An association between the MICA-A5.1 allele and an increased susceptibility to oral squamous cell carcinoma in Japanese patients.

BACKGROUND: Recently, a new polymorphic gene family called the major histocompatibility complex class I chain-related gene A (MICA) was discovered about 40 kb centromeric to HLA-B gene. The MICA protein, expressed on epithelial cells and many kinds of tumor cells, serves to regulate immune function. The MICA protein is thought to activate immune function on mucosal tissue by binding to NKG2D which is expressed on most natural killer cells, CD8 positive T cells, and gamma delta T cells. An association between MICA gene polymorphisms and the development of oral squamous cell carcinoma (OSCC) has also been reported. OBJECTIVE: This study was designed to test this association in Japanese patients with OSCC. METHODS: The (GCT)(n) polymorphisms of the MICA gene was investigated in 123 patients with OSCC and 188 normal controls using polymerase chain reaction amplification and denaturing polyacrylamide gel electrophoresis. RESULTS: Five alleles, namely A4, A5, A6, A9, and A5.1, were found in both groups. The phenotype frequency of the MICA-A5.1 allele was significantly higher in patients with OSCC when compared with normal controls (OR 1.707, 95% CI 0.76-3.45, P=0.042). Also, the microsatellite frequency of the MICA-A5.1 allele was significantly higher in patients with OSCC compared with normal controls (OR 1.664, 95% CI 0.82-3.42, P=0.021). Lastly, the frequency of the MICA-A5.1 allele was significantly higher in those with lymph node metastasis from OSCC compared with normal controls (OR 2.605, 95% CI 1.14-5.27, P=0.026). CONCLUSIONS: These results suggest that the MICA-A5.1 allele may be associated with an increased susceptibility to OSCC in Japan.

Clinical analysis of isolated zygomatic arch fractures.

PURPOSE: The purpose of this study is to analyze the characteristics of isolated zygomatic arch fractures and to evaluate the functional and radiological outcomes of the treatment. PATIENTS AND METHODS: Forty patients with isolated zygomatic arch fractures were analyzed clinically. RESULTS: The patients were 25 males and 15 females with an average age of 42 years. The cause of injury was traffic accident in 26, followed by fall in 8, sports in 3, and assault in 3. The left side was involved in 25 cases. Fractures were classified into 5 types according to the degree of displacement and loss of bone contact. Reduction was performed in 31 patients, 26 treated by the Gillies temporal approach. Conservative treatment was chosen in 9 patients. The reduction status was excellent in 12 cases, good in 17 cases, and fair in 2 cases. There was no difference in the reduction status in terms of the fracture types or the interval between reduction and injury. Interincisal distance (IID) at maximal mouth opening recovered from 33.4 to 43.8 mm by excellent reduction, from 26.2 to 42.2 mm by good reduction, from 27.5 to 40 mm by fair reduction, and from 41 to 46.6 mm by conservative treatment. CONCLUSIONS: Good functional and radiological outcomes were obtained in isolated zygomatic arch fractures. Reduction status was not influenced by either the fracture type or the interval between reduction and injury, and recovery of IID was similarly achieved by excellent, good, and fair reduction.

Changes in tongue and hyoid positions, and posterior airway space following mandibular setback surgery.

INTRODUCTION: The postural response of the tongue after mandibular setback is clinically important for maintaining normal respiration. Although the hyoid bone moves progressively to adapt physiologically to the altered orofacial configuration following such surgery, it is not clear whether repositioning of the hyoid has an effect on the pharyngeal airway. In the present study, postoperative changes in hyoid position and pharyngeal airway space were assessed retrospectively in patients who had undergone mandibular setback surgery. MATERIAL AND METHODS: Digitized lateral cephalograms from 30 mandibular setback surgery cases taken preoperatively, and 1 month and more than 1 year postoperatively, were used to examine pharyngeal airway morphology and the position of hyoid bone. RESULTS: A significant downward movement of the hyoid bone was found 1 month after surgery, while the pharyngeal airway dimensions at the tongue were maintained. More than 1 year after surgery, the hyoid position returned to its original position, resulting in a significant decrease in retrolingual airway dimension. CONCLUSION: The results indicate that mandibular setback causes airway narrowing late after surgery, while the early postoperative airway dimension is maintained. Long-term observations should be performed because of the changes of oropharyngeal configuration following mandibular setback.

[The influence of intermittent hemodialysis (HD) on bispectral index (scale) (BIS) and serum propofol concentration under postoperative intravenous sedation].

We experienced a case of postoperative intravenous sedation with propofol during intermittent hemodialysis (HD), and investigated the correlation between the clinical sedation level based on bispectral index scale (BIS) together with Ramsay score, and the serum concentration of propofol. One adult oral cancer patient (carcinoma of the lower gingiva) with end-stage renal dysfunction needing HD was selected for this study. The day after operation, HD was commenced under intravenous sedation with propofol. Clinical sedation level was assessed using BIS and Ramsay score, and serum propofol concentrations were determined in arterial blood samples. Serum concentrations were measured every 15 times until 51 hours after operation. The initial dose of propofol was set at 3.5 mg x kg(-1) x h(-1) on the basis of clinical symptoms. According to BIS and Ramsay score, sedation level decreased lineally for 1 hour after commencement of HD. In contrast, serum propofol concentration incresed from 1.71 microg x ml(-1) to 2.21 microg x ml(-1). Total serum concentration of propofol was enhanced during HD because of dialytic dehydration, but, according to BIS and Ramsay scores, the possibility was suggested that the fraction of albmin-unbound propofol with pharmacological activities was eliminated or absorbed by membrane during HD.