Calcium level-responsive in-vitro zinc release from zinc containing tricalcium phosphate (ZnTCP).

The in vitro Zn release from tricalcium phosphate containing Zn (ZnTCP; 0.63, 6.17, and 12.05 Zn w/w%) was investigated. The rates of release from ZnTCP powders were measured in 25 mL of simulated body fluid (SBF) containing 10 mg/100mL Ca (SBF/H), 5 mg/100mL Ca (SBF/L), or no Ca (SBF/-) at pH 7.25, 37.0+/-0.1 degrees C. The release from 6 and 12% ZnTCP was initially very fast. The rate of release from ZnTCP decreased as the concentration of Ca in the dissolution media increased, but increased as concentration of Zn in TCP increased. The dissolution kinetics of ZnTCP followed the Hixon-Crowell equation at the initial stage of dissolution, and the initial dissolution rate constant (IDR) was calculated by the least-squares method. The effect of Ca concentration on percent IDR of ZnTCP suggested that Zn release from 0.6% ZnTCP was significantly high compared to that from 6 or 12% ZnTCP. The relationship between the amount of Ca precipitated and Zn release of various ZnTCP samples suggested that the release from 0.6% ZnTCP was significantly different compared to that from 6 and 12% ZnTCP, consistent with the data for percent Zn IDR. X-ray diffraction data suggested that 0.6% ZnTCP contained 5% hydroxyapatite, a low solubility material, which acted as seed crystal during the dissolution test.

[General anesthesia with sevoflurane and vecuronium for patients with dystrophia myotonica and progressive muscular dystrophy].

A 9 year old male previously diagnosed as progressive muscular dystrophy whose serum CPK5430IU.l-1 was very high received general anesthesia. Before anesthesia, dantrolene sodium 2 mg.kg-1 was given. Anesthesia was induced with thiamylal 100 mg and vecuronium bromide 3 mg. Anesthesia was maintained with sevoflurane (0.5%) in nitrous oxide (66%) and oxygen (33%). The course of anesthesia was uneventful. The operative time was 80 minutes. At the end of the operation, the patient recovered smoothly from anesthesia. A 46 year old female with dystrophia myotonia also received general anesthesia. The patient was diagnosed as having this disease 26 years previously. Preoperatively, the patient was suspected to have cardiac damage. Anesthesia was induced with thiamylal 100 mg, fentanyl 100 micrograms, midazolam 5 mg and vecuronium bromide 4 mg, and maintained with sevoflurane (1.0%) in nitrous oxide (66%) and oxygen (33%). Anesthesia was uneventful, but at the end of the operation, the patient could not breath fully by herself. She was placed on a ventilator and observed carefully. The endotracheal tube was removed 150 minutes after the induction of anesthesia. In these two cases, sevoflurane and vecuronium bromide were used safely.

Neurosurgical application of a flow-directed oximetry thermodilution catheter for evaluation of cerebral blood flow--technical note.

The neurosurgical application was evaluated of a flow-directed oximetry thermodilution catheter for measurement of oxygen saturation in the jugular vein, which reflects cerebral blood flow (CBF). The catheter allows estimation of changes in CBF during carotid endarterectomy and therapeutically induced hypertension in the management of delayed vasospasm after subarachnoid hemorrhage.

[Anesthetic management of revascularization for moyamoya disease].

Anesthetic management during 85 STA-MCA anastomoses with or without encephalo-myosynangiosis for 64 patients with Moyamoya disease was evaluated retrospectively. Anesthetic agents included nitrous oxide-NLA (GONLA), nitrous oxide-halothane (GOF), nitrous oxide-enflurane (GOE), and their combinations. Slight hypercarbia (40 mmHg less than PaCO2 less than 50 mmHg) was essential to avoid cerebral ischemia. Several procedures to control heart rate by beta blockade or to control hypertension by nitroglycerin were required, because tachycardia and hypertension interfered with fine surgical procedure. During microsurgery HR of GONLA anesthetized patients was significantly lower. Postoperatively the patients anesthetized by GOE showed significantly lower PaCO2 compared with the GONLA anesthetized patients. So we recommend GONLA for anastomosis in patients with Moyamoya disease.