Comparative metabolism of the aza polynuclear aromatic hydrocarbon dibenz[a,h]acridine by recombinant human and rat cytochrome P450s.

To assess the role of human and rat cytochrome P450s in the metabolism of aza-polynuclear aromatic hydrocarbons (aza-PAHs) and to examine the influence of heterocyclic nitrogen on the metabolism of these chemicals, we have investigated the biotransformation of dibenz[a,h]acridine (DB[a,h]ACR), an aza-PAH with two nonidentical bay regions, by recombinant human cytochromes P450 1A1, 1B1, and 3A4 and rat P450 1A1. Among the three P450s, 1A1 was the most effective in metabolizing DB[a,h]ACR followed by 1B1 and 3A4. The major DB[a,h]ACR metabolites produced by human P450 1A1 and 1B1 were the dihydrodiols with a bay region double bond, namely, DB[a,h]ACR-3,4-diol and DB[a,h]ACR-10,11-diol (putative proximate carcinogen).

Effects of cadmium(II) on (+/-)-anti-benzo[a]pyrene-7,8-diol-9,10-epoxide-induced DNA damage response in human fibroblasts and DNA repair: a possible mechanism of cadmium's cogenotoxicity.

Cadmium, a widespread environmental pollutant and a cigarette smoke constituent, enhances the genotoxicity of benzo[a]pyrene (BP). The mechanism(s) underlying the potentiation of BP-induced genotoxicity by Cd2+ is not clearly understood. Our studies of the effects of noncytotoxic concentrations of Cd2+ on the levels of p53 and p21 in (+/-)-anti-benzo[a]pyrene-7,8-diol-9,10-epoxide (BPDE)-treated human fibroblasts showed that Cd2+ decreased BPDE-induced p21 levels in a dose-dependent manner whereas p53 accumulation is attenuated only at higher noncytotoxic concentrations of cadmium.

Mutagenicity of benzo[b]phenanthro[2,3-d]thiophene (BPT) and its metabolites in TA100 and base-specific tester strains (TA7001-TA7006) of Salmonella typhimurium: evidence of multiple pathways for the bioactivation of BPT.

Benzo[b]phenanthro[2,3-d]thiophene (BPT), and a number of its metabolites, including BPT-3,4-diol, BPT sulfoxide, BPT sulfone, and 3-hydroxyBPT were assessed for their mutagenic activity in Salmonella typhimurium strain TA100, and S. typhimurium base-specific strains TA7001, TA7002, TA7003, TA7004, TA7005, and TA7006. Among the compounds tested in strain TA100, BPT, BPT sulfone, and 3-hydroxyBPT did not show any significant mutagenic response in the presence of S9.

Metabolism of the polynuclear sulfur heterocycle benzo[b]phenanthro[2,3-d]thiophene by rodent liver microsomes: evidence for multiple pathways in the bioactivation of benzo[b]phenanthro[2,3-d]thiophene.

Benzo[b]phenanthro[2,3-d]thiophene (BPT), a thia analogue of dibenz[a,h]anthracene (DBA), is a carcinogenic environmental pollutant. We have examined the metabolism of BPT by rodent liver microsomes to investigate the mechanism by which BPT produces mutagenic and carcinogenic effects. Both rat and mouse liver microsomes biotransformed [G-(3)H]BPT to various metabolites including BPT 3,4-diol and BPT sulfoxide, which are significantly more mutagenic than the parent compound.

Metabolism of phenanthrene by brown bullhead liver microsomes.

We have investigated the regio- and stereoselective metabolism of phenanthrene by the liver microsomes of brown bullhead (Ameriurus nebulosus), a bottom dwelling fish species. The liver microsomes from untreated and 3-methylcholanthrene (3-MC)-treated brown bullheads metabolized phenanthrene at a rate of 14.1 and 20.

The relationship between driver aggression, violence, and vengeance.

A distinction is made between mild driver aggression and driver violence as unique constructs that differ mainly in frequency of occurrence and severity of outcome. Drivers completed questionnaires assessing the likelihood of engaging in mild driver aggression, the frequency of past driver violence, driving vengeance, and willful violations. Violence was predicted by the interaction of mild aggression and vengeance, such that violence was greater among aggressive drivers, but only for those with elevated levels of vengeance.

Comparative metabolism of chrysene and 5-methylchrysene by rat and rainbow trout liver microsomes.

We have investigated the metabolism of chrysene (CHR) and 5-methychyrsene (5-MeCHR) by Shasta rainbow trout (Oncorhyncus mykiss) and Long Evans rat liver microsomes to assess the effect of a non-benzo ring methyl substituent on the reactions involved in the metabolism of polycyclic aromatic hydrocarbons (PAHs). Trout as well as rat liver microsomes metabolized both CHR and 5-MeCHR at essentially similar rates, indicating that the methyl substituent does not alter the substrate specificity of the cytochrome P450(s) involved in the metabolism of the two PAHs. Dihydrodiols were the major CHR metabolites formed by both trout and rat liver microsomes, whereas the trout liver microsomes formed a considerably higher proportion of 5-MeCHR phenols compared to diols, indicating that 5-methyl substitution alters the substrate specificity of trout microsomal epoxide hydrolase for 5-MeCHR epoxides.

Metabolism of chrysene by brown bullhead liver microsomes.

We have investigated the regio- and stereoselective metabolism of chrysene, a four-ring symmetrical carcinogenic polycyclic aromatic hydrocarbon (PAH), by the liver microsomes of brown bullhead (Ameriurus nebulosus), a bottom-dwelling fish species. The liver microsomes from untreated and 3-methylcholanthrene (3-MC)-treated brown bullheads metabolized chrysene at the rate of 30.1 and 82.

Synthesis of dihydrodiol metabolites implicated in the mechanism of carcinogenesis of phenanthro[4,3-b][1]benzothiophene and phenanthro[3,4-b][1]benzothiophene, the polycyclic sulfur heterocycles with a "Fjord" structure.

Dihydrodiols, which are potential proximate carcinogens of phenanthro[4,3-b][1]benzothiophene (3) and phenanthro[3,4-b][1]benzothiophene (4) and possess a "fjord" structure, were synthesized. The dihydrodiols synthesized were trans-3,4-dihydroxy-3,4-dihydrophenanthro[4,3-b][1]benzothiophene (5) and trans-3,4-dihydroxy-3,4-dihydrophenanthro[3,4-b][1]benzothiophene (6). The precursors to the dihydrodiols 5 and 6 were 3-methoxyphenanthro[4,3-b][1]benzothiophene (11) and 3-methoxyphenanthro[3,4-b][1]benzothiophene (16).

Courtesy stigma in mothers of children with Attention-Deficit/Hyperactivity Disorder: a preliminary investigation.

Mothers of children with Attention-Deficit/Hyperactivity Disorder face an increased risk for depression, anxiety, and social isolation. In addition to stress due to children's behavior, mothers of children with ADHD may also feel stigmatized by their children's diagnosis. Fifty-one mothers participated in a study to assess attitudes toward ADHD.

The Effects of Alcohol in Breast Milk on Infant Behavioral State and Mother-Infant Feeding Interactions.

The short-term impact of infant exposure to alcohol in breast milk on mother-infant interactions and infant arousal was examined. Fourteen mother-infant dyads were tested on 2 occasions that consisted of an alcohol administration and a nonalcohol condition. Mother-infant interactions during feeding were videotaped and coded for dyadic reciprocity, maternal noncontingency, and dyadic conflict.

Evidence for an association between gender-role identity and a measure of executive function.

Two studies assessed the relation between gender role and executive function. In Study One (N = 234) analyses indicated that among college students executive function, assessed by the Coolidge and Griego scale, is related to masculine gender-role classification, measured by the Bem Sex-role Inventory. This relationship remained significant when biological sex was controlled.

A New and Concise Synthesis of 3-Hydroxybenzo[c]phenanthrene and 12-Hydroxybenzo[g]chrysene, Useful Intermediates for the Synthesis of Fjord-Region Diol Epoxides of Benzo[c]phenanthrene and Benzo[g]chrysene.

A new strategy which involves a palladium-catalyzed cross-coupling reaction has been developed for the rapid synthesis of 3-hydroxybenzo[c]phenanthrene (5) and 12-hydroxybenzo[g]chrysene (6). These phenolic compounds are the key intermediates for the synthesis of highly carcinogenic fjord-region diol epoxide metabolites 3 and 4 of benzo[c]phenanthrene (1) and benzo[g]chrysene (2). The cross-coupling reaction of 2-bromo-5-methoxybenzaldehyde (9) with naphthalene-1-boronic acid (7) and phenanthrene-9-boronic acid (8) produced 2-(1-naphthyl)-5-methoxybenzaldehyde (10) and 2-(9-phenanthryl)-5-methoxybenzaldehyde (11), respectively, in quantitative yields.

Relations Between Women's Depressive Symptoms and Perceptions of Infant Distress Signals Varying in Pitch.

Fifteen nondepressed, 15 moderately depressed, and 15 severely depressed women rated tape-recordings of a newborn infant's hunger cry digitally altered to increase in fundamental frequency in 100 Hz increments. Cries were rated on 4 perceptual (e.g.

Relation Between Maternal Cigarette Smoking During Pregnancy and Behavioral and Physiological Measures of Autonomic Regulation in Neonates.

The effects of maternal cigarette smoking during pregnancy on behavioral and physiological measures of arousal were examined in a sample of 50 neonates. After the effects of alcohol, caffeine, and maternal demographic variables were statistically controlled, regression analyses showed that maternal smoking during pregnancy was predictive of higher heart rates overall and during quiet and active sleep. Maternal smoking during pregnancy was also predictive of lower heart rate variability and an increased number of tremors and changes in behavioral state.

Evidence for anomalous lateralization across domain in ADHD children as well as adults identified with the Wender Utah rating scale.

Two studies assessed the relation between ADHD symptomatology and correlates of cerebral dominance. In the first, laterality was examined in school children (N=57), 28 with ADHD. Parental reports of greater attentional symptoms were related to non-righthandedness, but teacher reports were related to anomalous laterality of foot, ear and eye, as well as hand.

Metabolism of benzo(a)pyrene by duck liver microsomes.

The metabolism of benzo(a)pyrene [BP], a model carcinogenic PAH, by hepatic microsomes of two duck species, mallard (Anas platyrhynchos) and common merganser (Mergus merganser americanus) collected from chemically-contaminated and relatively non-contaminated areas was investigated. The rate of metabolism of BP by liver microsomes of common merganser and mallard collected from polluted areas (2,650 +/- 310 and 2,200 +/- 310 pmol/min per mg microsomal protein, respectively) was significantly higher than that obtained with liver microsomes of the two species collected from non-polluted areas (334 +/- 33 and 231 +/- 30 pmol/min per mg microsomal protein, respectively). The level of cytochrome P-450 1A1 was significantly higher in the liver microsomes of both duck species from the polluted areas as compared to the ducks from the non-polluted areas.

The hsp110 and Grp1 70 stress proteins: newly recognized relatives of the Hsp70s.

Both the Grp170 and Hsp110 families represent relatively conserved and distinct sets of stress proteins, within a more diverse category that also includes the Hsp70s. All of these families are found in a wide variety of organisms from yeasts to humans. Although Hsp110s or Grp170s are not Hsp70s any more than Hsp70s are Hsp110s or Grp170s, it is still reasonable to refer to this combination of related families as the Hsp70 superfamily based on arguments discussed above and since no obvious prokaryotic Hsp110 or Grp170 has yet been identified.

Population dynamics of Aeromonas spp. in an urban river watershed.

Density of Aeromonas spp. at one site in the Buffalo River and at four sites on its upstream tributaries was followed from June 1992-June 1993. Membrane filtration counts of Aeromonas during the summer ranged between 18 and 4000 ml-1, which were one to two logs higher than faecal coliform and faecal streptococci densities.

Acoustic characteristics of children who speak Arabic.

The vocal characteristics of mean fundamental frequency, jitter, shimmer, harmonics-to-noise ratio, and breathiness were analyzed in 110 (F = 54, M = 56) Arabic-speaking children. The subjects were from Amman, Jordan, ranging in age from 5 to 20 years. Each subject was tape recorded during the production of the vowels /a/ and /i/.