HEK293 cells

When assayed in HEK293 cells transfected with the cloned human, rat and guinea pig TRPVl, (23a) showed similar potencies. Not unexpeetedly, (23a) showed poor metabolic stability and a structure-activity study to optimize potency and drug-like properties was initiated. Modification on the left-handed A -aryl section showed that ... 

An azetidine motif was also present in two series of CBi antagonist compounds disclosed by Vernalis Research [335, 336]. In the former, compound (560) was claimed to have an affinity of 285 nM in transfected HEK293 cells using tritium-labelled (382). Among the preferred indications were psychosis, schizophrenia, smoking cessation and eating disorders associated with excessive food intake. Compound (561) was claimed to have an affinity of 0.8 nM in the same binding assay [336]. 

Cui, D.X. et al. (2005) Effect of single wall carbon nanotubes on human HEK293 cells. Toxicology Letters, 155 (1), 73-85. 

A number of compounds activate TRPA1 without any apparent ability to form covalent adducts, including nonelectrophilic fenamate nonsteroidal anti-inflammatory drugs (NSAIDs), such as flufenamic acid (17, FFA), niflumic acid (18, NFA), and mefenamic acid (19, MFA) [13]. Phenols such as thymol (20) and 2-ferf-butyl-5-methylphenol (21) have been shown to activate human TRPA1 with micromolar EC50 values in stably transfected HEK293 cells [14]. 

Stereochemistry also plays an important role in the recently disclosed 3,4-dihydropyrimidinethione analogs [32]. Racemic dihydropyrimidine derivative (32) is reported to inhibit activation by the TRPA1 agonist HH-dibenzo[fc,e]azepine-10-carboxylic acid methyl ester (16) with an IC50 value of 128 nM for human TRPA1 in HEK293 cells. 

Recent results that examined the effect of pyrethroids on voltage-gated sodium channels expressed in human embryonic kidney (HEK293) cells grown in... 

He B, Soderlund DM (2010) Human embryonic kidney (HEK293) cells express endogenous voltage-gated sodium currents and Nav1.7 sodium channels. Neurosci Lett 469 268-272... 

Recently, it was shown that the thromboxane receptor itself is a substrate ofcGMP-PK and cAMP-PK in HEK293 cells, HEL cells, or with purified enzymes in vitro. Phosphorylation of its cytoplasmic carboxyterminal domain prevented the thromboxane receptor from coupling to and activating G-proteins [36, 37]. For intact platelets, TxA2 receptor phosphorylation has not yet been shown, however, it would provide another explanation for the inhibition of PLC activation and subsequent intracellular Ca2+ elevation and granule secretion in response to cyclic nucleotides. 

Fig. 2.162. Absorption spectra of Amphiopl expressed in HEK293s cells (a) and the HPLC patterns of retinal oximes (b). Absorption spectra and the HPLC patterns were measured before (a, curve 1, and b, top trace) and after irradiation at 520 nm for 2 min (a, curve 2, and b, middle trace). The HPLC pattern of retinal oximes extracted from a mixture of irradiated and non-irradiated bovine rhodopsin in equal amounts is indicated as a reference (b, bottom trace). The absorption maxima of the original pigment and its phoroproduct are shown in panel (a). Reprinted with permission from M. Koyanagi et al. [334].

Degeneration or neutrophil infiltration in vivo were exhibited around CNTs examined throughout the experimental period. Different sizes of CNTs cause different cell reaction (Goh et al., 2003). For example, SWCNTs inhibit HEK293 cell proliferation, decrease cell adhesive ability in a dose- and time-dependent manner (Grunlan et al., 2004) as shown in Fig. 9.7 and Fig. 9.8. 

Some reports showed that pure CNTs can cross cell membrane with high efficiency (Kam et al., 2005 Pantarotto et al., 2004). Some reports showed that CNTs could not be found in cells by HR-TEM (Carrero-Sanchez et al., 2006 Stone and Donaldson, 2006). In our previous studies, we also found that pure CNTs were very difficult to enter into cells such as human fibroblast cells (Tian et al., 2006) and HEK293 cells (Cui et al., 2005), and stem cells, we spent almost 6 months on sectioning these cells and looking for CNTs within cells by HR-TEM, finally we could not find CNTs within cells, we only observed that a lot of CNTs attached to the surface of cells (Fig. 9.10a), and some tubers appeared on the surface of CNTs (Fig. 9.10c). That is to say, non-modified CNTs enter into cells via low-efficient means. However, biomolecules-modified CNTs can efficiently enter into almost all... 

Fig. 9.8 Apoptosis of HEK293 cells induced by SWCNTs. Bl DNA electrophoresis of cells cultured with 25g/ml SWCNTs for 1-5 days, M molecular marker, no. 1-5 denote the results of cells cultured for day 1-5, respectively B2 DNA electrophoresis results of control cells cultured for day 1-5 C the cell cycle distribution of HEK293 cells cultured with 25 lg/ml SWCNTs for 4 days, the percentage of sub-Gl cells (apoptosis cells) was 43.5%. (Grunlan et al., 2000. With permission from Elsevier) (See Color Plates)...

Fig. 9.7 Indirect immunofluorescent staining of SWCNTs-treated HEK293 cells for day 1-5 by fluorescent microscopy (x 630). Green cadherin red collagen blue cellular nucleus staining with DAPI. The expression levels of cadherin and collagen IV in cells decreased gradually as the culture days increased HEK293 cells gradually detached from the cell populations as the culture days increased (Grunlan et al., 2004. With permission from Elsevier)...

O Farrell, C., et al., Transfected synphilin-1 forms cytoplasmic inclusions in HEK293 cells. Brain Res Mol Brain Res, 2001, 97/3/, 94-102. 

Recently, structure-activity relationship studies of human /3-defensin have investigated the structural characteristics necessary for chemoattractive activities. Importantly, the native structure of HBD-3 has three disulfide bonds between cysteine residues C1-C5, C2-C4, C3-C6 and in this configuration is able to induce migration of CCR6 HEK293 cells at concentrations as low as lOngmPf An investigation by Wu demonstrated that... 

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