An analytical method for monitoring 10 phthalic acid monoesters in river water was investigated by solid-phase extraction, methylation with diazomethane, and GC-MS. Two cartridge-type solid phases packed with octadesyl-coated silica (C18) and styrenedivinyl polymer (PS-2) and one disk-type solid phase made from octadesyl-coated styrenedivinylbenzene polymer (SDB-XD) were investigated in solid-phase extraction. PS-2 gave the highest recoveries of the three solid phases, and recoveries of more than 80% of the monoesters in filtered water samples were obtained at pH 2 to 3 with PS-2 at the spiked level of 0.1 microg L(-1), except for monomethyl-phthalate (MMP), in which more than 72% of the monoesters were recovered. For the monoesters in the suspended solids (SS), an acidic methanol extract of SS was added to purified water acidified to pH 2, and the monoesters were extracted with PS-2. The recoveries of the monoesters in SS were more than 80%, but the recoveries of MMP were more than 57%. The method detection limit (MDL) of each phthalic acid monoester in 500 mL of water sample and in 2 mg of dry weight of SS ranged from 0.010 to 0.030 microg L(-1) and from 1 to 11 microg g(-1), respectively. Monitoring of phthalic acid monoesters in the Tama River in Tokyo was conducted every month from March 1999 to February 2000 using the present method. MMP, mono-n-butyl-phthalate (MBP), and mono-(2-ethylhexyl)-phthalate (MEHP) were detected at concentrations of 0.030-0.0340, 0.010-0.480, and 0.010-1.30 microg L(-1), respectively, in the filtered water samples but were not detected in SS. Dimethyl-phthalate (DMP), di-n-butyl-phthalate (DBP), and di-(2-ethylhexyl)-phthalate (DEHP) were detected in the river water at concentrations of 0.010-0.092, 0.008-0.540, and 0.013-3.60 microg L(-1), respectively. Diethyl-, di-iso-butyl-, and benzylbutyl-phthalates were also detected at concentrations of nanograms per liter, whereas the corresponding monoesters did not appear. The concentrations of MBP and MEHP in the river water were slightly lower than those of the corresponding diesters at the majority of sampling sites and sampling times.

Changes in fatty acid oxidation of peroxisomes in the liver of alloxan-diabetic rats were studied. After injection of alloxan (150 mg/kg, subcutaneously), the activity of peroxisomal cyanide-insensitive beta-oxidation increased more rapidly than that of carnitine palmitoyltransferase, which was the rate-limiting step of mitochondrial beta-oxidation, and reached 3 times the control level at 7 days after the treatment. The peroxisomal beta-oxidation activity was more potent toward medium chain acyl-CoAs (C=10 and 12), though it was extremely low for shorter chain lengths. The activity of carnitine acetyltransferase increased to 2.4 times the control level and the change appeared mainly in the peroxisomal fraction. On the other hand, the activity of palmitoyltransferase increased to twice the control level, distributed mostly in the mitochondrial fraction. The activity of carnitine acyltransferase increased mainly in the peroxisomal fraction, and was higher for shorter and medium chain acyl-CoAs. These results suggest that peroxisomal fatty acid oxidation and transport of acetyl-CoA and medium chain acyl-CoA as well as NADH product in peroxisomes may be rapidly enhanced in response to the demand of organs for the urgent supply of energy from fatty acids in the diabetic condition.

A human T-cell line producing human T-cell leukemia virus type I (HTLV-I), MT-2, was injected intravenously into female F344 rats aged 5 weeks to make HTLV-I carrier rats. Antibody against HTLV-I was detected at the 5th week after MT-2 injection, and its titer reached a high plateau which continued from the 15th to the 27th week. The antibodies were against p19, p24, p28 and p53 of HTLV-I antigens from MT-2 cells. The gag, pX and LTR nucleotide sequences of HTLV-I provirus were demonstrated by using polymerase chain reaction (PCR) in the peripheral-blood mononuclear cells of 3 rats at the 44th week and 2 at the 66th to 68th week out of 8 F344 rats injected with MT-2 cells. Quantification of the HTLV-I proviral sequence revealed that 30 to 60 molecules were present in 10(5) peripheral-blood mononuclear cells, indicating that the rats were chronically infected with HTLV-I. HTLV-I-infected rats could serve as a small-animal model for studying the pathophysiological state of HTLV-I carriers and also that of HTLV-I infection on various HTLV-I-related diseases, including adult T-cell leukemia and HTLV-I-associated myelopathy.

Organic solute carrier protein 1 (OSCP1) is a recently described human gene that facilitates the transport of various organic solutes into the cell, when expressed in frog eggs. In this study, we cloned a mouse ortholog of OSCP1 encoding 379 amino acid protein, with 94% homology to the human counterpart. The mouse OSCP1 mRNA was predominantly expressed in the testis, in which it was attributed to the spermatogenic cells, except the spermatogonia. Immunohistochemistry confirmed that OSCP1 protein is continuously expressed during spermatogenesis in a stage- and cell type-specific manner, in the leptotene spermatocytes at stage IX through step 15 spermatids. Subcellular fractionation of mouse testis homogenates indicated that OSCP1 is a 45-kDa cytosolic protein. Moreover, when green fluorescent protein-OSCP1 fusion constructs were transfected into cultured cells, the fluorescence localized evenly in the cytoplasm. These results suggest that mouse testis OSCP1 may indirectly mediate substrate uptake into meiotic and spermiogenic germ cells, within the cytosol.

An acyl-CoA hydrolase, referred to as hBACH, was purified from human brain cytosol. The enzyme had a molecular mass of 100 kDa and 43-kDa subunits, and was highly active with long-chain acyl-CoAs, e.g. a maximal velocity of 295 micromol/min/mg and K(m) of 6.4 microM for palmitoyl-CoA. Acyl-CoAs with carbon chain lengths of C(8-18) were also good substrates. In human brain cytosol, 85% of palmitoyl-CoA hydrolase activity was titrated by an anti-BACH antibody, which accounted for over 75% of the enzyme activity found in the brain tissue. The cDNA isolated for hBACH, when expressed in Escherichia coli, directed the expression of palmitoyl-CoA hydrolase activity and a 44-kDa protein immunoreactive to the anti-BACH antibody, which in turn neutralized the hydrolase activity. The hBACH cDNA encoded a 338-amino acid sequence which was 95% identical to that of a rat homolog. The hBACH gene spanned about 130 kb and comprised 9 exons, and was mapped to 1p36.2 on the cytogenetic ideogram. These findings indicate that the long-chain acyl-CoA hydrolase present in the brain is well conserved between man and the rat, suggesting a conserved role for this enzyme in the mammalian brain, and enabling genetic studies on the functional analysis of acyl-CoA hydrolase.