Toluene concentrations in 9 brain regions of acutely exposed rats and that in 11 brain regions of a human case who inhaled toluene prior to death are described. After exposure to toluene by inhalation (2000 or 10,000 ppm) for 0.5 h or by oral dosing (400 mg/kg), rats were killed by decapitation 0.5 and 4 h after onset of inhalation and 2 and 10 h after oral ingestion. After each experimental condition the highest range of brain region/blood toluene concentration ratio (BBCR) was in the brain stem regions (2.85-3.22) such as the pons and medulla oblongata, the middle range (1.77-2.12) in the midbrain, thalamus, caudate-putamen, hypothalamus and cerebellum, and the lowest range (1.22-1.64) in the hippocampus and cerebral cortex. These distribution patterns were quite constant. Toluene concentration in various brain regions were unevenly distributed and directly related blood levels. In a human case who had inhaled toluene vapor, the distribution among brain regions was relatively similar to that in rats, the highest concentration ratios being in the corpus callosum (BBCR: 2.66) and the lowest in the hippocampus (BBCR: 1.47).

No abstract

This report describes a slight difference in the rate of decrease of serum paraquat and diquat concentrations in eight human cases of poisoning by the herbicide PreegloxL (containing paraquatCl2, 5% and diquatBr2, 7%) and the distribution of each in three autopsied cases. There was no variation between the serum concentrations of paraquat and diquat within 24 h after ingestion, but paraquat remained at a slightly higher concentration than diquat after more than 24 h. The decrease of urinary paraquat and diquat concentrations was almost the same during the 24-h determination period. In three autopsied cases, diquat concentrations in the tissues were relatively lower than those of paraquat, except in bile. Paraquat and diquat were unevenly distributed in various tissues and fluids, but the distribution patterns of each in any particular tissues were quite similar. As no difference was observed in the decrease of urinary paraquat and diquat, the much higher concentration of diquat in bile indicates that bile may be one of the effective factors in lowering the concentration of diquat in serum and in tissues of the human body long after ingestion.

A rapid, simple method based on second-derivative spectroscopy of the simultaneous analysis of paraquat and diquat in serum and urine is described. Paraquat and diquat in serum were deproteinized with sulfosalicylic acid, and those in urine were reduced with NaOH-dithionite solution. A qualitative and quantitative analysis of reduced paraquat and diquat was made at the amplitude peaks of 396-403 nm and 454-464 nm in the second-derivative spectra, respectively. The entire procedure was completed within about 10 minutes for a serum sample and within about 5 minutes for a urine sample. Application of the proposed method on a poisoned patient is also reported.

The copper and iron status in the liver of non-tumor bearing Long-Evans Cinnamon (LEC) rats (average age 17 months) was investigated. A direct quantitation of loosely-bound copper and iron was also investigated by using a chelating agent, nitrilotriacetic acid (NTA-chelatable free copper and iron). Besides the total copper and iron contents, the level of NTA-chelatable free copper was also higher in LEC rats than in LEA rats (P<0.05). But for the free iron level there was no significant difference between the two rat groups (P>0.05). The formation of thiobarbituric acid-reactive substances was higher in LEC rats than in LEA rats (P<0.01). The 4-hydroxy-2-nonenal (HNE)-modified proteins were also clearly demonstrated in LEC rat liver. The copper and iron which produced the most important effect in the process of oxidative damage in LEC rats could not be distinguished. Even though free copper, which could induce free radical injuries, was increased in LEC rats, neither tumor-induction nor preneoplastic lesions in the experimental LEC rats were observed. Therefore it is speculated that the elevation of a free iron is another important factor. Copper and iron, both important transition metals in the body, may participate in the induction of DNA damage and oncogenesis.

No abstract

A 62-year-old man with myelodysplastic syndrome (MDS) presented to our hospital with a high fever. Although treatment with broad-spectrum antibiotics was initiated, his respiratory status worsened to the point that he required mechanical ventilation. However, he was successfully treated with a corticosteroid without immunosuppression. Sequential transbronchial lung biopsies revealed abundant fibrin exudate in the alveolar spaces, which was subsequently replaced by fibroblasts, showing that acute fibrinous and organizing pneumonia (AFOP) gradually changes into organizing pneumonia. Our case demonstrated both the efficacy of corticosteroid-monotherapy and the histological course of AFOP.

ObjectiveTo investigate the relationship between the precursors of high grade serous ovarian cancer (HGSOC) and the characteristics of patients with a low HGSOC risk in terms of the effects of pregnancy.MethodsWe prospectively examined consecutive cases in which the bilateral fallopian tubes were removed during benign gynecological or obstetric surgery and assessed the relationship between the patient characteristics, including parity and pregnancy, and the incidence of HGSOC precursors. All the fallopian tubes were examined by applying the Sectioning and Extensively Examining the Fimbriated End (SEE-FIM) Protocol.ResultsOf the 113 patients enrolled, 67 were gynecological and 46 were obstetric. The p53 signature was identified in 21 patients. No other precursors were identified. In a comparison of the p53 signature-positive and negative groups, parous women and pregnant women were significantly fewer in the p53 signature-positive group (53% vs. 86%, p=0.002, 10% vs. 47%, p=0.001, respectively). Current pregnancy was also associated with a significantly lower incidence of the p53 signature after multivariate adjustment (odds ratio [OR]=0.112; 95% confidence interval [95% CI]=0.017–0.731; p=0.022). Among gynecological patients, parous women were fewer in the p53 signature-positive group on univariate (47% vs. 73%, p=0.047) and multivariate analysis (OR=0.252; 95% CI=0.069–0.911; p=0.036). No other characteristics were associated with p53 signature positivity.ConclusionsThe incidence of the p53 signature was significantly lower in parous women and pregnant women. This decreased incidence of early phase serous carcinogenesis may be one of the possible mechanisms underlying HGSOC risk reduction among parous women.