gene assay was carried out in TNFα-stimulated HEK293 cells to determine the effect of PWE on NF-κB transactivation. Levels of BACE-1 and Aβ in SK-N-SH cells stimulated with IL-1β were measured with an in cell ELISA. PWE (25-200 μg/ml) dose dependently reduced COX-2-dependent PGE2 production in SK-N-SH cells stimulated with IL-1β. Phosphorylation of IκB and IKK was significantly (p < 0.001) inhibited by PWE (50-200 μg/ml). Our studies also show that PWE (50-200 μg/ml) significantly (p < 0.01) inhibited NF-κB transactivation in TNFα-stimulated HEK293 cells. Furthermore, PWE inhibited BACE-1 and Aβ expression in SK-N-SH cells treated with IL-1β. Taken together, our study demonstrates that pomegranate inhibits inflammation, as well as amyloidogenesis in IL-1β-stimulated SK-N-SH cells. We propose that pomegranate is a potential nutritional strategy in slowing the progression of neurodegenerative disorders such as Alzheimer's disease.
Tani, Alessia; Anderloni, Giulia; Pierucci, Federica; Matteini, Francesca; Chellini, Flaminia; Zecchi Orlandini, Sandra; Meacci, Elisabetta
2014-01-01
Bone-marrow-derived mesenchymal stromal cells (MSCs) have the potential to significantly contribute to skeletal muscle healing through the secretion of paracrine factors that support proliferation and enhance participation of the endogenous muscle stem cells in the process of repair/regeneration. However, MSC-derived trophic molecules have been poorly characterized. The aim of this study was to investigate paracrine signaling effects of MSCs on skeletal myoblasts. It was found, using a biochemical and morphological approach that sphingosine 1-phosphate (S1P), a natural bioactive lipid exerting a broad range of muscle cell responses, is secreted by MSCs and represents an important factor by which these cells exert their stimulatory effects on C2C12 myoblast and satellite cell proliferation. Indeed, exposure to conditioned medium obtained from MSCs cultured in the presence of the selective sphingosine kinase inhibitor (iSK), blocked increased cell proliferation caused by the conditioned medium from untreated MSCs, and the addition of exogenous S1P in the conditioned medium from MSCs pre-treated with iSK further increased myoblast proliferation. Finally, we also demonstrated that the myoblast response to MSC-secreted vascular endothelial growth factor (VEGF) involves the release of S1P from C2C12 cells. Our data may have important implications in the optimization of cell-based strategies to promote skeletal muscle regeneration. PMID:25264785
Gueguinou, M; Crottès, D; Chantôme, A; Rapetti-Mauss, R; Potier-Cartereau, M; Clarysse, L; Girault, A; Fourbon, Y; Jézéquel, P; Guérin-Charbonnel, C; Fromont, G; Martin, P; Pellissier, B; Schiappa, R; Chamorey, E; Mignen, O; Uguen, A; Borgese, F; Vandier, C; Soriani, O
2017-06-22
The remodeling of calcium homeostasis contributes to the cancer hallmarks and the molecular mechanisms involved in calcium channel regulation in tumors remain to be characterized. Here, we report that SigmaR1, a stress-activated chaperone, is required to increase calcium influx by triggering the coupling between SK3, a Ca 2+ -activated K + channel (KCNN3) and the voltage-independent calcium channel Orai1. We show that SigmaR1 physically binds SK3 in BC cells. Inhibition of SigmaR1 activity, either by molecular silencing or by the use of sigma ligand (igmesine), decreased SK3 current and Ca 2+ entry in breast cancer (BC) and colorectal cancer (CRC) cells. Interestingly, SigmaR1 inhibition diminished SK3 and/or Orai1 levels in lipid nanodomains isolated from BC cells. Analyses of tissue microarray from CRC patients showed higher SigmaR1 expression levels in cancer samples and a correlation with tumor grade. Moreover, the exploration of a cohort of 4937 BC patients indicated that high expression of SigmaR1 and Orai1 channels was significantly correlated to a lower overall survival. As the SK3/Orai1 tandem drives invasive process in CRC and bone metastasis progression in BC, our results may inaugurate innovative therapeutic approaches targeting SigmaR1 to control the remodeling of Ca 2+ homeostasis in epithelial cancers.
Stathopoulos, Panos; Kumar, Aditya; Nowak, Richard J.; O’Connor, Kevin C.
2017-01-01
Myasthenia gravis (MG) is a B cell–mediated autoimmune disorder of neuromuscular transmission. Pathogenic autoantibodies to muscle-specific tyrosine kinase (MuSK) can be found in patients with MG who do not have detectable antibodies to the acetylcholine receptor (AChR). MuSK MG includes immunological and clinical features that are generally distinct from AChR MG, particularly regarding responsiveness to therapy. B cell depletion has been shown to affect a decline in serum autoantibodies and to induce sustained clinical improvement in the majority of MuSK MG patients. However, the duration of this benefit may be limited, as we observed disease relapse in MuSK MG patients who had achieved rituximab-induced remission. We investigated the mechanisms of such relapses by exploring autoantibody production in the reemerging B cell compartment. Autoantibody-expressing CD27+ B cells were observed within the reconstituted repertoire during relapse but not during remission or in controls. Using two complementary approaches, which included production of 108 unique human monoclonal recombinant immunoglobulins, we demonstrated that antibody-secreting CD27hiCD38hi B cells (plasmablasts) contribute to the production of MuSK autoantibodies during relapse. The autoantibodies displayed hallmarks of antigen-driven affinity maturation. These collective findings introduce potential mechanisms for understanding both MuSK autoantibody production and disease relapse following B cell depletion. PMID:28878127
The challenge of diagnosing seborrheic keratosis by reflectance confocal microscopy.
Guo, A; Chen, J; Yang, C; Ding, Y; Zeng, Q; Tan, L
2018-05-24
Seborrheic keratosis (SK) is one of the most common skin tumors seen by dermatologists. It should be differentiated with many diseases, especially skin tumors. Reflectance confocal microscopy (RCM) has been applied for evaluation of SK. There are a few studies that describe the RCM of SK. The aim of the study was to find the challenge of diagnosing seborrheic keratosis by reflectance confocal microscopy. A total of 390 patients with a clinical suspicious diagnosis of seborrheic keratosis were enrolled in this study, and lesions from each patient were imaged with RCM. Thirty-seven of these patients performed a biopsy in order to be given a histological diagnosis. We retrospectively analyzed the outcomes of RCM diagnosis and histological diagnosis, and then found the RCM characteristics of biopsy-proven lesions. According to RCM images, 258 of 390 (66.2%) patients were diagnosed with SK, 97 of 390 (24.9%) patients could not be diagnosed by the dermatologist according to RCM. Of all 37 biopsied lesions, 23 were SK, 6 were actinic keratosis, 2 were basal cell carcinoma, and 2 were squamous cell carcinoma. It is challenge to diagnose seborrheic keratosis by reflectance confocal microscopy. It may due to the variable clinical and RCM appearances of SK, and limited depth of RCM. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
On the partition dimension of comb product of path and complete graph
NASA Astrophysics Data System (ADS)
Darmaji, Alfarisi, Ridho
2017-08-01
For a vertex v of a connected graph G(V, E) with vertex set V(G), edge set E(G) and S ⊆ V(G). Given an ordered partition Π = {S1, S2, S3, …, Sk} of the vertex set V of G, the representation of a vertex v ∈ V with respect to Π is the vector r(v|Π) = (d(v, S1), d(v, S2), …, d(v, Sk)), where d(v, Sk) represents the distance between the vertex v and the set Sk and d(v, Sk) = min{d(v, x)|x ∈ Sk}. A partition Π of V(G) is a resolving partition if different vertices of G have distinct representations, i.e., for every pair of vertices u, v ∈ V(G), r(u|Π) ≠ r(v|Π). The minimum k of Π resolving partition is a partition dimension of G, denoted by pd(G). Finding the partition dimension of G is classified to be a NP-Hard problem. In this paper, we will show that the partition dimension of comb product of path and complete graph. The results show that comb product of complete grapph Km and path Pn namely p d (Km⊳Pn)=m where m ≥ 3 and n ≥ 2 and p d (Pn⊳Km)=m where m ≥ 3, n ≥ 2 and m ≥ n.
Anti-MuSK myasthenia gravis with prolonged remission.
Bouwyn, Jean Paul; Magnier, Patrick; Bédat-Millet, Anne-Laure; Ahtoy, Patrick; Maltête, David; Lefaucheur, Romain
2016-07-01
Myasthenia gravis (MG) with antibodies against muscle-specific tyrosine kinase (MuSK) is a rare disorder of neuromuscular transmission affecting preferentially bulbar, neck and respiratory muscles. We report the case of a 22-year-old man who presented with diplopia on lateral gaze to both sides, facial diplegia, nasal dysarthria and dysphagia. Repetitive nerve stimulation of the trapezius and orbicularis oculi muscles showed amplitude decrements of 19% and 41% respectively supporting the diagnosis of myasthenia gravis. MUsK antibodies were positive. Corticosteroids were introduced and then tapered and discontinued at 6 months after initiation. The patient remained in remission and asymptomatic for 4 years without ongoing treatment or prior treatment with rituximab after this first relapse of MuSK-MG. MuSK- MG is considered a hard-to-treat condition and patients generally remain dependent on immunosuppression or prior treatment with rituximab. Our observation highlights that patients with MuSK-MG can have a benign course and that continued immunosuppressive or immunomodulatory therapy may not always be required. Copyright © 2016 Elsevier B.V. All rights reserved.
Theory of the magnetic skyrmion glass
NASA Astrophysics Data System (ADS)
Hoshino, Shintaro; Nagaosa, Naoto
2018-01-01
Skyrmions and skyrmion crystal (SkX) discovered in chiral magnets show unique physical properties due to their nontrivial topology such as the stability against the annihilation and the motion driven by the ultralow current density, which can be advantageous for the device applications such as magnetic memories. Especially, the chiral dynamics, i.e., the velocity perpendicular to the force acting on a skyrmion, is a key to avoid the impurity potential and enhances its mobility. However, the collective pinning of SkX occurs by the disorder, which is crucial for its low energy properties. Here we study theoretically the low energy dynamics of SkX in the presence of disorder effects in terms of replica field theory, and reveal nonreciprocal collective modes and their electromagnetic responses along the direction of the external magnetic field. The physical quantities such as the relaxation rate of μ SR /NMR and the pinning frequency show a dramatic change associated with the topological phase transition from the helical state to SkX. These results provide a firm basis to explore the glassy state of SkX.
Pseudopropionibacterium sp. nov., a novel red-pigmented species isolated from human gingival sulcus.
Saito, Masanori; Shinozaki-Kuwahara, Noriko; Tsudukibashi, Osamu; Hashizume-Takizawa, Tomomi; Kobayashi, Ryoki; Kurita-Ochiai, Tomoko
2018-04-24
Strain SK-1 T is a novel Gram stain-positive, pleomorphic, rod-shaped, non-spore forming, and non-motile organism, designated SK-1 T , isolated from human gingival sulcus that produces acetic acid, propionic acid, lactic acid, and succinic acid as end products of glucose fermentation. Strain SK-1 T had the closest relatedness to Pseudopropionibacterium (Propionibacterium) propionicum with sequence homologies of the 16S rRNA and RNA polymerase β subunit (rpoB) genes of 96.6% and 93.1%, respectively. The genomic DNA G + C content of the isolate was 61.8 mol%. Based on the sequence data of the 16S rRNA and housekeeping (rpoB) genes, we propose a novel taxon, Pseudopropionibacterium rubrum sp. nov. (type strain SK-1 T = JCM 31317T= DSM 100122T). The 16S rRNA and rpoB gene sequences of strain SK-1 T were deposited to the DNA Data Bank of Japan under the accession numbers LC002971 and LC102236, respectively. © 2018 The Societies and John Wiley & Sons Australia, Ltd.
Zhu, Lin; Zhang, Yongshu; Fan, Jingyuan; Herzberg, Mark C.; Kreth, Jens
2010-01-01
Streptococcus sanguinis is an oral commensal bacterium and endogenous pathogen in the blood, which generally is naturally competent to take up extracellular DNA. Regarded as a stress response, competence development enables S. sanguinis to acquire new genetic material. The sequenced reference strain SK36 encodes and expresses the genes required for competence (com) and uptake of DNA. Isolated from blood cultures of a confirmed case of infective endocarditis, strain 133–79 encodes all necessary com genes but is not transformable under conditions permissive for competence development in SK36. Using synthetic competence-stimulating peptides (sCSP) based on sequences of SK36 and 133–79 comC, both strains developed competence at similar frequencies in cross-transformation experiments. Furthermore, downstream response pathways are similar in strains SK36 and 133–79 since platelet aggregation and biofilm formation appeared unaffected by CSP. Collectively, the data indicate that strains SK36 and 133–79 respond to CSP similarly, strongly suggesting that endogenous production or release of CSP from 133–79 is impaired. PMID:21375702
Zhu, L; Zhang, Y; Fan, J; Herzberg, M C; Kreth, J
2011-04-01
Streptococcus sanguinis is an oral commensal bacterium and endogenous pathogen in the blood, which is generally naturally competent to take up extracellular DNA. Regarded as a stress response, competence development enables S. sanguinis to acquire new genetic material. The sequenced reference strain SK36 encodes and expresses the genes required for competence (com) and uptake of DNA. Isolated from blood cultures of a confirmed case of infective endocarditis, strain 133-79 encodes all necessary com genes but is not transformable under conditions permissive for competence development in SK36. Using synthetic competence-stimulating peptides (sCSP) based on sequences of SK36 and 133-79 comC, both strains developed competence at similar frequencies in cross-transformation experiments. Furthermore, downstream response pathways are similar in strains SK36 and 133-79 because platelet aggregation and biofilm formation appeared unaffected by CSP. Collectively, the data indicate that strains SK36 and 133-79 respond to CSP similarly, strongly suggesting that endogenous production or release of CSP from 133-79 is impaired. © 2011 John Wiley & Sons A/S.
Han, Biao; Zhao, Wei; Xie, Xiaoping; Su, Yulong; Wang, Wei; Hu, Hui
2015-04-06
Modulating signal with polarization modulator (PolM) is the simplest method for polarization shift keying (PolSK) in free space optical communication. However, this method has an intrinsic drawback on degree of polarization (DOP) reduction for the existence of polarization mode dispersion (PMD) in PolM. In this work, we analyze this change of DOP and its influence on PolSK using coherency matrix. We demonstrate that the decrease of DOP after PolM will generate extra loss and bit error ratio (BER) for PolSK communication, while this loss and BER will aggravate with the increase of laser linewidth and PolM length. For a practical PolSK system, laser linewidth should be less than 0.008nm.
Study of pharmaceutical industrial problems
NASA Technical Reports Server (NTRS)
Pincus, J. H.
1979-01-01
The growth of a human colon carcinoma cell line (SK-CO-1) and its production of carcinoembryonic antigen (CEA) in monolayer culture and on single layers of glass beads in unit gravity were evaluated. The limitations of using a microsphere-cell growth system in unit gravity were identified and how these may be overcome in space was considered. The project had the following tasks: (1) growth of cultured human colon carcinoma cells on a monolayer and CEA production; (2) evaluation of CEA production and release by SK-CO-1 cells grown on glass beads; (3) evaluation of other microcarriers for growing SK-CO-1 cells and determination of the minimum amount of culture medium needed for cell growth; and (4) growth of SK-CO-1 cells on collagen monolayers and CEA production.
Image Understanding and Intelligent Parallel Systems
1991-05-09
a common user interface for the interactive , graphical manipulation of those histories, and...Circuits and Systems, August 1987. Yap, S.-K. and M.L. Scott, "PenGuin: A language for reactive graphical user interface programming," to appear, INTERACT , Cambridge, United Kingdom, 1990. 74 ...of up to a factor of 100 over single-workstation implementations. User interfaces to large multiprocessor computers are a difficult issue addressed
ERIC Educational Resources Information Center
DeJong, William; And Others
1992-01-01
Focus on the designated driver strategy by broadcasters and the alcohol industry deflects attention from other alcohol-related problems and the factors influencing underage alcohol consumption. Strategies should emphasize sobriety checkpoints, no sales to minors, advertising reform, and excise taxes on alcohol. (SK)
Removal of Volatile Organics from Humidified Air Streams by Absorption.
1987-12-01
Type Comments Activated Carbons: SK-4 nut shell LCL coconut shell WV-B coal base CT coconut shell Specialty Carbons: Graphpac graphitized carbon area...Capacity, g/g Percentage Sorbent ( virgin ) (treated)D Change SK-4 0.114 0.117 +2.6 Carbosieve S-11 0.195 0.180 -7.7 Spherocarb 0.149 0.151 +1.3 CT...and WV-B with respect to their adsorption capacities. CT and SK-4 are both coconut -derived carbons produced by the same manufacturer. Differences
Breast Cancer Therapy Using Antibody-Endostatin Fusion Proteins
2008-04-01
animal tumor and/or human xenograft models. Task 9. Anti-tumor activity in human tumor xenografts (Months 18 -24) Anti-tumor efficacy in human...breast cancer SK-BR-3 xenografts in SCID mice. SK-BR-3 was implanted on the flank of SCID mice.9 The treatment was repeated (shown below in Fig. 18 ...untreated group (p=0.0141) (Fig. 18 ). KEY RESEARCH ACCOMPLISHMENTS o Treatment of established SK-BR-3 xenografts in SCID mice with the αHER2
Bhibhatbhan, Arunee; Kline, Gregory; Vincent, Angela; Toth, Cory
2007-08-01
We report a young woman with the abrupt onset of infectious mononucleosis due to Epstein-Barr virus associated with a subsequent autoimmune form of diabetes mellitus and myasthenia gravis with anti-muscle-specific kinase (MuSK) antibodies. The simultaneous onset of these two autoimmune diseases preceded by a systemic viral illness supports a causal relationship between MuSK antibodies and myasthenia gravis and suggests the possibility of a viral trigger in some cases.
Logistics Study -- Shelter Stockage.
1979-11-01
Supplies such as paper cups, toilet tissue, sanitary napkins , commode 4 chemicals, etc., must be provided. 4 WATER REQUIREMENTS Potable water and its...PROPOSED SANITATION KITS ITEM UI SK-III SK-IV SK-V Container ea 1 1 1 * Toilet Tissue ro 5 10 10 Can Opener ea 1 1 - Sanitary Napkins ea 36 60 60 Water...34 3.3.5 Unit No. 5. -- One set of assembly instructions as delineated in Figure 4. -he instructions shall be printed in black or blue ink on a sheet
NASA Astrophysics Data System (ADS)
Xi, Dangpeng; Qu, Haiying; Shi, Zhongye; Wan, Xiaoqiao
2017-04-01
Songliao Basin is one of the biggest lacustrine systems in Asia during Cretaceous age. Widespread deposits in the basin are mainly composed of clastic sediments which contain abundant fossils including gastropod, bivalves, ostracods, vertebrates and others. These well preserved ostracod fossils provide us valuable information about past climate changes and biotic responses in a greenhouse environment.The Cretaceous Continental Scientific Drilling in the Songliao Basin (SK1) offers a rare opportunity to study Late Cretaceous non-marine ostracod. The SK1 was drilled separately in two boreholes: the lower 959.55-meter-thick south core (SK1(s)), and the upper 1636.72-meter-thick north core (SK1 (n)), containing the Upper Quantou, Qingshankou, Yaojia, Nenjiang Formation, Sifangtai, Mingshui and lower Taikang formations. Here we establish high-resolution non-marine ostracod biostratigraphy based on SK1. 80 species belonging to 12 genera in the SK1(S) and 45 species assigned to 20 genera in the SK1(n) have been recovered. Nineteen ostracod assemblage zones have been recognized: 1. Mongolocypris longicaudata-Cypridea Assemblage Zone, 2.Triangulicypris torsuosus-Triangulicypris torsuosus. nota Assemblage Zone, 3. Cypridea dekhoinensis-Cypridea gibbosa Assemblage Zone, 4.Cypridea nota-Sunliavia tumida Assemblage Zone, 5.Cypridea edentula-Lycopterocypris grandis Assemblage Zone, 6.Cypridea fuyuensis-Triangulicypris symmetrica Assemblage Zone, 7.Triangulicypris vestilus-Triangulicypris fusiformis-Triangulicypris pumilis Assemblage Zone, 8.Cypridea panda-Mongolocypris obscura Assemblage Zone, 9. Cypridea exornata-Cypridea dongfangensis Assemblage Zone, 10.Cypridea favosa-Mongolocypris tabulata Assemblage Zone, 11.Cypridea formosa-Cypridea sunghuajiangensis Assemblage Zone, 12. Cypridea anonyma-Candona fabiforma Assemblage Zone, 13.Cypridea gracila-Cypridea gunsulinensis Assemblage Zone, 14.Mongolocypris magna-Mongolocypris heiluntszianensis Assemblage Zone, 15.Cypridea liaukhenensis-Cypridea stellata Assemblage Zone, 16. Ilyocyprimorpha-Limnocypridea sunliaonensis-Periacanthella Assemblage Zone, 17. Strumosia inandita Asemblage-Zone, 18.Talicypridea amoena-Metacypris kaitunensis-Ziziphocypris simakovi Assemblage Zone, 19.Ilyocypris Assemblage Zone. Assemblage Zone 1 to 18 are belong to late Cretaceous, but 19 might constrained to the Latest Maastrichtian to the Earliset Danian.
SPS attitude control and stationkeeping: Requirements and tradeoffs
NASA Technical Reports Server (NTRS)
Oglevie, R. E.
1980-01-01
The dominant control requirements of solar power satellites change appreciably relative to small contemporary spacecraft. Trade studies and analyses illustrated preferred control approaches. It was found that the geosynchronous equatorial orbit is preferred over the alternative orbits considered, that the solar pressure orbit perturbation dominates stationkeeping propulsion requirements and that a combined AC and SK system using ion electric propulsion can satisfy the attitude control requirements. It was also found that control system/structural dynamic interaction stability can be obtained through frequency separation with reasonable structural dynamic requirements and simplify spacecraft design.
Connor, Carol McDonald; Day, Stephanie L.; Phillips, Beth; Sparapani, Nicole; Ingebrand, Sarah W.; McLean, Leigh; Barrus, Angela; Kaschak, Michael P.
2016-01-01
Many assume that cognitive and linguistic processes, such as semantic knowledge (SK) and self-regulation (SR) subserve learned skills like reading. However, complex models of interacting and bootstrapping effects of SK, SR, instruction, and reading hypothesize reciprocal effects. Testing this “lattice” model with children (n = 852) followed from 1st–2nd grade (5.9–10.4 years-of-age), revealed reciprocal effects for reading and SR, and reading and SK, but not SR and SK. More effective literacy instruction reduced reading stability over time. Findings elucidate the synergistic and reciprocal effects of learning to read on other important linguistic, self-regulatory, and cognitive processes, the value of using complex models of development to inform intervention design, and how learned skills may influence development during middle childhood. PMID:27264645
Bakeeva, Lora E.; Eldarov, Chupalav M.; Vangely, Irina M.; Kolosova, Nataliya G.; Vays, Valeriya B.
2016-01-01
Dry eye syndrome is an eye disorder affecting many people at an old age. Because dry eye syndrome is accelerated by aging, a useful approach to the prevention of this syndrome may be an intervention into the aging process. Previously, we showed that the mitochondria-targeted antioxidant SkQ1 delays manifestations of aging and inhibits the development of age-related diseases including dry eye syndrome. Nevertheless, the link between SkQ1's effects and its suppression of age-related changes in the lacrimal gland remains unclear. Here we demonstrated that dietary supplementation with SkQ1 (250 nmol/[kg body weight] daily) starting at age 1.5 months significantly alleviated the pathological changes in lacrimal glands of Wistar rats by age 24 months. By this age, lacrimal glands underwent dramatic deterioration of the ultrastructure that was indicative of irreversible disturbances in these glands' functioning. In contrast, in SkQ1-treated rats, the ultrastructure of the lacrimal gland was similar to that in much younger rats. Morphometric analysis of electron-microscopic specimens of lacrimal glands revealed the presence of numerous secretory granules in acinar cells and a significant increase in the number of operating intercalary ducts. Our results confirm that dietary supplementation with SkQ1 is a promising approach to healthy ageing and to prevention of aberrations in the lacrimal gland that underlie dry eye syndrome. PMID:27852065
Egorova, P A; Karelina, T V; Vlasova, O L; Antonov, S M; Besprozvanny, I B
2014-01-01
The effect of CyPPA, a positive modulator of small conductance calcium-activated potassium channels of type 3 and 2 (SK3/SK2), and of NS309, an activator of intermediate and small conductance calcium-activated potassium channels (IK/SK), on the activity of cerebellar Purkinje cells was studied in 2-month-old male mice. The use of 1 mM of CyPPA has led to a decrease of simple spike firing frequency in the discharge of Purkinje cells by 25%, on average, during 1 h after application. At the same time, application of 100 μM of NS309 has promoted a decrease in simple spike firing frequency by 47 %, on average, during 1 h after the beginning of the action. The obtained results confirm the hypothesis that SK channels participate in regulation of simple spike firing frequency in the discharge of Purkinje cells and are responsible for restriction of signal frequency. The effect of NS309 on simple spike firing frequency was more pronounced; therefore, the IK/SK channels may be suggested to play the cardinal role in regulation of spike activity of Purkinje cells. Since increasing simple spike frequency in the discharge of Purkinje cells is observed at many disturbances of motor activity, in particular, at spinocerebellar ataxia, it can be suggested that the studied compounds or substances of similar action are of interest as potential medicinal agents.
Contribution of Sialic Acid to the Voltage Dependence of Sodium Channel Gating
Bennett, Eric; Urcan, Mary S.; Tinkle, Sally S.; Koszowski, Adam G.; Levinson, Simon R.
1997-01-01
A potential role for sialic acid in the voltage-dependent gating of rat skeletal muscle sodium channels (rSkM1) was investigated using Chinese hamster ovary (CHO) cells stably transfected with rSkM1. Changes in the voltage dependence of channel gating were observed after enzymatic (neuraminidase) removal of sialic acid from cells expressing rSkM1 and through the expression of rSkM1 in a sialylation-deficient cell line (lec2). The steady-state half-activation voltages (Va) of channels under each condition of reduced sialylation were ∼10 mV more depolarized than control channels. The voltage dependence of the time constants of channel activation and inactivation were also shifted in the same direction and by a similar magnitude. In addition, recombinant deletion of likely glycosylation sites from the rSkM1 sequence resulted in mutant channels that gated at voltages up to 10 mV more positive than wild-type channels. Thus three independent means of reducing channel sialylation show very similar effects on the voltage dependence of channel gating. Finally, steady-state activation voltages for channels subjected to reduced sialylation conditions were much less sensitive to the effects of external calcium than those measured under control conditions, indicating that sialic acid directly contributes to the negative surface potential. These results are consistent with an electrostatic mechanism by which external, negatively charged sialic acid residues on rSkM1 alter the electric field sensed by channel gating elements. PMID:9089440
Li, Qintong; Cooper, Jeffrey J.; Altwerger, Gary H.; Feldkamp, Michael D.; Shea, Madeline A.; Price, David H.
2007-01-01
P-TEFb regulates eukaryotic gene expression at the level of transcription elongation, and is itself controlled by the reversible association of 7SK RNA and an RNA-binding protein HEXIM1 or HEXIM2. In an effort to determine the minimal region of 7SK needed to interact with HEXIM1 in vitro, we found that an oligo comprised of nucleotides 10–48 sufficed. A bid to further narrow down the minimal region of 7SK led to a surprising finding that HEXIM1 binds to double-stranded RNA in a sequence-independent manner. Both dsRNA and 7SK (10–48), but not dsDNA, competed efficiently with full-length 7SK for HEXIM1 binding in vitro. Upon binding dsRNA, a large conformational change was observed in HEXIM1 that allowed the recruitment and inhibition of P-TEFb. Both subcellular fractionation and immunofluorescence demonstrated that, while most HEXIM1 is found in the nucleus, a significant fraction is found in the cytoplasm. Immunoprecipitation experiments demonstrated that both nuclear and cytoplasmic HEXIM1 is associated with RNA. Interestingly, the one microRNA examined (mir-16) was found in HEXIM1 immunoprecipitates, while the small nuclear RNAs, U6 and U2, were not. Our study illuminates novel properties of HEXIM1 both in vitro and in vivo, and suggests that HEXIM1 may be involved in other nuclear and cytoplasmic processes besides controlling P-TEFb. PMID:17395637
Hossain, Md. Motarab; Banik, Naren L.; Ray, Swapan K.
2013-01-01
Malignant neuroblastomas mostly occur in children and are frequently associated with N-Myc amplification. Oncogene amplification, which is selective increase in copy number of the oncogene, provides survival advantages in solid tumors including malignant neuroblastoma. We have decreased expression of N-Myc oncogene using short hairpin RNA (shRNA) plasmid to increase anti-tumor efficacy of the isoflavonoid apigenin (APG) in human malignant neuroblastoma SK-N-DZ and SK-N-BE2 cell lines that harbor N-Myc amplification. N-Myc knockdown induced morphological and biochemical features of neuronal differentiation. Combination of N-Myc knockdown and APG most effectively induced morphological and biochemical features of apoptotic death. This combination therapy also prevented cell migration and decreased N-Myc driven survival, angiogenic, and invasive factors. Collectively, N-Myc knockdown and APG treatment is a promising strategy for controlling the growth of human malignant neuroblastoma cell lines that harbor N-Myc amplification. PMID:23941992
Hossain, Md Motarab; Banik, Naren L; Ray, Swapan K
2013-10-15
Malignant neuroblastomas mostly occur in children and are frequently associated with N-Myc amplification. Oncogene amplification, which is selective increase in copy number of the oncogene, provides survival advantages in solid tumors including malignant neuroblastoma. We have decreased expression of N-Myc oncogene using short hairpin RNA (shRNA) plasmid to increase anti-tumor efficacy of the isoflavonoid apigenin (APG) in human malignant neuroblastoma SK-N-DZ and SK-N-BE2 cell lines that harbor N-Myc amplification. N-Myc knockdown induced morphological and biochemical features of neuronal differentiation. Combination of N-Myc knockdown and APG most effectively induced morphological and biochemical features of apoptotic death. This combination therapy also prevented cell migration and decreased N-Myc driven survival, angiogenic, and invasive factors. Collectively, N-Myc knockdown and APG treatment is a promising strategy for controlling the growth of human malignant neuroblastoma cell lines that harbor N-Myc amplification. © 2013 Elsevier B.V. All rights reserved.
Performance investigation of optical multicast overlay system using orthogonal modulation format
NASA Astrophysics Data System (ADS)
Singh, Simranjit; Singh, Sukhbir; Kaur, Ramandeep; Kaler, R. S.
2015-03-01
We proposed a bandwidth efficient wavelength division multiplexed-passive optical network (WDM-PON) to simultaneously transmit 60 Gb/s unicast and 10 Gb/s multicast services with 10 Gb/s upstream. The differential phase shift keying (DPSK) multicast signal is superimposed onto multiplexed non-return to zero/polarization shift keying (NRZ/PolSK) orthogonal modulated data signals. Upstream amplitude shift keying (ASK) signals formed without use of any additional light source and superimposed onto received unicast NRZ/PolSK signal before being transmitted back to optical line terminal (OLT). We also investigated the proposed WDM-PON system for variable optical input power, transmission distance of single mode fiber in multicast enable and disable mode. The measured Quality factor for all unicast and multicast signal is in acceptable range (>6). The original contribution of this paper is to propose a bandwidth efficient WDM-PON system that could be projected even in high speed scenario at reduced channel spacing and expected to be more technical viable due to use of optical orthogonal modulation formats.
NASA Astrophysics Data System (ADS)
Shershnev, I. V.; Cherkasova, A. V.; Kopylov, A. S.; Glagolev, N. N.; Bragina, N. A.; Solov'eva, A. B.
2017-07-01
The immobilization of fluorinated tetraphenylporphyrins (FTPPs) into tetrafluoroethylene copolymers (fluoroplast F-42 and MF-4SK, a perfluorinated sulfonic acid cation exchanger in H+-form) is conducted in supercritical CO2 (scCO2). The effects the conditions of immobilization (the temperature and pressure of scCO2, reaction time, and the addition of cosolvents) and the structure of the carrier polymer have on the content of porphyrin in these polymers is studied. The porphyrin-loaded polymer systems are shown to exhibit photosensitizing activity in anthracene and cholesterol oxidation in scCO2. Under conditions of photocatalysis, chemical and functional stability is a feature of only MF-4SK polymer systems; this is attributed to the formation of protonated forms of the porphyrins and their interaction with SO3 --groups of the polymer (an ion exchange process), which prevents leaching of the FTPP from the polymer matrix. The photocatalytic process actually occurs inside the matrix of the perfluorinated copolymer, with the protonated form of the porphyrin acting as a photosensitizer. The rate constant of anthracene photooxidation in the presence of FTPP-loaded MF-4SK films in scCO2 is found to pass through a maximum as a function of the porphyrin content and the polymer film thickness. The use of such catalytic systems for cholesterol photooxidation in scCO2 is shown to produce a virtual monoproduct (yield, 10%): 6-formyl-B-norcholestane-3,5-diol, a compound with high biological activity.
Submonolayer Quantum Dot Infrared Photodetector
NASA Technical Reports Server (NTRS)
Ting, David Z.; Bandara, Sumith V.; Gunapala, Sarath D.; Chang, Yia-Chang
2010-01-01
A method has been developed for inserting submonolayer (SML) quantum dots (QDs) or SML QD stacks, instead of conventional Stranski-Krastanov (S-K) QDs, into the active region of intersubband photodetectors. A typical configuration would be InAs SML QDs embedded in thin layers of GaAs, surrounded by AlGaAs barriers. Here, the GaAs and the AlGaAs have nearly the same lattice constant, while InAs has a larger lattice constant. In QD infrared photodetector, the important quantization directions are in the plane perpendicular to the normal incidence radiation. In-plane quantization is what enables the absorption of normal incidence radiation. The height of the S-K QD controls the positions of the quantized energy levels, but is not critically important to the desired normal incidence absorption properties. The SML QD or SML QD stack configurations give more control of the structure grown, retains normal incidence absorption properties, and decreases the strain build-up to allow thicker active layers for higher quantum efficiency.
Firsov, Alexander M; Rybalkina, Irina G; Kotova, Elena A; Rokitskaya, Tatyana I; Tashlitsky, Vadim N; Korshunova, Galina A; Rybalkin, Sergei D; Antonenko, Yuri N
2018-02-01
The present study demonstrated for the first time the interaction between adenosine 3',5'-cyclic monophosphate (cAMP), one of the most important signaling compounds in living organisms, and the mitochondria-targeted antioxidant plastoquinonyl-decyltriphenylphosphonium (SkQ1). The data obtained on model liquid membranes and human platelets revealed the ability of SkQ1 to selectively transport cAMP, but not guanosine 3',5'-cyclic monophosphate (cGMP), across both artificial and natural membranes. In particular, SkQ1 elicited translocation of cAMP from the source to the receiving phase of a Pressman-type cell, while showing low activity with cGMP. Importantly, only conjugate with plastoquinone, but not dodecyl-triphenylphosphonium, was effective in carrying cAMP. In human platelets, SkQ1 also appeared to serve as a carrier of cAMP, but not cGMP, from outside to inside the cell, as measured by phosphorylation of the vasodilator stimulated phosphoprotein. The SkQ1-induced transfer of cAMP across the plasma membrane found here can be tentatively suggested to interfere with cAMP signaling pathways in living cells. Copyright © 2017 Elsevier B.V. All rights reserved.
Rodriguez-Vicente, J; Vicente-Ortega, V; Canteras-Jordana
1996-12-01
Chemotherapy for melanoma results in low response and must be reinforced with sensitizer compounds. We believed that azelaic acid (AZA) could modulate melanomas' resistance to antineoplastics. Therefore we tried to compare in vitro treatment with antineoplastics alone versus AZA treatment followed by antineoplastics. We carried out MTT assays to evaluate the cytotoxicity of melphalan, lomustine (CCNU), fotemustine, and 4-Hydroxyanisole (4-HA) on three melanoma lines (B16F10, SK-MEL-28, and SK-MEL-1), and the modulating effect of pretreatment with AZA (1 mM). AZA showed a dose-dependent antineoplastic activity on the three lines. Melphalan was the most active drug followed by CCNU, fotemustine, and 4-HA. The most sensitive line was B16F10 and the least sensitive was SK-meL-1. Previous treatment with AZA of B16F10 reinforced the effect of melphalan (2.5 times), CCNU (10 times), and fotemustine (14 times); whereas for SK-MEL-28 and SK-MEL-1, only the cytotoxicity of CCNU and fotemustine increased. An antagonist effect was produced by 4-HA on all three lines. We concluded that AZA enhances in vitro cytotoxicity of CCNU and fotemustine.
Seborrheic inclusion cyst of the skin positive for cytoplasmic inclusion bodies and HPV antigen.
Terada, Tadashi
2012-01-01
Seborrheic inclusion cyst (SIC) is a very rare variant of epidermal cyst of the skin. SIC shows seborrheic keratosis (SK)-like lesion in epidermal cyst. SIC is extremely rare; only 6 case reports have been published in the English literature. However, no immunohistochemical study of SIC has been reported. A 41-year-old Japanese man noticed a subcutaneous tumor in the neck. Physical examination showed slightly mobile tumor in the subcutaneous tissue, and total excision was performed. Grossly, the tumor (1 x 1 x 0.8 cm) was cyst containing atheromatous keratin. Microscopically, the lesion is a cyst containing keratins. About one half of the cyst showed features of epidermal cyst consisting of mature squamous epithelium with granular layers. The other one half showed SK-like epidermal proliferation. The SK-like area showed basaloid cell proliferation with pseudohorn cysts. No significant atypia was noted. Many eosinophilic cytoplasmic inclusion bodies were noted in the SK-like area. Immunohistochemically, the SK-like area was positive for pancytokeratin AE1/3, pancytokeratin CAM5.2, p63, and Ki-67 (labeling=8%) and HPV, but negative for p53. The pathological diagnosis was SIC.
77 FR 9698 - Notice of Extension of Concession Contracts
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-17
... Company, LLC. National Park. ROMO016-02 SK Horses, Ltd..... Rocky Mountain National Park. ROMO017-02.... ROMO028-02 SK Horses, Ltd..... Rocky Mountain National Park. ROMO030-02 Wild Basin Rocky Mountain...
Genetics Home Reference: pantothenate kinase-associated neurodegeneration
... Hayflick SJ, Westaway SK, Levinson B, Zhou B, Johnson MA, Ching KH, Gitschier J. Genetic, clinical, and ... on PubMed Zhou B, Westaway SK, Levinson B, Johnson MA, Gitschier J, Hayflick SJ. A novel pantothenate ...
Knowledge on musculoskeletal diseases by the Spanish population.
Lázaro, Pablo; Alfaro, Noelia; Méndez, José Ignacio; Garcia-Vicuña, Rosario; Jover, Juan Ángel; Sevilla, Jordi; Gabriele, Giovanna
2013-01-01
To explore knowledge on musculoskeletal-diseases (MSDs) by the Spanish population. This was a cross-sectional study of the general population (> 18 years) using a telephone survey of 1,009 subjects stratified by habitat size, age, sex, and geographic area. A structured questionnaire was used to collect information on the subjects, their general knowledge of MSDs (GK), their specific knowledge of particular MSDs (SK), and their knowledge of their social impact (KSI). Synthetic indicators of the level of knowledge were used to analyze, using univariate and multivariate models, variables associated to the level of knowledge. The KSI level ranges from medium-high (mean: 0.62 ± 0.16 out of 1), suggesting that most subjects recognize MSDs as disabling conditions which affect the ability to work and have a high personal and social cost. The GK level is intermediate (mean: 0.50 ± 0.17); 60% of subjects know something about MSDs, but 54% state that their information is poor/very poor. The SK level is low (mean: 0.18 ± 0.10), and there are some MSDs that are little known (lupus, spondylitis). Being male or retired or having a MSD is associated to a greater knowledge of MSDs. The Spanish population has a medium level of knowledge of the frequency and extent to which MSDs affect performance of activities by those who suffer them. They identify them adequately and have a GK of their symptoms, but have little information about them. The level of knowledge varies depending on social and demographic factors and on whether or not the subject has direct or indirect experience of what a MSD means. Copyright © 2012 Elsevier España, S.L. All rights reserved.
Sarcoidosis in a case of MuSK-positive myasthenia gravis.
Spengos, Konstantinos; Vassilopoulou, Sofia; Christou, Yiolanda; Manta, Panagiota
2008-11-01
Whereas the coexistence of different autoimmune or rheumatologic diseases with myasthenia gravis is well documented, the combination of myasthenia with sarcoidosis is extremely rare. There very few case reports of patients suffering from these two immune-mediated diseases. Nearly all had acetylcholine receptor antibodies. As far as we know myasthenia gravis with antibodies to muscle-specific tyrosine kinase-MuSK--has not been associated with any form of sarcoidosis. We present probably the first case of MuSK-positive myasthenia gravis with concurrent, asymptomatic pulmonary sarcoidosis.
Evaluation of cluster expansions and correlated one-body properties of nuclei
NASA Astrophysics Data System (ADS)
Moustakidis, Ch. C.; Massen, S. E.; Panos, C. P.; Grypeos, M. E.; Antonov, A. N.
2001-07-01
Three different cluster expansions for the evaluation of correlated one-body properties of s-p and s-d shell nuclei are compared. Harmonic oscillator wave functions and Jastrow-type correlations are used, while analytical expressions are obtained for the charge form factor, density distribution, and momentum distribution by truncating the expansions and using a standard Jastrow correlation function f. The harmonic oscillator parameter b and the correlation parameter β have been determined by a least-squares fit to the experimental charge form factors in each case. The information entropy of nuclei in position space (Sr) and momentum space (Sk) according to the three methods are also calculated. It is found that the larger the entropy sum, S=Sr+Sk (the net information content of the system), the smaller the values of χ2. This indicates that maximal S is a criterion of the quality of a given nuclear model, according to the maximum entropy principle. Only two exceptions to this rule, out of many cases examined, were found. Finally an analytic expression for the so-called ``healing'' or ``wound'' integrals is derived with the function f considered, for any state of the relative two-nucleon motion, and their values in certain cases are computed and compared.
Complete stable remission and autoantibody specificity in myasthenia gravis.
Baggi, Fulvio; Andreetta, Francesca; Maggi, Lorenzo; Confalonieri, Paolo; Morandi, Lucia; Salerno, Franco; Bernasconi, Pia; Montomoli, Cristina; Barberis, Massimo; Mantegazza, Renato; Antozzi, Carlo
2013-01-08
Patients with myasthenia gravis (MG) are subgrouped as acetylcholine receptor (AChR)-positive, muscle-specific kinase (MuSK)-positive, and AChR/MuSK-negative MG (or double negative [DN]) on the basis of autoantibody assay. We investigated the relationships between autoantibody specificity, main clinical features, and outcome of the disease, in particular the occurrence of complete stable remission (CSR), by means of a retrospective study on a cohort of 677 Italian patients with MG. A total of 517 (76%) patients with AChR-positive MG, 55 (8%) patients with MuSK-positive MG, and 105 (16%) patients with DN MG were included in the study. Kaplan-Meier and Cox proportional hazard regression analyses were used to evaluate associations between baseline characteristics, antibody specificity, and CSR. Clinical stage at onset and at maximal worsening was more severe for MuSK-positive patients: bulbar impairment at maximal worsening was found in 83.6% of MuSK-positive patients compared with 58.6% of AChR-positive patients and 43.8% of DN patients (p < 0.001). Baseline characteristics of AChR-positive and DN patients were similar. CSR was observed in 3.6% of MuSK-positive patients compared with 22.2% of AChR-positive and 21.9% of DN patients. In the whole MG cohort, onset before age 40 (hazard ratio [HR] = 1.96, 95% confidence interval [CI] 1.27-3.02, p = 0.002) and ocular and generalized clinical stages at maximal worsening were associated with CSR (ocular, HR = 8.05, 95% CI 1.88-34.53, p = 0.005; generalized, HR = 3.71, 95% CI 1.16-11.90, p = 0.023; bulbar, HR = 3.16, 95% CI 1.00-10.05, p = 0.051). MuSK antibodies identify a clinically distinguishable, more severe form of MG since the disease onset, with a lower occurrence of CSR. These features should be considered by the clinician in the management of this particular form of MG.
Huang, Chang-Yu; Wu, Guang-Jer
2016-04-01
Overexpression of METCAM/MUC18, an immunoglobulin-like cell-adhesion molecule, promotes tumorigenesis and progression of human breast cancer cells. We also observed an intriguing phenomenon that a high-expressing SK-BR-3 clone manifested a transient tumor suppression effect in vivo. The purpose of this study was to understand if this was caused by clonal variation, METCAM/MUC18-dosage effect, or the number of cells injected. Several G418-resistant clones of SK-BR-3, expressing different levels of METCAM/MUC18, were obtained for testing effects of human METCAM/MUC18 on in vitro motility, invasiveness, and anchorage-independent colony formation (in vitro tumorigenicity) and in vivo tumorigenesis in female Balb/C athymic nude mice. Tumor sections were made for histology and immunohistochemistry analyses, and tumor lysates for Western blot analysis to determine the effects of human METCAM/MUC18 expression on levels of various downstream effectors. METCAM/MUC18 promoted in vitro motility, invasiveness, and in vitro tumorigenicity of SK-BR-3 cells in a dosage-specific manner. Overexpression of METCAM/MUC18 could promote in vivo tumorigenesis of SK-BR-3 cells even when one tenth of the previously used cell number (5 × 10(5)) was injected and in vivo tumorigenesis of SK-BR-3 cells was directly proportional to the dosage of the protein. The previously observed transient tumor suppression effect from the same clone was no longer observed. The downstream effector, such as phospho-AKT/AKT ratio, was elevated in the tumors. Transient suppression observed previously in the clone was caused by injection of a high cell number (2 × 10(6)-5 × 10(6)). METCAM/MUC18 positively promotes tumorigenesis of SK-BR-3 cells by increasing the survival and proliferation pathway. Copyright © 2016. Published by Elsevier B.V.
Smith, Caroline J; Kenney, W Larry; Alexander, Lacy M
2013-04-01
Regional variation in sweating over the human body is widely recognized yet variation in vasomotor responses and mechanisms causing this variation remain unclear. This study aimed to explore the relation between regional sweating rates (RSR) and skin blood flow (SkBF) responses to thermal and pharmacological stimuli in young, healthy subjects. In nine subjects (23 ± 3 yr), intradermal microdialysis (MD) probes were inserted into the ventral forearm, abdomen, thigh, and lower back and perfused with lactated Ringer solution. RSR over each MD membrane were measured using ventilated capsules with a laser Doppler probe housed in each capsule for measurement of red cell flux (laser Doppler flux, LDF) as an index of SkBF. Subjects completed a whole body heating protocol to 1°C rise in oral temperature and an acetylcholine dose response (ACh 1 × 10(-7)-0.1 M; mean skin temperature 34°C). Maximal LDF were obtained at the end of both protocols (50 mM sodium nitroprusside).During heating RSR varied among sites (P < 0.0001) and was greater on the back versus other sites (P < 0.05), but LDF was similar between sites (P = 0.343). RSR and SkBF showed a strong relation during initial (arm: r = 0.77 ± 0.09, thigh: r = 0.81 ± 0.08, abdomen: r = 0.89 ± 0.04, back: r = 0.86 ± 0.04) but not latter stages of heating. No differences in RSR (P = 0.160) or SkBF (LDF, P = 0.841) were observed between sites during ACh perfusion. Taken together, these data suggest that increases in SkBF are necessary to initiate and increase sweating, but further rises in RSR are not fully dependent on SkBF in a dose-response manner. Furthermore, RSR cannot be explained by cholinergic sensitivity or variation in SkBF.
Cramer, Matthew N.; Gagnon, Daniel; Crandall, Craig G.; Jay, Ollie
2016-01-01
Attenuated skin blood flow (SkBF) is often assumed to impair core temperature (Tc) regulation. Profound pharmacologically-induced reductions in SkBF (~85%) lead to impaired sweating but whether the smaller attenuations in SkBF (~20%) more associated with ageing and certain diseases lead to decrements in sweating and maximum heat loss potential is unknown. Seven healthy males (28±4y) completed a 30-min equilibration period at 41°C and a vapour pressure (Pa) of 2.57 kPa followed by incremental steps in Pa of 0.17 kPa every 6-min to 5.95 kPa. Differences in heat loss potential were assessed by identifying the critical vapour pressure (Pcrit) at which an upward inflection in Tc occurred. Three separate treatments elicited changes in plasma volume to achieve three distinct levels of SkBF: control (CON), diuretic-induced iso-osmotic dehydration to lower SkBF (DEH), and continuous saline infusion to maintain SkBF (SAL). Tc, mean skin temperature (Tsk), heart rate, mean laser-Doppler flux (forearm, thigh; LDFmean), mean local sweat rate (forearm, thigh; LSRmean), and metabolic rate were measured. In DEH, a 14.2±5.7% lower plasma volume resulted in a ~20% lower LDFmean (DEH: 139±23, CON: 176±22, SAL: 186±22 PU; P=0.034). However, LSRmean and whole-body sweat losses were unaffected by treatment throughout (P>0.482). Pcrit for Tc was similar between treatments (CON: 5.05±0.30, DEH: 4.93±0.16, SAL: 5.12±0.10 kPa; P=0.166). Further, no differences were observed in the Tsk−Ta gradient, metabolic rate, or changes in Tc (P>0.197). In conclusion, a ~20% reduction in SkBF alters neither sweat rate nor the upper limit for heat loss from the skin during non-encapsulated passive heat stress. PMID:27859929
NASA Astrophysics Data System (ADS)
Graca, Bożena; Witek, Zbigniew; Burska, Dorota; Białkowska, Izabela; Łukawska-Matuszewska, Katarzyna; Bolałek, Jerzy
2006-12-01
In this paper the results of a study on the distribution of pore water phosphates and ammonia, and their fluxes under anoxic condition in a deep (> 70 m) accumulation-type bottom of the south-eastern Baltic Sea, namely in the Gdańsk Deep and the adjacent areas, are presented. All measurements were taken during the growth period, i.e. in September 2000, April 2001 and June 2002. Benthic phosphate and ammonia fluxes were estimated using Fick's First Law. Phosphate and ammonia concentrations ranged from 7.5 to 266.3 μmol dm - 3 and from 53.6 to 1248.3 μmol dm - 3 , respectively. The values recorded in the central part of the Gdańsk Deep were lower than those found both on its slopes and on the SW slope of the Gotland Deep. The lowest phosphate contents were typical of the Oblique Sill which separates the Gdańsk and Gotland Deeps. In 1993-2002, as a result of anoxia the sediments in the Gdańsk Deep released about 5.1 × 10 3 t P and 22.8 × 10 3 t N. These loads supplied on average 1.5% and 0.9% of phytoplankton's demand for P and N, respectively. In comparison to the total external load of nutrients discharged to the Gulf of Gdańsk (i.e. 8.79 × 10 3 t year - 1 P tot and 130.79 × 10 3 t year - 1 N tot; [Witek, Z., Humborg, Ch., Savchuk, O., Grelowski, A. and Łysiak-Pastuszak, E., 2003. Nitrogen and phosphorus budgets of the Gulf of Gdańsk (Baltic Sea). Est. Coast. Shelf Sci., 57:239-248.]), the return flux of P and N from the anoxic sediments to the water column in the Gdańsk Deep was a minor source of these elements.
The effect of ethnicity on the vascular responses to cold exposure of the extremities.
Maley, Matthew J; Eglin, Clare M; House, James R; Tipton, Michael J
2014-11-01
Cold injuries are more prevalent in individuals of African descent (AFD). Therefore, we investigated the effect of extremity cooling on skin blood flow (SkBF) and temperature (T sk) between ethnic groups. Thirty males [10 Caucasian (CAU), 10 Asian (ASN), 10 AFD] undertook three tests in 30 °C air whilst digit T sk and SkBF were measured: (i) vasomotor threshold (VT) test--arm immersed in 35 °C water progressively cooled to 10 °C and rewarmed to 35 °C to identify vasoconstriction and vasodilatation; (ii) cold-induced vasodilatation (CIVD) test--hand immersed in 8 °C water for 30 min followed by spontaneous warming; (iii) cold sensitivity (CS) test--foot immersed in 15 °C water for 2 min followed by spontaneous warming. Cold sensory thresholds of the forearm and finger were also assessed. In the VT test, vasoconstriction and vasodilatation occurred at a warmer finger T sk in AFD during cooling [21.2 (4.4) vs. 17.0 (3.1) °C, P = 0.034] and warming [22.0 (7.9) vs. 12.1 (4.1) °C, P = 0.002] compared with CAU. In the CIVD test, average SkBF during immersion was greater in CAU [42 (24) %] than ASN [25 (8) %, P = 0.036] and AFD [24 (13) %, P = 0.023]. Following immersion, SkBF was higher and rewarming faster in CAU [3.2 (0.4) °C min(-1)] compared with AFD [2.5 (0.7) °C min(-1), P = 0.037], but neither group differed from ASN [3.0 (0.6) °C min(-1)]. Responses to the CS test and cold sensory thresholds were similar between groups. AFD experienced a more intense protracted finger vasoconstriction than CAU during hand immersion, whilst ASN experienced an intermediate response. This greater sensitivity to cold may explain why AFD are more susceptible to cold injuries.
A X-Ray Diffraction Study of the Structure of Fluid Argon.
NASA Astrophysics Data System (ADS)
Yan, Kam-Leung
X-ray diffraction patterns of liquid argon were measured and analyzed at six thermodynamic states, all above the critical pressure. These states were on the isotherms T = 105.4K ((rho) = 1.43, 1.36, & 1.30 g/cm('3)) and T = 152.0K ((rho) = 1.30, 1.15, & 1.00 g/cm('3)), with pressures between 70 and 765 kg/cm('2). Samples of fluid argon confined in a beryllium cell were irradiated by monochromatized Mo x-radiation. The scattered intensities were detected with a NaI scintillation counter using step-scanning technique. A total resolution of 0.06(DEGREES) in the scattering plane allowed the scanning process to be performed in uniform step-increments of 0.125(DEGREES). Cooling of the Be cell was accomplished with a two-stage N(,2)-He cooling system. Static structure factors S(k) were obtained from the diffraction data. Refinement of these factors and determination of the radial distribution function g(r) were performed by iterative Fourier analysis. The efficacy of this method was exemplified by the overall improvement in the general form as well as the fine details of both functions. The principal features in S(k) and g(r) were located below k = 9 (ANGSTROM)('-1) and r = 16 (ANGSTROM), respectively. The first three maxima in S(k) were approximately at 1.98, 3.66, and 5.28 (ANGSTROM)('-1), respectively, and their respective averaged heights were 2.19, 1.23, and 1.07. In g(r), the positions of the first three coordinate shells were consistently at 3.37, 7.11, and 10.31 (ANGSTROM), respectively; their respective averaged magnitudes were 2.41, 1.20, and 1.07. Both functions were examined for their response to variations of (rho) and T. The main structures in both functions were found to be strongly dependent of the bulk density of the fluid, and relatively insensitive to temperature changes. g(r) for the state of (rho) = 1.43 g/cm('3) presently studied was compared with the results of computer simulation studies of Lennard-Jones fluids (Verlet 1968). The excellent overall agreement inferred from the comparison was apparently indicative of the appropriateness of the Lennard-Jones (6:12) potential as an effective pair potential for classical monatomic fluids. Anomalies in the form of subsidiary peaks were present in g(r) for four states of argon. These secondary features were observed at or near the first major minimum, in between the first two principal coordinate shells. Their position and degree of prominence exhibit little evidence of state-dependence. The triplet correlation function g(,3)(r,s,t) of argon was studied with the modified Kirkwood superposition approximation (Egelstaff et al 1969, 1971) which included a correction term H(r,s,t). The corresponding term of H(r,s,t) in momentum space, H(k),(' )has presently been calculated for argon at six thermodynamic states on the two said isotherms. The structure in(' )H(k) was apparent of a short range nature, and varied smoothly and continuously with the thermodynamic parameters of the fluid. The small -k behavior of(' )H(k) was indicative of the long range form of its real space transform. H(k)(' )for the state of (rho) = 1.08 g/cm('3) showed a substantial increase in the prominence of secondary features. Although no attempt has yet been made to examine the nature of this phenomenon, the implied increase in the significance of the pressure effect might conceivably be caused by the fact that this state was the closest to the critical point. The strong state-dependence of(' )H(k) supported the theoretical prediction that H(k)(' )(--->) 0 for all k as the critical point was approached.
NASA Astrophysics Data System (ADS)
Li, X.; Zhou, W.; Han, L.; Xi, W. J.; Crusoe, Garmondyu E.
2014-12-01
To probe into the pattern in which the excavation and loading process have on such factors as stress and displacement in neighboring regions of deep open pits, a mechanical unloading model in coal mining process and another model for the loading process are set up respectively. Besides, FLAC3D software is used to simulate dynamic excavating and loading process in open pits and record such data as the unbalanced stress, unloading strength and displacement fluctuations, which further serve as basis for studying the functional relationship about different mining heights and scope of influence using fitting method. The research results indicate that the unloading strength enhances with increasing mining depth in a linear fashion. In addition, a noticeable displacement circle takes shape around the stope, which would also extends with growing mining depth. As to waste loading, it brings about large-scale surface subsidence in neighboring regions, which follows a logarithm function convergence pattern with the distance away from the dump border. Under combined effects of excavation and loading, the value of the soil mass displacement would increase with growing mining depth and loading height. Specifically, the soil displacement at a distance of 100 m away from the stope border (around 200 m away from the outer dump border) is abnormally significant and it further develops at a rate of 0.0228 mm/h. W celu zbadania zależności pomiędzy procesami wydobycia i składowania urobku a takimi czynnikami jak naprężenia i przemieszczenia w sąsiadujących partiach głębokich wyrobisk odkrywkowych, wykorzystano model mechaniczny procesu urabiania węgla oraz model procesu jego składowania. Wykorzystano oprogramowanie FLAC 3D do symulacji procesów wydobycia i składowania w wyrobiskach odkrywkowych, zapisano odpowiednie dane: niezrównoważone naprężenia, wytrzymałość w trakcie odciążania oraz wahania przemieszczeń gruntu, które wykorzystane zostały następnie jako podstawa do badania funkcjonalnych zależności pomiędzy wysokością poziomu wydobycia a skalą oddziaływania, przy użyciu odpowiednich metod dopasowania. Wyniki badań wskazują, że wytrzymałość w trakcie odciążania wzrasta liniowo z głębokością. Ponadto, zarejestrowano wyraźny kołowy przebieg przemieszczenia wokół zbocza, który także rośnie z głębokością. W przypadku obciążenia wskutek urobku odpadowego, zanotowano obniżenia terenu o dużym zasięgu o przebiegu konwergencji opisanym funkcją logarytmiczną odległości od miejsca składowania urobku odpadowego. W przypadku wystąpienia połączonych efektów wydobycia i składowania, wielkość przemieszczeń mas gruntu wzrastać będzie wraz z głębokością prowadzenia prac i wysokością składowania. Przemieszczenie gruntu w odległości 100 m od brzegu wyrobiska (ok. 200 od zewnętrznej granicy składowiska) okazuje się niepokojąco duże i postępujące w tempie 0.0228 mm/h).
Connor, Carol McDonald; Day, Stephanie L; Phillips, Beth; Sparapani, Nicole; Ingebrand, Sarah W; McLean, Leigh; Barrus, Angela; Kaschak, Michael P
2016-11-01
Many assume that cognitive and linguistic processes, such as semantic knowledge (SK) and self-regulation (SR), subserve learned skills like reading. However, complex models of interacting and bootstrapping effects of SK, SR, instruction, and reading hypothesize reciprocal effects. Testing this "lattice" model with children (n = 852) followed from first to second grade (5.9-10.4 years of age) revealed reciprocal effects for reading and SR, and reading and SK, but not SR and SK. More effective literacy instruction reduced reading stability over time. Findings elucidate the synergistic and reciprocal effects of learning to read on other important linguistic, self-regulatory, and cognitive processes; the value of using complex models of development to inform intervention design; and how learned skills may influence development during middle childhood. © 2016 The Authors. Child Development © 2016 Society for Research in Child Development, Inc.
Development of novel Alicyclobacillus spp. isolation medium.
Chang, S; Kang, D-H
2005-01-01
To develop a new isolation medium with higher recovery rates of Alicyclobacillus spp. SK agar was developed with optimized incubation temperature, pH, acidulant, Tween 80 concentration and divalent cation addition. Results indicate that detection of Alicyclobacillus spp. by SK agar was significantly higher (P > 0.05) than those obtained by K agar, orange serum agar, and potato dextrose agar. Current media used for Alicyclobacillus spp. isolation still resulted in high numbers of false negative products. The sensitivity of SK agar to Alicyclobacillus spp. allows detection of low numbers of Alicyclobacillus spp. and also provides a more higher isolation results compared with currently used media. SK agar will be useful to the fruit juice industry to obtain more accurate numbers of contaminant Alicyclobacillus spp. With this media, false negative samples can be reduced, and the likelihood of exported products being rejected can be greatly reduced.
SkData: data sets and algorithm evaluation protocols in Python
NASA Astrophysics Data System (ADS)
Bergstra, James; Pinto, Nicolas; Cox, David D.
2015-01-01
Machine learning benchmark data sets come in all shapes and sizes, whereas classification algorithms assume sanitized input, such as (x, y) pairs with vector-valued input x and integer class label y. Researchers and practitioners know all too well how tedious it can be to get from the URL of a new data set to a NumPy ndarray suitable for e.g. pandas or sklearn. The SkData library handles that work for a growing number of benchmark data sets (small and large) so that one-off in-house scripts for downloading and parsing data sets can be replaced with library code that is reliable, community-tested, and documented. The SkData library also introduces an open-ended formalization of training and testing protocols that facilitates direct comparison with published research. This paper describes the usage and architecture of the SkData library.
Yao, Huili; Rui, Huan; Kumar, Ritesh; Eshelman, Kate; Lovell, Scott; Battaile, Kevin P.; Im, Wonpil; Rivera, Mario
2015-01-01
X-ray crystallography, molecular dynamics (MD) simulations and biochemistry were utilized to investigate the effect of introducing hydrophobic interactions in the 4-fold (N148L and Q151L) and B-pores (D34F) of Pseudomonas aeruginosa bacterioferritin B (BfrB) on BfrB function. The structures show only local structural perturbations and confirm the anticipated hydrophobic interactions. Surprisingly, structures obtained after soaking crystals in Fe2+-containing crystallization solution revealed that although iron loads into the ferroxidase centers of the mutants, the side chains of ferroxidase ligands E51 and H130 do not reorganize to bind the iron ions, as is seen in the wt BfrB structures. Similar experiments with a double mutant (C89S/K96C) prepared to introduce changes outside the pores show competent ferroxidase centers that function akin to those in wt BfrB. MD simulations comparing wt BfrB with the D34F and N148L mutants show that the mutants exhibit significantly reduced flexibility, and reveal a network of concerted motions linking ferroxidase centers and 4-fold and B-pores, which are important for imparting ferroxidase centers in BfrB with the required flexibility to function efficiently. In agreement, the efficiency of Fe2+ oxidation and uptake of the 4-fold and B-pore mutants in solution is significantly compromised relative to wt or C89S/K96C BfrB. Finally, our structures show a large number of previously unknown iron binding sites in the interior cavity and B-pores of BfrB, which reveal in unprecedented detail conduits followed by iron and phosphate ions across the BfrB shell, as well as paths in the interior cavity that may facilitate nucleation of the iron phosphate mineral. PMID:25640193
DOE Office of Scientific and Technical Information (OSTI.GOV)
Evans, C. J.; Hainich, R.; Oskinova, L. M.
Sk 183 is the visually brightest star in the N90 nebula, a young star-forming region in the Wing of the Small Magellanic Cloud (SMC). We present new optical spectroscopy from the Very Large Telescope which reveals Sk 183 to be one of the most massive O-type stars in the SMC. Classified as an O3-type dwarf on the basis of its nitrogen spectrum, the star also displays broadened He I absorption, which suggests a later type. We propose that Sk 183 has a composite spectrum and that it is similar to another star in the SMC, MPG 324. This brings themore » number of rare O2- and O3-type stars known in the whole of the SMC to a mere four. We estimate physical parameters for Sk 183 from analysis of its spectrum. For a single-star model, we estimate an effective temperature of 46 {+-} 2 kK, a low mass-loss rate of {approx}10{sup -7} M{sub Sun} yr{sup -1}, and a spectroscopic mass of 46{sup +9}{sub -8} M{sub Sun} (for an adopted distance modulus of 18.7 mag to the young population in the SMC Wing). An illustrative binary model requires a slightly hotter temperature ({approx}47.5 kK) for the primary component. In either scenario, Sk 183 is the earliest-type star known in N90 and will therefore be the dominant source of hydrogen-ionizing photons. This suggests Sk 183 is the primary influence on the star formation along the inner edge of the nebula.« less
Atchley, Derek; Hankosky, Emily R.; Gasparotto, Kaylyn; Rosenkranz, J. Amiel
2012-01-01
Repeated stress impacts emotion, and can induce mood and anxiety disorders. These disorders are characterized by imbalance of emotional responses. The amygdala is fundamental in expression of emotion, and is hyperactive in many patients with mood or anxiety disorders. Stress also leads to hyperactivity of the amygdala in humans. In rodent studies, repeated stress causes hyperactivity of the amygdala, and increases fear conditioning behavior that is mediated by the basolateral amygdala (BLA). Calcium-activated potassium (KCa) channels regulate BLA neuronal activity, and evidence suggests reduced small conductance KCa (SK) channel function in male rats exposed to repeated stress. Pharmacological enhancement of SK channels reverses the BLA neuronal hyperexcitability caused by repeated stress. However, it is not known if pharmacological targeting of SK channels can repair the effects of repeated stress on amygdala-dependent behaviors. The purpose of this study was to test whether enhancement of SK channel function reverses the effects of repeated restraint on BLA-dependent auditory fear conditioning. We found that repeated restraint stress increased the expression of cued conditioned fear in male rats. However, 1-EBIO (1 or 10 mg/kg) or CyPPA (5 mg/kg) administered 30 minutes prior to testing of fear expression brought conditioned freezing to control levels, with little impact on fear expression in control handled rats. These results demonstrate that enhancement of SK channel function can reduce the abnormalities of BLA-dependent fear memory caused by repeated stress. Furthermore, this indicates that pharmacological targeting of SK channels may provide a novel target for alleviation of psychiatric symptoms associated with amygdala hyperactivity. PMID:22487247
Singh, Sandeep; Davis, Rebecca; Alamanda, Vignesh; Pireddu, Roberta; Pernazza, Daniel; Sebti, Said; Lawrence, Nicholas; Chellappan, Srikumar
2010-01-01
Metastatic melanoma is an aggressive cancer with very low response rate against conventional chemotherapeutic agents such as dacarbazine (DTIC). Inhibitor of Rb-Raf-1 interaction (RRD-251) was tested against the melanoma cell lines SK-MEL-28, SK-MEL-5 and SK-MEL-2. RRD-251 was found to be a potent inhibitor of melanoma cell proliferation, irrespective of V600E B-Raf mutation status of the cell lines. In a SK-MEL-28 xenograft experiment, RRD-251 exerted a significant suppression of tumor growth compared to vehicle (p=0.003). Similar to in vitro effects, tumors from RRD-251 treated animals showed decreased Rb-Raf-1 interaction in vivo. Growth suppressive effects of RRD-251 were associated with induction of apoptosis as well as a G1 arrest, with an accompanying decrease in S-phase cells. RRD-251 inhibited Rb phosphorylation, and downregulated E2F1 protein levels in these cells. Real-time PCR analysis showed that RRD-251 caused downregulation of cell cycle regulatory genes thymidylate synthase (TS) and cdc6 as well as anti-apoptotic gene Mcl-1. Combinatorial treatment of RRD-251 and DTIC resulted in a significantly higher apoptosis in DTIC resistant cell lines SK-MEL-28 and SK-MEL-5, as revealed by increased Caspase-3 activity and PARP cleavage. Since aberrant Rb/E2F pathway is associated with melanoma progression and resistance to apoptosis, these results suggest that the Rb-Raf-1 inhibitor could be an effective agent for melanoma treatment, either alone or in combination with DTIC. PMID:21139044
Singh, Sandeep; Davis, Rebecca; Alamanda, Vignesh; Pireddu, Roberta; Pernazza, Daniel; Sebti, Said; Lawrence, Nicholas; Chellappan, Srikumar
2010-12-01
Metastatic melanoma is an aggressive cancer with very low response rate against conventional chemotherapeutic agents such as dacarbazine (DTIC). Inhibitor of Rb-Raf-1 interaction RRD-251 was tested against the melanoma cell lines SK-MEL-28, SK-MEL-5, and SK-MEL-2. RRD-251 was found to be a potent inhibitor of melanoma cell proliferation, irrespective of V600E B-Raf mutation status of the cell lines. In a SK-MEL-28 xenograft experiment, RRD-251 exerted a significant suppression of tumor growth compared with vehicle (P = 0.003). Similar to in vitro effects, tumors from RRD-251-treated animals showed decreased Rb-Raf-1 interaction in vivo. Growth suppressive effects of RRD-251 were associated with induction of apoptosis as well as a G(1) arrest, with an accompanying decrease in S-phase cells. RRD-251 inhibited Rb phosphorylation and downregulated E2F1 protein levels in these cells. Real-time PCR analysis showed that RRD-251 caused downregulation of cell-cycle regulatory genes thymidylate synthase (TS) and cdc6 as well as the antiapoptotic gene Mcl-1. Combinatorial treatment of RRD-251 and DTIC resulted in a significantly higher apoptosis in DTIC resistant cell lines SK-MEL-28 and SK-MEL-5, as revealed by increased caspase-3 activity and PARP cleavage. Because aberrant Rb/E2F pathway is associated with melanoma progression and resistance to apoptosis, these results suggest that the Rb-Raf-1 inhibitor could be an effective agent for melanoma treatment, either alone or in combination with DTIC. ©2010 AACR.
Bioactive nitric oxide concentration does not increase during reactive hyperemia in human skin.
Zhao, J L; Pergola, P E; Roman, L J; Kellogg, D L
2004-02-01
This study examined whether nitric oxide (NO) is involved in the cutaneous response to reactive hyperemia (RH) in the human forearm. We enrolled seven healthy volunteers. NO concentrations were monitored using a NO selective amperometric electrode (ISO-NOP200, World Precision Instruments) inserted into the skin of the forearm. Laser-Doppler flowmetry (Moor Instruments) was used for monitoring skin blood flow (SkBF) at the same site. SkBF and NO levels were monitored and recorded continuously throughout the experiment. An intradermal microdialysis probe was inserted adjacent to the NO electrode for drug delivery. Data collection began 140 min after the NO electrodes and microdialysis probes were inserted. RH was achieved by the inflation of a blood pressure cuff to 25 mmHg above systolic pressure for 7 min after which the pressure in the cuff was abruptly released. Acetylcholine (ACh) was given by microdialysis probe at the end of RH study to verify the ability of the electrode system to detect changes in the NO concentration. SkBF and NO data before RH and immediately, 2, 5, 7, and 10 min after cuff deflation were used for analysis. SkBF increased immediately after release of the occlusion (P < 0.0001) and remained elevated for 2 min. No significant NO changes occurred with the increases in LDF. ACh induced increases in both SkBF and NO (P < 0.000 and P < 0.037, respectively). We conclude that RH increases SkBF by mechanisms that do not require a measurable increase in NO concentrations.
A Rare Early-type Star Revealed in the Wing of the Small Magellanic Cloud
NASA Astrophysics Data System (ADS)
Evans, C. J.; Hainich, R.; Oskinova, L. M.; Gallagher, J. S., III; Chu, Y.-H.; Gruendl, R. A.; Hamann, W.-R.; Hénault-Brunet, V.; Todt, H.
2012-07-01
Sk 183 is the visually brightest star in the N90 nebula, a young star-forming region in the Wing of the Small Magellanic Cloud (SMC). We present new optical spectroscopy from the Very Large Telescope which reveals Sk 183 to be one of the most massive O-type stars in the SMC. Classified as an O3-type dwarf on the basis of its nitrogen spectrum, the star also displays broadened He I absorption, which suggests a later type. We propose that Sk 183 has a composite spectrum and that it is similar to another star in the SMC, MPG 324. This brings the number of rare O2- and O3-type stars known in the whole of the SMC to a mere four. We estimate physical parameters for Sk 183 from analysis of its spectrum. For a single-star model, we estimate an effective temperature of 46 ± 2 kK, a low mass-loss rate of ~10-7 M ⊙ yr-1, and a spectroscopic mass of 46+9 -8 M ⊙ (for an adopted distance modulus of 18.7 mag to the young population in the SMC Wing). An illustrative binary model requires a slightly hotter temperature (~47.5 kK) for the primary component. In either scenario, Sk 183 is the earliest-type star known in N90 and will therefore be the dominant source of hydrogen-ionizing photons. This suggests Sk 183 is the primary influence on the star formation along the inner edge of the nebula.
Kim, Won-Jeong; Lee, Won-Ku; Song, Margaret; Kim, Hoon-Soo; Ko, Hyun-Chang; Kim, Byung-Soo; Kim, Moon-Bum
2015-04-01
Sometimes the clinical differentiation between verruca plana (VP) and VP-like seborrheic keratosis (SK) could be challenged. However, there have been no studies on this issue to date. The aim of this study was to elucidate clinical and dermoscopic differences between these two diseases, and also to suggest a diagnostic algorithm of VP and VP-like SK without skin biopsy. The patients who had lesions clinically considered as VP or VP-like SK were the target of our study. We took clinical and dermoscopic photos with informed consent and conducted a questionnaire. All patients had their diagnoses confirmed by biopsy. Thirty-three patients were enrolled in our study. Seventeen patients were finally diagnosed with VP (51.5%) and 16 patients with VP-like SK (48.5%). In clinical findings, VP-like SK showed significantly more scattered distribution than VP (P = 0.039), which exhibited more clustered or grouped distribution (P = 0.039). In dermoscopic findings, brain-like appearance was more commonly observed in VP-like SK (P = 0.003) whereas VP showed more red dots or globular vessels (P = 0.017) and even-colored light brown to yellow patch (P < 0.001). Sex, onset age, the size of each lesion, location, color and shape showed no significant differences between them (P > 0.05). Based on our results, we suggest a diagnostic algorithm using Koebner's phenomenon, dermoscopic findings, distribution of each lesion and biopsy for multiple VP-like lesions in adults, and we think it will be a very useful diagnostic tool in daily clinical dermatological practice. © 2015 Japanese Dermatological Association.
Rodriguez-Vicente, J; Vicente-Ortega, V; Canteras-Jordana, M; Calderon-Rubiales, F
1997-10-01
We studied the response of mouse B16F10 and SK-MEL-28 and SK-MEL-1 human melanoma cell lines to treatment with 4-hydroxyanisole (4-HA), and attempted to relate the response to the dopa oxidase levels and the morphological characteristics of each cell line. Clear dose-response curves were observed after 24 h of treatment in each cell line, the 4-HA being more toxic to the B16F10 cells, with an ID50 value of 215 microM. This was much lower than that observed for the SK-MEL-28 and SK-MEL-1 cell lines (ID50 of 5.98 mM and 7.17 mM, respectively). There was a direct relationship between toxicity levels and dopa oxidase activity, since the highest specific activity was obtained for B16F10 (15.9 mU), while lower activity was registered for SK-MEL-28 (4.59 mU) and SK-MEL-1 (1.24 mU), which also showed lower 4-HA toxicity. Morphologically, we observed the typical characteristics of cellular injury, with swelling and dilation of the internal membranes and organelles, an increased number of vacuoles, and an increased number of abnormal multilamellar melanosomes or thick clumps of irregularly distributed melanin. On the other hand, we observed that the two cell lines with the lowest dopa oxidase activity contained more mature fully melanized melanosomes than B16F10, pointing to possible alterations in the melanosome transference mechanism and lower enzymatic activity in the mature melanosomes of these two human cell lines.
Utter, Alan C; Lambeth, Pamela G
2010-02-01
To evaluate the accuracy of multifrequency bioelectrical impedance analysis (MFBIA) in assessing fat-free mass (FFM) in comparison with hydrostatic weighing (HW) and skinfolds (SK) in high school wrestlers in a hydrated state. Body composition was determined by MFBIA, HW, and three-site SK in 72 high school wrestlers (mean +/- SD; age = 15.3 +/- 1.4 yr, height = 1.71 +/- 0.08 m, body mass = 67.3 +/- 13.4 kg). Hydration state was quantified by evaluating urine specific gravity. There were no significant differences for estimated FFM between MFBIA (57.2 +/- 9.5 kg) and HW (57.0 +/- 10.1 kg) or SK (56.4 +/- 8.8 kg). The SEE for FFM with HW as the reference method were 2.73 kg for MFBIA and 2.66 kg for SK. Correlations were found for FFM between HW and MFBIA (r = 0.96, P < 0.001) and between HW and SK (r = 0.97, P < 0.001). A systematic bias was found for MFBIA because the difference between MFBIA and HW correlated with the FFM average of the two methods (r = -0.22, P < 0.001). A bias was also seen between SK and HW and correlated with the FFM average (r = -0.47, P < 0.001). This study demonstrates that MFBIA provides similar estimates of FFM when compared with HW in a heterogeneous high school wrestling population during a hydrated state. MFBIA is an attractive assessment tool, easy to use, and may be considered as an alternative field-based method of estimating the FFM of high school wrestlers.
Aoki, Ken; Stephens, Dan P; Zhao, Kun; Kosiba, Wojciech A; Johnson, John M
2006-09-01
In humans, the nocturnal fall in internal temperature is associated with increased endogenous melatonin and with a shift in the thermoregulatory control of skin blood flow (SkBF), suggesting a role for melatonin in the control of SkBF. The purpose of this study was to test whether daytime exogenous melatonin would shift control of SkBF to lower internal temperatures during heat stress, as is seen at night. Healthy male subjects (n = 8) underwent body heating with melatonin administration (Mel) or without (control), in random order at least 1 wk apart. SkBF was monitored at sites pretreated with bretylium to block vasoconstrictor nerve function and at untreated sites. Cutaneous vascular conductance, calculated from SkBF and arterial pressure, sweating rate (SR), and heart rate (HR) were monitored. Skin temperature was elevated to 38 degrees C for 35-50 min. Baseline esophageal temperature (Tes) was lower in Mel than in control (P < 0.01). The Tes threshold for cutaneous vasodilation and the slope of cutaneous vascular conductance with respect to Tes were also lower in Mel at both untreated and bretylium-treated sites (P < 0.05). The Tes threshold for the onset of sweating and the Tes for a standard HR were reduced in Mel. The slope of the relationship of HR, but not SR, to Tes was lower in Mel (P < 0.05). These findings suggest that melatonin affects the thermoregulatory control of SkBF during hyperthermia via the cutaneous active vasodilator system. Because control of SR and HR are also modified, a central action of melatonin is suggested.
Li, Yue; Hu, Hongxiang; Butterworth, Michael B; Tian, Jin-Bin; Zhu, Michael X; O'Neil, Roger G
2016-01-01
The voltage- and Ca2+-activated, large conductance K+ channel (BK, maxi-K) is expressed in the collecting duct system of kidney where it underlies flow- and Ca2+-dependent K+ excretion. To determine if other Ca2+-activated K+ channels (KCa) may participate in this process, mouse kidney and the K+-secreting mouse cortical collecting duct (CCD) cell line, mCCDcl1, were assessed for TRPV4 and KCa channel expression and cross-talk. qPCR mRNA analysis and immunocytochemical staining demonstrated TRPV4 and KCa expression in mCCDcl1 cells and kidney connecting tubule (CNT) and CCD. Three subfamilies of KCa channels were revealed: the high Ca2+-binding affinity small-conductance SK channels, SK1and SK3, the intermediate conductance channel, IK1, and the low Ca2+-binding affinity, BK channel (BKα subunit). Apparent expression levels varied in CNT/CCD where analysis of CCD principal cells (PC) and intercalated cells (IC) demonstrated differential staining: SK1:PC
NASA Astrophysics Data System (ADS)
Işıklan, Muhammet; Yıldırım, Erdem Kamil; Atiş, Murat; Sonkaya, Ömer; Çoşut, Bünyemin
2016-08-01
In this study a new monospirocyclic phosphazene derivative, 4‧,4‧,6‧,6‧-tetrachloro-3-(2-methoxyethyl)-3H,4H-spiro [1,3,2-benzoxazaphosphinine-2,2‧- [1,3,5,2,4,6] triazatriphosphinine] (SP1) was synthesized from the reaction of hexachlorocyclotriphosphazene (N3P3Cl6) with N/O donor-type, 2-{[(2-Metoxyethyl) amino]methyl}phenol. The structural investigations of the compound were verified by elemental analyses, MS, FTIR, 1H, 13C, 31P NMR spectroscopy and the single crystal X-ray diffraction analysis. The structural and spectroscopic data of the molecule in the ground state were calculated by using density functional method (DFT) using 6-311++G (d, p) basis set. The complete assignments of all vibrational modes were performed on the basis of the total energy distributions (TED). Isotropic chemical shifts (31P, 1H and 13C NMR) were calculated using the gauge-invariant atomic orbital (GIAO) method. Theoretical calculations of bond parameters, harmonic vibration frequencies and nuclear magnetic resonance are in good agreement with experimental results. The electrophilic and nucleophilic attack centers in SP1 were predicted with the local softness values (sk+, and sk-) of individual atoms and it is confirmed that P atoms of the PCl2 groups are nucleophilic attack centers.
The Crisis of Education in Arkhangel'sk.
ERIC Educational Resources Information Center
Konstantinov, A. S.
1995-01-01
Asserts that there is an educational crisis in the Arkhangel'sk area of Russia. Summarizes research studies of students and teachers to illustrate low teacher morale, student dissatisfaction, and low pay for all educators. Argues for financial autonomy for educational institutions. (CFR)
Pelucchi, Bruna; Grimaldi, Annalisa; Moriondo, Andrea
2008-01-01
In salamander rods, Ca(2+)-activated K(+) current (I(KCa)) provides an effective "clamp" of the dark membrane potential to its normal resting level. By a combination of electrophysiological, pharmacological, and immunohistochemical approaches, we show that salamander rods functionally express large-conductance Ca(2+)- and voltage-dependent potassium (BK) channel and intermediate-conductance Ca(2+)-dependent potassium (IK) channel, but not small-conductance Ca(2+)-dependent potassium channel (SK) subtypes. Application of 100 nM iberiotoxin and 100 nM clotrimazole reduced net I(KCa) to 36% and 63%, respectively, whereas the current was unaffected by application of 1 microM apamin. Consistently, anti- SK1, -SK2, and -SK3 antibodies were unable to stain rod photoreceptors, whereas both anti-BK and -SK4/ IK1 antibodies heavily stained the ellipsoid region of the inner segments of the rods. Moreover, by using current-clamp experiments, it was clearly seen that the strong clamping effect of the total I(KCa) was lost when IbTx, but not CLTZ, was applied to the bath. This behavior strongly suggests that of BK and IK channels, only the former are responsible for the clamping effect on the photoreceptor membrane potential.
Peng, Yingyun; Zhang, Tao; Mu, Wanmeng; Miao, Ming; Jiang, Bo
2016-01-15
Bacillus methylotrophicus SK19.001 is a glutamate-independent strain that produces poly(γ-glutamic acid) (γ-PGA), a polymer of D- and L-glutamic acids that possesses applications in food, the environment, agriculture, etc. This study was undertaken to explore the synthetic pathway of intracellular L- and D-glutamic acid in SK19.001 by investigating the effects of tricarboxylic acid cycle intermediates and different amino acids as metabolic precursors on the production of γ-PGA and analyzing the activities of the enzymes involved in the synthesis of L- and D-glutamate. Tricarboxylic acid cycle intermediates and amino acids could participate in the synthesis of γ-PGA via independent pathways in SK19.001. L-Aspartate aminotransferase, L-glutaminase and L-glutamate synthase were the enzymatic sources of L-glutamate. Glutamate racemase was responsible for the formation of D-glutamate for the synthesis of γ-PGA, and the synthetase had stereoselectivity for glutamate substrate. The enzymatic sources of L-glutamate were investigated for the first time in the glutamate-independent γ-PGA-producing strain, and multiple enzymatic sources of L-glutamate were verified in SK19.001, which will benefit efforts to improve production of γ-PGA with metabolic engineering strategies. © 2015 Society of Chemical Industry.
Shabalina, Irina G.; Vyssokikh, Mikhail Yu.; Gibanova, Natalia; Csikasz, Robert I.; Edgar, Daniel; Hallden-Waldemarson, Anne; Rozhdestvenskaya, Zinaida; Bakeeva, Lora E.; Vays, Valeria B.; Pustovidko, Antonina V.; Skulachev, Maxim V.; Cannon, Barbara; Skulachev, Vladimir P.; Nedergaard, Jan
2017-01-01
MtDNA mutator mice exhibit marked features of premature aging. We find that these mice treated from age of ≈100 days with the mitochondria-targeted antioxidant SkQ1 showed a delayed appearance of traits of aging such as kyphosis, alopecia, lowering of body temperature, body weight loss, as well as ameliorated heart, kidney and liver pathologies. These effects of SkQ1 are suggested to be related to an alleviation of the effects of an enhanced reactive oxygen species (ROS) level in mtDNA mutator mice: the increased mitochondrial ROS released due to mitochondrial mutations probably interact with polyunsaturated fatty acids in cardiolipin, releasing malondialdehyde and 4-hydroxynonenal that form protein adducts and thus diminishes mitochondrial functions. SkQ1 counteracts this as it scavenges mitochondrial ROS. As the results, the normal mitochondrial ultrastructure is preserved in liver and heart; the phosphorylation capacity of skeletal muscle mitochondria as well as the thermogenic capacity of brown adipose tissue is also improved. The SkQ1-treated mice live significantly longer (335 versus 290 days). These data may be relevant in relation to treatment of mitochondrial diseases particularly and the process of aging in general. PMID:28209927
Hernández-Bernal, Francisco; Castellanos-Sierra, Georgina; Valenzuela-Silva, Carmen M; Catasús-Álvarez, Karem M; Martínez-Serrano, Osmany; Lazo-Diago, Odalys C; Bermúdez-Badell, Cimara H; Causa-García, José R; Domínguez-Suárez, Juan E
2015-06-21
To compare the efficacy and safety of recombinant streptokinase (rSK) vs hydrocortisone acetate-based suppositories in acute hemorrhoidal disease. A multicenter (11 sites), randomized (1:1:1), open, controlled trial with parallel groups was performed. All participating patients gave their written, informed consent. After inclusion, patients with acute symptoms of hemorrhoids were centrally randomized to receive, as outpatients, by the rectal route, suppositories of rSK 200000 IU of one unit every 8 h (first 3 units) and afterwards every 12 h until 8 administrations were completed (schedule A), one unit every 8 h until 6 units were completed (schedule B), or 25 mg hydrocortisone acetate once every 8 h up to a maximum of 24 administrations. Evaluations were performed at 3, 5, and 10 d post-inclusion. The main end-point was the 5(th)-day response (disappearance of pain and bleeding, and ≥ 70% reduction of the lesion size). Time to response and need for thrombectomy were secondary efficacy variables. Adverse events were also evaluated. Groups were homogeneous with regards to demographic and baseline characteristics. Fifth day complete response rates were 156/170 (91.8%; 95%CI: 87.3-96.2), 155/170 (91.2%; 95%CI: 86.6%-95.7%), and 46/170 (27.1%; 95%CI: 20.1%-34.0%) with rSK (schedule A and B) and hydrocortisone acetate suppositories, respectively. These 64.6% and 63.9% differences (95%CI: 56.7%-72.2% and 55.7%-72.0%) were highly significant (P < 0.001). This advantage was detected since the early 3(rd) day evaluation (68.8% and 64.1% vs 7.1% for the rSK and active control groups, respectively; P < 0.001) and was maintained even at the late 10(th) day assessment (97.1% and 93.5% vs 67.1% for rSK and hydrocortisone acetate, respectively; P < 0.001). Time to response was 3 d (95%CI: 2.9-3.1) for both rSK groups and 10 d (95%CI: 9.3-10.7) in the hydrocortisone acetate group. This difference was highly significant (P < 0.001). All subgroup stratified analyses (with or without thrombosis and hemorrhoid classification) showed a statistically significant advantage for the rSK groups. Thrombectomy was necessary in 4/251 and 14/133 patients with baseline thrombosis in the rSK and hydrocortisone acetate groups, respectively (P < 0.001). There were no adverse events attributable to the experimental treatment. rSK suppositories showed a significant advantage over a widely-used over-the-counter hydrocortisone acetate preparation for the treatment of acute hemorrhoidal illness, as well as having an adequate safety profile.
Hernández-Bernal, Francisco; Castellanos-Sierra, Georgina; Valenzuela-Silva, Carmen M; Catasús-Álvarez, Karem M; Martínez-Serrano, Osmany; Lazo-Diago, Odalys C; Bermúdez-Badell, Cimara H; Causa-García, José R; Domínguez-Suárez, Juan E; Investigators, Pedro A López-Saura; THERESA-4 (Treatment of HEmorrhoids with REcombinant Streptokinase Application) Group of
2015-01-01
AIM: To compare the efficacy and safety of recombinant streptokinase (rSK) vs hydrocortisone acetate-based suppositories in acute hemorrhoidal disease. METHODS: A multicenter (11 sites), randomized (1:1:1), open, controlled trial with parallel groups was performed. All participating patients gave their written, informed consent. After inclusion, patients with acute symptoms of hemorrhoids were centrally randomized to receive, as outpatients, by the rectal route, suppositories of rSK 200000 IU of one unit every 8 h (first 3 units) and afterwards every 12 h until 8 administrations were completed (schedule A), one unit every 8 h until 6 units were completed (schedule B), or 25 mg hydrocortisone acetate once every 8 h up to a maximum of 24 administrations. Evaluations were performed at 3, 5, and 10 d post-inclusion. The main end-point was the 5th-day response (disappearance of pain and bleeding, and ≥ 70% reduction of the lesion size). Time to response and need for thrombectomy were secondary efficacy variables. Adverse events were also evaluated. RESULTS: Groups were homogeneous with regards to demographic and baseline characteristics. Fifth day complete response rates were 156/170 (91.8%; 95%CI: 87.3-96.2), 155/170 (91.2%; 95%CI: 86.6%-95.7%), and 46/170 (27.1%; 95%CI: 20.1%-34.0%) with rSK (schedule A and B) and hydrocortisone acetate suppositories, respectively. These 64.6% and 63.9% differences (95%CI: 56.7%-72.2% and 55.7%-72.0%) were highly significant (P < 0.001). This advantage was detected since the early 3rd day evaluation (68.8% and 64.1% vs 7.1% for the rSK and active control groups, respectively; P < 0.001) and was maintained even at the late 10th day assessment (97.1% and 93.5% vs 67.1% for rSK and hydrocortisone acetate, respectively; P < 0.001). Time to response was 3 d (95%CI: 2.9-3.1) for both rSK groups and 10 d (95%CI: 9.3-10.7) in the hydrocortisone acetate group. This difference was highly significant (P < 0.001). All subgroup stratified analyses (with or without thrombosis and hemorrhoid classification) showed a statistically significant advantage for the rSK groups. Thrombectomy was necessary in 4/251 and 14/133 patients with baseline thrombosis in the rSK and hydrocortisone acetate groups, respectively (P < 0.001). There were no adverse events attributable to the experimental treatment. CONCLUSION: rSK suppositories showed a significant advantage over a widely-used over-the-counter hydrocortisone acetate preparation for the treatment of acute hemorrhoidal illness, as well as having an adequate safety profile. PMID:26109819
Dermoscopic Clues for Diagnosing Melanomas That Resemble Seborrheic Keratosis
Segura, Sonia; Aguilera, Paula; Scalvenzi, Massimiliano; Longo, Caterina; Barreiro, Alicia; Broganelli, Paolo; Cavicchini, Stefano; Llambrich, Alex; Zaballos, Pedro; Thomas, Luc; Malvehy, Josep; Puig, Susana; Zalaudek, Iris
2017-01-01
Importance Melanomas that clinically mimic seborrheic keratosis (SK) can delay diagnosis and adequate treatment. However, little is known about the value of dermoscopy in recognizing these difficult-to-diagnose melanomas. Objective To describe the dermoscopic features of SK-like melanomas to understand their clinical morphology. Design, Setting, and Participants This observational retrospective study used 134 clinical and dermoscopic images of histopathologically proven melanomas in 134 patients treated in 9 skin cancer centers in Spain, France, Italy, and Austria. Without knowledge that the definite diagnosis for all the lesions was melanoma, 2 dermoscopy-trained observers evaluated the clinical descriptions and 48 dermoscopic features (including all melanocytic and nonmelanocytic criteria) of all 134 images and classified each dermoscopically as SK or not SK. The total dermoscopy score and the 7-point checklist score were assessed. Images of the lesions and patient data were collected from July 15, 2013, through July 31, 2014. Main Outcomes and Measures Frequencies of specific morphologic patterns of (clinically and dermoscopically) SK-like melanomas, patient demographics, and interobserver agreement of criteria were evaluated. Results Of the 134 cases collected from 72 men and 61 women, all of whom were white and who had a mean (SD) age of 55.6 (17.5) years, 110 (82.1%) revealed dermoscopic features suggestive of melanoma, including pigment network (74 [55.2%]), blue-white veil (72 [53.7%]), globules and dots (68 [50.7%]), pseudopods or streaks (47 [35.1%]), and blue-black sign (43 [32.3%]). The remaining 24 cases (17.9%) were considered likely SKs, even by dermoscopy. Overall, lesions showed a scaly and hyperkeratotic surface (45 [33.6%]), yellowish keratin (42 [31.3%]), comedo-like openings (41 [30.5%]), and milia-like cysts (30 [22.4%]). The entire sample achieved a mean (SD) total dermoscopy score of 4.7 (1.6) and a 7-point checklist score of 4.4 (2.3), while dermoscopically SK-like melanomas achieved a total dermoscopy score of only 4.2 (1.3) and a 7-point checklist score of 2.0 (1.9), both in the range of benignity. The most helpful criteria in correctly diagnosing SK-like melanomas were the presence of blue-white veil, pseudopods or streaks, and pigment network. Multivariate analysis found only the blue-black sign to be significantly associated with a correct diagnosis, while hyperkeratosis and fissures and ridges were independent risk markers of dermoscopically SK-like melanomas. Conclusions and Relevance Seborrheic keratosis–like melanomas can be dermoscopically challenging, but the presence of the blue-black sign, pigment network, pseudopods or streaks, and/or blue-white veil, despite the presence of other SK features, allows the correct diagnosis of most of the difficult melanoma cases. PMID:28355453
Podeszwa, B; Niedbala, H; Polanski, J; Musiol, R; Tabak, D; Finster, J; Serafin, K; Milczarek, M; Wietrzyk, J; Boryczka, S; Mol, W; Jampilek, J; Dohnal, J; Kalinowski, D S; Richardson, D R
2007-11-15
The structure-activity relationships of new quinoline based compounds were investigated. Quinoline-5,8-dione and styrylquinoline scaffolds were used for the design of potentially active compounds. The novel analogues had comparable antiproliferative activity to cisplatin when evaluated in a bioassay against the P388 leukemia cell line. However, these compounds appeared far less efficient against SK-N-MC neuroepithelioma cells. Analogues without the 5,8-dione structure but containing the 8-carboxylic acid group were also found to induce antiproliferative activity. Hydrophobicity as measured by HPLC did not correlate with antiproliferative activity.
NASA Astrophysics Data System (ADS)
Peng, Cheng; Zou, Changchun; Pan, Li; Niu, Yixiong
2017-08-01
The Chinese Continental Scientific Drilling Project of the Cretaceous Songliao Basin (CCSD-SK) provides an excellent opportunity to understand the response of terrestrial environments to greenhouse climate change in the Cretaceous. We conducted a palaeoenvironmental study of the Late Cretaceous Qingshankou Formation (K2qn) based on geochemical log data from the SK-2 east borehole. According to the characteristic of Ti mainly from terrigenous minerals, the content of authigenic elements was calculated. Correlation space was proposed to study the variation of the correlation between two log curves along the depth. Palaeoenvironmental proxies were selected from log data to study the evolution of the climate and lake, productivity of the paleolake, and organic matter deposition. The results demonstrate that the productivity of the paleolake was driven by chemical weathering in K2qn, in which the first section of the Qingshankou Formation (K2qn1) has higher productivity than the second and third sections of the Qingshankou Formation (K2qn2+3). The high content of pyrite in several thin layers reveals lake water of high sulfate concentration. This may have been caused by acid rain related to large volcanic activity. In K2qn2+3, several periods of high productivity without the formation of source rocks and high organic matter content were identified. This may show that organic matter deposition was limited by low accommodation space or oxidation environment. Therefore, the preservation condition is suggested as the main controlling factor of organic matter deposition in K2qn.
Regulation of Episodic Growth Hormone Secretion by the Central Epinephrine System
Terry, L. Cass; Crowley, W. R.; Johnson, M. D.
1982-01-01
Catecholamines are postulated to regulate growth hormone (GH) secretion by their influence on the release of two hypothalamic substances, somatostatin, which inhibits GH release, and GH-releasing factor, as yet unidentified. Extensive pharmacologic studies in man and animals indicate a stimulatory effect of central norepinephrine and dopamine on GH, but the function of epiphephrine (EPI) is uncertain. Furthermore, many of the agents used to study the role of catecholamines in GH regulation are not selective in that they affect adrenergic as well as nor-adrenergic and/or dopaminergic neurotransmission. In the present investigation, central nervous system (CNS) EPI biosynthesis was selectively interrupted with the specific norepinephrine N-methyltransferase inhibitors, SK & F 64139 (Smith, Kline & French Laboratories) and LY 78335, (Eli Lilly & Co. Research Laboratories) and the effects of central EPI depletion on episodic GH secretion in the chronically cannulated rat model were determined. Inhibition of CNS EPI synthesis with SK & F 64139 caused complete suppression of episodic GH secretion and concomitantly reduced the EPI level in the hypothalamus without affecting dopamine or norepinephrine. Administration of LY 78335 produced similar effects on pulsatile GH. Morphine-induced, but not clonidine-induced, GH release also was blocked by SK & F 64139. These results indicate that (a) the central EPI system has a major stimulatory function in episodic GH release, (b) morphine-induced GH release is mediated by the central EPI system, and (c) clonidine stimulates GH release by activation of postsynaptic α-adrenergic receptors. Drugs that affect CNS adrenergic systems have a potential role in the diagnosis and treatment of disorders of GH secretion. PMID:7054231
Two-proton capture on the 68Se nucleus with a new self-consistent cluster model
NASA Astrophysics Data System (ADS)
Hove, D.; Garrido, E.; Jensen, A. S.; Sarriguren, P.; Fynbo, H. O. U.; Fedorov, D. V.; Zinner, N. T.
2018-07-01
We investigate the two-proton capture reaction of the prominent rapid proton capture waiting point nucleus, 68Se, that produces the borromean nucleus 70Kr (68Se + p + p). We apply a recently formulated general model where the core nucleus, 68Se, is treated in the mean-field approximation and the three-body problem of the two valence protons and the core is solved exactly. We compare using two popular Skyrme interactions, SLy4 and SkM*. We calculate E2 electromagnetic two-proton dissociation and capture cross sections, and derive the temperature dependent capture rates. We vary the unknown 2+ resonance energy without changing any of the structures computed self-consistently for both core and valence particles. We find rates increasing quickly with temperature below 2-4 GK after which we find rates varying by about a factor of two independent of 2+ resonance energy. The capture mechanism is sequential through the f5/2 proton-core resonance, but the continuum background contributes significantly.