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Novel derivatives of the potent human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) inhibitor TSAO-T have been designed, synthesized and tested for their in vitro antiretro-viral activity against HIV. These TSAO-T derivatives have been designed as potential bidentate inhibitors of HIV-1 RT, which combine in their structure the functionality of a non-nucleoside RT inhibitor (TSAO-T) and a bivalent ion-chelating moiety (a β-diketone moiety) linked through an appropriate spacer to the N-3 of thymine of TSAO-T . Some of the new compounds have an anti-HIV-1 activity comparable to that of the parent compound TSAO-T, but display a markedly increased antiviral selectivity. There was a clear relationship between antiviral activity and the length of the spacer group that links the TSAO molecule with the chelating moiety. A shorter spacer invariably resulted in increased antiviral potency. None of the TSAO-T derivatives were endowed with anti-HIV-2 activity.

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

At present more than 70 human papillomaviruses (HPV) genotypes have been described and each shows a predilection for a cutaneous or mucosal surface. There is a strong association between infection with specific genital viruses (i.e., types 16 and 18) and the development of cervical cancer. Thus, intervention with the natural history of HPV infection in the genital tract may form the basis for an effective anticancer strategy. We have shown that treatment of cell lines derived from human cervical carcinomas [i.e., SiHa and CaSki (HPV-16-positive)] and HeLa (HPV-18-positive)] with HPMPC (cidofovir) results in a concentration- and time-dependent inhibition of cell proliferation. We report here the effects of HPMPC on the growth of cervical carcinoma (SiHa) xenografts in athymic nude mice. Athymic mice between the age of 6 and 8 weeks were injected SC with 5 to 10x10(6) cells. Once tumors were established, the mice were injected with PBS (placebo), HPMPC, or cytarabine (AraC) at the tumor site. Animals that were injected intratumorally with HPMPC at a dose of 5 mg/ml (0.25 mg/injection) or 10 mg/ml (0.5 mg/injection) three or five times per week, once daily, during 4 weeks showed a statistically significant reduction in tumor size compared to the placebo group or AraC group. However, when HMPC was administered topically (as a cream) or systemically (intraperitoneally), no reduction of tumor growth was observed at nontoxic concentrations, suggesting that a high local concentration of HPMPC is required to achieve a significant decrease of tumor growth.

Selective laser melting (SLM) is a layer-wise material additive process for the direct fabrication of functional metallic parts. During the process, successive layers of metal powder are fully molten and consolidated on top of each other by the energy of a high intensity laser beam. The process is capable of producing almost fully dense three-dimensional parts having mechanical properties comparable to those of bulk materials. However, one of the problems encountered in SLM process is the occurrence of elevated ridges of the solidified material at the edges of the successive layers. Those ridges reduce the dimensional accuracy and topology of the top surface. The edge-effect problem is encountered not only in SLM, but also in other production techniques applying melting processes such as LENS® (The Laser Engineered Net Shaping) and EBM (Electron Beam Melting). In this study, the reasons for elevated edges and solutions to this problem are investigated and reported. Different scan strategies as well as different hatching and contour parameters are tested to reduce the edge-effect problem. Besides, the influence of applying laser re-melting in combination to selective laser melting has been investigated. It turns out that re-melting layers deposited by SLM improves the part density and surface roughness, but creates on its own elevated edges.

Activity profiles of the products may contribute considerably to future drug-discovery studies.

Respiratory papillomatosis is a rare and often severe disease, usually localized in the larynx. It may cause respiratory distress and even life-threatening obstruction of the airways. Treatment is generally based on the evaporation of the lesions with a CO2 laser, but microsurgery, cytotoxic and/or cytostatic drugs, interferons, and vaccines are also used. Cidofovir [(S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine] (HPMPC) was shown to suppress the growth of tumors induced by rabbit papillomavirus as well as human papillomavirus (HPV). The efficacy of cidofovir was assessed in 17 patients with severe respiratory papillomatosis. Cidofovir at a concentration of 2.5 mg/ml was injected directly in the different laryngeal papillomatous lesions during microlaryngoscopy under general anesthesia. Biopsies were taken before the treatment was started both for anatomopathology and viral typing. HPMPC kinetics in serum was monitored in three patients, the drug levels being determined by high-performance liquid chromatography. Complete disappearance of the papillomatosis was observed in 14 patients. Four patients relapsed and were successfully treated again with cidofovir. Of the three remaining patients, one progressed while under treatment with cidofovir, after an initial marked response. One patient had a partial remission and remained stable for more than 1 year after the last injection. He had a very aggressive and extensive disease originally. Finally, one patient was lost to follow-up after four injections. Intratumoral injections of cidofovir for the treatment of severe laryngeal papillomatosis is a powerful new therapeutic approach for this disease. Treatment was well tolerated, and no significant side effects were noted.

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Atomic clocks based on coherent population trapping and constructive polarization modulation are promising for high performance and compact devices. We have demonstrated a cw mode CPT clock with a short-term fractional frequency stability at the level of 3. \pmb2×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-13</sup> /√{τ} for a few 100 s integration time. This Double-Modulation CPT technology can be reduced to a miniature and robust setup due to its linear architecture. This clock could find future applications in industry, telecommunications, instrumentation, or global navigation satellite systems.

A chemically synthesized lipid A subunit analogue, GLA-60 (2-deoxy-4-O-phosphono-2-[(3R)-3-hydroxytetradecanamido]-3-O-[(3R) - 3-tetradecanoyloxytetradecanoyl]-D-glucose), has many of the activities of endotoxins but little, if any, toxicity. We investigated the protective activity of GLA-60 against murine cytomegalovirus (MCMV) infection in NMRI mice. Intraperitoneal administration of GLA-60 at 1 day before MCMV infection at doses of 1, 10, or 100 micrograms per mouse significantly reduced mortality. GLA-60 stimulated peritoneal natural killer (NK) cell and macrophage activities, and these activities were abolished by in vitro treatment with anti-asialo GM1 antibody and anti-Mac1 antibody, respectively. GLA-60 proved also protective against MCMV infection in mice in which either NK cells or macrophages were depleted by in vivo treatment with anti-asialo GM1 or anti-Mac1 antibody. The anti-MCMV activity of GLA-60 can at least be partially attributed to activation of NK cells and macrophages.

Non-steroidal anti-inflammatory drugs (NSAID) pharmacophores are interesting in designing potential anticancer drugs. Indeed, numerous experimental, epidemiologic and clinical studies suggest that NSAIDs are promising anticancer drugs. Herein, NSAID hydroxamic acids 3a-i were prepared by a new synthetic procedure and evaluated for their antiviral and cytostatic activity against malignant tumor cell lines and normal human fibroblasts (WI38). Antiviral activity evaluation results indicated that 3f had only a minor activity against the influenza virus A/H1N1 subtype with a selectivity index of 7-10. On the other hand, the results of the in vitro cytostatic activity evaluations revealed that the majority of NSAID hydroxamic acid derivatives 3a-i exhibited a strong non-specific antiproliferative effect at the highest concentration (100 microM) on the tested cell line panel. Only compounds 3b, 3e and 3i exerted a differential dose-dependent inhibitory activity against the growth of HeLa cells (p < 0.05) at concentration 10 microM. Among those three compounds, only compound 3b showed a selective cytostatic effect on HeLa in comparison with normal fibroblasts.