Pretreatment with antiplatelet drugs improves the cardiac function after myocardial infarction without reperfusion in a mouse model

Background: Reperfusion therapy is known to improve prognosis and limit myocardial damage aftermyocardial infarction (MI). The administration of antiplatelet drugs prior to percutaneous coronaryintervention also proves beneficial to patients with acute MI (AMI). However, a good number of AMIpatients do not receive reperfusion therapy, and it is not clear if they would benefit from antiplateletpre-treatment.Methods: Experimental C57BL/6 mice were randomly allocated to five groups: the sham group,control, post-treatment, pre-treatment, and pre- and post-treatment groups. Acetylsalicylic acid (15 mg/kg), clopidogrel (11 mg/kg), ticagrelor (27 mg/kg), and prasugrel (1.5 mg/kg) were intragastrically administered in the treatment groups. On day 7 post MI, cardiac function and cardiac fibrosis were evaluated using echocardiography and Masson’s trichrome staining, respectively. Histopathological examinations were performed on tissue sections to grade inflammatory cell infiltration. Platelet inhibition was monitored by measuring thrombin-induced platelet aggregation.Results: Left ventricular ejection fraction and fractional shortening improved significantly (p < 0.01)in the pre-treatment groups when compared to the post-treatment and control groups. A significant(p < 0.01) decrease in cardiac fibrosis was observed in the pre-treatment group, compared with the posttreatment and control groups. Inflammatory cell infiltration significantly decreased in the pre-treatment group compared with the control group (p < 0.05). Thrombin-induced platelet aggregation was significantly inhibited by antiplatelet drugs, but increased with the exposure to H2O2.Conclusions: In the absence of reperfusion therapy, pre-treatment with antiplatelet drugs successfullyimproved cardiac function, reduced cardiac fibrosis and inflammatory cell infiltration, and inhibited oxidative stress-induced platelet aggregation after MI in the mouse model

Temperature-insensitive fiber-optic refractometer based on immobilization of polydimethilsiloxane film

A temperature-insensitive fiber refractometer, which consists of a simple single-mode–multimode–single-mode fiber optic scheme, is theoretically proposed and experimentally demonstrated. The multimode section involves with a segment of D-shaped no core fiber (Ds-NCF) while the surface of the Ds-NCF is partially coated with a thin layer of polydimethylsiloxane (PDMS) film. Owing to the opposite thermo-optic coefficients (TOC) of the silica and the PDMS film, a compact structure with nearly zero temperature dependence is fabricated. Moreover, such refractometer benefits from simplicity and low-cost and achieves competitive refractive index sensitivities of 140.1 nm/RIU in the range of 1.32 to 1.37, and_1147 nm/RIU over a RI range from 1.38 to 1.44. These excellent characteristics would find wide potential applications, such as chemical detection, biological detection, medical field and other fields