ENCEPHALOMYELONEURITIS WITH MEDIASTINAL GERM CELL TUMOR A Paraneoplastic Condition ?

An unusual case of encephalomyeloneuritis associated with germ cell tumor with mature and immature teratoma arising in the mediastinum is presented. There was an unusually long interval from the onset of neurologic symptoms to the development of malignancy. The histopathology, characterized by limbic encephalitis, brain stem encephalitis, cortical cerebellar degeneration and myeloneuritis, was similar to that of paraneoplastic encephalomyeloneuritis previously described in the literature. Virological and immunological studies failed to demonstrate any causative agents or autoantibodies reacting with brain tissue. The causal relationship between the malignant neoplasm and encephalomyeloneuritis thus seems to be very complex.     

Protective effects of a water-soluble extract from cultured medium of Ganoderma lucidum (Rei-shi) mycelia and Agaricus blazei murill against X-irradiation in B6C3F1 mice: Increased small intestinal crypt survival and prolongation of average time to animal death

Radioprotective effects of a water-soluble extracts from cultured medium of Ganoderma lucidum (Rei-shi) mycelia (designed as MAK) and Agaricus blazei (Agaricus) against the shortening of survival time or the injury of crypt by X-irradiation were investigated in male B6C3F1 mice. MAK and Agaricus at three different doses were mixed into basal diet into biscuits at 5, 2.5 and 1.25% and administered from 1 week before irradiation. MAK (5% group) significantly prolonged animal survival as compared with basal diet group (control group) after 7 Gy of X-ray irradiation at a dose rate of 2 Gy min(-1). At doses of 8, 10 and 12 Gy X-irradiation at a dose rate of 4 Gy min(-1) MAK (5% group) significantly increased crypt survival as compared to other groups. These results suggest that MAK can act as a radioprotective agent.     

Considering what clinical laboratories should become in the future--POCT, mail testing and OTC test

Medical staff working in laboratories have shown little or no interest in POCT, mail testing and OTC test. POCT and mail testing are laboratory systems that respectively involve a series of laboratory processes (advice on sampling, interpretation of data, referral to a doctor, etc.). However, the usefulness of data in the two systems differs. Data in POCT are directly used for medical treatment and those in mail testing are used as screening for health control or self-medication. OTC test is different from POCT and mail testing. People buy materials for OTC test at a drug store, then perform it and interpret the data by themselves. There are several factors in the development of POCT, mail testing and OTC test, for example the awareness of people about participation and responsibility for their own medical care, control of lifestyle-related diseases, relaxation of governmental regulation and development of technologies. These laboratories will grow gradually and influence clinical laboratories in medical facilities as well as commercial laboratories. Medical technologists and laboratory physicians should contribute to the sound development of these laboratories. As things are being changing so rapidly, medical technologists and laboratory physicians are forced to realign.     

Synthesis and side-chain crystallization of comb-like polymers obtained from isopropenyl-1,3,5-triazines carrying two,three, and four long alkyl groups

Monomers containing several octadecyl groups, e.g., 2-isopropenyl-4,6-bis(octadecylamino)-1,3,5-triazine ( 2 ), 2-dioctadecylamino-4-isopropenyl-6-octadecylamino-1,3,5-triazine ( 3 ) and 2,4-bis(dioctadecylamino)-6-isopropenly-1,3,5-triazine ( 4 ) were prepared by the alkylation reaction of 2,4-diamino-6-isopropenyl-1,3,5-triazine ( 1 ) with 1-bromooctadecane in the presence of sodium hydride. In the free-radical homopolymerization of these monomers, the polymer yield of 3 was lower than that of 2 due to a decrease in the ceiling temperature, and the polymerization of 4 did not proceed. Copolymerizations of these monomers with styrene or methyl methacrylate were carried out and the monomer reactivity ratios (r₁ and r₂) were determined. The monomer reactivity decreased with increasing the number of octadecyl groups in the monomers. Crystallinity of the octadecyl side chains in the resulting comb-like polymers was evaluated by differential scanning calorimetry.     

Long‐term observation of a Japanese mucolipidosis IV patient with a novel homozygous p.F313del variant of MCOLN1

Mucolipidosis type IV (MLIV) is an autosomal recessively inherited lysosomal storage disorder characterized by progressive psychomotor delay and retinal degeneration that is associated with biallelic variants in the MCOLN1 gene. The gene, which is expressed in late endosomes and lysosomes of various tissue cells, encodes the transient receptor potential channel mucolipin 1 consisting of six transmembrane domains. Here, we described 14‐year follow‐up observation of a 4‐year‐old Japanese male MLIV patient with a novel homozygous in‐frame deletion variant p.(F313del), which was identified by whole‐exome sequencing analysis. Neurological examination revealed progressive psychomotor delay, and atrophy of the corpus callosum and cerebellum was observed on brain magnetic resonance images. Ophthalmologically, corneal clouding has remained unchanged during the follow‐up period, whereas optic nerve pallor and retinal degenerative changes exhibited progressive disease courses. Light‐adapted electroretinography was non‐recordable. Transmission electron microscopy of granulocytes revealed characteristic concentric multiple lamellar structures and an electron‐dense inclusion in lysosomes. The in‐frame deletion variant was located within the second transmembrane domain, which is of putative functional importance for channel properties.     

Comparison of high-energy photon and electron dosimetry for various dosimetry protocols

The American Association of Physicists in Medicine Task Group 51 (TG-51) and the International Atomic Energy Agency (IAEA) published a new high-energy photon and electron dosimetry protocol, in 1999 and 2000, respectively. These protocols are based on the use of an ion chamber having an absorbed-dose to water calibration factor with a 60Co beam. These are different from the predecessors, the TG-21 and IAEA TRS-277 protocols, which require a 60Co exposure or air-kerma calibration factor. The purpose of this work is to present the dose comparison between various dosimetry protocols and the AAPM TG-51 protocol for clinical reference dosimetry of high-energy photon and electron beams. The absorbed-dose to water calculated according to the Japanese Association of Radiological Physics (JARP), International Atomic Energy Agency Technical Report Series No. 277 (IAEA TRS-277) and No. 398 (IAEA TRS-398) protocols is compared to that calculated using the TG-51 protocol. For various Farmer-type chambers in photon beams, TG-51 is found to predict 0.6-2.1% higher dose than JARP. Similarly, TG-51 is found to be higher by 0.7-1.7% than TRS-277. For electron beams TG-51 is higher than JARP by 1.5-3.8% and TRS-277 by 0.2-1.9%. The reasons for these differences are presented in terms of the cavity-gas calibration factor, Ngas, and a dose conversion factor, Fw, which converts the absorbed-dose to air in the chamber to the absorbed-dose to water. The ratio of cavity-gas calibration factors based on absorbed-dose to water calibration factors, N60Co(D,w), in TG-51 and cavity-gas calibration factors which are equivalent to absorbed-dose to air chamber factors, N(D,air), based on the IAEA TRS-381 protocol is 1.008 on average. However, the estimated uncertainty of the ratio between the two cavity-gas calibration factors is 0.9% (1 s.d.) and consequently, the observed difference of 0.8% is not significant. The absorbed-dose to water and exposure or air-kerma calibration factors are based on standards traceable to the National Institute of Standards and Technology (NIST). In contrast, the absorbed-dose to water determined with TRS-398 is in good agreement with TG-51 within about 0.5% for photon and electron beams.     

Spontaneous and osmium tetroxide-induced mutagenesis in an Escherichia coli strain deficient in both endonuclease III and endonuclease VIII

Thymine glycol, uracil glycol, 5-hydroxycytosine and 5-hydroxyuracil are common base lesions produced by cellular metabolism as well as ionizing radiation and environmental carcinogens. Escherichia coli DNA glycosylase, endonuclease III and endonuclease VIII recognize and remove these lesions from DNA. In this study, we assessed the mutagenic potential of these lesions in the supF gene as a forward mutation target in double-stranded plasmid DNA using an E.coli strain deficient in both endonuclease III and endonuclease VIII. These lesions were introduced into pTN89 DNA by the chemical oxidant osmium tetroxide. Spontaneous supF mutations occurred at a frequency of 3.03x10(-7) and osmium tetroxide-induced at a frequency of 8. 25x10(-7). Sequence analysis of supF mutants revealed that mutations occurred at cytosine sites rather than thymine sites, suggesting that thymine glycol is not the principal premutagenic lesion. In contrast, G:C-->A:T transitions were dominantly detected in the spontaneous and osmium tetroxide-induced mutations in the endonuclease III and endonuclease VIII double defective host. In this case, products of cytosine oxidation such as 5-hydroxycytosine, which are the substrate for endonuclease III and endonuclease VIII, were the principal mutagenic lesions.