Self-Assembly of Unfunctionalized Nanoparticles in Crystallization of Liquid Crystal Trimers.

The crystallization of liquid crystal (LC) trimer-nanoparticle blends resulted in the formation of striped patterns in the crystals. The stripes were initially blurry but became sharper in the nematic LCs formed with heating. When the striped patterns began to collapse, many micron-scale colloidal particles were found out. Both the colloidal particles and stripes disappeared after an increase of 1.0-1.5 °C beyond the temperature at which the colloidal particles appeared. These results suggested that the stripes consisted of the colloidal particles. The distance between stripes depended on the shapes and sizes of the colloidal particles and the cooling rate during the crystallization. There were two melting peaks on the DSC chart of the LC trimer-nanoparticle blends. The two peaks corresponded to the melting of the LC trimers and the disappearance of the colloidal particles, respectively. On the basis of these data, we think that the colloidal particles are composed of hybrid structures in which LC trimers enclose the nanoparticles. The relationship between the striped patterns and the colloidal particles is discussed.

Infusion rate of propofol and jugular venous oxygen saturation.

We compared jugular venous blood oxygen saturation (Sj(O) (2)) and the arterial-to-jugular-bulb venous oxygen content difference (AjD(O) (2)) between bispectral index (BIS) values of 40 and 60, adjusted by the infusion rate of propofol. Eighteen postoperative neurosurgical patients (Glasgow Coma Scale [GCS] scores, 11-15) were enrolled. Normocapnia, normothermia, and a mean arterial blood pressure greater than 70 mmHg were maintained. At BIS values of 40 and 60, hemoglobin, oxygen saturation, and the oxygen partial pressure of arterial and jugular venous blood were measured. Sj(O) (2) at BIS40 (58 +/- 9%) was significantly (P < 0.01) lower than that at BIS60 (63 +/- 10%), and AjD(O) (2) at BIS40 (6.3 +/- 1.5 ml.dl(-1)) was significantly (P < 0.01) higher than that at BIS60 (5.7 +/- 1.5 ml.dl(-1); mean +/- SD). At BIS40, status defined as Sj(O) (2) less than 50% was observed in 3 patients, while this status was observed in 1 patient at BIS60. In conclusion, in patients with postoperative neurosurgical surgery (GCS scores, 11-15), decreases of propofol infusion to adjust the BIS value from 40 to 60 increase the cerebral oxygen balance.

[Spinal anesthesia with isobaric 0.5% bupivacaine for lower limb surgery: effects of different volumes].

BACKGROUND: The effects of different volumes (2.4, 2.6, 2.8 and 3.0 ml) of isobaric 0.5% bupivacaine used for spinal anesthesia were compared in 206 patients scheduled for lower limb surgery. METHODS: The spinal anesthesia was performed with the patients in the lateral position and the isobaric 0.5% bupivacaine was injected intrathecally at the L3-4 interspace. RESULTS: The time to maximum cephalad spread of anesthesia (loss of cold sensation) varied between 25 and 40 min. A significant difference was found in cephalad spread between 2.4 ml group and 3.0 ml group (T11 vs T7), and between 2.6 ml group and 3.0 ml group (T11 vs T7). Severe hypotension did not occur during the study. CONCLUSIONS: Spinal anesthesia with 2.8 ml of isobaric 0.5% bupivacaine proved satisfactory for lower limb surgery.

Common bile duct stone caused by a fish bone: report of a case.

Investigations to determine the cause of jaundice in an 83-year-old man led to the diagnosis of incomplete obstruction of the common bile duct due to stone formation around an ingested fish bone. Abdominal ultrasound and computed tomography performed preoperatively revealed evidence of chronic cholecystitis with a gallstone and calcification in the common bile duct. Endoscopic retrograde choangiopancreatography showed stone formation in the common bile duct. After normalizing the serum bilirubin level by endoscopic retrograde bile duct drainage, we performed cholecystectomy and choledocholithotomy, which revealed stone formation around an ingested bone in the common bile duct. To the best of our knowledge based on a computer-assisted search, this is only the third report of the formation of a choledocal stone around an ingested fish bone. We reviewed the literature on choledocholithiasis caused by a foreign body, in an attempt to classify this entity according to the pathways through which a foreign body can migrate into the common bile duct.

[Postoperative nausea and vomiting after open heart surgery].

We investigated the incidence of the postoperative nausea and vomiting (PONV) following cardiac surgery with cardiopulmonary bypass. We conducted a prospective study of 65 cases with direct interviews by anesthesiologists who are blind to this protocol every 6 hours during ICU stay. There were no differences in age, body mass index, dose of fentanyl, operating time, cardiopulmonary bypass time and ventilation time in ICU between PONV(+) and PONV(-). Incidence of PONV was 43%, but 70% of female patients complained of PONV. Prophylactic antiemetic strategy might be clinically relevant to female patients who are to undergo open heart surgery with cardiopulmonary bypass.