A new analytical material-enhanced laser desorption ionization (MELDI) based approach for the determination of low-mass serum constituents using fullerene derivatives for selective enrichment

60]fullerene derivatives (dioctadecyl methano[60]fullerene, [60]fullerenoacetic acid, and IDA-[60]fullerene) were prepared and subjected to a comprehensive characterization study including protein binding properties and capacity. These fullerene derivatives were successfully applied as material-enhanced laser desorption/ionization (MELDI) carrier materials. It is shown that diverse functionalities result in characteristic human serum peak patterns (m/z 2000-20 000) in terms of signal intensity as well as the number of detectable masses. In addition, the fullerene derivatives clearly provided differences in the low molecular weight mass region (m/z 1000-4000) after elution of the adsorbed serum constituents, and [60]fullerenoacetic acid was the most effective carrier material. Novel high-speed, monolithic, high-resolution capillary columns, prepared by thermally initiated copolymerization of methylstyrene (MSt) and 1,2-bis(p-vinylphenyl)ethane (BVPE) were employed for eluate separation and target spotting. Thus, serum compounds in the low-mass range were successfully fractionated and subjected to MALDI-MS/MS analysis. This contribution, hence, proposes a new "top-down" strategy for proteome research enabling protein profiling as well as biomarker identification in the low-mass range using selective enrichment, high-resolution separation, and offline MALDI-MS/MS evaluation.     

Impact of nano-zinc-oxide as an alternative source of zinc in date palm culture media

Plant Cell, Tissue and Organ Culture (PCTOC) - Leaf chlorosis is often a problem in micropropagated Rubus idaeus, which makes successful acclimatization difficult. We found that...     

Essential metals,vitamins and antioxidant enzyme activities in COVID-19 patients and their potential associations with the disease severity

BioMetals - The role of micronutrient deficiency in the pathogenesis of COVID-19 has been reviewed in the literature; however, the data are limited and conflicting. This study investigated the...     

Accuracy and reproducibility of voxel based superimposition of cone beam computed tomography models on the anterior cranial base and the zygomatic arches

Superimposition of serial Cone Beam Computed Tomography (CBCT) scans has become a valuable tool for three dimensional (3D) assessment of treatment effects and stability. Voxel based image registration is a newly developed semi-automated technique for superimposition and comparison of two CBCT scans. The accuracy and reproducibility of CBCT superimposition on the anterior cranial base or the zygomatic arches using voxel based image registration was tested in this study. 16 pairs of 3D CBCT models were constructed from pre and post treatment CBCT scans of 16 adult dysgnathic patients. Each pair was registered on the anterior cranial base three times and on the left zygomatic arch twice. Following each superimposition, the mean absolute distances between the 2 models were calculated at 4 regions: anterior cranial base, forehead, left and right zygomatic arches. The mean distances between the models ranged from 0.2 to 0.37 mm (SD 0.08-0.16) for the anterior cranial base registration and from 0.2 to 0.45 mm (SD 0.09-0.27) for the zygomatic arch registration. The mean differences between the two registration zones ranged between 0.12 to 0.19 mm at the 4 regions. Voxel based image registration on both zones could be considered as an accurate and a reproducible method for CBCT superimposition. The left zygomatic arch could be used as a stable structure for the superimposition of smaller field of view CBCT scans where the anterior cranial base is not visible.     

Platelet derived growth factor regulates ABCA1 expression in vascular smooth muscle cells

The ATP-binding cassette transporter A1 (ABCA1) regulates lipid efflux from peripheral cells to High-density lipoprotein. The platelet-derived growth factor (PDGF) is a potent mitogen that enables vascular smooth muscle cells to participate in atherosclerosis. In this report, we showed that PDGF suppressed endogenous expression of ABCA1 in cultured vascular smooth muscle cells. Exposure of CRL-208 cells to PDGF elicited a rapid phosphorylation of a kinase downstream from PI3-K, Akt. The constitutively active form of both p110, a subunit of PI3-K, and Akt inhibited activity of the ABCA1 promoter. In conclusion, PI3-K-Akt pathways participate in PDGF-suppression of ABCA1 expression.     

Hypertonicity increases sodium transporters in cortical collecting duct cells independently of PGE2

Cyclooxygenase-2 (COX-2) expression is increased by hypertonicity. Therefore we hypothesized that hypertonicity increased PGE(2) can modulate the sodium transporters (Na(+)/K(+)-ATPase: NKA, epithelial sodium channel: ENaC, and sodium hydrogen exchanger: NHE) in M1 cortical collecting duct (CCD) cells. We demonstrated by immunoblotting a 2-fold increase in NKA expression and activity following hypertonic treatment. α-ENaC was also increased, however sgk1, an ENaC activator, decreased in response to hypertonicity. Other CCD sodium transporters (β-ENaC, NHE) were unchanged. Hypertonicity also increased PGE(2) but EP(4) receptor mRNA was unaltered. PGE(2) increased intracellular Na(+) and cAMP production in M1 cells, but PGE(2)-stimulated cAMP response was attenuated by hypertonicity. Overall, PGE(2) had no effect on sodium transporter levels. Since neither COX inhibition nor EP(4) siRNA altered the induction of NKA, we propose that sodium transporter regulation by hypertonicity is independent of PGE(2). Altogether, these data indicate that despite a concomitant increase in PGE(2) production and sodium transporter expression in hypertonicity, both pathways are acting independently of each other.     

Involvement of an NKG2D ligand H60c in epidermal dendritic T cell-mediated wound repair

Dendritic epidermal T cells (DETCs) found in mouse skin are NKG2D-positive γδ T cells involved in immune surveillance and wound repair. It is assumed that the interaction of an NKG2D receptor on DETCs and an MHC class I-like NKG2D ligand on keratinocytes activates DETCs, which then secrete cytokines promoting wound repair. However, direct evidence that DETC activation through NKG2D signaling promotes wound repair is not available. In the present study, we generated mAbs for an NKG2D ligand H60c previously suggested to be expressed specifically on skin keratinocytes. Local administration of H60c-specific mAb inhibited activation of DETCs and significantly delayed wound repair. Likewise, administration of NKG2D-specific mAb impaired wound repair to a similar extent. The delay in wound closure resulting from the blockade of the NKG2D pathway was comparable to that observed in γδ T cell-deficient mice. These results indicate that H60c/NKG2D interactions play a critical role in wound repair. Reassessment of binding affinities showed that H60c monomers bind to NKG2D with affinity (K(d) = 26 ± 3.2 nM) comparable to those of other high-affinity NKG2D ligands. H60c is transcribed not only in skin but also in tissues such as tongue and female reproductive tract known to contain epithelium-resident γδ T cells expressing invariant TCRs, suggesting a more general role for H60c in the maintenance of epithelial integrity.