A Comparison of Consumption and Recovery Profiles According to Anaesthetic Circuit Mode using a New Multifunctional Closed-Circuit Anaesthesia System during Desflurane Anaesthesia: A Clinical Study

This clinical study compared induction time, consumed anaesthetic dose, and haemodynamic and recovery profiles when using a new type of multifunctional anaesthesia machine (Zeus®) in semi-closed or closed circuit modes. Sixty female patients undergoing gynaecological surgery were randomly assigned to three groups and received desflurane anaesthesia through a semi-closed circuit (SCC) at fresh gas flow rates of 4 l/min (SCC 4 l/min) or 2 l/min (SCC 2 l/min), or through a closed circuit (CC). Anaesthesia was maintained at the minimum alveolar concentration for blocking the adrenergic response to painful stimulus (MACBAR) (4.6% end-tidal desflurane) during each operation. The time required to reach MACBAR was significantly shorter and the dose of desflurane was significantly smaller in the CC group compared with the other groups. There were no differences in haemodynamic and recovery profiles between the groups. It is concluded that the CC mode allowed a faster and more reliable induction, lower anaesthetic consumption and stable haemodynamic and recovery profiles.

Expression of DCC in differentiating ameloblasts from developing tooth germs in rats

OBJECTIVE

This study examined the expression pattern of the Deleted-in-colorectal-carcinoma (DCC) gene in developing rat tooth germs.

METHODS

Rat pups at 4, 7 and 10 d postpartum were used in this study. Reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescent localization were used to determine the level of DCC expression during tooth development.

RESULTS

There was more than 2-fold higher level of DCC mRNA in the rat 2nd maxillary molar tooth germs on 10 d postpartum, which was the root stage, than in the rat 3rd maxillary molar tooth germ, which was at the cap/early bell development stage. In addition, the levels of DCC mRNA in the 2nd maxillary molar germs at 4, 7 and 10 d postpartum increased gradually according to tooth development. Interestingly, immunoreactivity against DCC was specifically detected in the differentiating ameloblasts. DCC was observed in the lateral and apical sides of the newly differentiating and secretory stage ameloblasts. Afterwards, DCC was localized only in the apical side of the maturation stage ameloblasts, not in the lateral side.

CONCLUSION

DCC is expressed in the differentiating ameloblasts, which suggests that this molecule plays a crucial role in amelogenesis.

Effect of various implant coatings on biological responses in MG63 using cDNA microarray

During the process of bone formation, titanium (Ti) surface is an important factor in the modulation of osteoblastic function. This study was conducted in order to determine the effects of different Ti surfaces on the biological responses of a human osteoblast-like cell line (MG63). MG63 cells were cultured on smooth (S), sandblasted large-grit and acid etching (SLA), hydroxyapatite (HA), hydroxyfluoride (HF), titanium nitrate (TIN), and diamond-like carbon (DLC) Ti. The morphology of these cells were assessed by SEM. The cDNAs prepared from the total RNAs of the MG63 were hybridized into a human cDNA microarray (1152 elements). The appearances of the surfaces observed by SEM were different on each of the six dental substrate types. The SLA and HA surfaces were determined to be rougher than the others. MG63 cells cultured on SLA and HA exhibited cell-matrix interactions. In the expression of genes involved in osseointegration, several genes, including bone morphogenetic protein, cadherin, integrin, and insulin-like growth factors, were upregulated on the different surfaces. Several genes, including fibroblast growth factor receptor 4, Bcl 2-related protein, and collagen, were downregulated on the different surfaces. The attachment and expression of key osteogenic regulatory genes were enhanced by the surface roughness of the dental materials used.