On the formation of alkyl (aryl) chlorosilanes in the direct interaction of alkyl(aryl) chlorides with silicon Communication 6. Role of cuprous chloride in the formation of dialkyldichlorosilanes

1966 ◽  
Vol 15 (6) ◽  
pp. 965-971 ◽  
Author(s):  
S. A. Golubtsov ◽  
V. V. Korobov ◽  
K. K. Popkov ◽  
I. V. Trofimova ◽  
R. A. Turetskaya ◽  
...  
Keyword(s):  
Direct Interaction ◽  
Cuprous Chloride ◽  
Alkyl Aryl ◽  
Aryl Chlorides

Metal-Metal Cooperative Bond Activation by Heterobimetallic Alkyl, Aryl, and Acetylide PtII/CuI Complexes

2020 ◽  
Author(s):  
Shubham Deolka ◽  
Orestes Rivada Wheelaghan ◽  
Sandra Aristizábal ◽  
Robert Fayzullin ◽  
Shrinwantu Pal ◽  
...  
Keyword(s):  
Alkyl Group ◽  
Bond Activation ◽  
Bond Cleavage ◽  
Terminal Alkyne ◽  
Alkyl Aryl ◽  
Metal Metal ◽  
The Stability ◽  
Selective Formation ◽  
Organoplatinum Compounds

We report selective formation of heterobimetallic PtII/CuI complexes that demonstrate how facile bond activation processes can be achieved by altering reactivity of common organoplatinum compounds through their interaction with another metal center. The interaction of the Cu center with Pt center and with a Pt-bound alkyl group increases the stability of PtMe2 towards undesired rollover cyclometalation. The presence of the CuI center also enables facile transmetalation from electron-deficient tetraarylborate [B(ArF)4]- anion and mild C-H bond cleavage of a terminal alkyne, which was not observed in the absence of an electrophilic Cu center. The DFT study indicates that the role of Cu center acts as a binding site for alkyne substrate, while activating its terminal C-H bond.

scholarly journals Positive Regulation of fur Gene Expression via Direct Interaction of Fur in a Pathogenic Bacterium, Vibrio vulnificus

2007 ◽  
Vol 189 (7) ◽  
pp. 2629-2636 ◽  
Author(s):  
Hyun-Jung Lee ◽  
So Hyun Bang ◽  
Kyu-Ho Lee ◽  
Soon-Jung Park
Keyword(s):  
Gene Expression ◽  
Pathogenic Bacteria ◽  
Vibrio Vulnificus ◽  
Iron Concentration ◽  
Direct Interaction ◽  
Repeated Sequence ◽  
Upstream Region ◽  
Fur Protein

ABSTRACT In pathogenic bacteria, the ability to acquire iron, which is mainly regulated by the ferric uptake regulator (Fur), is essential to maintain growth as well as its virulence. In Vibrio vulnificus, a human pathogen causing gastroenteritis and septicemia, fur gene expression is positively regulated by Fur when the iron concentration is limited (H.-J. Lee et al., J. Bacteriol. 185:5891-5896, 2003). Footprinting analysis revealed that an upstream region of the fur gene was protected by the Fur protein from DNase I under iron-depleted conditions. The protected region, from −142 to −106 relative to the transcription start site of the fur gene, contains distinct AT-rich repeats. Mutagenesis of this repeated sequence resulted in abolishment of binding by Fur. To confirm the role of this cis-acting element in Fur-mediated control of its own gene in vivo, fur expression was monitored in V. vulnificus strains using a transcriptional fusion containing the mutagenized Fur-binding site (fur mt::luxAB). Expression of fur mt::luxAB showed that it was not regulated by Fur and was not influenced by iron concentration. Therefore, this study demonstrates that V. vulnificus Fur acts as a positive regulator under iron-limited conditions by direct interaction with the fur upstream region.

Approaching the 21st Century: Perspectives on Korean Industrial Relations

1997 ◽  
Vol 8 (1) ◽  
pp. 22-43 ◽  
Author(s):  
Seoghun Woo
Keyword(s):  
Trade Unions ◽  
Presidential Address ◽  
Industrial Relations ◽  
Direct Interaction ◽  
The Past ◽  
The Government ◽  
Time Changes ◽  
Future Direction ◽  
Major Factors

This paper argues that the future direction for the development of Korean industrial relations will evolve through direct interaction between employers and trade unions (either conflictual or cooperative). The government is likely to play a less interventionist role in industrial relations, compared with the past, and to adopt the role of mediator between unions and employers. Characteristics of Korean industrial relations during the pre- 1987 period is firstly examined; four major factors are used to explain the industrial relations practice during this time. Changes after 1987 are also considered. Special consideration is given to interaction between the environment and the three major industrial relations participants, and the interactions between them. Both macro and micro aspects of industrial relations are examined. The special Presidential Address (26/04/1996), known as New Conception of Industrial Relations, is also analysed in terms of its implications for future industrial relations issues in Korea.

scholarly journals Oxidized LDL but not angiotensin II induces the interaction between LOX-1 and AT1 receptors

2020 ◽  
Author(s):  
Li Lin ◽  
Ning Zhou ◽  
Le Kang ◽  
Qi Wang ◽  
Jian Wu ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Oxidized Ldl ◽  
Low Density Lipoprotein ◽  
Ldl Receptor ◽  
Density Lipoprotein ◽  
Direct Interaction ◽  
Cardiomyocyte Hypertrophy ◽  
Oxidized Low Density Lipoprotein ◽  
Protein Activation

Oxidized low-density lipoprotein (Ox-LDL) can induce cardiac hypertrophy, but the mechanism is still unclear. Here we elucidate the role of angiotensin II (AngII) receptor (AT1-R) in Ox-LDL-induced cardiomycyte hypertrophy. Inhibition of Ox-LDL receptor LOX-1 and AT1-R rather than AngII abolished Ox-LDL-induced hypertrophic responses. Similar results were obtained from the heart of mice lacking endogenous Ang II and their cardiomyocytes. Ox-LDL but not AngII induced binding of LOX-1 to AT1-R, and the inhibition of LOX-1 or AT1-R rather than AngII abolished the association of these two receptors. Ox-LDL-induced ERKs phosphorylation in LOX-1 and AT1-R-overexpression cells and the binding of both receptors were suppressed by the mutants of LOX-1 (Lys266Ala/Lys267Ala) or AT1-R (Glu257Ala), however, the AT1-R mutant lacking Gq protein-coupling ability only abolished the ERKs phosphorylation. The phosphorylation of ERKs induced by Ox-LDL in LOX-1 and AT1-R-overexpression cells was abrogated by Gq protein inhibitor but not by Jak2, Rac1 and RhoA inhibitors. Therefore, the direct interaction between LOX-1 and AT1-R and the downstream Gq protein activation are important mechanisms for Ox-LDL- but not AngII-induced cardiomyocyte hypertrophy

The Role of Parents in Children's Psychological Development

PEDIATRICS ◽  
1999 ◽  
Vol 104 (Supplement_1) ◽  
pp. 164-167 ◽  
Author(s):  
Jerome Kagan
Keyword(s):  
Direct Interaction ◽  
Psychological Development ◽  
Family Stories ◽  
Empiric Data ◽  
Role Of Parents

This article reviews the three major ways parents influence children: direct interaction, identification, and transmission of family stories. This essay summarizes some of the relevant empiric data in support of this claim and describes the operation of other mechanisms that also contribute to the child's development.

scholarly journals The Role of Macrophages in Vascular Repair and Regeneration after Ischemic Injury

2020 ◽  
Vol 21 (17) ◽  
pp. 6328
Author(s):  
Huiling Hong ◽  
Xiao Yu Tian
Keyword(s):  
Tissue Injury ◽  
Direct Interaction ◽  
Cell Types ◽  
Short Review ◽  
Potential Interaction ◽  
Hindlimb Ischemia ◽  
Vascular Repair ◽  
Injury Repair ◽  
Vascular Beds

Macrophage is one of the important players in immune response which perform many different functions during tissue injury, repair, and regeneration. Studies using animal models of cardiovascular diseases have provided a clear picture describing the effect of macrophages and their phenotype during injury and regeneration of various vascular beds. Many data have been generated to demonstrate that macrophages secrete many important factors including cytokines and growth factors to regulate angiogenesis and arteriogenesis, acting directly or indirectly on the vascular cells. Different subsets of macrophages may participate at different stages of vascular repair. Recent findings also suggest a direct interaction between macrophages and other cell types during the generation and repair of vasculature. In this short review, we focused our discussion on how macrophages adapt to the surrounding microenvironment and their potential interaction with other cells, in the context of vascular repair supported by evidences mostly from studies using hindlimb ischemia as a model for studying post-ischemic vascular repair.

Molecular site for nucleotide binding on an ATP-sensitive renal K+ channel (ROMK2)

1996 ◽  
Vol 271 (2) ◽  
pp. F275-F285 ◽  
Author(s):  
C. M. McNicholas ◽  
Y. Yang ◽  
G. Giebisch ◽  
S. C. Hebert
Keyword(s):  
Channel Gating ◽  
Direct Interaction ◽  
K Channel ◽  
Amino Terminus ◽  
Atp Binding Site ◽  
Gating Mechanism ◽  
Alternatively Spliced ◽  
Carboxy Terminal ◽  
Apical Membranes

ATP-sensitive, inwardly rectifying K+ channels are present in apical membranes of the distal nephron and play a major role in K+ recycling and secretion. The cloned renal K+ channel, ROMK1, is a candidate for the renal epithelial K+ channel, since it shares many functional characteristics with the native channel. Additionally, ROMK1 contains a putative carboxy-terminal ATP-binding site. Although ROMK1 channel activity could be reactivated by cytosolic Mg-ATP after rundown, the role of nucleotides in channel gating was less certain. We now show that an alternatively spliced transcript of the ROMK channel gene, ROMK2, which encodes a K+ channel with a truncated amino terminus, expresses an ATP-regulated and ATP-sensitive K+ channel (IKATP). Differences in the amino terminus of ROMK isoforms alters the sensitivity of the channel-gating mechanism to ATP. To test whether ATP sensitivity of renal IKATP is mediated by direct interaction of nucleotide, point mutation of specific residues within the ROMK2 phosphate loop (P-loop) were investigated. These either enhanced or attenuated the sensitivity to both activation and inhibition by Mg-ATP, thus demonstrating a direct interaction of nucleotide with the channel-forming polypeptide.

scholarly journals Differential regulation of Ca2+ influx by ORAI channels mediates enamel mineralization

2019 ◽  
Vol 12 (578) ◽  
pp. eaav4663 ◽  
Author(s):  
Miriam Eckstein ◽  
Martin Vaeth ◽  
Francisco J. Aulestia ◽  
Veronica Costiniti ◽  
Serena N. Kassam ◽  
...  
Keyword(s):  
Consumption Rate ◽  
Redox Homeostasis ◽  
Direct Interaction ◽  
Redox Status ◽  
Cellular Functions ◽  
Enamel Defects ◽  
Targeted Deletion ◽  
Anhidrotic Ectodermal Dysplasia ◽  
Enamel Mineralization

Store-operated Ca2+ entry (SOCE) channels are highly selective Ca2+ channels activated by the endoplasmic reticulum (ER) sensors STIM1 and STIM2. Their direct interaction with the pore-forming plasma membrane ORAI proteins (ORAI1, ORAI2, and ORAI3) leads to sustained Ca2+ fluxes that are critical for many cellular functions. Mutations in the human ORAI1 gene result in immunodeficiency, anhidrotic ectodermal dysplasia, and enamel defects. In our investigation of the role of ORAI proteins in enamel, we identified enamel defects in a patient with an ORAI1 null mutation. Targeted deletion of the Orai1 gene in mice showed enamel defects and reduced SOCE in isolated enamel cells. However, Orai2−/− mice showed normal enamel despite having increased SOCE in the enamel cells. Knockdown experiments in the enamel cell line LS8 suggested that ORAI2 and ORAI3 modulated ORAI1 function, with ORAI1 and ORAI2 being the main contributors to SOCE. ORAI1-deficient LS8 cells showed altered mitochondrial respiration with increased oxygen consumption rate and ATP, which was associated with altered redox status and enhanced ER Ca2+ uptake, likely due to S-glutathionylation of SERCA pumps. Our findings demonstrate an important role of ORAI1 in Ca2+ influx in enamel cells and establish a link between SOCE, mitochondrial function, and redox homeostasis.

scholarly journals Cathepsins in Bacteria-Macrophage Interaction: Defenders or Victims of Circumstance?

2020 ◽  
Vol 10 ◽  
Author(s):  
Lidia Szulc-Dąbrowska ◽  
Magdalena Bossowska-Nowicka ◽  
Justyna Struzik ◽  
Felix N. Toka
Keyword(s):  
Proteolytic Enzymes ◽  
Bacterial Species ◽  
Animal Health ◽  
Adaptive Immune Response ◽  
Direct Interaction ◽  
Adaptive Immune ◽  
Intracellular Digestion ◽  
Close Relationship ◽  
Recent Developments

Macrophages are the first encounters of invading bacteria and are responsible for engulfing and digesting pathogens through phagocytosis leading to initiation of the innate inflammatory response. Intracellular digestion occurs through a close relationship between phagocytic/endocytic and lysosomal pathways, in which proteolytic enzymes, such as cathepsins, are involved. The presence of cathepsins in the endo-lysosomal compartment permits direct interaction with and killing of bacteria, and may contribute to processing of bacterial antigens for presentation, an event necessary for the induction of antibacterial adaptive immune response. Therefore, it is not surprising that bacteria can control the expression and proteolytic activity of cathepsins, including their inhibitors – cystatins, to favor their own intracellular survival in macrophages. In this review, we summarize recent developments in defining the role of cathepsins in bacteria-macrophage interaction and describe important strategies engaged by bacteria to manipulate cathepsin expression and activity in macrophages. Particularly, we focus on specific bacterial species due to their clinical relevance to humans and animal health, i.e., Mycobacterium, Mycoplasma, Staphylococcus, Streptococcus, Salmonella, Shigella, Francisella, Chlamydia, Listeria, Brucella, Helicobacter, Neisseria, and other genera.

scholarly journals Intestinal Microbiota: A Novel Target to Improve Anti-Tumor Treatment?

2019 ◽  
Vol 20 (18) ◽  
pp. 4584 ◽  
Author(s):  
Romain Villéger ◽  
Amélie Lopès ◽  
Guillaume Carrier ◽  
Julie Veziant ◽  
Elisabeth Billard ◽  
...  
Keyword(s):  
Side Effects ◽  
Gut Microbiota ◽  
Host Response ◽  
Fecal Microbiota Transplantation ◽  
Direct Interaction ◽  
Fecal Microbiota ◽  
Intestinal Microbiome ◽  
Wide Range ◽  
Novel Target

Recently, preclinical and clinical studies targeting several types of cancer strongly supported the key role of the gut microbiota in the modulation of host response to anti-tumoral therapies such as chemotherapy, immunotherapy, radiotherapy and even surgery. Intestinal microbiome has been shown to participate in the resistance to a wide range of anticancer treatments by direct interaction with the treatment or by indirectly stimulating host response through immunomodulation. Interestingly, these effects were described on colorectal cancer but also in other types of malignancies. In addition to their role in therapy efficacy, gut microbiota could also impact side effects induced by anticancer treatments. In the first part of this review, we summarized the role of the gut microbiome on the efficacy and side effects of various anticancer treatments and underlying mechanisms. In the second part, we described the new microbiota-targeting strategies, such as probiotics and prebiotics, antibiotics, fecal microbiota transplantation and physical activity, which could be effective adjuvant therapies developed in order to improve anticancer therapeutic efficiency.

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