Estimation of breakthrough time on activated carbon fixed bed adsorbers for multicomponent organic solvent vapors

The estimation of breakthrough time for multicomponent organic solvent vapors on activated carbon fixed beds is significantly complicated and difficult. This paper describes a simple estimation method of breakthrough time for the first component (foremost breakthrough component) in two- or three-component organic solvent vapors on an activated carbon fixed bed. The breakthrough time for the first component was expressed by the harmonic mean value of the breakthrough times in each pure component. Estimated breakthrough times were compared with the experimental ones.     

Myelinated fiber regeneration after crush injury is retarded in sciatic nerves of aging mice

To compare nerve regeneration in young adult and aging mice, the right sciatic nerves of 6- and 24-month-old mice were crushed at the sciatic notch. Two weeks later, both groups of mice were perfused with an aldehyde solution, and, after additional fixation, the sciatic nerves were processed so that the transverse sections of each nerve subsequently studied by light and electron microscopy included the entire posterior tibial fascicle 5 mm distal to the crush site. The same level was sectioned in unoperated contralateral nerves; these nerves served as controls. Electron micrographs and the Bioquant Image Analysis System IV were used to measure areas of posterior tibial fascicles and count the number of myelinated axons, the number of unmyelinated axons, and their frequency in Schwann cell units. In aging mice, the total number of regenerating myelinated axons was significantly reduced, but totals of regenerating unmyelinated axons in aging and young adults did not differ significantly. In aging mice, the frequency of Schwann cells that contained a single unmyelinated axon was greater, suggesting that before myelination began, Schwann cell ensheathment of axons also was slowed. After axotomy by a crush injury, the area of the posterior tibial fascicle was less than that in young adults and the distal disintegration of myelin sheath remnants also appeared to be retarded. The results indicate that responses of neurons, axons, and Schwann cells could be important in slowing the regeneration of myelinated fibers found in sciatic nerves from aging mice.     

Anti-allergic effect of bryonolic acid from Luffa cylindrica cell suspension cultures.

The anti-allergic activity of bryonolic acid (1) isolated from the cultured cells of Luffa cylindrica L. (Cucurbitaceae) was compared with that of glycyrrhetinic acid (2), the aglycone of glycyrrhizin from licorice. Compound 1, when administered to rats intraperitoneally at a dose of 600 mg/kg, inhibited homologous passive cutaneous anaphylaxis more strongly than 2 at the same dose. Compound 1 also significantly inhibited delayed hypersensitivity in mice which could not be inhibited by 2. In contrast to 2, 1 showed not only little toxicity but no visible side effects on mice, without impairing the activity of the hepatic enzyme (4,5 beta-dihydrocortisone:NADP+ delta 4-oxidoreductase) involved in steroid catabolism.     

Liver histopathology in clinical Reye syndrome

Analysis of the liver histopathology in 19 children with clinical Reye syndrome (RS) revealed that nine had diffuse panlobular steatosis, one giant cell hepatitis, one a mild choledochal cyst with inflammation, two multifocal spotty necrosis and one multiple centrilobular necrosis, the other five being normal. Four of the nine patients with diffuse panlobular steatosis showed microvesicular fatty droplets with central nuclei, which was consistent with findings characteristic for typical RS. Two cases showed a periportal area dominant macrovesicular fatty change, which was highly suggestive for metabolic disorder. In the other three cases, the findings were so variable in terms of the size of lipid droplets and the location of nuclei in hepatocytes that it was not possible to provide any clue for defining a diagnosis. These results confirmed the legitimacy of the diagnostic criteria of RS which included a liver biopsy as one of the mandatory conditions. They also indicated that RS-mimicking clinical pictures can be presented by miscellaneous conditions in which liver histology does not necessarily helpful in establishing definite diagnosis.     

Molecular cloning and expression of Mycobacterium tuberculosis strain Aoyama B peptide antigen genes in Escherichia coli--a gene encoding 15 kD antigen (AT 01)

A genomic library of Mycobacterium tuberculosis strain Aoyama B in Escherichia coli K-12 was constructed by cloning Sau 3A I cleaved M. tuberculosis Aoyama B chromosomal DNA into pUC18, pUC181 or pUC182. Clones reacting with anti-PPDs-rabbit-serum were screened by immunoblotting among 3 x 10(4) clones. Seven clones were selected; designating pAT 01, pAT 101, pAT 102, pAT 103, pAT 104, pAT 105 and pAT 201. On Western blotting, they were shown to produce 15 kD (pAT 01, pAT 101, pAT 105), 18 kD (pAT 103) and 60 kD (pAT 102, pAT 201) peptide antigens. Restriction endonuclease map of each of the above clones was composed, and putative coding frames of anti-PPDs-rabbit-serum reactive peptides were deduced by analysing deletion derivatives. Nucleotide sequence of pAT 01, encoding for 15 kD peptide antigen was analyzed, and a Hinf I-Hinf I fragment in pAT 01 was subcloned into pUC 18 lambda CPL 1 to determine the direction of its reading frame. The origin of promoter that drives cloned mycobacterial genes in E. coli was discussed.     

Ruptured pediatric posterior cerebral artery aneurysm 9 years after the onset of Kawasaki disease: a case report

CASE REPORT: A 12-year-old boy who had a history of Kawasaki disease 9 years ago experienced a subarachnoid hemorrhage by ruptured right posterior cerebral artery aneurysm. On day 1 operation, as the aneurysm was very fragile and bled easily, two intraoperative ruptures, including a very premature rupture, were encountered. As a result, a left hemiparesis especially severe in the left hand was caused by the right anterior thalamic infarction due to the occlusion of a thalamo-perforating artery arising near the neck of the aneurysm. DISCUSSION: The histopathological examination of the intraoperative excised aneurysmal dome disclosed the thickening of the endothelial inner due to the endothelial hypertrophy and the invasion of inflammatory cells. This finding of the aneurysm was partially mimicking the finding of the coronary artery of the patients with Kawasaki disease. The combination of cerebral aneurysm and Kawasaki disease has never been reported until now, and the etiology of the aneurysm of this patient is unclear.     

Influences of angiogenesis and lymphangiogenesis on cancerous invasion in experimentally induced tongue carcinoma

BACKGROUND: Although it is clear that dissemination via the blood system involves angiogenesis, it is uncertain whether tumors also induce lymphangiogenesis or simply invade existing peritumoral vessels. The purpose of this study was to elucidate changes in tumor blood and lymph vessels in cases involving the invasion of squamous cell carcinoma in the oral cavity, and its significance. Blood and lymph vessels densities in tongue carcinomas induced in hamsters were investigated. METHODS: Tongue cancer was induced by abrading the right margin of the tongue of each hamster with an endodontic barbed broach and subsequently applying 1.0% 9,10-dimenthl-1,2-benzanthracene (DMBA) dissolved in acetone, three times a week, at the same site. Fresh frozen sections were prepared and blood vessels stained blue by perfusion with Coomassie Brilliant Blue and lymph vessels stained brown for 5'-nucleotidase. The effects on the blood vessels and lymph vessels were observed. RESULTS: The results showed that blood and lymph vessel densities were greater in the advanced carcinoma tissues than in normal tissue. These were compared in terms of the mode of cancer invasion. As tumor invasion progressed, the blood vessel density decreased but lymph vessel density tended to be higher in high-degree tumor invasion than in low-degree tumor invasion. The expression of vascular endothelial growth factor-C was seen more frequently as tumor invasion progressed. CONCLUSIONS: The present findings indicated that angiogenesis and lymphangiogenesis are affected by cancerous invasion.     

Levels and ages of selenium and metals in sedimentary cores of Ise Bay as determined by 210-Pb dating technique

Bulletin of Environmental Contamination and Toxicology -     

Augmentation and subsequent attenuation of Ca2+ current due to lipid peroxidation of the membrane caused by t-butyl hydroperoxide in the rabbit sinoatrial node.

Cellular electrophysiological effects of membrane lipid peroxidation by t-butyl hydroperoxide (TBH) were studied in the rabbit sinoatrial (SA) node. Superfusion for 1-5 min with 300 microM TBH caused an initial increase and subsequent decrease in the spontaneous firing frequency of the SA node. Voltage clamp experiments revealed that TBH initially enhanced but later blocked the Ca2+ current. Thus, membrane lipid peroxidation appears to accelerate and then suppress physiological automaticity by causing biphasic changes in the Ca2+ current.     

Evidence by cellular mosaicism for monoclonal metastasis of spontaneous mouse mammary tumors

Female (SHN X C3H/He)F1 mice carrying spontaneous mammary tumors with cellular mosaicism with respect to isozymes of phosphoglycerate kinase (PGK) showed a high incidence of lung metastases. On resection of successively appearing mammary tumors, mice survived a maximum of 8 tumors. In these mice with multiple primary mammary tumors and multiple metastases, not only each individual metastasis but also all the metastases in the same lung had the same pattern of PGK isozymes and the same histologic type in the PGK-mosaic background of the host, indicating the monoclonal origin of these metastases. In several cases, this single pattern of metastatic colonies coincided with that of only one of several primary tumors, indicating that this tumor had metastasized. In these cases, these tumors were not necessarily the earliest of the primary tumors, and they were not located in any particular site.