Efficacy and safety of a novel acetylcholinesterase inhibitor octohydroaminoacridine in mild-to-moderate Alzheimer's disease: a Phase II multicenter randomised controlled trial.

Background: inhibition of acetylcholinesterase (AChE) has been a effective treatment for Alzheimer's disease (AD). Octohydroaminoacridine, a new AChE inhibitor, is a potential treatment for AD. Method: we conducted a multicenter, randomised, double blind, placebo-controlled, parallel-group Phase II clinical trial to investigate the effects of octohydroaminoacridine in patients with mild-to-moderate AD. Patients were randomised to receive placebo thrice daily, octohydroaminoacridine 1 mg/thrice daily (TID) (low-dose group), 2 mg/TID (middle-dose group) or 4 mg/TID (high-dose group). Doses in the middle-dose and high-dose group were titrated over 2-4 weeks. Changes from baseline to Week 16 were assessed with the AD Assessment Scale-Cognitive Subscale (ADAS-cog), Clinician's Interview-Based Impression of Change Plus (CIBIC+), activities of daily living (ADL) and the neuropsychiatric inventory (NPI). ADAS-cog was the primary end point of the study. A two-way analysis of covariance and least squares mean t-test were used. Results: at Week 16, the changes from baseline in ADAS-cog were 1.4, -2.1, -2.2 and -4.2 for placebo, low-, middle- and high-dose groups, respectively. Patients in the high-dose group had better performance in CIBIC+ and ADL scores at the end of the study. There was no significant difference in the change in NPI score among the groups. The effects of octohydroaminoacridine were dose dependent, and were effective within 16 weeks of treatment. No evidence was found for more adverse events that occurred in different drug groups than placebo group. Conclusions: octohydroaminoacridine significantly improved cognitive function and behaviour in patients with mild-to-moderate AD and this effect was dose dependent.

Magnetic Field-Induced Accentuation of Drug Release from Core/Shell Magnetic Mesoporous Silica Nanoparticles for Anticancer Treatment.

Drug (9-aminoacridine) loaded core/shell magnetic iron oxide-containing mesoporous silica nanoparticles (MMSN) were treated with HeLa cells and the drug carriers were agitated by expo- sure to magnetic field. Viability studies show the applicability of drug loaded magnetic material for anticancer treatment, which is enhanced upon stimulation with magnetic field. Confocal micrographs of fluorescein grafted MMSN-treated HeLa cells confirmed the ability of magnetic field to concentrate the synthesized material in the exposed area of the cells. The synthesized material and the applied drug delivery method may find application in magnetic field-responsive targeted treatment of cancer.

Decreasing the thresholds for electroporation by sensitizing cells with local cationic anesthetics and substances that decrease the surface negative electric charge.

The recently described method of cell electroporation by flow of cell suspension through localized direct current electric fields (dcEFs) was applied to identify non-toxic substances that could sensitize cells to external electric fields. We found that local cationic anesthetics such as procaine, lidocaine and tetracaine greatly facilitated the electroporation of AT2 rat prostate carcinoma cells and human skin fibroblasts (HSF). This manifested as a 50% reduction in the strength of the electric field required to induce cell death by irreversible electroporation or to introduce fluorescent dyes such as calcein, carboxyfluorescein or Lucifer yellow into the cells. A similar decrease in the electric field thresholds for irreversible and reversible cell electroporation was observed when the cells were exposed to the electric field in the presence of the non-toxic cationic dyes 9-aminoacridine (9-AAA) or toluidine blue. Identifying non-toxic, reversibly acting cell sensitizers may facilitate cancer tissue ablation and help introduce therapeutic or diagnostic substances into the cells and tissues.

Studies on the inclusion behavior of 9-Aminoacridine into cyclodextrins: spectroscopic and theoretical evidences.

9-Aminoacridine (9-AA) is an important attractive pharmaceutical drug employed as chemotheraptic agent for wound dressings. However, 9-AA possesses limited solubility and rapid metabolic decomposition renders this potential drug to limit its applications. Here we propose cyclodextrins (CDs) as a drug carrier to improve the bioavailability, solubility of 9-AA. The interaction between 9-AA and CDs (α-CD and ß-CD) has been studied using UV-Vis absorption, steady state time resolved fluorescence, (1)H NMR and FT-IR spectroscopy techniques. The spectroscopic measurements show that 9-AA does not form stable complex with α-CD and also confirmed by DFT calculations. On the other hand, 9-AA forms inclusion complex with ß-CD in a 1:1 stoichiometry ratio. Our DFT results suggest that 9-AA stabilizes inside the CD environment through hydrogen bonding that has unambiguously confirmed by AIM analysis. Thus our studies provide a useful insights in the development of Aminoacridine based drugs & its delivery through a suitable carrier like CDs.

Frameshift mutations produced by 9-aminoacridine in wild-type, uvrA and recA strains of Escherichia coli; specificity within a hotspot.

The endogenous tonB gene of Escherichia coli was used as a target for 9-aminoacridine-induced mutations that were identified in recA(-) and uvrA(-) cells. The cytotoxicity of 9-aminoacridine was enhanced in the uvrA and recA strains compared to the wild-type strain, and the mutagenicity of 9-aminoacridine in the uvrA and recA strains was similar to that in the wild type. For all three strains, the most common mutations were minus frameshifts in repetitive G:C base-pairs followed by minus frameshifts in nonrepetitive G:C base-pairs. 9-aminoacridine-induced minus frameshifts in the wild-type strain were distributed with several hot and warm spots. These sites were also hot and warm spots for minus frameshifts in the recA and uvrA stains. Furthermore, they were hot and warm sites in a 9-aminoacridine-treated strain carrying the target tonB gene oriented in the opposite direction. 9-Aminoacridine is known to interact with DNA to form intercalations which are involved in minus frameshift mutagenesis. In this study, we therefore argue that 1) 9-aminoacridine can induce bulky DNA lesions which are excised by nucleotide excision repair and not involved in mutagenesis, 2) the presence or absence of a recA-dependent repair pathway does not influence the mutagenic effect of 9-aminoacridine, and 3) both leading strand and lagging strand replication equally produce minus frameshifts, therefore gene orientation is not an important determinant of the formation of hot and warm spots by 9-aminoacridine.

Multicenter comparison of clotrimazole vaginal tablets, oral metronidazole, and vaginal suppositories containing sulfanilamide, aminacrine hydrochloride, and allantoin in the treatment of symptomatic trichomoniasis.

BACKGROUND AND OBJECTIVES: Trichomonas vaginalis is a common vaginal pathogen. Oral metronidazole is the drug of choice for the treatment of trichomoniasis. Oral metronidazole, however, may cause unpleasant side effects and is contraindicated during the first trimester of pregnancy. In vitro studies and preliminary clinical data have suggested that intravaginal clotrimazole may be effective against this pathogen. GOALS: To compare the efficacy of clotrimazole vaginal tablets, oral metronidazole, and vaginal suppositories containing sulfanilamide, aminacrine, and allantoin (AVC suppositories) in the treatment of women with symptomatic trichomoniasis. STUDY DESIGN: In a multicenter, open-label trial conducted in 1982 and 1983, 168 symptomatic women with microscopically evident vaginal trichomoniasis were randomized to receive any of 2 g of metronidazole as a single oral dose, two 100-mg clotrimazole vaginal tablets once a day for 7 days, or vaginal suppositories containing 1.05 g of sulfanilamide, 14 mg of aminacrine hydrochloride, and 140 mg of allantoin (AVC suppositories) twice a day for 7 days. Wet mounts and cultures were repated at 1 to 2 and 4 to 6 weeks after completion of treatment. RESULTS: The number of patients who had positive cultures after treatment were 40/45 (88.9%) in the clotrimazole group, 35/43 (81.4%) in the AVC suppository group, and 9/45 (20%) in the metronidazole group (P < 0.001). All treatments were associated with a reduction in reported symptoms. Oral metrohidazole was more effective in reducing symptoms than either of the topical preparations. Adverse events, mostly mild or moderate in severity, were reported by 7 (14.6%) of 48 patients who had received oral metronidazole and 4 (7.8%) of 51 women who used AVC suppositories. There were no adverse events reported by the 50 women who used clotrimazole vaginal tablets. CONCLUSIONS: Oral metronidazole was more effective in eradicating T. vaginalis than clotrimazole vaginal tablets or AVC vaginal suppositories. All three regimens reduced symptoms; oral metronidazole was more effective in reducing symptoms than either topical preparation.

Synergism and antagonism between N-methyl-N'-nitro-N-nitroso-guanidine and 9-aminoacridine in mutation induction in Escherichia coli K12.

When bacteria were treated simultaneously with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and low concentrations of 9-aminoacridine (9AA), the yield of frameshift mutations was much greater than that expected on the basis of independent action of both mutagens. In combination with a high concentration of 9AA, however, MNNG had an antagonistic effect upon the induction of frameshift mutations. There was no synergistic interaction between the two mutagens in bacteria in which the adaptive response to methylating agents had been induced. 9AA not only induced frameshift mutations, but also caused a small increase in reversions of a nonsense (ochre) mutation and, in combination with low MNNG concentrations, it had a small synergistic effect.

Acute monocytic leukaemia in adults: treatment and prognosis in 99 cases.

Acute monocytic leukaemia (AMoL) was diagnosed in 99 adults, aged 18-85 years (median 56) over a period of 10 years. Sixty-five patients had extramedullary leukaemia, 13 had clinical signs of leucostasis, and 19 had disseminated intravascular coagulation. Four patients died before receiving any treatment, 12 received supportive care only and seven received low dose AraC, but only one of them responded. Seventy-six patients received intensive chemotherapy, 72 of them with an anthracycline-AraC based regimen, with or without an epipodophyllotoxin. Fifteen patients died within 7 d of diagnosis, due to leucostasis in nine cases. Predictive factors for early death were advanced age, leucostasis, fever, leucocytes above 100 x 10(9)/l, and renal failure. Fifty (66%) of the patients treated intensively reached complete remission (CR). Advanced age, fever and complex cytogenetic abnormalities were significantly associated with a lower CR rate. Median actuarial disease-free survival was 20.5 months, and was not significantly influenced by any pretreatment parameter. Five patients relapsed in the central nervous system (CNS), in spite of systematic CNS prophylaxis. No differences in CR rates were seen with the three anthracycline-AraC based regimens used in our patients. Significant differences in disease-free survival were seen between them, however, suggesting that early consolidation chemotherapy and, more hypothetically, epipodophyllotoxin agents could prolong remission duration in AMoL.

Enzymatic amplification of translation inhibition of rabbit beta-globin mRNA mediated by anti-messenger oligodeoxynucleotides covalently linked to intercalating agents.

The effects of anti-messenger oligodeoxynucleotides, covalently linked to an intercalating agent, on translation of rabbit beta-globin mRNA, were investigated both in wheat germ extract and in microinjected Xenopus oocytes. A specific inhibition of beta-globin synthesis was observed in both expression systems with a modified 11-mer covalently linked to an acridine derivative. In injected oocytes a more efficient block was observed with this modified oligonucleotide than with its unsubstituted homolog. This was ascribed to stacking interactions of the intercalating agent with base pairs which provide an additional stabilization of the [mRNA/DNA] hybrid. We demonstrated that in wheat germ extract, the modified and unmodified oligonucleotides behaved similarly due to the presence of a high RNaseH activity. RNaseH was also present, although to a lesser extent, in the oocyte cytoplasm. This anti-messenger DNA-induced degradation of target mRNA resulted in amplified efficiency of hybrid-arrested translation. This additional mechanism might provide anti-sense DNAs with an advantage over anti-sense RNAs.

Effect of antimicrobial agents on root surface caries, alveolar bone loss, and microflora in rice rats.

Two antimicrobial agents, 9-aminoacridine (0.2%) and minocycline (0.2%), were evaluated for their efficacy in inhibiting root surface caries, bone loss, and microflora in rice rats. A solution of 5000 ppm fluoride was used as a positive control for the inhibition of root surface caries, and double-distilled water was used as a negative control group. Each rat was treated by having its molar teeth swabbed 2 X per day with the prescribed agent in its group for nine weeks. Root caries reduction in the minocycline and fluoride groups was not significantly different, but the reduction was significantly greater than in the 9-aminoacridine group, with the caries score in all three groups being significantly less than that in the water control. Bone loss reduction for the minocycline group was significantly greater than that for any other group.

Preclinical pharmacologic investigations on a new group of acridine derivatives with oncostatic activity. I. Acute and subchronic action.

The influence of l-nitro-9-/2-dihydroxyethylamino-ethylamino-/-acridine (C-835) and l-nitro-9/3-izopropylaminopropylamino/-acridine (C-846) on the basic functions of animal organism in acute and subchronic experiments was studied. Both compounds displayed distinct all-biologic activity. Their toxicity (LD50) in mice was contained in milligramme interval (i.v.), while LD50 administered into the stomach was several dozen times higher. Even administration in protective phosphate buffer, which provides the most neutral pH, produced quite strong local irritant action. The range between LD50 and LD10 was relatively small, which proved relatively small tolerance factor. Both preparations injected intravenously in the doses starting from several mg/kg had hypotensic influence due to their affinity with the myocardium, the parasymphatetic system and the vascular system. The preparations acted spasmolytically on intestine muscles both in vivo and in vitro in a number of animal species. Central action showed clear stimulating component in a behavioric test. The effect of the compounds in interaction to hypnotic and convulsant drugs was equivocal and dependent on the dose and the reference-preparation. The examined compounds did not influence reproduction processes and did not display the teratogenic action. They impaired only the speed of growth of the newborns. The effect of both examined compounds was qualitatively and quantitatively similar.

Preclinical pharmacologic investigations on a new group of acridine derivatives with oncostatic activity. II. Chronic action.

Influence of 1-nitro-9-(2-dihydroxyethylaminoethylamino)-acridines (C-835) and 1-nitro-9-(3-isopropylamino-propylamino)-acridines (C-846) on animal organs and their basic functions was studied in the chronic action. Rabbits responded to the drugs with considerable tolerance which was less manifested in rats. Slight toxic effect was observed only after maximal doses with which the animals survived 3-month exposure. Enzyme studies and creatinine clearance test did not show any clear-cut impairment of hepatic and renal function. Neither did the preparations influence the red and white blood system, nor the blood clotting time. Microscopic examinations showed their slight (initially) morphologic changes which later passed into degenerative changes (liver, kidney, myocardium) as well as typical of oncostatics, changes in intestinal villi, nuclei and lymphatic system. Also desquamation of intestinal epithelium, hypertrophy of their lamina propria, impairment of spermato- and spermiogenesis as well as atrophy of lymphatic germinal centers and decreased number of small lymphocytes in lymph nodes and spleen were noted. Deviation between the results of function and morphologic tests were discussed. Microscopic changes observed after treatment of the tested acridine derivatives were considered too small to damage the particular organs function.