Mutagenicity of nitrophenanthrene derivatives for Salmonella typhimurium: effects of nitroreductase and acetyltransferase

To determine the mutagenicity of nitrophenanthrenes, three mononitrophenanthrenes (NPhs), 11 dinitrophenanthrenes (diNPhs) and eight trinitrophenanthrenes (tiNPhs) were synthesized, and their mutagenicity was investigated by using Salmonella typhimurium his- strains TA98, TA100, and TA98NR, nitroreductase-deficient, and TA98/1,8-DNP6, O-acetyltransferase-deficient mutants, and strains YG1021 and YG1026, nitroreductase-overproducing mutants of TA98 and TA100, respectively, and strains YG1024 and YG1029, O-acetyltransferase-overproducing mutants of TA98 and TA100, respectively. 1-, 3- and 9-NPhis induced 329, 620 and 438 revertants per nmol in strain TA100, respectively, and 4,839, 11,309 and 16728 revertants per nmol, respectively, in strain YG1029. Mutagenicity of 1,6-, 2,6-, 2,9-, 2,10-, 3,5-, 3,6- and 3,10-diNPh was elevated in strains YG1021, YG1024, YG1026 and YG1029. Among these derivatives, 1,6-, 2,6-, 3,6- and 3,10-diNPhs were more mutagenic in strains YG1024 and YG1029 than YG1021 and YG1026, and they showed a structure-activity relationship between mutagenicity and NO2-substitution. Nitro derivatives substituted at the 3 and 6 positions of their chemical structure strongly mutated both strains YG1024 and YG1029, whereas those substituted at the 9 and 10 positions showed weak mutagenicity. In addition, nitro substituents at positions 4 and 5 were perpendicular while those on positions 2,3,6 and 7 were nearly coplanar to the aromatic ring. Furthermore, 2,6,9-, 3,6,9- and 1,6,9-trinitrophenanthrenes (triNPhs) were mutagenic for strain TA100, and their mutagenicity was more enhanced in YG1024 and YG1029 than in YG1021 and YG1026. Of the eight triNPhs all except 1,5,10-triNP were mutagenic in TA98 and TA100, and their mutagenicity was more enhanced in YG1024 and YG1029 than in YG1021 and YG1026. These results suggest that these compounds are mutagens that are activated by O-acetyltransferase esterification following nitroreductase. The nitrated derivatives substituted at the 2(7) and 3(6) positions of the phenanthrene ring were highly mutagenic. The relationship between chemical structure and the mutagenicity of NPh derivatives is discussed.

[Primary trabeculectomy for open-angle glaucoma with mitomycin C]

We examined the results of postoperative intraocular pressure (IOP) control and complications of trabeculectomy with mitomycin C in open angle glaucoma patients who had not undergone any other ocular surgery. The subjects were 80 eyes of 70 patients who underwent surgery with 0.04% mitomycin C as an adjunct for 3 minutes and were followed for 7-24 months (mean +/- standard deviation: 13 +/- 3.4). The preoperative IOP was 21-32 mmHg (mean +/- standard deviation: 24.6 +/- 4.3) in maximum tolerable medications. IOP control ratio, which was analysed with the Kaplan-Meier method at 24 months after surgery was 81.6% without any antiglaucoma medications, vs 92.0% with medications. These values were significantly higher (p < 0.05) than the results of trabeculectomy with 5-fluorouracil or without antimetabolic agents previously performed in our clinic. Shallow chamber in 18 eyes (23%), choroidal detachment in 14 eyes (18%), hypotonus maculopathy in 7 eyes (9%), and cataract progression in 5 eyes (7%) were recognised as complications. Although there are some complications to be conquered, trabeculectomy with mitomycin C seems to be effective in treating primary open angle glaucoma patients.

[Calculation of surgically induced astigmatism]

We compared several mathematical methods for the calculation of surgically induced astigmatism, including Jaffe's horizontal component, Jaffe's vector, Cravy's axis-based cylinder, and Holladay's with-the-wound cylinder. Computer stimulation indicated that Jaffe's vector and Holladay's with-the-wound cylinder methods correctly calculate the surgically induced astigmatism regardless of the direction of wounds. The remaining two methods, however, were found to give erroneous values when the wound is constructed off the x-y axis. Holladay's parameter was least affected by the deviation of the surgical axis. When pre- and postsurgical data of eyes undergoing cataract surgery were analyzed (55 eyes were operated on with a 5.5 mm incision located superiorly, 35 eyes with a 5.5 mm incision located supratemporally, and 40 eyes with a superiorly located 3.2 mm incision), only the Holladay's with-the-wound cylinder method could calculate the actual amount of with-and/or against-the-wound changes.

Insulin autoimmune syndrome after the third therapy with methimazole

In 1986, a 26-year-old female had been diagnosed as having Graves' disease and had been treated with methimazole for four months. After the treatment with propylthiouracil for another four months, she had been treated with methimazole once again. She was in complete remission for two years. She again experienced symptoms of hyperthyroidism, and treatment with methimazole was started again. On the thirteenth day after treatment, she experienced hypoglycemic attacks with skin eruption. The plasma glucose was 57 mg/dl, 125I-Insulin binding 69%, free IRI 196 microU/ml. The patient had the HLA-DRB1*0406.

Clinical efficacy of diclofenac sodium on postsurgical inflammation after intraocular lens implantation

We investigated the anti-inflammatory effects of 0.1% diclofenac sodium on anterior inflammation after cataract surgery. Fibrin precipitation after surgery in patients without systemic or ocular disease was markedly less when diclofenac sodium ophthalmic solution was used in combination with topical corticosteroids. There was also a reduction in fibrin precipitation in other patients, especially in those with diabetes mellitus, primary angle-closure glaucoma, and exfoliation syndrome. In conclusion, diclofenac sodium was shown to be clinically useful as a topical preparation to suppress inflammation after cataract surgery.

YM-14673, a thyrotropin-releasing hormone analogue, injected into the nucleus accumbens and the striatum produces repetitive jaw movements in rats

Bilateral injections of the thyrotropin-releasing hormone (TRH) analogue, N alpha-[((S)-4-oxo-2-azetidinyl)-carbonyl]-L-histidyl-L-prolinamide dihydrate (YM-14673, 0.1 microgram and 1 microgram/0.2 microliters), into the nucleus accumbens, the dorsal and ventrolateral striatum produced repetitive jaw movements in a dose-dependent manner. The effects were greatest in the nucleus accumbens and smallest in the ventrolateral striatum. Pattern of the movements differed from that produced by injections of a mixture of SKF 38393 (5 micrograms) and quinpirole (10 micrograms); frequent tongue protrusions were evident in rats treated with the mixture but those were not seen in YM-14673-treated rats. TRH (1 microgram, 10 micrograms and 30 micrograms/0.2 microliters) did not evoke jaw movements from any of the sites. The non-selective dopamine receptor antagonist, cis-(Z)-flupentixol (10 micrograms), significantly reduced the response to administration of YM-14673 (1 microgram) into the nucleus accumbens or dorsal striatum, while the 5-hydroxytryptamine (5-HT)2A receptor antagonist, 2-(2-dimethylaminoethylthio)-3-phenylquinoline hydrochloride (ICI 169,369, 0.2 micrograms), did not affect the response to YM-14673 (1 microgram). Given intrathecally (0.5 microgram/5 microliters), both YM-14673 and TRH produced wet-dog shakes. Although the mechanisms giving rise to the display of jaw movements after intrastriatal injections of YM-14673 remain unknown, stimulation of the dopamine D1/D2 receptors may at least partly contribute to these effects. Anyhow, these mechanisms differ from that underlying the ability of YM-14673 and TRH to elicit wet-dog shakes, a mechanism that is known to involve serotonergic processes.

[19F-MR imaging of transplanted tumor: perfluorochemicals as a fluorine tumor imaging agent]

PURPOSE

The purpose of our study was to detect tumor selectively using 19F-magnetic resonance imaging (MRI) and to assess Fluosol-DA, a perfluorochemical emulsion, as a tumor imaging agent for 19F-MRI.

MATERIALS AND METHODS

SCC VII cells were transplanted in the right leg of mice. After 6 days, Fluosol-DA was administrated intravenously (40 ml/kg). 19F-MR imaging was performed on a Bruker CSI Omega 2 at 4.7 Tesla using a homemade volume coil.

RESULTS

In vitro, the concentration and 19F signal intensity of FDA showed a very high correlation (r = 0.9997). Detection on MRI was possible at a concentration of 2%. In vivo, images of 19F in SCC VII tumors were achieved in animals 2 days after the administration of FDA.

CONCLUSION

Our study confirms the feasibility of 19F-MR in vivo imaging of tumors using the fluorine compound FDA.

Initiating activity of quinones in the two-stage transformation of BALB/3T3 cells

2-tert-Butyl-1,4-benzoquinone (BQ), a metabolite of the rodent carcinogen 3-tert-butyl-4-hydroxyanisole (3-BHA), has been shown previously to have initiating activity for cell transformation. In this paper, we examined the initiating activity of quinones in a two-stage transformation assay using BALB/3T3 cells. Cells were treated first with a quinone and then with the tumor promoter 12-O-tetra-decanoylphorbol-13-acetate (TPA). The quinones tested were 1,4-benzoquinone (pQ), phenyl-1,4-benzoquinone (PhQ), menadione and 2,5-di-tert-butyl-1,4-benzoquinone (DBQ) in addition to BQ. pQ is a metabolite of benzene and phenacetin, and PhQ is a metabolite of o-phenylphenol (OPP) and sodium o-phenylphenate (OPP-Na). All of the tested quinones induced transformation in the presence of TPA but not in its absence. The extent of transformation caused by quinones followed by TPA was weak but statistically significant. Thus these quinones were shown to act as initiators in the transformation of BALB/3T3 cells. This result suggests that BQ, pQ and PhQ may be involved in carcinogenesis by 3-BHA, benzene, phenacetin, OPP and OPP-Na in vivo. Menadione has been reported to cause cytotoxic effects and mutations through active oxygen generation from semiquinone radicals. DBQ has two bulky substitutes which interfere with covalent bonds with DNA. Menadione and DBQ exhibited initiating activity in the present study. This result suggests that active oxygens generated from semiquinone radicals may play a role in the initiation of cell transformation.

Increased number of circulating HTLV-1 infected cells in peripheral blood mononuclear cells of HTLV-1 uveitis patients: a quantitative polymerase chain reaction study

AIMS

This study aimed to characterise the status of viral infection in patients with HTLV-1 uveitis (HU) by quantifying the circulating HTLV-1 infected cells in the peripheral blood.

METHODS

Genomic DNA samples of peripheral blood mononuclear cells (PBMC) were obtained from 25 patients with HU, 14 patients with tropical spastic paraparesis/HTLV-1 associated myelopathy (TSP/HAM), and 21 asymptomatic carriers of HTLV-1. Quantitative polymerase chain reaction (PCR) of the gag region of HTLV-1 provirus DNA was performed on these DNA samples. To confirm the PCR, genomic Southern blot hybridisation was performed to identify integrated HTLV-1 provirus. This procedure detected a few percent of HTLV-1 infected cells in the PBMC.

RESULTS

Most of the HU patients had a significantly increased number of circulating HTLV-1 infected cells (mean (SD) 3.84% (4.45%) of the PBMC), whereas the percentage of infected cells in most asymptomatic carriers was less than 1% (0.54% (1.11%)). Most of the TSP/HAM patients also had a relatively high percentage (11.63% (7.67%)). The differences among these three groups were highly significant by the Mann-Whitney U test.

CONCLUSION

The results suggested that the increase in the number of HTLV-1 infected cells is one base for the development of inflammatory HU lesions, as it is for TSP/HAM.

A novel promoting action of fullerene C60 on the chondrogenesis in rat embryonic limb bud cell culture system

Fullerene C60 was solubilized with polyvinylpyrrolidone (PVP) in water, and the aqueous solution was applied to the rat limb bud cell differentiation system. By the incubation with various concentrations of C60 with poly(vinylpyrrolidone), cell differentiation was extremely promoted, up to the levels of a 3.2-fold increase of the controls. Although poly(vinylpyrrolidone) alone inhibited the cell differentiation in proportion to the concentration, the observed promoting action by C60 surpassed the action of poly(vinylpyrrolidone). This specific promoting action on the chondrogenesis is the novel significant activity of C60.

Chemical oxidation of nitrated polycyclic aromatic hydrocarbons: hydroxylation with superoxide anion radical

Nitrated polycyclic aromatic hydrocarbon (nitroPAH) is a potent mutagen which is reductively and/or oxidatively metabolized. Biological oxidation of nitroPAH, such as hydroxylation and epoxidation, is known, but chemical oxidation has been reported in only a few papers. NitroPAH is barely oxidized by various chemical oxidants because of the electron deficient property of the aromatic ring with the nitro substituent. Nucleophilic reactivity of superoxide anion radical is known, and thus the oxidation of nitroPAH with the chemically generated superoxide anion radical was carried out in this study. When 1-nitropyrene was reacted with KO2/18-crown-6 in dimethylformamide, 5-, 6-, 8-, and 9-hydroxy-1-nitropyrenes and 1-hydroxypyrene were obtained in preparative yields. Three isomeric dinitropyrenes, 3-nitrofluoranthene, 6-nitrobenzo[a]pyrene, and 6-nitrochrysene, were oxidized to hydroxy derivatives, some of which correspond to the oxidative metabolite of nitroPAH. The oxidation of dinitropyrenes with trifluoroperacetic acid gave K-region oxidized products.

Di- and trinitrophenanthrenes: synthesis, separation, and reduction property

Although nitrated polycyclic aromatic hydrocarbons (nitrated PAHs), specifically, dinitrated PAHs, have been indicated as potent mutagenic and carcinogenic environmental pollutants, only a few di- and trinitrophenanthrenes (DNPHs and TNPHs) have been reported up to the present time. Methods for the preparation of DNPHs and TNPHs by direct nitration of phenanthrene were established in this study. The reaction of phenanthrene with fuming nitric acid in acetic anhydride gave a complex mixture of DNPHs. Eleven DNPHs were isolated by using preparative HPLC with a total of 62.6% yield. Their chemical structures were determined using 1H NMR and electron impact mass spectrometry (EI-MS). The isolated DNPHs and their yields were 2,10-DNPH (14.2%), 1,10-DNPH (8.0%), 3,10-DNPH (6.9%), 3,6-DNPH (6.6%), 2,9-DNPH (5.3%), 1,6-DNPH (5.1%), 3,5-DNPH (4.6%), 4,9-DNPH (3.2%), 4,10-DNPH (3.1%), 1,5-DNPH (2.8%), and 2,6-DNPH (2.8%). Similarly, nine TNPHs were obtained from the nitrated reaction mixture of phenanthrene with fuming nitric acid without solvent: 3,6,9-TNPH (9.2%), 2,6,9-TNPH (9.0%), 1,6,9-TNPH (8.2%), 1,5,10-TNPH (9.0%), 2,6,9-TNPH (9.0%), 1,6,9-TNPH (4.0%), 1,7,9-TNPH (3.4%), 2,5,10-TNPH (2.5%), 2,6,10-TNPH (2.4%), 3,5,10-TNPH (1.8%), and 2,7,9-TNPH (0.2%) in 46.5% of the total yield. The reduction properties of the DNPHs and TNPHs were examined using cyclic voltammetry. The LUMO energy levels of the DNPHs and TNPHs calculated by the AM1 method were correlated to the first reduction potentials (E1/2). The coplanar or noncoplanar conformations of the nitro substituents to the phenanthrene ring system were also discussed.

Studies on the tumor-promoting activity of additives in biomaterials: inhibition of metabolic cooperation by phenolic antioxidants involved in rubber materials

For the detection of tumor-promoting activities of phenolic antioxidants, the inhibitory activities on the intercellular gap-junctional communication were investigated using the V79 metabolic cooperation (MC) assay. Among eight antioxidants, 4,4'-butylidene-bis(3-methyl-6-tert-butyl-phenol), 2,2'-methylene-bis(4-methyl-6-tert-butylphenol) (MBMBP), and styrenated phenol (SP) showed stronger inhibitory activities than lithocholic acid, which is known to be a tumor promotor. However, 4,4'-thio-bis(3-methyl-6-tert-butylphenol), Irganox 1010, and 1330 did not inhibit at any concentrations. When the single-electron oxidation potentials were compared among antioxidants, the electrochemical ease estimated with the first oxidation potential was correlated with the cytotoxic potentials (r = 0.88), but not with the inhibitory activities in an MC assay. The tumor-promoting activity of MBMBP was also investigated using an in vitro, two-stage Balb/c 3T3 transformation assay. MBMBP did not show initiating activity, but significant promoting activity at concentrations of both 1 and 2.5 micrograms/ml were noted. These concentrations were close to the lowest effective inhibitory concentration (1.3 micrograms/ml) of MBMBP in an MC assay. In conclusion, there is a possibility that the phenolic antioxidants that show inhibitory activities in an MC assay contribute to the enhancement of tumor incidence induced by biomaterials.

Multidirectional contraction of human hypertrophied prostate

1. The purpose of the present investigation is to evaluate muscle contraction in two directions (longitudinal and circumferential to urethra) physiologically and morphologically for alpha-adrenoceptor agonists. 2. Norepinephrine (10(-7)-10(-4) M), phenylephrine (10(-7)-10(-4) M) and clonidine (10(-7)-10(-4) M) induced contractions in a dose-dependent manner on human prostate from patients with benign prostatic hypertrophy (BPH). 3. No significant differences were observed between longitudinal and circumferential directions of human prostate in 50% of the maximal muscle contraction (EC50 values) and the maximal muscle contractions caused by any agents used. 4. Morphometric analysis for muscle in prostates was performed using formalin-fixed, paraffin-embedded sections stained by the Mallory-Azan method. 5. There was no significant difference in the density of the muscle area between longitudinal and circumferential directions of prostatic strips. 6. These results suggest that there are no significant differences in responsiveness of alpha-adrenoceptor agonists and the smooth muscle contents in longitudinal and circumferential directions to urethra, for human hypertrophied prostate.

[Thermotolerance and heat shock protein (HSP 70) in vascular endothelial cells]

Recently, it was determined that the endothelial cells of blood vessel play a very important physiological role in the regulation of blood coagulation and selective permeability. To study the thermotolerance of vascular endothelial cells, human umbilical vein endothelial cells (HUVEC) were heated at 40, 43, 45 or 50 degrees C for various lengths of time with or without preheating at 40 or 43 degrees C for 30 min. The cell viability (CV) of HUVEC decreased gradually according to heating time. However, the CV of preheated HUVEC decreased slightly or not at all. Heat shock protein (HSP) in HUVEC heated at 37, 40, 43, or 45 degrees C was examined by immunoblotting. A new HSP 70 band was detected in HUVEC by heating at 40, 43 or 45 degrees C. HUVEC revealed thermotolerance with induction of HSP by heat stress.

Effects of CD-832, a dihydropyridine derivative with a nitrate ester moiety on rabbit femoral artery and vein

We investigated the effects of CD-832 ((4R)-(-)-2-(nicotinoyl-amino)ethyl 3-nitroxypropyl 1,4-dihydro-2,6-dimethyl-4,3-nitrophenyl, 3,5-pyridine dicarboxylate), a dihydropyridine derivative with a nitrate ester moiety, on contractile responses in rabbit femoral arteries and veins. CD-832 (10(-8) to 10(-6) M and nifedipine inhibited the 64 mM KCl-induced and 10(-6) M norepinephrine-induced contractions of rabbit femoral arteries, while nitro compounds had no effect on the contractions. CD-832 (10(-8) to 10(-6) M) and nitro compounds inhibited the 10(-6) M norepinephrine-induced contractions in rabbit femoral veins, while other Ca2+ channel antagonists had little effect. The inhibitory effects of CD-832 (10(-7) M) on norepinephrine-induced contractions were antagonized by treatment with methylene blue (10(-5) M). These results indicate that CD-832 potently relaxes venous smooth muscle, and that it may be a useful agent for the treatment of angina pectoris.

Human T-lymphotropic virus type I uveitis

In addition to adult T-cell leukemia (ATL) and chronic myelopathy (HAM/TSP), our current study indicates that human T lymphotropic virus type I (HTLV-I) is a causative agent for a specific type of uveitis with unknown etiology (idiopathic uveitis). The present paper describes the seroepidemiological, clinical, and molecular biological evidences that indicate uveitis seen in HTLV-I asymptomatic carriers (HTLV-I uveitis) is a distinct clinical entity. In an HTLV-I endemic area in Japan, the seroprevalence of HTLV-I in idiopathic uveitis was 38%, while those in uveitis with defined etiology and in non-uveitic ocular diseases were 10% and 19%, respectively. Strikingly, the HTLV-I seroprevalence in younger aged patients (20-49 years) with idiopathic uveitis was 49%, while only 8% in the control group (P < 0.001). A very similar observation was recorded even in HTLV-I less endemic area, suggesting that HTLV-I infection plays a role as a risk factor for idiopathic uveitis. Clinical analysis revealed that an intermediate uveitis characterized by moderate opacities in the vitreous body and retinal vasculitis was seen in the majority the patients. The proviral DNA of HTLV-I was detected from inflammatory cells in the eye of all tested patients using PCR technique. These data thus indicate that HTLV-I is closely related to a certain type of uveitis and the uveitis (HTLV-I uveitis) is a distinct clinical entity.

Role of cyclic GMP in inhibitory effects of CD-349 in isolated blood vessels

1. We investigated the effects of CD-349, a dihydropyridine derivative with nitrate ester, on contractile responses induced by high K+, norepinephrine (NE) and Ca2+ in isolated rabbit aorta. 2. CD-349 (10(-9)-10(-5) M) and nifedipine (10(-9)-10(-5) M) equally inhibited the 64 mM KCl-induced contraction of the aortic strips in a concentration-dependent manner. 8-Br-cyclic GMP (10(-3) M) did not inhibit the KCl-induced contraction of the aortic strips. 3. CD-349 (10(-8)-10(-5) M) and 8-Br-cyclic GMP (10(-6)-10(-3) M) inhibited the 10(-6) M NE-induced contraction of the aortic strips in a concentration-dependent manner. However, nifedipine had no effect on the NE-induced contraction in rabbit aorta. 4. The inhibitory effects of CD-349 on NE-induced contraction were antagonized by treatment with methylene blue and oxyhemoglobin, while they were augmented by treatment with zaprinast. 5. CD-349 (10(-8)-10(-5) M) and 8-Br-cyclic GMP (10(-5)-10(-4) M) inhibited the NE-induced phasic contraction and Ca(2+)-induced contraction of the aortic strips preincubated with NE in Ca(2+)-free medium. However, nifedipine (10(-5) M) had little or no effect on both NE-induced phasic contraction and Ca(2+)-induced contraction of the aortic strips preincubated with NE in Ca(2+)-free medium. 6. CD-349 (10(-7)-10(-5) M) increased the levels of cyclic GMP in rabbit aorta. 7. These results indicate that CD-349 has a hybrid property deriving from Ca(2+)-antagonist and cyclic GMP increasing agents.

Mycosis fungoides with Leser-Trélat sign: the first report of a patient from Japan

We describe here a 35-year-old Japanese woman with mycosis fungoides (MF) who developed numerous, rapidly-growing, seborrheic keratoses on the front of her neck and chest. To the best of our knowledge, this is the first reported case of MF with Leser-Trélat sign from Japan.

Human T lymphotropic virus type 1 uveitis after Graves' disease

A distinct clinical entity of uveitis associated with human T lymphotropic virus type 1 (HTLV-I) has been reported previously. During the period between January 1989 and April 1992, 93 patients were observed with HTLV-I uveitis and a significant correlation was found between Graves' disease and HTLV-I uveitis. Sixteen of the 93 patients with HTLV-I uveitis (17.2%) had a previous history of Graves' disease. Fifteen patients were female (15/60, 25.0%) and one was male (1/33, 3.0%). Interestingly, uveitis occurred after the onset of Graves' disease in all cases. On the other hand, none of 222 patients with idiopathic uveitis who were seronegative to HTLV-I had a history of Graves' disease. Although the mechanisms by which HTLV-I causes the correlation between uveitis and Graves' disease are unknown, the present data suggest that immune mediated or autoimmune mechanisms are involved in HTLV-I uveitis.

Combined paraumbilical perforator skin flap and vascularized pubic bone graft

A severely depressed deformity of the buccal region was repaired with an osteocutaneous flap based on the deep inferior epigastric vessels. This osteocutaneous flap has not been previously described in the literature. The superior pubic ramus, supplied by pubic branches from the deep inferior epigastric vessels, forms the bony portion of the combined flap. The cutaneous portion is also supplied by the deep inferior epigastric vessels and its thickness can be adjusted. This combination is useful when requiring both a thin flap and a flat bone.

Detection of nitro-azabenzo[a]pyrene derivatives in the semivolatile phase originating from airborne particulate matter, diesel and gasoline vehicles

Mutagens in the semivolatile phase of airborne particulate matter, diesel and gasoline engine emissions were investigated using chemical and biological assays. The previously unknown mutagens, 1-(3-)nitro-6-azabenzo[a]pyrenes (1-N-6-ABP and 3-N-6-ABP) and 1-(3-)nitro-6-azabenzo[a]pyrene-N-oxides (1-N-6-ABPO and 3-N-6-ABPO), were detected in the semivolatile phase, which was adsorbed onto XAD-4 resin combined with a Teflon-coated fibre filter. Dichloromethane extracts of materials adsorbed onto XAD-4 resin were divided into acidic, neutral and basic by liquid-liquid separation. These chemicals in the basic fraction were the major mutagens in the semivolatile phase when they were bioassayed using Salmonella typhimurium TA98 in the absence of S9 mix; the mutagenicity of the basic fraction contributed at the rate of 42.9-68.8% of that of crude extracts for airborne, diesel and gasoline emission materials. As the mutagens were found to be difficult to analyse by gas chromatography (because of their probable absorption onto the packing) they were purified by HPLC and analysed by mass spectrometry. The concentrations of 1-N-6-ABP, 3-N-6-ABP, 1-N-6-ABPO and 3-N-6-ABPO detected were 1.1, 1.2, 0.8 and 0.3 ng/g, respectively, of materials in the airborne sample, and 4.9, 7.7, 2.2 and 3.8 ng/g, respectively, of materials in the diesel emission. Only 1-N-6-ABP (3.4 ng/g) and 3-N-6-ABP (4.9 ng/g) were detected in the semivolatile phase of the gasoline engine emission.(ABSTRACT TRUNCATED AT 250 WORDS)

CD-832, a new dihydropyridine derivative with both nitrate-like and Ca2+ channel antagonist vasodilator activities

We investigated the effects of CD-832 ((4R)-(-)-2-(nicotinoylamino)ethyl 3-nitroxypropyl 1,4-dihydro-2,6-dimethyl-4,3-nitrophenyl, 3,5-pyridine dicarboxylate), a new dihydropyridine derivative with nitrate ester, on contraction and relaxation responses induced by various vasoactive agents in rabbit aorta. CD-832 potently inhibited the specific binding of [3H](+)-PN200-110 to rat brain membranes. The IC50 values for [3](+)-PN200-110 binding were 2.8 nM and 4.9 nM in CD-832 and nifedipine, respectively. CD-832 (10(-8) to 10(-5) M), diltiazem (10(-8) to 10(-5) M) and benidipine (10(-8) to 10(-5) M) inhibited the 64 mM KCl-induced contraction of the aortic strips in a concentration-dependent manner. Neither nitroglycerin (10(-8) to 10(-5) M) nor nicorandil (10(-8) to 10(-5) M) affected the 64 mM KCl-induced contraction in rabbit aorta. CD-832 (10(-8) to 10(-5) M), nitroglycerin (10(-8) to 10(-5) M) and nicorandil (10(-5) M) had no effect on norepinephrine-induced contraction in rabbit aorta. Nitroglycerin (10(-5) M), atrial natriuretic peptide (10(-8) M), nicorandil (10(-5) M) and CD-832 (10(-7) to 10(-5) M) augmented the isoproterenol-induced relaxation responses of rabbit aorta precontracted with endothelin-1 (1 x 10(-7) to 2 x 10(-7) M). The effects of nitroglycerin (10(-5) M), nicorandil (10(-5) M) and CD-832 (10(-5) M) on isoproterenol-induced relaxation responses were antagonized by treatment with methylene blue (10(-5) M) and oxyhemoglobin (10(-5) M).(ABSTRACT TRUNCATED AT 250 WORDS)

Familial clustering of human T lymphotropic virus type 1 uveitis

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