Improved Reversion of Calcifications in Porcine Aortic Heart Valves Using Elastin-Targeted Nanoparticles.

Calcified aortic valve disease in its final stage leads to aortic valve stenosis, limiting cardiac function. To date, surgical intervention is the only option for treating calcific aortic valve stenosis. This study combined controlled drug delivery by nanoparticles (NPs) and active targeting by antibody conjugation. The chelating agent diethylenetriaminepentaacetic acid (DTPA) was covalently bound to human serum albumin (HSA)-based NP, and the NP surface was modified using conjugating antibodies (anti-elastin or isotype IgG control). Calcification was induced ex vivo in porcine aortic valves by preincubation in an osteogenic medium containing 2.5 mM sodium phosphate for five days. Valve calcifications mainly consisted of basic calcium phosphate crystals. Calcifications were effectively resolved by adding 1-5 mg DTPA/mL medium. Incubation with pure DTPA, however, was associated with a loss of cellular viability. Reversal of calcifications was also achieved with DTPA-coupled anti-elastin-targeted NPs containing 1 mg DTPA equivalent. The addition of these NPs to the conditioned media resulted in significant regression of the valve calcifications compared to that in the IgG-NP control without affecting cellular viability. These results represent a step further toward the development of targeted nanoparticular formulations to dissolve aortic valve calcifications.

Tofacitinib and Baricitinib Are Taken up by Different Uptake Mechanisms Determining the Efficacy of Both Drugs in RA.

BACKGROUND: Rheumatoid arthritis (RA) is a systemic autoimmune disease in which synovial fibroblasts (SF) play a key role. Baricitinib and Tofacitinib both act intracellularly, blocking the ATP-binding side of JAK proteins and thereby the downstream signalling pathway via STAT-3. Therefore, we investigated the role of organic cation transporters (OCTs) in Baricitinib and Tofacitinib cellular transport. METHODS: OCT expression was analysed in SF isolated from RA and osteoarthritis (OA) patients, as well as peripheral blood mononuclear cells. The interaction of Baricitinib and Tofacitinib with OCTs was investigated using quenching experiments. The intracellular accumulation of both drugs was quantified using LC/MS. Target inhibition for both drugs was tested using Western blot for phosphorylated JAK1 and STAT3 upon stimulation with IL-6. RESULTS: MATE-1 expression increased in OASF compared to RASF. The other OCTs were not differentially expressed. The transport of Baricitinib was not OCT dependent. Tofacitinib; however, was exported from RASF in a MATE-1 dependent way. Tofacitinib and Baricitinib showed comparable inhibition of downstream signalling pathways. CONCLUSION: We observed different cellular uptake strategies for Baricitinib and Tofacitinib. Tofacitinib was exported out of healthy cells due to the increased expression of MATE1. This might make Tofacitinib the favourable drug.

In vivo corrosion and damages in modular shoulder prostheses.

Wear and corrosion at taper junctions of orthopaedic endoprostheses remain of great concern and are associated with adverse clinical reactions. Whereas tribocorrosion of hip tapers was extensively investigated, there is only little knowledge regarding the clinical performance of modular total shoulder prostheses. This retrieval study evaluated 35 modular taper junctions of anatomical shoulder explants using stereomicroscopy, confocal microscopy, as well as optical and scanning electron microscopy to determine the damage modes as well as the effects of taper topography and alloy microstructure. Among all humeral head tapers, 89% exhibited material degradation. Different overlapping wear mechanisms were identified such as plastic deformation, adhesive material transfer, microploughing, and fretting damage. Only CoCrMo cast alloy heads showed a susceptibility to electrochemically dominated fretting in comparison to CoCrMo wrought alloy. Moreover, corundum blasted stem tapers show a significantly increased incidence rate for microploughing. To date, this is the most comprehensive study on the damage types of modular taper junctions of anatomical shoulder arthroplasty proving the existence of fretting even on less weight-bearing implants. This study revealed critical fretting factors, such as the surface finish and the alloy type that are essential for the development of countermeasures that avoid any taper corrosion.

Critical role for syndecan-4 in dendritic cell migration during development of allergic airway inflammation.

Syndecan-4 (SDC4), expressed on dendritic cells (DCs) and activated T cells, plays a crucial role in DC motility and has been shown as a potential target for activated T-cell-driven diseases. In the present study, we investigate the role of SDC4 in the development of T-helper 2 cell-mediated allergic asthma. Using SDC4-deficient mice or an anti-SDC4 antibody we show that the absence or blocking of SDC4 signalling in ovalbumin-sensitized mice results in a reduced asthma phenotype compared with control animals. Most importantly, even established asthma is significantly decreased using the anti-SDC4 antibody. The disturbed SDC4 signalling leads to an impaired motility and directional migration of antigen-presenting DCs and therefore, to a modified sensitization leading to diminished airway inflammation. Our results demonstrate that SDC4 plays an important role in asthma induction and indicate SDC4 as possible target for therapeutic intervention in this disease.

Hammada scoparia flavonoids and rutin kill adherent and chemoresistant leukemic cells.

In search for compounds able to reduce cell adhesion-mediated drug resistance (CAM-DR), we studied effects of Hammada scoparia extracts on leukemic cells adherent or in suspension. We show that H. scoparia flavonoidic fraction and its compound rutin induce apoptosis specifically in adherent leukemic cells and abolish CAM-DR. Importantly, rutin inhibited survival of adherent leukemic progenitors (CD34(+)38(-)123(+)) but spared normal progenitors (CD34(+)38(-)). The pro-apoptotic effects of rutin were correlated with a decrease of active GSK3ß and inhibitors of GSK3ß reproduced rutin-induced cytotoxicity. This study uncovers the potential of H. scoparia flavonoids and rutin to overcome CAM-DR in acute myeloid leukemia.