Fast Shadowing Algorithm for Linear Light Sources

This paper presents a fast shadowing algorithm for linear light sources that uses a ray-oriented buffer. Space segmentation by the buffer guarantees that if a point is included in a subspace, all light rays toward the point are also contained in the subspace. Each cell of the buffer stores a list of objects that lie within or intersect the subspace allocated to the cell. Therefore, candidate objects, those that may cast shadows onto a point, are determined by referring to the cell where the point is mapped. In addition, whether each candidate object actually casts shadows or not is tested with the bounding-volume of the shadow space to reduce the number of objects subjected to expensive light clipping. The bounding-volumes are also stored in the buffer. For efficiently generating the ray-oriented buffer, we present the cylindrical scan-conversion algorithm. The algorithm preconverts objects' surfaces to trapezia to decrease the light clipping cost, then connects the trapezia to the buffer cells. Due to the above improvements, our algorithm achieves over 10 times faster shadow generation compared to the conventional methods. Experimental results confirm that our method can generate realistic images with soft shadows in a few minutes.     

Genotype and phenotype of severe mitochondrial cardiomyopathy: a recipient of heart transplantation and the genetic control

Comprehensive analyses of mitochondrial (mt)DNA of a recipient of heart transplantation at age 7 because of severe cardiomyopathy revealed three germ line point mutations, each one in the 12S rRNA gene, in the CO1 gene and in the cytochrome b gene, respectively. As the somatic mutation, extensive fragmentation of mtDNA associated with 212 kinds of deletions was detected in contrast to 5 kinds in an age-matched negative control. A recipient's positive control having almost the same base-substitutions and mutations with the recipient except one in the CO1 gene also developed severe cardiomyopathy died at age 20. The close relation between phenotype and mtDNA genotype provides the basis of our understanding of cell death and premature ageing.     

Quantitative analyses for facial nerve MR imaging

It is clear, from our clinical experience, that the facial nerve in patients with facial palsy is enhanced on magnetic resonance (MR) imaging after intravenous administration of gadolinium diethylenetriamine. However, some problems with clinical reliability persist. There have been reports that normal facial nerves often show enhancement on MR imaging. We also question whether there are any differences in the degree of enhancement between Bell's palsy and Ramsay Hunt syndrome. To solve these problems, analyses were conducted using a personal computer by means of digital image-processing to measure the gray scale levels of enhanced facial nerves on MR imaging films. Seventeen cases of Bell's palsy, eight cases of Ramsay Hunt syndrome and fourteen normal subjects whose facial nerves showed enhancement on MR imaging were selected for the analyses. The concept of a facial nerve/whole image ratio (F/W ratio), analyzing the degree of enhancement of the facial nerve quantitatively, is introduced in this paper. The F/W ratio is the ratio of the gray scale level of the facial nerve region to the highest gray scale level in the skull at the MR imaging film. When the F/W ratios of these subjects were analyzed, no significant differences were found between Bell's Palsy and Ramsay Hunt syndrome in the degree of enhancement; facial palsy cases showed quantitatively larger F/W ratios than normal subjects.     

Isolation and structure determination of cassumunarins A,B, and C: New anti-inflammatory antioxidants from a tropical ginger,Zingiber cassumunar

New antioxidants, cassumunarins A, B, and C, were isolated from the rhizomes ofZingiber cassumunar, and the structures were determined by spectroscopic methods to be complex curcuminoids. The antixidant efficiency of cassumunarins was determined by inhibitory activity of autoxidation of linoleic acid in a buffer-ethanol system. The anti-inflammatory effect was measured by inhibition of edema formation on mouse ear induced by 12-O-tetradecanoylphorbol-13-acetate. Both types of activities were stronger for the cassumunarins than for the curcumin. Visiting scholar at University of Texas (October 1992–September 1993).     

Membrane targeting and binding of the 74-kDa form of mouse L-histidine decarboxylase via its carboxyl-terminal sequence

The role of the C-terminal region of the 74-kDa form of L-histidine decarboxylase (HDC) in the targeting to the endoplasmic reticulum (ER) was investigated in COS-7 cells. The deletion of a 10-kDa segment (residues 578-662) of the C-terminal end of HDC, especially a 20 amino acid sequence (residues 588-607), abrogated the targeting to the ER. The C-terminal 10-kDa portion is sufficient to target the green fluorescent protein (GFP) to the ER. The 74-kDa form of HDC synthesized in an in vitro translation system post-translationally associated with the heterogeneous canine microsomal membranes. These results suggest that the C-terminal 10-kDa portion of HDC contains a signal necessary for HDC to be targeted to the ER membrane.     

A case of advanced gastric cancer with liver and lung metastasis effectively treated by combined chemo-immunotherapy of MMC, 5'-DFUR, OK-432

A sixty-eight-year-old male patient was diagnosed as having inoperable advanced gastric cancer with liver and lung metastasis. The patient was treated by combined chemo-immunotherapy of MMC 10 mg/M, 5'-DFUR 800 mg/day and OK-432 5 KE/2 W. Six months after commencing chemotherapy, CT-scan and upper GI series revealed that metasized liver tumors and stomach lesion were remarkably decreased in size and no cancer cell was confirmed by endoscopic biopsy. Further, the metastatic lung tumor has disappeared on chest X-ray. The patient had been well without any evidence of tumor re-progression for over one year, but from July the liver tumor began to metastasize again and the patient eventually died of liver metastasis on Jan. 1, 1993.     

Effective treatment of mice with type II collagen induced arthritis with lethal irradiation and bone marrow transplantation

Ricin A-chain is delivered into macrophages via receptor-mediated endocytosis. We have found that following uptake via the mannose receptor, ricin A-chain is rapidly cleaved by endosomal proteases. Inhibition of endosomal proteases such as cathepsin D and B leads to the accumulation of toxin inside the cell. Inhibition of cathepsin D reduces ricin A-chain cytotoxicity, while blocking cathepsin B enhances cytotoxicity. Similar results were obtained using fibroblasts transfected with the mannose receptor. Our data strongly suggest that the activation or membrane translocation of ricin A-chain is dependent upon the action of specific proteases.