A novel measurement method for the morphology of the mandibular ramus using homologous modelling.

OBJECTIVES: It is important to assess the mandibular morphology when orthognathic surgery, especially mandibular ramus osteotomy, is performed. Several studies on three-dimensional (3D) facial asymmetry have reported differences in linear and angle measurements between the deviated and contralateral sides in asymmetric mandibles. However, methods used in these studies cannot analyse the 3D morphology of the ramus. In this study, we aimed to evaluate the differences in mandibular ramus between the deviated and contralateral sides in asymmetric mandibles using traditional measurements as well as 3D shape analysis. METHODS: 15 Japanese females with jaw deformities treated by orthodontic surgery were enrolled. 3D CT images were reconstructed, and 14 landmarks were identified on the model surface. Ten linear and four angle measurements were calculated using these landmarks. Homologous ramus models were constructed for each sample, and after converting all homologous models to the right side, 30 homologous models of the ramus were analysed using principal component analysis. RESULTS: Firstly, eight principal components explained >80% of the total variance. Differences between the deviated and contralateral sides in measurements and scores of the eight principal components were tested. Significant difference at the 5% level between the deviated and contralateral sides was observed in five linear measurements, three angle measurements and the third principal component. The variance of the deviated side was significantly larger in the diameter between the mandibular notch and coronoid process, horizontal dilated angle of the mandibular ramus and vertical dilated angle of the mandibular ramus. The variance of the contralateral side was significantly larger in the height of mandibular ramus, height of posterior of mandibular ramus, condylar width, height of condylar head and mandibular angle. The squared multiple correlation coefficient adjusted for the degrees of freedom was 0.815. The third principal component showed the difference between the deviated and contralateral sides. Shape variation represented by the third principal component visually indicated that the contralateral side was larger and had inwardly directed coronoid process and the deviated side had a mandibular angle that was turned inwards to a greater extent. CONCLUSIONS: In conclusion, we successfully created a homologous model of the mandibular ramus and demonstrated the effectiveness of this model in the 3D comparison of the ramus morphology between the contralateral and deviated sides in asymmetric mandibles.

Successful management of critical limb ischemia with intravenous sodium thiosulfate in a chronic hemodialysis patient.

Vascular calcification is common among hemodialysis (HD) patients and contributes to the development of peripheral arterial disease. A 57-year-old Japanese man who had been on HD for 30 years was referred to us for severe pain with multiple ulcers on his toes and fingers. He was an ex-smoker and had no diabetes mellitus. On admission, he had ulcers on his big toes bilaterally and right 2nd - 4th fingers. Peripheral pulses were strong and his ankle-brachial pressure index was above 1.3. Laboratory data were as follows: calcium 9.9 mg/dl, albumin 3.3 g/dl, phosphate 3.0 mg/dl, Ca x P product 30, and parathyroid hormone 98 pg/ml. He had a parathyroidectomy in 1998 and 1999. X-rays of his hands and legs showed diffuse subcutaneous arteriolar calcification. Angiography revealed no local stenotic lesions. Despite intensive therapies including hyperbaric oxygen therapy, painful gangrene developed on his right big toe and the pain was so intense that he could not go to sleep in a supine position. We infused intravenous sodium thiosulfate (20 g) 3 times weekly, based on previous reports. Within 4 - 5 days, he experienced rapid and dramatic symptom relief. The score of the visual analogue pain scale improved from 10/10 - 2/10. The signs of ischemia, measured by transcutaneous partial oxygen pressure and thermography, improved significantly. During the infusion of sodium thiosulfate, the patient complained of nausea, vomiting and hyperosmia. These adverse symptoms were resolved after discontinuation of the infusion. Pain relief was sustained and he could walk after 2 weeks of infusion. Our case supports the use of sodium thiosulfate as a novel therapeutic choice for critical limb ischemia with severe vascular calcification in chronic HD patients.

Nodular thyroid hyperplasia in a cynomolgus monkey.

Nodular thyroid hyperplasia was found in a 4-year-old male cynomolgus monkey (Macaca fascicularis). The monkey was clinically normal; however, necropsy revealed multiple variably sized nodules in both lobes of the thyroid gland. In contrast to the fairly uniform diameter of the lumen of follicles in the surrounding gland, the diameter of the follicular lumen within the hyperplastic nodules was highly variable and ranged from nonexistent to cystlike. Occasionally, in the larger follicles there were papillary infoldings of epithelium. The hyperplastic nodules were partially encapsulated by a fibrous capsule and showed little compression of the surrounding tissue. The follicular cells and colloid comprising the hyperplastic nodule were immunohistochemically positively stained with the antibody for thyroglobulin. Ultrastructurally, the cells forming follicles had numerous microvilli along the luminal surface, and lysosomal bodies and dilated rough endoplasmic reticulum in the cytoplasm. All these morphologic findings are consistent with nodular thyroid hyperplasia, which is rare in nonhuman primates.

A novel renal carcinoma predisposing gene of the Nihon rat maps on chromosome 10.

A novel rat model of hereditary renal cell carcinoma (RC) was found in a rat colony of the Sprague-Dawley (SD) strain in Japan, and named the "Nihon" rat in 2000. This study was designed to map the RC susceptibility gene in the Nihon rat using 113 backcross animals. Our present data clearly show that the Nihon gene is genetically linked to interleukin-3 (IL3) gene (chi(2) = 93.6, Lod score = 25.16), lethal (2) giant larvae (LLGL1) locus (chi(2) = 109.0, Lod score = 31.56) and myosin heavy chain, embryonic skeletal muscle (MYHSE) gene (chi(2) = 90.6, Lod score = 23.87), which are located on the distal part of rat chromosome 10. The order of the genes is the Eker (Tsc2) gene (located on the proximal part of rat chromosome 10; human chromosome 16p 13.3)--21.3 cM--IL3 gene (human 5q23-31)--4.4 cM--Nihon gene--0.9 cM--LLGL1 locus (human 17p11.2)--4.4 cM--MYHSE gene (human 17p13.1). We also detected loss of the wild-type allele at the MYHSE locus, fitting Knudson's "two hit" model. Thus, the Nihon rat should have a mutation of a novel tumor suppressor gene related to renal carcinogenesis.

A novel "Nihon" rat model of a Mendelian dominantly inherited renal cell carcinoma.

A novel rat model of hereditary renal cell carcinoma (RC) was found in a rat colony of the Sprague-Dawley strain in Japan, and named the rising "Nihon" rat. In this strain, RCs develop from early preneoplastic lesions, which begin to appear at 4 weeks of age, forming adenomas by the age of 16 weeks. The RCs are predominantly of clear cell type. Southern blot, northern blot and SSCP analyses revealed no change in the Tsc1, Tsc2, VHL, and c-Met genes. Thus, the Nihon rat should be a valuable experimental model for understanding renal carcinogenesis, especially clear cell type, which is common among human RCs.

Analysis of 3-D human foot forms using the Free Form Deformation method and its application in grading shoe lasts.

An effective way to design well-fitting products is to analyse human body forms and to classify them into several groups. In the present study, a new method is proposed to analyse human body forms using the FFD (Free Form Deformation) technique. The FFD method is a way to deform the shapes of object smoothly by moving control lattice points set around the object. The reference body form is automatically deformed to coincide with the other body forms using the FFD method. The dissimilarity is defined by the movements of the control lattice points. The foot forms of 56 Japanese adult females were analysed with this method, and distributions for them were calculated using multi-dimensional scaling. The first axis contrasts feet with high dorsal arches and low dorsal arches, and the second axis is related to the antero-posterior proportion of the foot. As an application of the present method, a last of width EEEE was designed from an existing last of width E by applying the control lattice points that converted a representative foot of width E into a foot of width EEEE. The new EEEE width last reflected the allometric differences between narrow and wide feet better than one obtained by a conventional method. It was found that the present method with FFD is not only useful for classifying 3-D human body forms, but also has potential as applications for designing well-fitting products.

Brachycephalization in Japan has ceased.

Somatometric data are presented which show that the rapid brachycephalization in Japan has recently ceased. The causes of brachycephalization are investigated in relation to the secular change in height. Increases in head breadth have been the main cause of brachycephalization, and its pattern of secular change is very similar to that in height. Associations between head breadth, height, and year of birth were examined by partial correlation coefficients and through a comparison of students and the general population. Brachycephalization is thought to result from increases in the growth rate for head breadth caused by improvements in nutritional levels, as seen in increases in height. Increases in height over the last 100 years have been accompanied by brachycephalization in Japanese and Koreans, but by debrachycephalization in many European populations. Increases in lateral growth in Asian heads may be related to the facial flatness which is characteristic to northern Mongoloid populations.

Interobserver errors in anthropometry.

To present basic information on the interobserver precision and accuracy of 32 selected anthropometric measurement items, six observers measured each of 37 subjects once in two days. The data were analyzed by using ANOVA, and mean absolute bias, standard deviation of bias, and mean absolute bias in standard deviation unit were used as measures of bias. By comparing the results of the two days, the effects of the practice on measurement errors were also investigated. Variance was overestimated by more than 10% in five measurements. Interobserver error variance and random error variance were highly correlated with each other. Measures of the bias were significantly correlated with interobserver and especially with random error variances. The interobserver errors were drastically reduced on the second day in the measurement items in which the causes of the interobserver errors could be specified. It was speculated that even when the definitions of the landmarks and measurement items were clear, the ambiguity in the practical procedures in locating landmarks, applying instruments, and so on, permitted each observer to develop his or her own measurement technique, and it in turn caused interobserver errors. To minimize interobserver and random errors, the standardization of measurement technique should be extended to the details of the practical procedures.

Methylene-interrupted double bond in polyunsaturated fatty acid is an essential structure for metabolism by the fatty acid chain elongation system of rat liver.

Some plant oils contain non-methylene-interrupted polyunsaturated fatty acids (NMIFAs). Pinolenic acid (all cis delta-5,9,12/18:3) and columbinic acid (trans,cis,cis delta-5,9,12/18:3) are NMIFAs that exist in pine seed oil and columbine seed oil, respectively. We investigated the double bond position of fatty acid recognized by the fatty acid chain elongation system (FACES) of rat liver using NMIFAs as experimental tools. In the total elongation assay, amounts of C2 unit chain-elongated metabolites of pinolenic acid and columbinic acid were 32% and 11%, respectively, compared to that of gamma-linolenic (all cis delta-6,9,12/18:3) as the substrate. In the condensation reaction assay, the rate limiting step of FACES, the conversion rates of pinolenic acid and columbinic acid to the corresponding C20 beta-keto fatty acids were 19% and 9% of that of gamma-linolenic acid, respectively. The formation of elongated metabolite of podocarpic acid (all cis delta-5,11,14/20:3) was only 7% of that of arachidonic acid (all cis delta-5,8,11,14/20:4). From these results it was concluded that the condensing enzyme of FACES could recognize the methylene-interrupted cis double bond structure vicinal to the carboxyl group in the fatty acid molecule.

Automatic calculation of the medial axis of foot outline and its flexion angles.

As one of the morphological characteristics of human foot, flexion angles of medial axis of foot outline have been proposed in order to improve shoe comfort. Foot outlines were easily obtained by a scriber, whereas calculation of the medial axis and its flexion angles from the foot outline had inter-operator errors and a lack of reproducibility. This is because foot outlines were inputted by a digitizer, and flexion points of the medial axis were determined by eye inspection. An automatic method of calculation was developed for the following purposes: (1) to decrease inter-operator errors caused by manual operation; (2) to improve the reproducibility of the medial axis and its flexion angles; and (3) to save time and trouble in processing a large amount of data. The flexion angle reproducibility of the present method was within 1 degree. The errors in the flexion angles determined by the present method are half those determined by the conventional method. The flexion angles of over 5000 foot outlines that were obtained in 1987 were calculated when the present method was developed. The mean posterior flexion angle of the adults was 8.4 degrees. Since the majority of Japanese feet are outflared, this characteristic should not be ignored in designing/modifying shoe lasts.

Random errors in anthropometry.

In order to present basic information on the magnitude of and variance due to the random error in anthropometry, 219 measurement items were taken on 12 subjects twice by the same observer. The precision (i.e., consistency between the repeated measurements) was investigated for these measurement items. The reliability was quantified using mean absolute difference (MAD), technical error of measurement (TEM), and reliability coefficient (R). MAD and TEM are highly correlated with each other and both represent the magnitude of error. They are not correlated with R, which represents the proportion of error-free variance. Larger measurements tend to have absolutely larger but relatively smaller random errors and higher reliability in the size range of 1-10 cm. Imprecision is inherent in anthropometry of the living because of the fact that the human body is not rigid. This may be responsible for the above tendency. Relatively large MAD and low R may be due to small absolute size, landmarks difficult to locate precisely, soft tissue deformation, and the inconsistency of the posture of the subject.

Analysis of foot shape variation based on the medial axis of foot outline.

The variations in foot outline forms are analyzed by using flexion angles of the medial axis of foot outline. Foot outline and 12 conventional measurements taken on the right foot of 443 male and 297 female subjects with no visible pathological deformation of the foot were used for analyses. The results indicate that the foot is outflared in most of the subjects. Medial bulge and lateral concavity of foot outline are responsible for the foot outflare, and they are not correlated with each other. Medial bulge is due to the overhang of navicular bone that is caused by the pronation of the foot. Its intensity is negatively correlated with dorsal arch height. Lateral concavity is partly due to the abduction of talus and calcaneus relative to the tarsometatarsal bones anterior to them. These three-dimensional morphological characteristics of outflared feet intimately relate to the fit and comfort of the shoe. The flexion angles of medial axis of foot outline provide a useful tool in morphological analysis of the foot for the following reasons; (1) they carry the information on the three-dimensional foot shape that cannot be represented by conventional measurements; and (2) the data is easily obtained and calculations are easily made with minimum expense.

Anthropometrical data of middle-aged Japanese women for industrial design applications.

Despite the growing importance of human interface design, and despite the growing number of working women, no considerations have been given to women's working spaces and tools. Their designs are based on men's anthropometrical data, and this does not assure safety and amenity of women's working environments. Moreover, few data on women's body measurements are available. The Research Institute of Human Engineering for Quality Life is carrying out an ergonomic anthropometrical study on a large number of Japanese people to create a database for industrial use. The fee for the use of these data is, however, making it very difficult to profit from their acquisition. Therefore, we conducted an anthropometrical study for industrial design use on middle-aged female subjects, who are in the most difficult age group to access. This report should be useful in designing working spaces and tools for women as laborers as well as users.

Malignant lymphoma of the lung: report of an autopsy case and review of literature.

A 74-year-old man complained of a cough and left chest pain. Chest X-ray showed marked pleural effusion and a large mass in the left lower lobe, and air bronchograms within the mass were observed by tomography and computed tomography (CT). About 3 months later, the patient died of left atelectasis and pneumonia. Autopsy revealed a localized tumor in the lower lobe of the left lung. Histologically, proliferation of lymphoma cells was noted. Immunoglobulin staining showed B cell-type monoclonality. No metastasis was evident except for a very small nodular area in the left renal cortex.

[Histo-pathology of the regenerating process in the tissue around the periodontally diseased teeth of beagle dogs. Clinical and histological analysis following flap surgery].

The regenerating process in tissue around periodontally diseased teeth (PDTs) and non-diseased teeth (NDTs) was studied with clinical and histological analysis following flap surgery. PDTs were prepared in the premolars of 7 beagle dogs by which surgically denuding the root surfaces by removing the alveolar bone. The denuded sites were covered with gutta-percha plates and gingival epithelial tissues and exposed to the oral environment for 4 weeks. Then flap surgery was performed on the PDTs. As control sites, the root surfaces of the NDTs were denuded by removing the alveolar bone at the time of flap surgery. The root surfaces of the PDTs and NDTs were planed with curette scalers at one root site but not at the other site. Clinical and histopathological findings were evaluated at fixed intervals for 32 weeks after surgery. Results of observation were as follows. 1. In the clinical evaluations, the gingival inflammation index, probing depth and attachment level were improved in the root planing (PR) group of both the PDTs and the NDTs, but in the non RP group of PDTs there was no improvement. 2. In the histologic observation, the position of the gingival margin, length of regenerated junctional epithelium, depth of gingival sulcus and the level of connective tissue attachment in the RP groups recovered in both the PDTs and the NDTs but not in the non RP groups.

[Histological study on gingival tissue reattachment after periodontal surgery. Effects of hydroxyapatite ceramic implantation to denuded dentin surfaces in rats].

The purpose of this study was to evaluate histological regeneration of epithelial and connective tissue attachment to the denuded dentin surface after hydroxyapatite ceramic granule (HAP) implantation. HAP (particle size 100-300 microns, burn temperature 900 degrees C) were implanted into dehiscent defects of alveolar bone which eliminated about a 1 x 1 mm area at mesial and palatal sites of the upper 1st molar in 20 male Wistar rats. Subsequently the root cementum was removed totally and dentin was denuded. Same osseous defects were formed but HAP was not implanted at any contralateral site for the purpose of control. Results of 8-week examination using light and electron microscopy were as follows: 1. In the HAP group junctional epithelium was regenerated on the denuded dentin surface 2 weeks after implantation and epithelial down growth was less than at the control site. 2. In the HAP group connective tissue reattachment with new cementum formation was observed at 2 to 4 weeks after implantation, the healing period tended to be shorter than at the control site and the connective tissue reattachment level was located more coronally. 3. In ultrastructural findings collagen fiber bundles attached to the denuded dentin surface had fibers continuing around HAP granules.