Pressure-Sensitive Adhesives Based on Epoxidized Soybean Oil and Dicarboxylic Acids

Existing pressure sensitive adhesives (PSAs) are mainly derived from petrochemicals. This study describes a novel approach for development of biobased PSAs. Epoxidized soybean oil was polymerized and cross-linked with a dicarboxylic acid to generate superior PSAs. The dicarboxylic acids used in this study included dimer acid (DA), sebacic acid, adipic acid, and a difunctional polymeric carboxylic acid that was prepared from polymerization of bisphenol A diglycidyl ether (BPAGE) and an excess of DA. AMC-2, a chromium­(III)-based organometallic compound, was found to be the most effective catalyst for the polymerization/cross-linking. The PSAs had a peel strength of 1.4–5.0 N/cm, a loop tack of 7.1–12.6 N, a shear strength of 34 min to more than 168 h, and a good aging resistance. The adhesive properties of the PSAs can be tailored for specific applications such as PSA tapes and labels through the selection of the dicarboxylic acid and its usage. Incorporation of a small amount of phenylene-containing monomer BPAGE into the PSAs significantly increases the peel and shear strengths of the resulting PSAs. This new class of PSAs can be fully based on renewable materials. The preparation of the PSAs does not use any organic solvent or toxic chemicals, thus being environmentally friendly

Expression of WT and homomeric mutant channels in patch clamp recordings.

<p>(A) representative currents recorded by inside-out excised patch-clamp technique from COSm6 cells expressing WT channels and various mutant channels, at +50 mV pipette potential. Patches were exposed to different concentrations of Mg-free ATP as indicated. Dashed line indicates zero current (WT and homS225T channels) or zero channel level (homDel and homT, del channels). (B) Western Blot of Flag-tagged SUR1 (fSUR1) from various constructs are indicated. The mature (cell surface) complex-glycosylated bands and immature core-glycosylated bands are indicated as upper bands (white arrow) and lower bands (black arrow) respectively. NT = not transfected.</p

Increased basal K_ATP activity in both hetDel and hetT, del channels.

<p>⁸⁶Rb⁺ efflux of mutant Kir6.2 subunits coexpressed with WT subunits in 1∶1 DNA ratio, under metabolic inhibition (A) and in basal states (B). Data points indicate means ± SEM of n = 5. * indicates P<0.05 compared with WT by One-Way ANOVA analysis. NT  =  not transfected (no statistic given).</p

Decreased ATP sensitivity in both hetDel and hetT, del channels.

<p>(A) Representative currents recorded by inside-out excised patch-clamp technique from COSm6 cells expressing WT channels and hetT, del mutants. Patches were exposed to different concentrations of Mg-free ATP as indicated. (B) ATP dose-response relationships, fit by Hill equation as described in methods. Data points indicate means ± SEM of n = 5–7 patches. * indicates P<0.05 compared with WT by One-Way ANOVA analysis. The fitted K_1/2 for WT, homS225T, hetS225T, hetDel, and hetT, del channels are 13.75, 25.06, 14.8, 22.87 and 43.94 (in μM) and the Hill coefficients are 1.6, 1.3, 1.1, 1.28 and 1.2, respectively.</p

Heterozygous S225T, deletion channels display higher channel open probability, assessed by the ‘PIP₂’ method.

<p>(A) Representative currents recorded by inside-out excised patch-clamp technique from COSm6 cells expressing WT channels and hetT, del mutants. Patches were exposed to different concentrations of Mg-free ATP and PIP₂ as indicated. (B) Mean estimated Po for various channels: WT (0.53±0.04); homS225T (0.62±0.04); hetS225T (0.59±0.03); hetDel (0.64±0.04); hetT, del (0.66+0.02). * indicates statistically significant difference compared with WT (Student's t-test, p-value <0.05). n = 6–12.</p

Homology modeling of Kir6.2 from Kir2.2 structure with PyMOL software.

<p>(A) S225T is colored in yellow and deleted amino acids 226–232 (-PEGEVVP-) are colored in orange. (B) E227 and E229 are colored and labeled in red while R192 and R314 are colored and labeled in blue. The structure model reveals the possible interaction between the deleted amino acid P232 (orange spheres) and V319 in the proposed Kir6.2 Ankyrin-B binding site (a.a. 316 to a.a. 323 –VPIVAEED- colored in magenta).</p

Decreased K_ATP activity in both homDel and homT, del channels.

<p>Representative ⁸⁶Rb⁺ efflux profile comparing untransfected COSm6 cells (Un) and cells transfected with WT, homS225T, homDel and homT, del channels in metabolic inhibition (A) and in basal conditions (B). Data points indicate means ± SEM of n = 4. NT  =  not transfected.</p

Elimination of <i>M</i>. <i>smegmatis</i> from macrophages by low concentrations of DDP alone or combined with first-line anti-tuberculosis drugs.

(A) The effect of DDP on cell proliferation by the trypan blue exclusion assay. The doses of DDP were 0, 0.25, 0.5, 1, 2, 4, 8 and 10 μg/mL. (B) The effect of DDP on cell viability by CCK-8 (cell counting kit-8) detection. (C) CFU of intracellular M. smegmatis after treatment with different concentrations of DDP. Macrophage cell lines J774A.1, RAW264.7, and THP-1 were infected with M. smegmatis at an MOI of 0.1 for 1 hour, and then the cells were treated with DDP for 24 hours. The doses of DDP were 0, 2, 4, and 6 μg/mL. (D) CFU of intracellular M. smegmatis after DDP treatment for different times. Macrophages were infected with M. smegmatis at an MOI of 0.1 for 1 hour, and then cells were treated with 1 μg/mL DDP or PBS for 1 day and 3 days, respectively. (E) CFU of intracellular M. smegmatis after DDP treatment alone or combined with isoniazid (INH) or rifampicin (RIF). RAW264.7 cells were infected with M. smegmatis at an MOI of 0.1 for 1 hour and then treated with DDP or INH, RIF, DDP combined with INH, or DDP combined with RIF for 24 hours. The concentrations of DDP, INH and RIF were 1μg/mL, 5 μM and 10 μM, respectively. The experiment for each group was carried out in triplicate. * p p p p M. smegmatis; DDP: Cisplatin.</p

The mechanisms of DDP at low concentration elimination intracellular Mycobacterium.

Low concentration of DDP activates JAK, p38 MAPK and PI3K pathways in the infected macrophages, promotes the phosphorylation of p53 protein, and then the expression of apoptosis related protein Bax increased and Bcl-2 decreased, leading to the cell apoptosis, thus eliminating intracellular mycobacteria and reducing the spread of mycobacteria. MS:M.smegmatis; DDP:Cisplatin.</p

Low concentration of DDP promotes p53 phosphorylation to eliminate <i>M</i>. <i>smegmatis</i> in macrophages.

(A) Western-blot detection the expression of phosphorylated p53 after 1 μg/mL DDP treatment for different time. (B) Western-blot detection phosphorylated p53 expression 48 h after DDP treatment at different concentration. (C) Bacteria count in macrophages after the treatment of DDP combined with p53 promoter or inhibitor. Raw264.7 cells infected with M.smegmatis were treated with 1 μg/mL DDP, or 1 μg/mL DDP combined with 10 μM p53 promoter (Kevetrin hydrochloride), or 1 μg/mL DDP combined with 10 μM p53 inhibitor (Pifithrin -α hydrobromide) for 24 h. (D) CFU in macrophages after Kevetrin hydrochloride treatment. Raw264.7 cells infected with M.smegmatis were treated with Kevetrin hydrochloride at the concentration of 10 μM, 15 μM, 20 μM for 24 h respectively. (E) CFU in macrophages after Kevetrin hydrochloride treatment alone or combined with RIF. **p p p M.smegmatis; DDP:Cisplatin.</p