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Cancer of the blood continues to be a major mortality factor globally. Arylidene compounds are well known for their anticancer effects. Here we describe the biological efficacy of IOX-101, a potential lead-compound of arylidene in acute myeloid leukemia (AML). Initially, molecular docking analysis was performed to check the binding efficacy of the compound with protein kinase B (Akt). The ability of the molecule to inhibit AML proliferation was assessed in THP-1 and Kasumi-6 cells by a standard MTT assay. Hoechst 333258/propidium iodide (PI) staining was carried out to analyze the nuclear damage. Flow cytometry was performed to check the apoptotic and cell cycle changes in THP-1 cells. The effect of IOX-101 on Akt phosphorylation was assessed by Western blot analysis. Molecular docking revealed interaction and binding of IOX-101 with the active site of Akt enzyme. The compound reduced proliferation of both AML cell lines in a dose-responsive way. Nuclear staining and cell cycle results revealed DNA damage by IOX-101 in THP-1 cells, and a significant increase in early and late phase apoptotic cells. A dose-dependent dephosphorylation of Akt (Ser 473) by IOX-101 was observed, which indicated allosteric inhibition of Akt by the compound. Our results showed that the DNA damage-mediated antiproliferative effect of IOX-101 in AML cells was mediated by Akt enzyme inhibition, and that this molecule possesses an effective chemotherapeutic potential against AML.

In the presence of an iodinated contrast medium, X-ray absorption is enhanced owing to photoelectric interactions. This has been shown both experimentally and in patients undergoing radiographic procedures using contrast media (Adams et al, 1977; Norman et al, 1978; Callisen et al, 1979; Cockran et al, 1980; Matsudaira et al, 1980; Matsubara et al, 1982). Chromosome aberration assays of circulating lymphocytes in these patients revealed a significant increase in absorbed dose compared with those who underwent a similar radiological procedure without the use of contrast media. This effect is most significant at X-ray energy levels just above the binding energy of iodine K electrons. Ejected photoelectrons are estimated to deposit their energy within a few micrometers in tissue (Cole, 1969). In angiography, an iodine contrast medium is irradiated in small blood vessels so that attenuation and “hardening” of X rays are unlikely to be significant. However, when a larger volume of tissue is irradiated in the presence of a contrast medium, the X rays become not only attenuated but also “hardened” as they travel through the iodine-containing tissue. In contrast to the incident X rays, the exit X rays are predicted to be less effective in eliciting photoelectric interactions because of the reduction in the “soft” component of the X-ray spectrum. In this communication we report measurements of the dose enhancement as a function of iodine concentration and the effect of X-ray hardening on the photoactivation using biological dosimetry based on cell survival.

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Background: Rumex nervosus is a plant found and used in Saudi Arabia as traditional herbal medicine. Various types of plant extracts with inherent synergistic properties are being used against oral diseases. Thus, in the present study, the anti-microbial activity of Rumex nervosus extracts was studied against six common oral pathogenic bacterial strains and a pathogenic fungus. Materials and Method: Plants of R. nervosus were collected and air-dried, and extracts from various plant parts were obtained. Six clinical isolates of bacteria, namely Staphylococcus aureus, Streptococcus mutans, S. salivarius, S. sanguis, E. faecalis , and Lactobacillus acidophilus ), and one pathogenic Candida ( C. albicans ) were obtained. Antibacterial and antifungal activity of R. nervosus was determined using the Kirby–Bauer agar disc diffusion method. Zones of inhibition were recorded after 48 h of incubation. Data collected were analyzed. A two-way analysis of variance (ANOVA) was applied. P < 0.05 was considered statistically significant. Results: Methanol extract from leaves were highly effective against S. aureus , with a mean inhibition zone of 33 mm, followed by a 28-mm zone of inhibition using an extract from roots and a minimum inhibition zone using an extract from stems. Zones of inhibition using methanol extract from roots were effective against S. mutans , S. sanguinis , E. faecalis , and L. acidophilus , with mean inhibition zones being 19, 17, 33, and 31 mm, respectively. Conclusion: The study has provided insight into a new potential herbal anti-microbial agent that may benefit dental care.

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,. Effect of negative pions on the proliferative capacity of ascites tumor cells (lymphoma) in vivo.' Radiation Res.pp.-, _ I - ABSTRACTWe have attempted t o determine the relative biological effective -.ness (RBE) of negative pions in the Bragg-peak region as compared t o the plateau region and to gamma rays. We irradiated LAF1 mice, bearing 5-day-old lymphoma ascites tumors, in the peak and plateau regions of a cobalt-60 gamrna rays. We calculated peak doses from those at the plateau, using a measured average peak-to-plateau ionization ratio of 1.5.' Doses in the plateau region rangedfrom 145 to 250 rads; doses in the peak region ranged f r o m 220 to 380 rads. The survival curve for cells irradiated in the peak region gave a Do of 65 f 15 rads. The plateau points were not reliable. , A replicate experiment was performed using Coao y-rays, yieldinga survival-curve Do of 350 f 50 rads. a n RBE of 5.4 * 1.8 is obtained for negative pions in the peak region, based . .

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