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Objective: To examine the effects of vasopressors on free flap outcomes. Background: Most micro-surgeons avoid the use of vasopressors during free flap surgery due to concerns of vasoconstriction, which could potentially lead to vascular thrombosis and flap failure. Previous studies lack the statistical power to draw meaningful conclusions. Methods: All free flaps between 2004 and 2014 from a single institution were reviewed retrospectively. Vasopressors were given intraoperatively as an intravenous bolus when blood pressure dropped >20% from baseline. The timing of intraoperative vasopressor administration was divided into 3 phases: from anesthesia induction to 30 minutes before the start of flap ischemia (P1); end of P1 to 30 minutes after revascularization (P2); end of P2 to end of surgery (P3). Agents included phenylephrine, ephedrine and calcium chloride. Results: A total of 5671 free flap cases in 4888 patients undergoing head and neck, breast, trunk, or extremity reconstruction were identified. Vasopressors were used intraoperatively in 85% of cases. The overall incidence of pedicle compromise was 3.6%, with a flap loss rate of 1.7%. A propensity score matching analysis showed that intraoperative use of any agents at any time of surgery was not associated with increased overall pedicle compromise [51/ 1584 (3.2%) vs 37/792 (4.7%); P = 0.074] or flap failure rates [26/1584 (1.6%) vs 19/792 (2.4%); P = 0.209]. Rather, there was less risk of venous congestion [33/1584 (2.1%) vs 31/792 (3.9%); P = 0.010]. Conclusions: Intraoperative use of phenylephrine, ephedrine, or calcium chloride as an intravenous bolus does not increase flap compromise and failure rates in cancer patients. [ABSTRACT FROM AUTHOR]

The article presents a study which explores the neuroprotective effects and mechanisms of penehyclidine hydrochloride on cerebral ischemia-reperfusion injury in rats. The penehyclidine hydrochloride effect on N-methyl-D-aspartate receptors in neurons in hippocampus after oxygen-glucose deprivation was also examined. The findings show that penehyclidine hydrochloride could attenuate oxidative stress injury and neuronal apoptosis following cerebral ischemia-reperfusion.

Lu3Ga5O12Eu3+, Lu3Ga5O12Tb3+, and Lu3Ga5O12Pr3+, phosphors were prepared through a Pechini-type sol-gel process. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), photoluminescence, and cathodoluminescence spectra were utilized to characterize the synthesized phosphors. The XRD results reveal that the sample begins to crystallize at 800°C and fully crystallined pure Lu3Ga5O12 phase can be obtained at 1000°C. The FESEM image indicates that the phosphor sample is composed of aggregated rice grainlike particles with sizes around 80-120 nm. Under the excitation of ultraviolet light (250-275 nm) and low-voltage electron beams (1-3 kV), the Lu3Ga5O12Eu3+, Lu3Ga5O12Tb3+, and Lu3Ga5O12Pr3+ phosphors show the characteristic emissions Eu3+ (5D0 → 7F4,3,2,1 transitions, orange-red), Tb3+ (5D4 → 7F6,5,4,3 transitions, green), and Pr3+ (³P0 → ³H4, ³P1 → ³H5, ³P0 → ³H5, and ¹D2 → ³H4 transitions, green), respectively. The corresponding luminescence mechanisms are discussed. These phosphors have potential applications in area of field emission displays. [ABSTRACT FROM AUTHOR]

Trivalent dysprosium (Dy3+)-activated β-gallium oxide (β-Ga2O3) phosphors were synthesized by solid-state (SS), coprecipitation (CP), and citrate gel (CG) methods, respectively. The resulting β-Ga2O3:Dy3+F phosphors were well characterized by X-ray diffraction, field-emission scanning electron microscopy (FESEM), and by photoluminescence and cathodoluminescence spectra. The phosphors prepared by different methods show different luminescence properties under the excitation of UV and low-voltage cathode rays. There exists an energy transfer from the β-Ga2O3 host lattices to Dy3+, and the energy transfer efficiency was higher in the CG-derived phosphors than those of the SS- and CP-derived phosphors. Factors influencing the intensity of luminescence and the energy transfer efficiency from β-Ga2O3 host to Dy3+ in β-Ga2O3:Dy3+ phosphors were investigated in detail. It is shown that the CG method is the most respected process for the preparation of β-Ga2O3:Dy3+ phosphors. [ABSTRACT FROM AUTHOR]