Synthesis of Ba2SiO4:Eu(2+) by a Hybrid Process and Its Luminescent Properties.

Ba2SiO4:Eu(2+) powders were prepared using a sol-gel-combustion (hybrid) process with tetraethyl orthosilicate (TEOS) and colloidal silica (C-SiO2) as Si sources. The effects of the silicon sources and preparation conditions on phase formation and luminescent properties were investigated. The B2S:Eu(2+) powders synthesized with TEOS were composed of the irregular particles, whereas C-SiO2 was more conducive to uniform particle distribution for the Ba2SiO4:Eu(2+) powders, leading to the enhancement of the emission intensity. The photoluminescence spectra of the synthesized powders exhibited broad excitation bands spanning 250 to 450 nm, and strong green-emission bands, whose intensities and positions were heavily dependent on the concentration of Eu(2+) and Sr(2+) substituted for Ba(2+) in Ba2SiO4.

Influence of the washing program on the blood processing performance of a continuous autotransfusion device.

The continuous autotransfusion system has been widely used in surgical operations. It is known that if oil is added to blood, and this mixture is then processed by an autotransfusion device, the added oil is removed and reinfusion of fat is prevented by the device. However, there is no detailed report on the influence of the particular washing program selected on the levels of blood components including blood fat after continuous autotransfusion using such a system. Fresh bovine blood samples were processed by a commercial continuous autotransfusion device using the "emergency," "quality," and "high-quality" programs, applied in random order. Complete blood count (CBC) and serum chemistry were analyzed to determine how the blood processing performance of the device changes with the washing program applied. There was no significant difference in the CBC results obtained with the three washing programs. Although all of the blood lipids in the processed blood were decreased compared to those in the blood before processing, the levels of triglyceride, phospholipid, and total cholesterol after processing via the emergency program were significantly higher than those present after processing via the quality and high-quality programs. Although the continuous autotransfusion device provided consistent hematocrit quality, the levels of some blood lipid components showed significant differences among the washing programs.

Application of cerebral oximetry for a parturient with Takayasu's arteritis undergoing cesarean section -a case report-.

Takayasu's arteritis (TA) is a chronic inflammatory disease involving the aorta. Because TA sometimes involves cerebral arteries, anesthetic debates focus on cerebral monitoring. There is limited evidence as to which cerebral monitoring method is most adequate. Furthermore, there is insufficient evidence to determine which anesthetic technique is better for TA parturients. We experienced the case of a TA parturient who developed transient cerebral ischemia during cesarean section. The patient's TA involved her cerebral arteries, and her regional cerebral oxygen saturation (rSO2) was lower in the left side than in the right side. She complained of speech impairment, tinnitus, and stiffness of the posterior neck when the rSO2 levels dropped. The FloTrac/Vigileo™ system did not correlate with clinical symptoms, but the cerebral oximeter displayed the low oxygen saturation. We recommend the cerebral oximetry for cerebral monitoring in TA parturients who undergo cesarean sections, especially in hemodynamically unstable patients under regional anesthesia or unconscious patients under general anesthesia.

Compartmental modeling and simplified quantification of [¹¹C]sertraline distribution in human brain.

Sertraline hydrochloride (Zoloft®, Pfizer) is an antidepressant drug of the selective serotonin reuptake inhibitor (SSRI). The aims of this study were evaluating its in vivo distribution and kinetic models in human brain. Also, this study was to determine optimal scan duration of dynamic positron emission tomography (PET) for accurate [¹¹C]sertraline kinetic parameters and the feasibility of semi-quantitative approach for assessing distribution volume ratio (DVR). [¹¹C]sertraline dynamic PET and magnetic resonance imaging (MRI) scans were performed in 5 healthy males. Blood sampling were collected for the input function. Tissue time-activity curves (TAC) were obtained in 7 brain regions using MRI. Goodness-of-fit for TAC using simple tissue compartment model (2C2P) and 3-compartment models with irreversible (3C3P) and reversible (3C4P) were compared. Total distribution volume (DV) for each region of interest (ROI) and DVR were calculated. Also, ratio between the standard uptake value (SUV) of each ROI and that of cerebellum (SUVr) was computed and correlated with the DVR. Akaike information criteria analysis showed that the 2C2P was the most suitable model. Average values of K1 (mL/min/g) and k2 (1/min) were 0.54 and 0.012 in putamen. PET scan time longer than 50 min was required for the accurate estimation of DV. SUVr in 50-90 min was well correlated with DVR.

Comparison of the renal safety between carbon dioxide absorbent products under sevoflurane anesthesia: a pilot study.

BACKGROUND: The chemical reaction of carbon dioxide absorbent and sevoflurane is known to produce compound A. However, carbon dioxide absorbents are not controlled by the Food and Drug Administration, but are treated as industrial products in some nations. Moreover, carbon dioxide absorbents differ in their capacities to produce compound A, because their chemical compositions differ. In this study, we compared the renal safety between carbon dioxide absorbent products in patients under sevoflurane anesthesia. METHODS: Eighty patients with no preexisting renal disease undergoing elective gynecologic surgery were randomly assigned to receive sevoflurane or isoflurane anesthesia with one of four carbon dioxide absorbent products (Sodasorblime®, Sodalyme®, Sodasorb®, Spherasorb®) at the same fresh gas flow of 2 L/min. The renal safety was evaluated by changes of blood urea nitrogen (BUN), creatinine and urine N-acetyl-b-glucoseaminidase (NAG)-creatinine ratio at 24 hours and 72 hours after surgery from preoperative level. RESULTS: There was no significant difference in the renal safety indicators between carbon dioxide absorbents during sevoflurane anesthesia (P > 0.05). However, the BUN and urine NAG-creatinine ratios at 72 hours after surgery were higher in isoflurane anesthesia in some carbon dioxide absorbent groups (P = 0.03 and 0.04, respectively). CONCLUSIONS: We could not find significant differences of renal safety indicators with carbon dioxide absorbents. Although the adverse effect of carbon dioxide absorbents on renal function was not proved, consideration should be given to their contol by the regulation on their efficacy and safety because carbon dioxide absorbents can produce compound A.

Effect of airway pressure on lumbar epidural pressure during positive pressure ventilation.

BACKGROUND: The purpose of this study was to measure lumbar epidural pressure (EP) during the insertion of a Tuohy needle under general anesthesia and to evaluate the influence of airway pressure on EP. METHODS: Lumbar EP was measured directly through a Tuohy needle during intermittent positive pressure ventilation in fifteen patients. Mean and peak EP were recorded after peak inspiratory pressures (PIP) of 0, 15, and 25 cmH(2)O. RESULTS: All measured lumbar EPs were positive, with the pressure increasing during inspiration and decreasing during expiration. Median EP was 6.0 mmHg (interquartile range, 4.0-8.0) at 0 cmH(2)O of PIP, 6.5 mmHg (4.5-8.5) at 15 cmH(2)O, and 8.5 mmHg (6.0-10.5) at 25 cmH(2)O, increasing significantly at 15 cm H(2)O PIP, and further increasing at 25 cmH(2)O (P < 0.001). CONCLUSIONS: We demonstrate the influence of increased airway pressure on lumbar EP measured directly through a Tuohy needle. Lumbar EPs were positive, and increasing PIP levels significantly increased lumbar EP.

The neurological safety of epidural parecoxib in rats.

Epidural injection of cyclooxygenase-2 inhibitors has been suggested as a useful therapeutic modality in pain management in animal studies and clinical settings. Direct epidural administration of parecoxib, a highly selective cyclooxygenase-2 inhibitor, may have advantages over its parenteral administration regarding required dose, side effects, and efficacy. However, no animal studies have been performed to investigate the possible neurotoxicity of epidurally injected parecoxib. Therefore, the present study was performed to assess the neurotoxicity of epidurally injected parecoxib in rats. Rats (n=45) were randomly divided into three groups: normal saline group (group N, n=15), ethanol group (group E, n=15), and parecoxib group (group P, n=15). 0.3 mL of epidural parecoxib (6 mg) and the same volume of epidural ethanol or normal saline were injected into the epidural space. Neurologic assessment was performed 3, 7 and 21 days after the injection by pinch toe testing. Histologic changes were evaluated for vacuolation of the dorsal funiculus, chromatolytic changes of the motor neurons, neuritis, and meningeal inflammation. All rats in groups N and P showed normal response to pinch-toe testing and had a normal gait at each observation point. Histological examination showed no evidence suggestive of neuronal body or axonal lesions, gliosis, or myelin sheet damage in group N or P at any time. However, all rats in group E showed sensory-motor dysfunction, behavioral change, or histopathological abnormalities. No neurotoxicity on the spinal cord or abnormalities in sensorimotor function or behavior was noted in rats that received epidural parecoxib.