Two series of novel, four-arm, star-shaped polypeptides were prepared via the ring-opening polymerization of ␥-benzyl-L-glutamate N-carboxyanhydride and ⑀-benzyloxycarbonyl-L-lysine N-carboxyanhydride with a tetra-amino-substituted perylene fluorophore as the initiator. The removal of the ␣-amino acid side-chainprotecting groups resulted in unprecedented water-soluble, perylene-functionalized, star-shaped polypeptides that showed strong fluorescence in aqueous solution. One of the features that distinguished these water-soluble star polypeptides from most other star polymers was that the conformation of the arms could be reversibly changed from a random coil into an ␣ helix by variations in the pH of the aqueous solution. These star polypeptides might be of interest for the development of novel fluorescent probes or as traceable, stimuli-sensitive molecular containers.
Three-dimensional (3D) printing technologies can be widely used for producing detailed geometries based on individual and particular demands. Some applications are related to the production of personalized devices, implants (orthopedic and dental), drug dosage forms (antibacterial, immunosuppressive, anti-inflammatory, etc.), or 3D implants that contain active pharmaceutical treatments, which favor cellular proliferation and tissue regeneration. This review is focused on the generation of 3D printed polymer-based objects that present antibacterial properties. Two main different alternatives of obtaining these 3D printed objects are fully described, which employ different polymer sources. The first one uses natural polymers that, in some cases, already exhibit intrinsic antibacterial capacities. The second alternative involves the use of synthetic polymers, and thus takes advantage of polymers with antimicrobial functional groups, as well as alternative strategies based on the modification of the surface of polymers or the elaboration of composite materials through adding certain antibacterial agents or incorporating different drugs into the polymeric matrix.
Reinfusion of ultrafiltrate through an uncoated charcoal cartridge proved to be a safe, well-tolerated and simple technique. Further potential benefits of regenerated ultrafiltrate may also include the maintenance of acid-base balance with reinfusion of endogenous bicarbonate.
We described the fabrication of functional and microstructured surfaces from polymer blends by spray deposition. This simple technique offers the possibility to simultaneously finely tune the microstructure as well as the surface chemical composition. Whereas at lower polymer concentration, randomly distributed surface micropatterns were observed, an increase of the concentration leads to significant changes on these structures. On the one hand, using pure homopolystyrene fiber-like structures were observed when the polymer concentration exceeded 30 mg/mL. Interestingly, the incorporation of 2,3,4,5,6-pentafluorostyrene changed the morphology, and, instead of fibers, micrometer size particles were identified at the surface. These fluorinated microparticles provide superhydrophobic properties leading to surfaces with contact angles above 165°. Equally, in addition to the microstructures provided by the spray deposition, the use of thermoresponsive polymers to fabricate interfaces with responsive properties is also described. Contact angle measurements revealed variations on the surface wettability upon heating when blends of polystyrene and polystyrene-b-poly(dimethylaminoethyl methacrylate) are employed. Finally, the use of spraying techniques to fabricate gradient surfaces is proposed. Maintaining a constant orientation, the surface topography and thus the contact angle varies gradually from the center to the edge of the film depending on the spray angle.
Introduction There is only a unique report with a small sample size studying hydroxychloroquine (HCQ) retinal toxicity with swept-source (SS) optical coherence tomography angiography (OCTA). The aim of this study was to quantify OCTA quantitative parameters in patients who underwent HCQ therapy. Methods We conducted a retrospective study. The study included 43 eyes of 22 patients taking HCQ for more than 5 years (high-risk group), 57 eyes of 29 patients taking HCQ for 5 years or less (low-risk group) and 25 eyes of 50 age-matched healthy controls. OCTA quantitative parameters (vessel density (VD) and foveal avascular zone (FAZ) area in superficial capillary plexus (SCP), middle capillary plexus (MCP), deep capillary plexus (DCP), total capillary plexus (TCP), and choriocapillaris (CC)) were recorded. Results In the low-risk group, VD in the SCP and MCP was increased compared to control group ( p value <.05). In the high-risk group, VD in the SCP, MCP and TCP was increased ( p value <.05). The subgroup analysis revealed an increased VD at SCP in systemic lupus erythematosus (SLE) high-risk patients, an increased VD at TCP and CC in rheumatoid arthritis (RA) high-risk subjects, and a decreased VD at CC level in the high-risk group patients with Sjögren's syndrome (SS) and connective tissue disease (CTD) ( p value <.05). Furthermore, we demonstrated a significant enlargement of FAZ area at MCP level in the high-risk group patients with SS and CTD ( p value <.05). Conclusion We demonstrated an increase of VD in patients who underwent HCQ treatment, so we suggest that HCQ retinal toxicity is not vascular mediated.
Introduction: There are a few reports investigating the treatment of aneurysmal type 1 neovascularization (AT1) in Caucasian patients. The aim of this study is to evaluate the 2-year results of a treat and extend regimen with aflibercept in Caucasian patients with AT1. Methods: We conducted an observational retrospective study in 28 eyes of 26 patients with naïve AT1 treated with a treat an extend regimen of intravitreal aflibercept. Best corrected visual acuity (BCVA), central macular thickness (CMT), pigment epithelium detachment (PED) height, presence of dry macula, and regression rate of polypoidal lesions were assessed at baseline and at 12 and 24 months. Results: BCVA was significantly increased by 9.03 ± 16 letters ( p < 0.01) and 9.2 ± 16.87 letters ( p < 0.01) after the 12 and 24 months follow-up. A significant decrease of CMT was found at 12 and 24 months ( p < 0.01). Nevertheless, significant changes in PED height were not observed (0.1 < p > 0.05). At 12 and 24 months of follow-up, dry macula was achieved in a total of 10 eyes (35.71%) and 15 eyes (53.57%). The regression rate of polypoidal lesions was 25% (7 eyes) and 35.71% (10 eyes) after 12 and 24 months. The mean number of intravitreal injections was 7.81 ± 3.20 the first year and 6.11 ± 3.49 the second year. Conclusion: To the best of our knowledge, treat and extend regimen with intravitreal aflibercept in Caucasian patients may be effective for improving BCVA, CMT, wet macula, and regression rate of polypoidal lesions.
Introduction The aim of our study is to report swept-source optical coherence tomography angiography (SS-OCTA) quantitative parameters of retinal and choroidal microvasculature in patients with systemic hypertension (HTN) using a built-in software of SS-OCTA. Methods We performed a retrospective study. This study enrolled 93 eyes of 51 subjects with HTN and 71 eyes of 38 healthy subjects. OCTA quantitative parameters (vessel density (VD) and foveal avascular zone (FAZ) area of superficial capillary plexus (SCP), middle capillary plexus (MCP), deep capillary plexus (DCP), total capillary plexus (TCP) and choriocapillaris (CC)) of the OCTA cube of 4,5 mm × 4,5 mm were recorded. Results A decrease of parafoveal VD in CC, DCP and TCP were demonstrated between HTN group and control group ( p < 0,05). Conversely, no differences were demonstrated in parafoveal VD of SCP and MCP ( p > 0,05). Subgroup analysis revealed a diminution of central VD at SCP, DCP and TCP in patients taking one antihypertensive drug compared to patients treated with two medications ( p < 0,05). Correlation analysis showed a significant, albeit weak, negative correlation between HTN duration, and parafoveal VD in the SCP and FAZ area at SCP, DCP and TCP ( p < 0,05 and r < 0,300). Conclusion When normative data are available, OCTA might be used as a potential tool in the prevention and follow-up of end-organ damage secondary to HTN. Nonetheless, further studies are needed to confirm this hypothesis.
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