Three-dimensional volume visualization of the in vivo human ocular lens showing localization of the cataract

An in vivo human lens containing a cataract has been visualized by volume rendering a transformed series of 60 rotated Scheimpflug digital images. The data set was obtained by rotating the Scheimpflug camera about the optic axis of the lens in 3-degree increments. The set of 60 Scheimpflug digital images were mathematically transformed into a new data set in which the images are oriented perpendicular to the optic axis of the eye. The transformed set of optical sections were first aligned to correct for eye movements during the data collection process, then rendered into a three-dimensional volume reconstruction with volume-rendering computer graphics techniques. The viewpoint and the transparency of the volume rendered in vivo human lens were varied in order to observe volume opacities in various regions of the lens. To help visualize lens opacities, the intensity of light scattering was pseudocolor-coded as an integral part of the three-dimensional volume rendering. Three-dimensional, pseudocolored volume rendering of the in vivo human ocular lens represents a new technique to visualize in vivo human cataracts.

Inhibition of steroid-induced cataract in rat eyes by administration of vitamin-E ophthalmic solution

The efficacy of a vitamin-E (VE) ophthalmic solution was evaluated on a newly developed rat steroid-induced cataract model. Brown Norway rats irradiated with 2 Gy X-ray, right eyes only, were divided into 5 groups: the control group; 2 steroid (1 mg/kg/day)-treated groups with topic (Top) and systemic (Sys) administration, and 2 VE-treated groups, 1 with the same treatment as the Top group with the addition of 5% VE twice a day (Top + VE) and 1 with the same treatment as the Sys group with 5% VE twice a day (SYS + VE). The lens changes were documented with a Scheimpflug camera and changes in light scattering were evaluated quantitatively. The VE-treated groups (Top + VE and Sys + VE) showed a significant inhibition of the increase in the opaque area compared with each of the non-VE-treated groups. The VE ophthalmic solution was strong enough to prevent steroid-induced cataract in rats.

Proto-oncogene products Vav and c-Cbl are involved in the signal transduction through Grb2/Ash in hematopoietic cells

Grb2/Ash is composed of one SH2 and two SH3 domains and functions as an adapter linking tyrosine kinase receptors and Ras in fibroblasts. We have investigated the nature of proteins interacting with Grb2/Ash in hematopoietic cells. The product of the vav proto-oncogene (Vav) is expressed exclusively in hematopoietic cells and has guanine nucleotide exchange activity. Here we report that granulocyte/macrophage-colony- stimulating factor (GM-CSF), interleukin-3, and erythropoietin (Epo) induce rapid and transient tyrosine phosphorylation of Vav and that Vav is constitutively associated with the SH3 domain of Grb2/Ash in a human leukemia cell line UT-7. These data implicate Vav in a signaling pathway leading to activation of Ras or Ras-related proteins in hematopoietic cells. Furthermore, we have shown that the proto-oncogene c-cbl product (c-Cbl) is also tyrosine-phosphorylated by stimulation with GM-CSF or Epo and is constitutively associated with the SH3 domain of Grb2/Ash in UT-7. However, we could not find the homologous regions with guanine nucleotide exchange factors or GTPase-activating proteins in the c-cbl gene. Therefore, Grb2/Ash might also transduce a signal that is different from the signal leading to the small-G protein regulation.

[Study of serum CDDP concentrations in patients with advanced or recurrent adeno-or squamous cell carcinoma under combination chemotherapy of 5-FU (CIV) and low-dose CDDP (IV)]

The combination chemotherapy of 5-FU (CIV) and low-dose CDDP (IV) was applied to 15 patients with advanced or recurrent adeno-or squamous cell carcinoma. Schedules for treatment were as follows: A: 5FU 320 mg/m2/day for 28 days with 7 mg CDDP/m2/day for 5 days/weekx4. B: 5FU 320 mg/m2/day for 28 days with 3.5 mg CDDP/m2/day for 5 days/weekx4, C: after B, 7 mg CDDP/m2/day/every 3 or 4 days. Serum CDDP concentrations were measured by flameless atomic absorption spectrophotometry. In all patients, a tendency to accumulation of total CDDP was observed. No severe side effects (> or = grade 3) were observed in patients given B therapy. We previously reported that there was no significant difference between A and B therapy in anti-tumor effects. The peak total CDDP concentrations were 1000 or more than 1000 ng/ml in A therapy, and 500 to 1000 ng/ml in B (with the exception of a case) therapy. These results demonstrated that B therapy could maintain the anti-tumor effect and decrease the severity and frequency of side effects, suggesting that the optimal serum concentration of total CDDP might be between 500 and 1000 ng/ml.

[Annual daily intakes of Hg, PCB and arsenic from fish and shellfish and comparative survey of their residue levels in fish by body weight]

We have been surveying toxic substances in food and foodstuffs and carrying out a total diet study on the intakes of various substances since 1979 in cooperation with local public institutes in Japan. In this paper, we report the daily intakes of mercury, PCB and arsenic from foods, and the relation between the concentrations of these substance in fish and the fish body weight. The intakes of mercury and arsenic were 6.9-11.0 micrograms/ man/day and 120-230 micrograms/man/day, respectively. The intakes of these substances remained on a stable level from 1979 to 1994. On the other hand, the intake of PCB decreased from 3.1 micrograms/man/day in 1979 to 0.9 microgram/man/day in 1994. Most of the intakes of mercury, PCB and arsenic were derived from the diet group "fish and shellfish". The level of mercury in fish increased with increasing fish body weight. For PCB and arsenic, there was no correlation between these concentrations in fish and the fish body weight, except that mackerel and croaker show a higher concentration of PCB when they are small. Arsenic shows almost a constant level in each fish regardless of their body weight.

Evaluation of transparency and barrier function of the cornea by Scheimpflug images

Two new methods of corneal analysis with Scheimpflug images will be introduced in this paper. The first study was to document the light scattering of the cornea itself using a newly modified Scheimpflug camera with higher magnification. Details of the slit images of the cornea could be evaluated more precisely than those of images taken with an existing camera. The second study was to evaluate the corneal epithelial barrier function by measuring the intensity of the light scattering originating from instilled fluorescein excited through filters. Fluorescein accumulation in the damaged epithelium and diffusion with time into the stromal tissue could be observed in two-dimensional images and the changes could also be documented by measuring the intensity and extent of light scattering. These newly developed methods will be useful for studies of the cornea.

Ultrastructural localization of the intercellular adhesion molecule (ICAM-1) on the cell surface of high endothelial venules in lymph nodes

BACKGROUND

The high endothelial venules (HEV) in the lymph nodes are essential for lymphocyte recirculation. As a first step, the HEV surface interacts with lymphocytes through adhesion molecules. It is important to know where adhesion molecules are expressed on the surface ultrastructure and how these structures interact with lymphocytes.

METHODS

To demonstrate the ultrastructural mechanism of interaction between the HEV surface and lymphocytes through the intercellular adhesion molecule (ICAM-1), rat mesenteric lymph nodes were perfused through the superior mesenteric artery with the primary antibody (antirat ICAM-1 antibody) and secondary antibody (antimouse IgG coupled to 15 nm gold particles), which were diluted with hypothermic University of Wisconsin (UW) solution. After the immunoreaction, we analyzed the HEV three-dimensionally and quantitatively using immunoscanning electron microscopy (ISEM) combined with transmission electron microscopy (TEM).

RESULTS

HEV expressed ICAM-1 in a 5-30-fold higher concentration than other vessels. Its distribution was extensive over the luminal surface of the cell down to the junctional area. The endothelial surface of HEV undulated to form branched microfolds, along which ICAM-1 was expressed. Cytoplasmic processes of lymphocytes were seen in microfurrows between microfolds and adhered to the sides of the folds.

CONCLUSIONS

These observations imply that the microfolds expressing ICAM-1 and microfurrows are specific ultrastructural features for trapping lymphocytes, thus initiating lymphocyte emigration into the lymph node parenchyma.

Role of high-affinity folate-binding protein in the plasma distribution of tetrahydrofolate in pigs

Stability and protein-binding properties of tetrahydrofolate (THF) in pig plasma were studied in vitro. THF in plasma was stable for more than 120 min when it existed in a bound form, whereas THF both in plasma ultrafiltrate and in plasma ultrafiltrate plus porcine albumin was degraded rapidly and disappeared soon after its addition. These results suggest that high-affinity folate-binding protein (HFBP) is related to the stability of THF. THF-protein binding kinetic analysis showed that porcine plasma had HFBP and low-affinity binding protein (albumin) for THF. Dissociation constant and maximal binding capacity of HFBP were calculated to be 0.4 and 70 nM, respectively, indicating that > 98% of endogenous plasma THF existed in bound form with HFBP. Porcine albumin was not essentially a protein that binds and protects endogenous THF from degradation. We conclude that most endogenous THF binds to HFBP and only the unbound form of THF is rapidly degraded in pig plasma. HFBP protects THF from degradation and allows THF to exist stably in pig plasma. In addition, HFBP may govern the species specificity of plasma folate distribution in pigs.

Crystallization of synthetic Escherichia coli-type lipid A

Synthetic Escherichia coli-type lipid A formed hexagonal plate crystals when it was precipitated by the addition of 2 volumes of 95% ethanol containing 375 mM MgCl2 and incubated in 70% ethanol containing 250 mM MgCl2 at 4 C for 10 days. Analyses of crystals by electron diffraction and synchrotron X-ray diffraction showed that crystals consist of hexagonal lattices with the lattice constant (a side of the lozenge as a unit cell on the basal plane) of 4.62 angstrom and the longitudinal axis (perpendicular to the basal plane) of 49.3 +/- 1.3 angstrom. Results suggest that the previous finding that various kinds of R-form lipopolysaccharides crystallized but free lipid A isolated by acid hydrolysis from Re lipopolysaccharide did not crystallize under the same experimental conditions (Kato et al, J. Bacteriol., 172:1516-1528, 1990) is due to structural changes of lipid A occurring during the procedure of isolation of free lipid A.

Glycolipid acceptor specificity of a human Gal beta(1-3/1-4) GlcNAc alpha 2,3-sialyltransferase

A human Gal beta(1-3/1-4)GlcNAc alpha 2,3-sialyltransferase, called ST-4, is a sialyltransferase involved in the in vivo biosynthesis of sialyl Lewis X (NeuNAc alpha 2-3Gal beta 1-4(Fuc alpha 1-3)GlcNAc) determinant. The ST-4 enzyme could utilize nLc4Cer (Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1'Cer) containing type 2 sugar chain, Lc4Cer (Gal beta 1-3GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1'Cer) containing type 1 sugar chain, Gg4Cer (Gal beta 1-3GalNAc beta 1-3Gal beta 1-4Glc beta 1-1'Cer), and LacCer as glycolipid acceptor substrates, but not other neutral glycolipids (GalCer, GlcCer, Gb3Cer, Gg3Cer, Gb4Cer) and gangliosides (GM1a, GM2, GM3, GD1a, GD1b, and GT1b) as substrates. The order of sialic acid incorporation into glycolipids for the enzyme was nLc4Cer > Gg4Cer > Lc4Cer > LacCer. The apparent Km values of ST-4 for nLc4Cer and Gg4Cer were 0.47 and 2.5 mM, respectively. Thus, the ST-4 could efficiently utilize both nLc4Cer and Gg4Cer as glycolipid acceptor substrates in vitro, suggesting that the substrate specificity of the enzyme may be similar to that of a glycolipid sialyltransferase (SAT-3), which is defined as the enzyme that uses both nLc4Cer and Gg4Cer as glycolipid acceptor substrates.

Epidemiologic characteristics of rhegmatogenous retinal detachment in Kumamoto, Japan

BACKGROUND

The epidemiology of rhegmatogenous retinal detachment in Asians is not well known. We studied the epidemiologic characteristics of rhegmatogenous retinal detachment in Kumamoto, Japan.

METHODS

The study was based on a retrospective chart review of hospital patients who were treated for primary rhegmatogenous retinal detachment in 1990. The data were collected from seven hospitals in the Kumamoto area.

RESULTS

From a population of 1 840 000, 192 residents developed retinal detachment. The annual incidence was therefore 10.4 per 100 000 population (9.6 for males, 11.2 for females). The incidences of three types of detachment-nontraumatic phakic, aphakic, and blunt trauma--were 9.8, 0.5 and 0.2 per 100 000 population, respectively. In 109 of 180 patients (60.6%) with nontraumatic phakic detachment, retinal breaks were associated with lattice degeneration. In females, 14 of 106 nontraumatic phakic cases (13.2%) were secondary to macular holes.

CONCLUSION

Compared with previously published studies from other countries, the incidence of detachments associated with lattice degeneration and macular hole was higher, while the incidences of aphakic detachment and detachment due to blunt trauma were lower in Japan. Racial factors and living habits may affect the development of retinal detachment.

Actions of acidic fibroblast growth factor fragments on food intake in rats

Acidic fibroblast growth factor (aFGF) has suppressive effects on food intake. In the present study, the effect of aFGF fragments on food intake were investigated in rats. Infusion of a carboxyl-terminal fragment of aFGF, aFGF-(114-140), did not affect food intake, whereas an amino-terminal fragment of aFGF, aFGF-(1-15), was significantly inhibitory. Other amino-terminal fragments, aFGF-(1-20), aFGF-(1-29) and aFGF-(9-29), did not affect food intake. However, [Ala16]aFGF-(1-29) and [Ser16]aFGF-(1-29) in which the cysteine residue at position 16 was replaced with alanine and serine, respectively, had significant suppressive effects on food intake. Infusion of a functional antagonist for FGF receptor, anti-FGFR-1 antibody, into the lateral hypothalamus (LHA) significantly increased food intake. The results suggest that: the amino-terminal portion of aFGF is active in food intake suppression; the replacement of cysteine residue by alanine or serine is important in some amino-terminal aFGF fragments; and the LHA is involved in feeding suppression actions by aFGF and some fragments.

Somatoform pain disorder in a case of Klinefelter's syndrome with multiply operated lower back

We report a case of Klinefelter's syndrome with multiply operated low back (MOB). Psychological and/or psychosocial problems related to MOB have been of recent interest in the field of orthopedic surgery. Based on psychiatric interviews, this case was diagnosed as a somatoform pain disorder of the DSM-III-R somatoform disorders. In addition to psychological problems, the pain was partly explicable by severe osteoporosis, which was prematurely caused by endocrinological disturbances associated with Klinefelter's syndrome. Patients with this syndrome are more likely to develop severe osteoporosis. In the presenile period of Klinefelter's syndrome with severe osteoporosis, liaison psychiatrists may pay attention to somatoform disorders (e.g. somatoform pain disorder and conversion disorder) linked with the MO.

The ultrastructure of intravascular and coelomic scavenger macrophages of the mouse embryo

The aim of this study was to establish whether or not mononuclear cells which appear in both the vitelline vessels and embryonic coelom in mice prior to liver hemopoiesis are specialized scavengers. Before the initiation of liver hemopoiesis, the majority of the embryonic blood cells were primitive erythroblasts derived from yolk sac hemopoietic foci. In addition, the peripheral blood contained a few free phagocytes as early as 10 days of gestation. The phagocytes devoured various cell elements such as degenerating erythroblasts and cell fragments. Ultrastructurally, they had long filamentous cytoplasmic projections on their cell surface, clear subsurface vacuoles or vesicles, lipid droplets, a few lysosomal granules, large heterogeneous phagolysosomes and residual bodies. Mononuclear phagocytes with ultrastructural features similar to those of the intravascular phagocytes also could be observed in the intraembryonic peritoneal cavities at 10 days of gestation; they sometimes engulfed possible mesothelial cells undergoing degeneration. Based on fine structural criteria, these intravascular and coelomic phagocytes were considered to be specialized scavenger macrophages with the function of clearing the blood and tissue fluid of whatever has been ingested. In so doing, they serve as the most primitive discriminating filter set in embryonic circulation.

c-Cbl is inducibly tyrosine-phosphorylated by epidermal growth factor stimulation in fibroblasts, and constitutively tyrosine-phosphorylated and associated with v-Src in v-src-transformed fibroblasts

The c-cbl gene was cloned as the cellular homolog of the v-cbl oncogene that is the transforming component of a murine tumorigenic retrovirus, CAS NS-1, though the biological roles of c-Cbl remain to be elucidated. We have previously reported that c-Cbl is implicated in the signal transduction triggered by granulocyte-macrophage colony-stimulating factor or erythropoietin in hematopoietic cells. Here, we observed tyrosine phosphorylation of C-cbl in cells expressing epidermal growth factor receptor depending on EGF stimulation and in v-src transformed cells. Furthermore, c-Cbl was revealed to associate with v-Src in vivo. By means of binding experiments using glutathione S-transferase fusion proteins, we have found that the SH2 and SH3 domains of many proteins bind to c-Cbl. These findings strongly suggest that c-Cbl is implicated in a wide variety of signal transduction pathways, including those of EGF receptor and Src protein, as well as in the signaling pathways of hematopoietic cells.

TPO/c-mpl ligand induces tyrosine phosphorylation of multiple cellular proteins including proto-oncogene products, Vav and c-Cbl, and Ras signaling molecules

Thrombopoietin (TPO)/c-mpl ligand is a hematopoietic growth factor that stimulates proliferation and maturation of megakaryocytes. To analyze the signaling pathway downstream of the c-mpl product, we used a human megakaryoblastic cell line, Mo7e, that has been proved to be responsive to TPO in terms of DNA synthesis. In this study, we found that TPO treatment resulted in tyrosine phosphorylation of Jak-2 kinase. Moreover, it was revealed that several functional molecules involved in the Ras signaling pathway, Shc and Sos, were phosphorylated by treatment with TPO. Finally, tyrosine phosphorylation of the proto-oncogene products, Vav and c-Cbl, has been proved to be induced by TPO. These results suggest that TPO could activate several signaling pathways including the Jak/Stat pathway, the Ras pathway and possibly another pathway involving the c-Cbl proto-oncogene product.

Dimethylsulfoxide potentiates the suppressive effects of lidocaine on synaptic transmission in bullfrog sympathetic ganglion

The effects of dimethylsulfoxide used as a solvent on the suppressive effects of lidocaine on synaptic transmission were examined in the bullfrog sympathetic ganglion. Compound action potentials (CAP) in response to orthodromic stimulation of the presynaptic nerve trunk were recorded extracellularly from the bullfrog sympathetic ganglion. Application of lidocaine dissolved in normal Ringer's solution significantly decreased the amplitude of CAP. This suppressive effect of lidocaine was markedly potentiated when lidocaine was dissolved in 0.1% DMSO solution. A similar potentiating effect of DMSO was observed on the suppressive action of lidocaine on acetylcholine (ACh)-induced depolarizing response recorded intracellularly from the sympathetic ganglion cell. On the other hand, 0.1% DMSO solution alone had no effect on synaptic transmission, resting membrane potential, resting membrane resistance or ACh receptor activity. The present findings suggest that DMSO as solvent should be used carefully because of its potentiating effect on drug actions. Since the effect of lidocaine is due to the suppression of nicotinic ACh receptor at the postsynaptic membrane, DMSO may allosterically act on the nicotinic ACh receptor causing an increase in efficacy of lidocaine.

Circadian rhythm and variability of heart rate in Duchenne-type progressive muscular dystrophy

Using 24-hour Holter monitoring and time domain and power spectral measurements, we evaluated the variability of the heart rate and its circadian rhythm in 55 male patients with Duchenne-type progressive muscular dystrophy (DMD) to characterize their autonomic function versus findings in 20 normal controls. Comparisons were also made in patients with mild, moderate, and severe stages of DMD. The percent difference between successive RR intervals that exceeded 50 ms, a measure of parasympathetic tone, was significantly lower even in patients with early stage of DMD than in controls (p < 0.01). This trend became marked with disease progression. Power in the high-frequency (HF) range (0.15 to 0.40 Hz), a measure of parasympathetic tone, was lower (p < 0.01), and the ratio of the power in the low-frequency (LF) range (0.04 to 0.15 Hz) and that of HF range (LF/HF ratio), a measure of sympathetic tone, was higher in DMD patients versus controls (p < 0.01). This trend was also marked with disease progression. Patients with mild or moderate disease had a slight circadian alteration in HF and LF/HF ratio. Patients with severe disease had virtually no circadian rhythm in HF. Their LF/HF ratio was higher at night (p < 0.01), lower in the morning (p < 0.01), and still lower during the day (p < 0.01), the opposite of control findings. The autonomic abnormalities in DMD were thus characterized by a significant increase in sympathetic activity and a significant decrease in parasympathetic activity. Thus, heart rate variability and circadian rhythm were useful in assessing autonomic dysfunction in DMD.

Alveolar rhabdomyosarcoma of the lung in a child

The case of a 22-month-old boy with alveolar rhabdomyosarcoma of the lung is presented. Brain metastasis and recurrence of the right pulmonary hilum and parietal pleura developed 6, 11, and 24 months (respectively) after tumor resection. Chemotherapy and radiotherapy were effective. Neuron-specific enolase was very helpful in detecting metastasis and disease recurrence. Primary pulmonary rhabdomyosarcoma can be divided into two groups: tumor in the normal lung, and tumor in cystic lesions of the lung.

Cortical field potentials preceding vocalization and influences of cerebellar hemispherectomy upon them in monkeys

Field potentials preceding vocalization were recorded with electrodes chronically implanted on the surface and at 2.0-3.0 mm depth in various cortical areas in three monkeys. Surface-negative, depth-positive (s-N, d-P) slow potentials prior to vocalization were recorded in the premotor (including the Broca's homology), motor and somatosensory cortices in both hemispheres, and the supplementary motor area in the cerebral hemisphere. Such premovement potentials were recorded also in the cingulate and prefrontal cortices when a monkey uttered with intense motivation for reward. Cerebellar hemispherectomy on the right side eliminated the s-N, d-P premovement potentials in the motor cortex and in the posterior bank of inferior limb of the arcuate sulcus (homolog of Broca's area) in the left hemisphere. Vocal tone contained less components in different frequencies, and its duration became more variable than before the operation. These facts suggest that the neocortical area homologous to the human speech area takes part in generation and control of monkey vocalization together with the cerebellum, possibly through cerebro-cerebellar interactions, against ideas so far offered on nonhuman primate vocalization.

A fluorescence in situ hybridization (FISH) analysis with centromere-specific DNA probes of chromosomes 3 and 17 in pleomorphic adenomas and adenoid cystic carcinomas

Aberrations of chromosomes 3 and 17 were studied by FISH using centromere-specific DNA probes in 11 salivary adenoid cystic carcinomas (ACC) and 8 salivary pleomorphic adenomas (PA), with 3 lymph nodes as controls. Two hybridized signals were detected in 92.8 +/- 2.7% of controls, 73.2 +/- 7.0% of PA and 66.8 +/- 7.9% of ACC cells for chromosome 3, and in 90.4 +/- 2.3% of controls, 59.5 +/- 25.0% of PA and 44.8 +/- 20.2% of ACC for chromosome 17. More than 3 hybridized signals, which indicate polysomy, were observed in 3.1% of controls, 15.5% of PA and 22.9% of ACC cells for chromosome 3, and in 1.2% of controls, 10.3% of PA and 23.1% of ACC cells for chromosome 17. A single hybridized signal was much more frequent for chromosome 17 than for chromosome 3. These findings suggest that polysomy of both chromosomes occurs during the development of salivary gland tumors, and its frequency is increased in adenoid cystic carcinoma as compared to pleomorphic adenoma. In addition, monosomy of chromosome 17 could possibly be significant in salivary gland tumors.

Monosomy of chromosome 18 detected by fluorescence in situ hybridization in colorectal tumors

BACKGROUND

At least two different evolutional pathways of colorectal cancer, namely the adenoma-carcinoma sequence and de novo carcinogenesis, have been indicated. However, whether there is a difference between them in affected chromosomes and genes has not yet been elucidated. Chromosomal examination is expected to provide a clue to an answer to this question. In this study, the relation of aberrations in chromosome 18 to type of colorectal cancer was examined.

METHODS

Numeric aberrations in chromosome 18 were investigated in 71 colorectal tumors by means of fluorescence in situ hybridization, using an alphoid satellite DNA probe specific for the pericentromeric region on chromosome 18.

RESULTS

The loss of one chromosome 18 was found in 33% (6 of 18) of patients with early cancer, excluding those with cancer in an adenoma. The loss was frequent in early colorectal carcinomas without foci of adenoma (four of six patients, 67%), whereas monosomy 18 was not significant in those with foci of adenoma except for patients with a hereditary background. Specimens exhibiting monosomy 18 were macroscopically classified as flat lesions, but the converse was not true. No adenoma showed monosomy 18. It was encountered in 44% of nine cancers with invasion to the muscularis propria. However, no significant subpopulation of monosomy 18 was present in cancers penetrating through the serosa or adventitia in which polysomic populations were often identified alternatively. Furthermore, tetrasomy for this chromosome was exclusive in these advanced cancers.

CONCLUSIONS

The loss of chromosome 18 is closely related to colorectal cancers without foci of adenoma.

Association between the interarch distance and food bolus size in the early phase of mastication

The effects of food bolus size on interarch distance were examined in three dimensions with sphere-shaped gelatin (5 to 25 mm diameters). Interarch distance in the early phases of chewing indicated a significant linear relation (p < 0.001) to food bolus size. The correlation coefficients were high particularly at the second and third opening sequences. At the first opening sequence during ingestion, interarch distance for small bolus of less than 15 mm was nearly constant and relatively wider than the bolus size. Practical information for determining the interincisal distance in prosthodontic treatment is provided.