Combined irradiation and chemotherapy using ifosfamide, cisplatin, and etoposide for children with medulloblastoma/posterior fossa primitive neuroectodermal tumor--results of a pilot study

Ten children with newly diagnosed medulloblastoma/primitive neuroectodermal tumor of the posterior fossa were treated with total surgical resection, radiation therapy, and ICE chemotherapy regimen with ifosfamide (900 mg/m2, days 1-5), cisplatin (20 mg/m2, days 1-5), and etoposide (60 mg/m2, days 1-5) every 4 weeks for eight cycles. Four children under 2 years old were at first treated with eight cycles of ICE chemotherapy, and then irradiated. The ICE regimen was well tolerated by all children, with no irreversible adverse effects. However, dose reductions during the eight cycles were inevitable mainly due to myelosuppression. Complete remissions were achieved in eight of 10 patients at 1 month after completion of the treatment. One child showed recurrence 21 months after complete remission. The disease-free survival rate was 70% with a mean observation period of 24 months after surgery. The ICE regimen is a useful treatment modality for children with medulloblastoma. Further study is warranted to clarify long-term outcome in a number of patients.     

Isolation and analysis of age-related fluorescent substances in rat testes

Fluorescent substances were extracted from rat testicular tissue with 2,2-dimethoxypropane (DMP) and analyzed by 2-dimensional thin layer chromatography (TLC). One substance that accumulated with increasing age of the animals was isolated and analyzed quantitatively by spectrophotofluorometry using quinine sulfate as a standard. This substance, which was designated as an age-related fluorescent substance (ARFS), exhibited an excitation maximum at 355 nm and an emission maximum at 490 nm. Its fluorescence was quenched by metal chelators and at alkaline pH, indicating it contained a conjugated Schiff base structure. Quantitative analysis of this substance in the testes of rats 1, 2, 11 and 20 months of age showed that it increased linearly with age. The relation of this substance to aging also was indicated by its detection in animals of different ages fed diets of both low and high unsaturation.     

Absorption of nitrogen dioxide and nitric oxide by soda lime

Inhaled nitric oxide (NO) is used for the treatment of pulmonary hypertension as a selective pulmonary vasodilator. However, NO is oxidized rapidly to the more toxic nitrogen dioxide (NO2). Elimination of NO2 from inspired gas is essential for safe clinical use NO. We therefore investigated the efficacy of soda lime in absorbing NO2 from NO2-containing gases. Commercially available soda limes (Soda sorb and Wako lime-A), were exposed to the following six gas mixtures containing NO and NO2 in a hypoxic carrier gas for 20 min: No. 1: NO 40 ppm; No. 2: NO 35 ppm and NO2 5 ppm; No. 3: NO 30 ppm and NO2 10 ppm; No. 4: NO 20 ppm and NO2 20 ppm; No. 5: NO 10 ppm and NO2 30 ppm; and No. 6: NO2 40 ppm. Both types of soda lime completely absorbed the NO2 in all samples when it was present (Nos 2-6). NO concentration in these gas mixtures was reduced by an amount equal to the NO2 absorbed by soda lime. NO was absorbed minimally when NO2 was not present in the mixture. Nitrite was detected from the Wako lime-A granules exposed to the test gas by the chemical analysis. These findings suggest that soda lime completely absorbs NO2 by chemical neutralization, but NO is absorbed as simultaneously absorbed NO2 only where NO and NO2 coexist. Therefore, we conclude that soda lime is useful for NO2 absorption during NO inhalation therapy but NO monitoring from a point distal to the soda lime is required for precise control of inspired NO concentration.     

The 24-hour rhythms in plasma growth hormone, prolactin and thyroid stimulating hormone: effect of sleep deprivation

Twenty-four hour secretory rhythms of growth hormone (GH), prolactin (PRL) and thyroid stimulating hormone (TSH) were investigated in 9 normal adult men by means of serial blood sampling at 30 min intervals. The profiles of pituitary hormones were compared in 6 subjects between in normal nocturnal sleep condition and in delayed sleep condition. Plasma GH was measured with use of highly sensitive enzyme immunoassay (EIA) recently developed. Plasma TSH was also evaluated by highly sensitive time-resolved fluorometric immunoassay (TR-FIA). Time series analysis of plasma GH and PRL was performed by auto- and cross- correlation and spectral analysis. The detection limit of EIA for GH was 0.3 pg/ml and all plasma GH levels were within the detectable range of this EIA. Cross-correlation and spectral analysis suggested the presence of approximately 2-3 h rhythmicity of plasma GH. Plasma PRL appeared to have some 24-hour rhythmicity besides its sleep-dependent component. Sleep deprivation caused marked elevation of plasma TSH during night time. It is suggested that there appears two mechanisms regulating GH secretion: one has a sleep-independent and ultradian rhythm and another has a sleep-dependent rhythm.     

Survey bacterial isolates from blood samples during 1987-1993 in our department

We analyzed the changes in frequency of bacterial isolates from the blood samples in our department from May 1987 to December 1993. 565 isolates from 4887 samples (11.6%) were detected. Among the detected microorganisms, the rate of gram-positivecocci (GPC) was much higher than the other kinds of the isolates each year. Especially, 80-90% of GPC were occupied by only 2 kinds of microorganisms, coagulase negative Staphylococci (CNS) and S. aureus. Among gram-negative-rods (GNR), constant increase of S. marcescens and transient increase of Enterobacter and P. aeruginosa were recognized. In 30 cases (5.3%), 2-3 kinds of microorganisms were isolated concomitantly, and in 55 cases (9.7%), the microorganisms, which was mainly caused by CNS, S. aureus and Candida, was isolated from both blood samples and the tip of the IVH catheter concomitantly. 42.5% of the bacterial positive cases in 1933 underwent 2 more kinds of the indwelling catheters and 48.3% were administrated antibiotics. Most of the cases had underlying diseases including mainly malignant tumor (leukemia, solid tumor), cerebrovascular diseases, and multiple injuries.     

Epitopes of the target proteins of anti-SS-A/Ro and anti-SS-B/La autoantibodies

Anti-SS-A/Ro and anti-SS-B/La autoantibodies are diagnostically important in Sj?gren's syndrome and systemic lupus erythematosus. However, the relationship between generation of these autoantibodies and the pathogenesis of the diseases remains to be solved. Several lines of autoepitope mapping of the target molecules revealed that multiple epitopes on the molecules were recognized by sera from patients with the diseases. This indicates that these autoantigens themselves drive the autoimmunity, that is, the molecules specific autoreactive T cells are activated. Further studies to elucidate how the autoreactive T cells become activated would be of help in understanding the pathogenesis of the diseases.     

Protein C Osaka 10 with aberrant propeptide processing: loss of anticoagulant activity due to an amino acid substitution in the protein C precursor

We studied the molecular basis of protein C deficiency in a family with a history of thromboembolic disease. An approximately 50% reduction in anticoagulant activity despite normal levels of protein C amidolytic activity and antigen was detected in plasma from the proband. All the exons and intron/exon junctions of the protein C gene were studied using a strategy that combined polymerase chain reaction amplification with DNA sequencing of the amplified fragments. We identified a C-to-A change at nucleotide number 1387 of the protein C gene in the proband and his mother, and this mutant was designated protein C Osaka 10. The C-to-A change resulted in the substitution of Ser for Arg at position -1, which is the processing protease cleavage site. The mutant protein C was partially purified from plasma of the patient's mother using barium adsorption followed by ion-exchange column chromatography. It eluted at the same sodium chloride concentration as normal protein C, and thus gamma-carboxylation of the mutant protein appeared to be normal. The apparent molecular weight of this mutant protein C was the same as that of the normal protein on immunoblotting. Amino-terminal sequence analysis showed that the light chain of the mutant protein C had an additional Ser at position-1. Thus, the loss of anticoagulant activity of protein C Osaka 10 can be explained by alteration of the conformation of the Gla domain by the additional Ser in the mutant molecule.     

Continuous intra-arterial infusion therapy via the occiptial artery for head and neck tumors: second choice treatment

We report three cases in which continuous intra-arterial infusion therapy via the occipital artery was combined with radiotherapy for head and neck tumors. An angiographic catheter was inserted into the feeding artery of the tumor retrogradely via the occipital artery under fluoroscopic guidance. Patients treated were maxillary sinus cancer, tongue cancer and hemangiosarcoma. No complications occurred due to this procedure in any of the three patients. This procedure was considered very useful when the approach from the superficial temporal artery was not possible due to prior treatment.     

Localization and in vitro mutagenesis of the active site in the Saccharomyces cerevisiae mRNA capping enzyme

The yeast mRNA capping enzyme is composed of 52 (alpha) and 80 kDa (beta) polypeptides, which are responsible for its mRNA guanylyltransferase and RNA 5'-triphosphatase activities, respectively. We isolated the gene encoding the alpha subunit (CEG1) and showed that CEG1 is essential for yeast cell growth [Shibagaki et al., (1992) J. Biol. Chem. 267, 9521-9528]. In this study, CEG1 was expressed in Escherichia coli and the alpha subunit protein was purified to near homogeneity. A [32P]GMP-bound tryptic peptide derived from the recombinant enzyme-[32P]GMP covalent reaction intermediate was converted to a [32P]phosphoryl-peptide through periodate oxidation followed by beta-elimination. Hydrolysis of the [32P]phosphoryl-peptide with alkali resulted in [32P]N epsilon-phospholysine as the only phosphoamino acid, indicating that GMP in the enzyme-GMP complex is bound to a lysine residue via a phosphoamide linkage. Microsequencing of the [32P]GMP-peptide showed that the GMP binding site was located in the region between amino acids 60 and 75, which contained an internal trypsin-resistant lysine at position 70. CEG1 was subjected to site-directed mutagenesis and the mutant proteins were expressed in E. coli. Substitution of His or Ile for Lys70 entirely abolished the enzyme-GMP formation activity, and this mutation was lethal to yeast in vivo, supporting the notion that the active site in the alpha subunit is located at Lys70. Replacement of Lys70 with Arg reduced the ability to form the enzyme-GMP complex; however, yeast cells bearing this allele were not viable. A series of mutations, including 8 amino acid replacements and 3 insertions, near the active site (Lys70-Thr-Asp-Gly motif) were also introduced and the mutant polypeptides were examined for catalytic activity in vitro as well as yeast cell viability in vivo. There was a good correlation between the in vitro and in vivo functions of the mutant proteins, except when Asp72 was replaced with Glu, which allowed formation of the enzyme-GMP complex but failed to support cell growth. The results with Lys70 to Arg and Asp72 to Glu substitutions indicated that guanylyltransfer to RNA and/or additional roles besides cap formation per se are impaired in these mutant proteins.     

Mortality from major causes of death and its risk factors in the elderly--26-year follow-up study in Hisayama

The authors studied mortality from major causes of death and risk factors in the elderly in a long-term prospective survey conducted in a Japanese suburban community, Hisayama. In the baseline survey in 1961, we scrutinized 1658 residents of the town aged 40 years or older accounting for 92% of the total population in this age range. Of those, 591 residents (245 men and 346 women) aged 60 years or older, who were free from major cardiovascular disease, were selected for the present study. They were followed-up for 26 years from 1961 to 1987. The average age was 67 years for men and 70 years for women, being significantly higher for women than for men. During the follow-up period, 529 subjects (89.5%) died, and 448 were autopsied (autopsy rate 84.7%). The all-cause mortality (per 1,000 person-years) after adjustment for age was 89.9 for men and 56.7 for women, the former being significantly higher than the latter (p < 0.01). The age-adjusted mortality from cerebrovascular disease was estimated to be 21.4 for men and 9.9 for women, i.e. 8.9 and 8.8 from heart disease, and 19.9 and 10.6 from neoplasm, and 18.1 and 12.2 from-pneumonia, respectively. There was significant sex difference in mortality from cerebrovascular disease, neoplasm and pneumonia (p < 0.01) but not from heart disease (p > 0.1). Multiple Cox's proportional hazards regression analysis showed systolic blood pressure and male sex to be significant risk factors for death by cerebrovascular disease. Systolic blood pressure was also a predictor for death by heart disease.(ABSTRACT TRUNCATED AT 250 WORDS)