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The futility of the debate between heredity and environment as determinants of intelligence is argued, with convictions inspired by C. Burt's work (apart from the question of fraud in his work). It is contended that the influence of this misconceived ideological disagreement is apparent in today's educational systems. (SLD)

The efficiency of N-(4-tert-butylbenzoyl)-2-hydroxy-1-naphthaldehyde hydrazone (BBNH) in inhibiting the catalytic activity of HIV-1 reverse transcriptase (RT) was analyzed during HIV-1 replication in vitro. The administration of BBNH inhibited the RNA-dependent DNA polymerase, DNA-dependent DNA polymerase and ribonuclease H activities of HIV-1 RT in vitro. Furthermore, non-nucleoside inhibitor-resistant mutant HIV-1 RT activity and viral replication in infected cells were also inhibited by the hydrazone.

The combination of UC38 and UC84 shows a high degree of synergy in inhibiting HIV-1 replication in both MT-4 and cord mononuclear cells and are the first example of synergistic inhibition of HIV-1 RT by combinations of nonnucleoside inhibitors. This effect is noted primarily in reactions containing high concentrations of primer/template and Km levels of dNTP substrate and is independent of both primer/template identity and the molar ratio of UC84:UC38. A notable synergy in the inhibition of RT activity is indicated by the combination indices which are in the range of 0.4-0.6.

Two non-nucleoside inhibitors of the HIV reverse transcriptase (RT) enzyme bind to different forms of the enzyme-substrate complex. Oxathiin carboxanilide (UC84) and a second-generation thiocarboxanilide (UC38) can inhibit HIV-1 RT in vitro. UC84 binds to the free enzyme and the enzyme-primer/template (P/T) complex, but not to the enzyme-P/T-dNTP complex. UC38 binds to the enzyme-P/T-dNTP complex but not to the free enzyme or the enzyme-P/T complex.

Abstract Background A variety of mint [Mentha spicata] has been bred which over-expresses Rosmarinic acid (RA) by approximately 20-fold. RA has demonstrated significant anti-inflammatory activity in vitro and in small rodents; thus it was hypothesized that this plant would demonstrate significant anti-inflammatory activity in vitro. The objectives of this study were: a) to develop an in vitro extraction procedure which mimics digestion and hepatic metabolism, b) to compare anti-inflammatory properties of High-Rosmarinic-Acid Mentha spicata (HRAM) with wild-type control M. spicata (CM), and c) to quantify the relative contributions of RA and three of its hepatic metabolites [ferulic acid (FA), caffeic acid (CA), coumaric acid (CO)] to anti-inflammatory activity of HRAM. Methods HRAM and CM were incubated in simulated gastric and intestinal fluid, liver microsomes (from male rat) and NADPH. Concentrations of RA, CA, CO, and FA in simulated digest of HRAM (HRAMsim) and CM (CMsim) were determined (HPLC) and compared with concentrations in aqueous extracts of HRAM and CM. Cartilage explants (porcine) were cultured with LPS (0 or 3 μg/mL) and test article [HRAMsim (0, 8, 40, 80, 240, or 400 μg/mL), or CMsim (0, 1, 5 or 10 mg/mL), or RA (0.640 μg/mL), or CA (0.384 μg/mL), or CO (0.057 μg/mL) or FA (0.038 μg/mL)] for 96 h. Media samples were analyzed for prostaglandin E2 (PGE2), interleukin 1β (IL-1), glycosaminoglycan (GAG), nitric oxide (NO) and cell viability (differential live-dead cell staining). Results RA concentration of HRAMsim and CMsim was 49.3 and 0.4 μg/mL, respectively. CA, FA and CO were identified in HRAMsim but not in aqueous extract of HRAM. HRAMsim (≥ 8 μg/mL) inhibited LPS-induced PGE2 and NO; HRAMsim (≥ 80 μg/mL) inhibited LPS-induced GAG release. RA inhibited LPS-induced GAG release. No anti-inflammatory or chondroprotective effects of RA metabolites on cartilage explants were identified. Conclusions Our biological extraction procedure produces a substance which is similar in composition to post-hepatic products. HRAMsim is an effective inhibitor of LPS-induced inflammation in cartilage explants, and effects are primarily independent of RA. Further research is needed to identify bioactive phytochemical(s) in HRAMsim.

The article focuses on a study to examine the impact of the Keyes procedure in vitro on microbial agents related to periodontal disease. Researchers assessed the effect of the chemical agents, hydrogen peroxide and sodium bicarbonate, on the microbial flora of the periodontal pocket. The microbial agents were obtained from the American Type Culture Collection and grown in various media. Epithelial-like gingival cells were used to test the toxicity of the procedure on the microbial agents. The inhibitory concentrations of hydrogen peroxide for gingival cells seeded with mycoplasma salivarium were noted and it was concluded that the gingival cell viability varied with the number of cell layers.