20 research outputs found

    ArmAssist Robotic System versus Matched Conventional Therapy for Poststroke Upper Limb Rehabilitation: A Randomized Clinical Trial

    Get PDF
    The ArmAssist is a simple low-cost robotic system for upper limb motor training that combines known benefits of repetitive task-oriented training, greater intensity of practice, and less dependence on therapist assistance. The aim of this preliminary study was to compare the efficacy of ArmAssist (AA) robotic training against matched conventional arm training in subacute stroke subjects with moderate-to-severe upper limb impairment. Twenty-six subjects were enrolled within 3 months of stroke and randomly assigned to the AA group or Control group (n = 13 each). Both groups were trained 5 days per week for 3 weeks. The primary outcome measure was Fugl-Meyer Assessment-Upper Extremity (FMA-UE) motor score, and the secondary outcomes were Wolf Motor Function Test-Functional Ability Scale (WMFT-FAS) and Barthel index (BI). The AA group, in comparison to the Control group, showed significantly greater increases in FMA-UE score (18.0 +/- 9.4 versus 7.5 +/- 5.5, p = 0.002) and WMFT-FAS score (14.1 +/- 7.9 versus 6.7 +/- 7.8, p = 0.025) after 3 weeks of treatment, whereas the increase in BI was not significant (21.2 +/- 24.8 versus 13.1 +/- 10.7, p = 0.292). There were no adverse events. We conclude that arm training using the AA robotic device is safe and able to reduce motor deficits more effectively than matched conventional arm training in subacute phase of stroke.Andrej M. Savic and Milica S. Isakovic are employed at Tecnalia Serbia Ltd., Belgrade, Serbia, and Cristina Rodriguez-de-Pablo and Thierry Keller are employed at TECNALIA, San Sebastian, Spain, from which they receive financial compensation. No external support was received for conducting this study

    Distinct cytotoxic mechanisms of pristine versus hydroxylated fullerene

    Get PDF
    The mechanisms underlying the cytotoxic action of pure fullerene suspension (nano-C-60) and water-soluble polyhydroxylated fullerene [C-60(OH)(n)] were investigated. Crystal violet assay for cell viability demonstrated that nano-C-60 was at least three orders of magnitude more toxic than C-60(OH)(n) to mouse L929 fibrosarcoma, rat C6 glioma, and U251 human glioma cell lines. Flow cytometry analysis of cells stained with propidium iodide (PI), PI/annexin V-fluorescein isothiocyanate, or the redox-sensitive dye dihydrorhodamine revealed that nano-C-60 caused rapid (observable after few hours), reactive oxygen species (ROS)-associated necrosis characterized by cell membrane damage without DNA fragmentation. In contrast, C-60(OH)(n) caused delayed, ROS-independent cell death with characteristics of apoptosis, including DNA fragmentation and loss of cell membrane asymmetry in the absence of increased permeability. Accordingly, the antioxidant N-acetylcysteine protected the cell lines from nano-C-60 toxicity, but not C-60(OH)(n) toxicity, while the pan-caspase inhibitor z-VAD-fmk blocked C-60(OH)(n)-induced apoptosis, but not nano-C-60-mediated necrosis. Finally, C-60(OH)(n) antagonized, while nano-C-60 synergized with, the cytotoxic action of oxidative stress-inducing agents hydrogen peroxide and peroxynitrite donor 3-morpholinosydnonimine. Therefore, unlike polyhydroxylated C-60 that exerts mainly antioxidant/cytoprotective and only mild ROS-independent pro-apoptotic activity, pure crystalline C-60 seems to be endowed with strong pro-oxidant capacity responsible for the rapid necrotic cell death

    Isolation, Characterization, and In Vitro Cytotoxicity of New Sesquiterpenoids from Achillea clavennae

    Get PDF
    Further phytochemical investigation of the aerial parts of Achillea clavennae has resulted in the isolation of three new sesquiterpene lactones: two highly oxygenated germacranolides (1, 2) and the iso-seco-guaianolide 9(R)-acetoxy-3-O-methyl-iso-seco-tanapartholide (3). Eight known compounds were also found, of which 9-acetoxycanin (5), sintenin (6), and oleanolic acid (7) were detected for the first time. The structures of the isolated compounds were elucidated by combined spectroscopic methods (1D and 2DNMR, HRESIMS, CIMS, and FTIR). While the predominant metabolite germacranolide sintenin (6) was not cytotoxic, the new iso-seco-guaianolide (3) displayed cytotoxicity comparable to that of cisplatin and the lactone apressin (4), inducing partly apoptotic death in human U251 and rat C6 glioma cell lines

    Aloe emodin inhibits the cytotoxic action of tumor necrosis factor

    No full text
    We demonstrate the capacity of an herbal anthraquinone aloe emodin to reduce the cytotoxicity of the proinflammatory cytokine tumor necrosis factor (TNF) towards L929 mouse fibrosarcoma and U251 human glioma cell lines. Aloe emodin inhibited both TNF-induced cell necrosis and apoptosis, but it did not reduce cell death induced by UV radiation or hydrogen peroxide. Aloe emodin inhibited both basal and TNF-triggered activation of extracellular signal-regulated kinase (ERK), and a selective blockade of ERK activation mimicked the cytoprotective action of the drug. On the other hand, aloe emodin did not affect TNF-induced activation of p38 mitogen-activated protein kinase or generation of reactive oxygen species. The combination of aloe emodin and TNF caused an intracellular appearance of acidified autophagic vesicles, and the inhibition of autophagy with bafilomycin or 3-methyladenine efficiently blocked the cytoprotective action of aloe emodin. These data indicate that aloe emodin could prevent TNF-triggered cell death through mechanisms involving induction of autophagy and blockade of ERK activation. (C) 2007 Elsevier B.V. All rights reserved

    Antioxidative Activity of Diarylheptanoids from the Bark of Black Alder (Alnus glutinosa) and Their Interaction with Anticancer Drugs

    No full text
    Diarylheptanoids belong to polyphenols, a group of plant secondary metabolites with multiple biological properties. Many of them display antioxidative, cytotoxic, or anticancer actions and are increasingly recognized as potential therapeutic agents. The aim of this study was to evaluate antioxidant and cytoprotective activity of two diarylheptanoids: platyphylloside 5(S)-1,7-di(4-hydroxyphenyl)-3-heptanone-5-O-beta-D-glucopyranoside (1) and its newly discovered analog 5(S)-1,7-di(4-hydroxyphenyl)-5-O-beta-D-[6-(E-p-coumaroylglucopyranosyl)]heptane-3-one (2), both isolated from the bark of black alder (Alnus glutinosa). To that end, we have employed a cancer cell line (NCI-H460), normal human keratinocytes (HaCaT), and peripheral blood mononuclear cells. The effects on cell growth were assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide colorimetric assay. Cell death was examined by annexin V/propidium iodide staining on a flow cytometer. Reactive oxygen species production was examined by dihydroethidium staining. Mitochondrial structure and doxorubicin localization were visualized by fluorescent microscopy. Gene expression of manganese superoxide dismutase and hypoxia-inducible factor-1 alpha was determined by reverse transcription polymerase chain reaction. Diarylheptanoids antagonized the effects of either doxorubicin or cisplatin, significantly increasing their IC50 values in normal cells. Diarylheptanoid 1 induced the retention of doxorubicin in cytoplasm and reduced mitochondrial fragmentation associated with doxorubicin application. Diarylheptanoid 2 reduced the reactive oxygen species production induced by cisplatin. Both compounds increased the messenger ribonucleic acid expression of enzymes involved in reactive oxygen species elimination (manganese superoxide dismutase and hypoxia-inducible factor-1 alpha). These results indicate that neutralization of reactive oxygen species is an important mechanism of diarylheptanoid action, although these compounds exert a considerable anticancer effect. Therefore, these compounds may serve as protectors of normal cells during chemotherapy without significantly diminishing the effect of the applied chemotherapeutic.Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3677

    Dual antiglioma action of metformin: cell cycle arrest and mitochondria-dependent apoptosis

    No full text
    The present study reports for the first time a dual antiglioma effect of the well-known antidiabetic drug metformin. In low-density cultures of the C6 rat glioma cell line, metformin blocked the cell cycle progression in G(0)/G(1) phase without inducing significant cell death. In confluent C6 cultures, on the other hand, metformin caused massive induction of caspase-dependent apoptosis associated with c-Jun N-terminal kinase (JNK) activation, mitochondrial depolarization and oxidative stress. Metformin-triggered apoptosis was completely prevented by agents that block mitochondrial permeability transition (cyclosporin A) and oxygen radical production (N-acetylcisteine), while the inhibitors of JNK activation (SP600125) or glycolysis (sodium fluoride, iodoacetate) provided partial protection. The antiglioma effect of metformin was reduced by compound C, an inhibitor of AMP-activated protein kinase (AMPK), and was mimicked by the AMPK agonist AICAR. Similar effects were observed in the human glioma cell line U251, while rat primary astrocytes were completely resistant to the antiproliferative and proapoptotic action of metformin

    Antiglioma action of xanthones from Gentiana kochiana: Mechanistic and structure-activity requirements

    No full text
    The present study identifies xanthones gentiakochianin and gentiacaulein as the active principles responsible for the in vitro antiglioma action of ether and methanolic extracts of the plant Gentiana kochiana. Gentiakochianin and gentiacaulein induced cell cycle arrest in G(2)/M and G(0)/G(1) phases, respectively, in both C6 rat glioma and U251 human glioma cell lines. The more efficient antiproliferative action of gentiakochianin was associated with its ability to induce microtubule stabilization in a cell-free assay. Both the xanthones reduced mitochondrial membrane potential and increased the production of reactive oxygen species in glioma cells, but only the effects of gentiakochianin were pronounced enough to cause caspase activation and subsequent apoptotic cell death. The assessment of structure-activity relationship in a series of structurally related xanthones from G. kochiana and Gentianella austriaca revealed dihydroxylation at positions 7, 8 of the xanthonic nucleus as the key structural feature responsible for the ability of gentiakochianin to induce microtubule-associated G(2)/M cell block and apoptotic cell death in glioma cells. (C) 2008 Elsevier Ltd. All rights reserved.nul
    corecore