RESUMEN
Iron tetranitro-phthalocyanine was synthesized by the reaction of 4-nitrophthalimide with FeCl3, and was then modified by γ-(trimethoxysilyl)propane-1-thiol to prepare functionalized iron phthalocyanine. A graphene oxide/iron phthalocyanine composite was then prepared, comprising functionalized iron phthalocyanine supported on the surface of graphene oxide via covalent bonds. All these complexes were characterized by infrared spectra (IR), X-ray diffraction, ultraviolet/visible (UV/vis) and Raman spectroscopy, and scanning electron microscopy. The catalytic properties of the graphene oxide/iron phthalocyanine composite for catalyzing adrenaline oxidation were evaluated by measuring the absorbance intensity at the characteristic peak of the oxidation product. A fiberoptic adrenaline sensor based on a graphene oxide/iron phthalocyanine composite catalyst and fluorescence quenching was fabricated and studied. The relationship between the concentrations of dissolved oxygen and adrenaline was investigated by measuring the phase delay φ. The results showed that the graphene oxide/iron phthalocyanine composite can effectively catalyze adrenaline oxidization, and the optimal conditions are pH = 8.0, T = 30 °C, and mGO-FePc = 4.0 mg/mL; moreover, concentrations of adrenaline can be detected in the range from 1.8×10-6 to 9.2×10-5 mol/L with a sensor response time of 4 min.
RESUMEN
Aggregation of liposomal platelet substitutes with activated platelets is the primary endpoint to estimate hemostatic potential. Although light transmission aggregometry is a "gold standard" in assessing platelet aggregation in vitro, this method is less specific and sensitive when tested using liposomal platelet substitutes. In the current study, a new method is developed to evaluate the function of platelet substitutes. By labeling liposomes with a fluorescent dye, DiD, we evaluated their ability to target platelet aggregates using a fluorescence microscope. By incorporating an image-based 96 microtiter microplate, this method was optimized by varying the final lipid concentrations and washing times and validated using unmodified liposomes (e.g., L550 with 0 mol% of carboxylic headgroup lipid; L551 with 9 mol% of carboxylic headgroup lipid) and modified liposomes (e.g., H12-L551 with 9 mol% of carboxylic headgroup lipid and 0.3 mol% of dodecapeptide). Our results showed that 200 µM of H12-L551 liposomes and four washes represent optimal conditions for quantitative fluorescence imaging. This method allowed users to qualitatively observe the fluorescently labeled liposomes involved in platelet aggregates. The imaging analysis tool was sufficiently sensitive to quantitatively determine the significantly enhanced delivery of the modified liposomes to platelet aggregates. This enhancement was achieved using dodecapeptide, which specifically binds to activated platelets. This robust and high-throughput method enables the evaluation of liposome function and should facilitate the development of platelet substitutes with a greater ability to target platelet aggregates.
RESUMEN
BACKGROUND: Primary hypertrophic osteoarthropathy (PHO), also known as pachydermoperiostosis is a rare genetic disease which predominantly affects skin, bone and soft connective tissue. It is characterized by the triad of pachydermia, digital clubbing and periostosis of long bones. Arthralgia or arthritis is also present in most of the cases. Genetic studies have identified the impaired PGE2 metabolism as a culprit for hypertrophic osteoarthropathy in PHO cases. We conducted a systematic review to examine the effectiveness of Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), a PGE2 synthesis blocker to reduce the symptoms among PHO patients. METHODS: We searched the evidence in five databases; Cochrane Library, CINAHL, EMBASE, MEDLINE, and PubMed. We reported the evidence using narrative synthesis. RESULTS: Out of 238 identified studies, we selected 26 for the synthesis. All were case reports which included a total of 54 patients. Among them, 39 patients were treated with at least one type of NSAIDs. Around 70% of the patients treated with NSAIDs had clinical improvement for their symptoms, mostly arthritis or arthralgia symptoms. CONCLUSION: NSAIDs were effective in improving arthralgia or arthritis symptoms in majority of the PHO patients. Therefore, we recommend the use of NSAIDs in PHO patients to treat arthralgia or arthritis.