Dermal absorption of kerosene components in rats and the influence of its amount and area of exposure

The influences of amount and area of dermal exposure to kerosene upon the levels of kerosene components in biological samples were examined in vivo and in vitro. Thirty-two rats were randomly divided into four groups and exposed to kerosene through the abdominal skin for 2h. The amounts (soaked in cotton) and area of kerosene exposed were 1 ml/4 cm(2) in Group I, 4 ml/4 cm(2) in Group II, 4 ml/16 cm(2) in Group III and 16 ml/64 cm(2) in Group IV. Before, then 5, 10, 20, 30, 45, 60, 90 and 120 min after exposure, 0.5 ml of blood was collected. Solid tissue samples, including the exposed skin area, were harvested at 120 min. Kerosene components were analyzed by gas chromatography/mass spectrometry. Trimethylbenzens (TMBs) that are easily absorbed kerosene components, appeared at 5-20 min. The time course changes in TMB levels in blood were significantly different between Groups I and II or Groups I and III, and almost identical between Groups II and III. Similar trends were observed in tissue samples at 120 min. High concentrations of aliphatic hydrocarbons (AHCs) were detected in the exposed skin and the AHC levels were dependent on the amount of kerosene exposed per unit area. These results suggest that (1) dermal absorption of kerosene occurs soon after dermal exposure started, (2) absorption of TMBs is influenced by the total amount of kerosene rather than area of exposure, and (3) AHCs remaining in the skin at significant levels are influenced by the amount of kerosene per unit area exposed.

Higher radical scavenging activities of polyphenolic antioxidants can be ascribed to chemical reactions following their oxidation

Radical scavenging activities of 34 natural antioxidants were investigated from an electrochemical viewpoint. While the correlation of the oxidation potentials with their DPPH radical scavenging activities (represented by EC(50)) was not high (the correlation coefficient, r=0.73), the number of electrons n required for oxidation of an antioxidant, being obtained by continuous flow-column electrolysis with a slower flow rate (0.05 ml min(-1)), did show a good correlation with EC(50) (1/EC(50)=1.67n+0.50 with r=0.94). The n values of most polyphenols were increased with a decrease in the flow rate, while those of nonpolyphenols were invariant. This suggests that a slower subsequent chemical reaction(s) should be involved in the oxidation of polyphenols, whose higher radical scavenging activities seem to be ascribed to the chemical reactions. In this study, we have proposed a possible mechanism for the oxidation of polyphenols, in which the oxidizable -OH moieties are reproduced through an oxidative dimerization (or more highly polymerization).

Distribution of kerosene components in rats following dermal exposure

The systemic distribution of kerosene components in blood and tissues was analysed in rats following dermal exposure. Four types of trimethylbenzenes (TMBs) and aliphatic hydrocarbons (AHCs) with carbon numbers 9-16 (C(9)-C(16)) were analysed as major kerosene components by capillary gas chromatography/mass spectrometry (GC/MS). The kerosene components were detected in blood and all tissues after a small piece of cotton soaked with kerosene was applied to the abdominal skin. The amounts of TMBs detected were higher than those of AHCs. Greater increases in TMB levels were found in adipose tissue in an exposure duration-dependent manner. The amounts of TMBs detected were only at trace levels following post-mortem dermal exposure to kerosene. These findings suggest that kerosene components were absorbed percutaneously and distributed to various organs via the blood circulation. Post-mortem or ante-mortem exposure to kerosene could be distinguished when the exposure duration was relatively long. Adipose tissue would seem to be the most useful for estimating the degree of kerosene exposure.

Mechanistic study of the oxidation of caffeic acid by digital simulation of cyclic voltammograms

The oxidation mechanism of caffeic acid (CAF) has been studied by means of cyclic voltammetry with the plastic formed carbon or glassy carbon electrode. CAF gives a well-developed two-electron reversible wave in acidic media, whereas it shows an irreversible behavior, i.e., a decrease of the rereduction peak, in less acidic media, suggesting that the oxidation of CAF follows an irreversible chemical reaction(s). Digital simulation analyses based on different oxidation mechanisms have been performed for the voltammograms obtained with the GC electrode in 1:1 (v/v) water:ethanol solutions. The results clearly show that the seeming two-electron oxidation of CAF occurs stepwise via one-electron processes, each of which follows an irreversible chemical reaction. It has also been suggested that the semiquinone radical as an intermediate of the one-electron oxidation should play an important role in the oxidation reaction. Evaluations of the rate constants for the chemical reactions have further suggested that the chemical reactions are dimerization reactions.

Vitamins D and K in the treatment of osteoporosis secondary to graft-versus-host disease following bone-marrow transplantation

We report a case of secondary osteoporosis treated with a combination of vitamins D3 and K2, administered orally. A 13-year-old male, diagnosed with highly differentiated acute myelogenous leukaemia, received an allogeneic bone-marrow transplantation. Chronic graft-versus-host disease persisted, thereafter, in the form of severe diarrhoea, rash and allergic conjunctivitis. Since the patient was then at risk from osteoporosis secondary to calcium malabsorption caused by the diarrhoea, dual-energy X-ray absorptiometry and ultrasound analysis were used to measure bone mineral density and bone stiffness, respectively. Both measurements were markedly lower than the average values from patients of matched age, gender and physical characteristics. The osteoporosis did not respond to active vitamin D3 0.1 microg/kg once daily, but when this therapy was combined with vitamin K2 15 mg once daily, an increase in bone mineral density and bone stiffness was observed. In conclusion, vitamin D3 and K2 combination therapy merits further evaluation for the treatment of various types of secondary osteoporosis, including steroid-induced osteoporosis.

Unusually large numbers of electrons for the oxidation of polyphenolic antioxidants

Reaction mechanisms of polyphenolic antioxidants were studied using electrochemical methods (flow column electrolysis and cyclic voltammetry). In flow column electrolysis, the numbers (ns) of electrons involved in the oxidation of catechols (chlorogenic acid and caffeic acid) became larger than two (i.e. the number of -OH moieties) at pH > 7; the n-values finally reached ca. 4 at pH 10. Other polyphenols including catechin, ellagic acid, and curcumin exhibited higher n-values than the numbers of -OH moieties in the whole pH range studied (4 < pH < 10). Such unusually large n-values for polyphenols were found to correlate to their irreversible behavior in cyclic voltammetry. A digital simulation analysis of the voltammograms of chlorogenic acid clearly showed that the electrode reaction at higher pHs can be elucidated in terms of a quasi-reversible electron transfer followed by a chemical reaction and also suggested that the chemical reaction is of second order to the concentration of chlorogenic acid, i.e. a dimerization reaction. In a similar manner, polyphenolic antioxidants generally undergo certain chemical reactions on the occasion of their oxidation. As a result, some oxidizable, phenolic -OH moieties are reproduced in the polymeric products. The unusually large n-values of polyphenols and thus their higher radical scavenging activities may be ascribed to such reproduction of -OH moieties by oxidative polymerization.

Hyperexpression of the gene for a Bacillus alpha-amylase in Bacillus subtilis cells: enzymatic properties and crystallization of the recombinant enzyme

We have constructed a new excretion vector, pHSP64, to develop a hyperexcretion system for Bacillus subtilis [Sumitomo et al., Biosci. Biotech. Biochem., 59, 2172-2175 (1995)]. The structural gene for a novel liquefying semi-alkaline alpha-amylase from the alkaliphilic Bacillus sp. KSM-1378 was amplified by PCR. It was cloned into a SalI-SmaI site of pHSP64 and the recombinant plasmid obtained was introduced into B. subtilis. The transformed B. subtilis hyperproduced the alpha-amylase activity extracellularly, corresponding to approximately 1.0 g (5 x 10(6) units) per liter of an optimized liquid culture. The recombinant enzyme was purified to homogeneity by a simple purification procedure with very high yield. No significant differences in physiochemical and catalytic properties were observed between the recombinant enzyme and the native enzyme produced by Bacillus sp. KSM-1378. The enzymatic properties of the recombinant enzyme were further examined with respect to the responses to various metal ions. The recombinant enzyme could easily be crystallized at room temperature within one day in a buffered solution of 10% (w/v) ammonium sulfate (pH 6.5).

Inhibitory effects on Epstein-Barr virus activation of anthraquinones: correlation with redox potentials

The redox potentials have been determined for nine anthraquinones in phosphate buffer at pH 7.2 by means of cyclic voltammetry. A definite correlation has been found between the redox potentials and the inhibitory effects of the anthraquinones on the EBV-EA activation. It has further been shown that the correlation can be made better by introducing an electronic property, i.e. the atomic charge at O12 as an additional parameter.

Lymphoblastic transformation of chronic myelomonocytic leukemia in an infant

A 10-month-old infant with chronic myelomonocytic leukemia (CMML) of 5 months' duration, who had been treated only with transfusion, displayed leukemic transformation characterized by lymphoid morphology, PAS positivity, and myeloperoxidase negativity. Surface marker analysis of blast cells revealed expression of lymphoid-associated antigens (CD10 and CD19) but not myeloid-associated antigens (CD13, CD14, and CD33). These findings suggest that some cases of infantile CMML are clonal disorders arising in a pluripotent stem cell that can also differentiate along the lymphoid cell lineage.

Ganglioside-like epitopes of lipopolysaccharides from Campylobacter jejuni (PEN 19) in three isolates from patients with Guillain-Barré syndrome

Sera from patients with Guillain-Barré syndrome (GBS) frequently have anti-GM1 antibody. We earlier showed that an lipopolysaccharides (LPS) from Campylobacter jejuni (PEN 19) isolated from a GBS patient has a GM1 ganglioside-like structure. Aspinall et al. (Biochemistry, 61 (1994) 335-337) reported that OH 4382 has an LPS that bears a CD3 ganglioside-like structure and that OH 4384 has an LPS that bears a GT1a-like structure; both strains were isolated from patients with GBS. They also suggested a GM1-like structure is present in the LPSs from OH 4384, but failed to show the presence in the LPSs from OH 4382. To clarify the pathogenesis of GBS after infection by C. jejuni (PEN 19), we investigated the carbohydrate structures of the three strains by thin-layer chromatography immunostaining with cholera toxin and monoclonal anti-ganglioside antibodies. We found that both OH 4382 and OH 4384 have an LPS with the GM1 epitope as well as one with the GT1a or GD3 epitope.

Production of the phytotoxic metabolite, ferricrocin, by the fungus Colletotrichum gloeosporioides

A siderophore was isolated as a non-specific phytotoxic compound from a culture of Colletotrichum gloeosporioides isolated from infected blackberry. This siderophore was identified as ferricrocin by NMR, IR, MS, and CD spectra. The phytotoxic activities of ferricrocin and deferriferricrocin were compared.

[A case of pontine hematoma with Foville's syndrome in childhood]

We reported a surviving case of 6-year-old boy with pontine hematoma. He complained of headache as an initial symptom and developed progressively Foville's syndrome with impairments of the IX-XII cranial nerves. Although brainstem tumor was suspected initially using CT scan, MRI revealed the existence of hematoma in the ventromedial pons. During the first 4 months of his clinical course, Gd-DTPA did not demonstrate any enhancement in that lesion. However, hemangiomatous lesion was suspected by subsequent serial MRIs with positive Gd-DTPA enhancement. Using conservative treatment including oral corticosteroids, all the neurological deficits disappeared in several months and he did not show any recurrence of clinical signs for 3 years. It was suggested that MRI was very useful in the differential diagnosis and the follow-up of hematoma in the posterior fossa.

Generation of self HLA-DR-specific CD3+CD4-CD8+ cytotoxic T cells in chronic graft-versus-host disease

To analyze the mechanism of chronic graft-versus-host disease (GVHD) characteristic of autoimmune disease, we used a cell-mediated lympholysis assay to study the autoreactivity of PBL from two patients after MHC-matched BMT. Our data indicate the induction of CD3+CD4-CD8+ autoreactive cytotoxic T lymphocytes (CTL) in the one patient with chronic GVHD and an important role for allo-non-MHC (minor histocompatibility) antigen-specific CD3+CD4+CD8- helper T cells in this induction. Experiments using HLA-DR gene-transfected mouse L cells as target cells and blocking assays with anti-HLA class I and class II antibodies provided evidence that autoreactive CTL recognized HLA-DR antigen on autologous cells. Analysis of antigen-specific T cell proliferative responses in these patients to examine the effect of self HLA-DR-specific CTL on the antigen presenting cell (APC)-T cell interaction suggested that donor bone marrow-derived self HLA-DR-specific CTL are responsible for the decreased antigen-presenting ability of the patient's APC. These results suggest a new interpretation of the induction mechanism of chronic GVHD and its associated immunosuppression after MHC-matched BMT based on diminished APC function.

Antioxidative effects of dihydro-gamma-pyronyl-triterpenoid saponin (chromosaponin I)

Chromosaponin I (CSI), the naturally occurring form of soyasaponin I, inhibited the oxidation of soybean phosphatidylcholine liposomal membranes induced by a water-soluble radical initiator, 2,2'-azobis(2-amidinopropane) dihydrochloride. The antioxidative activity of CSI was similar to that of urate. Soyasaponin I, a degraded product of CSI, which has previously been thought to be an antioxidant, exerted no antioxidative activity.

Intravascular papillary endothelial hyperplasia on the penis: report of a case

An 82-year-old Japanese man with intravascular papillary endothelial hyperplasia on the penis is described. To the best of our knowledge, this is the first report of a patient who developed this tumor on his penis.

Effects of mast cell growth factor, interleukin-3, and interleukin-6 on human primitive hematopoietic progenitors from bone marrow and cord blood

Phycoerythrin (PE)-labeled murine monoclonal antibodies (MAB) to CD2, CD10, CD19, CD20, and CD33 were used as lineage markers, as were PE-labeled anti-DR MAB and fluorescein isothiocyanate (FITC)-conjugated MAB to CD34. One hundred CD34+Lin+DR+ or CD34+Lin-DR- cells were individually sorted and incubated without adherent cell layer in alpha-medium with or without cytokines such as 100 U/mL recombinant human interleukin-3 (rhIL-3), 100 U/mL rhIL-6, and/or 500 ng/mL mast cell growth factor (MGF). The incubated cells were harvested and cultured in medium containing methylcellulose every 2 weeks. The numbers of colonies from colony-forming units-granulocyte/macrophage (CFU-GM), burst-forming units-erythroid (BFU-E), and mixed colony-forming units (CFU-Mix) were scored on day 14. In the incubation, CD34+Lin-DR- cells from bone marrow and cord blood produced more CFU-GM and BFU-E, and for longer periods, than did CD34+Lin+DR+ cells. In addition, CD34+Lin-DR- from cord blood supplied more CFU-GM and BFU-E than did CD34+Lin-DR- from bone marrow. Although these data demonstrate that MGF, IL-3, and IL-6 synergistically stimulate the production of CFU-GM and BFU-E, this study indicates that CD34+Lin-DR- cells contain more primitive hematopoietic progenitors and that CD34+Lin-DR- cells are unable to maintain their self-renewal capacity in the presence of IL-3, IL-6, and MGF without adherent cell layer.