Bone-Forming Effect of a Static Magnetic Field in Rabbit Femurs.

This study investigated the level of magnetic energy around implants possessing a static magnetic field (SMF) and assessed the in vivo influence of SMF on bone regeneration. Implants possessing a sintered neodymium magnet internally were placed in a rabbit femur. An implant without SMF was placed as control. After 12 weeks of healing in vivo, the bone samples were subjected to histologic/histomorphometric evaluation. The bone-to-implant contact for the test group and the control group were 32.4 ± 13.6% and 17.1 ± 4.5%, respectively, and the differences were statistically significant (P < .05). The results suggested that the SMF promoted new bone apposition.

[A new method for evaluating the degree of eyestrain: a comparison between color and monochrome liquid crystal display monitors].

Color and monochromatic liquid crystal displays (LCDs) were compared in terms of eyestrain by using a new method that uses Landolt rings for a visual perceptional test. In this method, the difference of the nearest distances to distinguish Landolt rings between before and after the usage of LCD monitors was used as the index of eyestrain. When the nearest distance for distinguishing Landolt rings increased, the eyestrain was considered to be severe. A total of 11 observers (2 physicians and 9 radiological technologists) participated to this observer study. In the observer study, the TG18-QC pattern, a standard clinical image of 400 images, and JESRA X-0093 were observed using color and monochromatic LCD monitors for approximately 30 minutes. In addition to the observer study, the noise power spectrum (NPS) of the color and the monochromatic monitors were measured using the NS2002 method. The ratio of the nearest distance after 30 minutes of reading and that of before reading was larger when the color LCD monitor was used than when the monochromatic LCD monitor was used (p<0.05), and thus, the monochromatic LCD monitor was considered to be superior to the color LCD monitor in terms of the degree of eyestrain during image readings. In conclusion, comparing the nearest point for distinguishing Landolt rings measured before and after readings can be used to evaluate eyestrain in diagnostic radiology.

X-ray diffractometer designed for industrial applications at SPring-8 BL24XU.

An X-ray diffractometer for industrial applications has been designed, installed at SPring-8 BL24XU and tested by measuring a standard Al(2)O(3) powder sample. The measurement results prove the high precision of the diffractometer. The diffractometer was also tested by conducting grazing-incidence X-ray diffraction measurements of ion-implanted chromium-coated steel. The validity of a new method for X-ray stress measurements of polished stainless steel is also proposed and confirmed. The results prove the suitability of this diffractometer for industrial applications.

The presence of candidate tumor suppressor gene loci at chromosome 3p for oral squamous cell carcinomas.

We investigated the short arm of chromosome 3 (3p) for allelic imbalances, including loss of heterozygosity (LOH) and microsatellite instability (MSI) in 40 primary oral squamous cell carcinomas (SCCs) using 10 microsatellite markers and constructed a deletion map for this chromosome arm. We examined 40 primary tumor tissues, 40 corresponding normal tissues, and seven lymph node metastatic tissues. LOH at one or more loci was found in 24/40 (60%) of tumors. Deletion mapping of these tumors revealed at least three discrete, commonly deleted regions on the chromosome arm. Furthermore, we detected MSI in six of those tested cases (15%). We compared our results with the clinicopathologic features. A number of sites displaying LOH at 3p could be detected in early stage lesions, and the frequencies of LOH tended to be higher in later clinical stages. Thus, the frequent LOH was observed from early stage in pTNM classification. An unknown tumor suppressor gene in the genesis of oral squamous cell carcinoma may exist in 3p.