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Sample records for induced paclitaxel resistance

  1. Autophagy promotes paclitaxel resistance of cervical cancer cells: involvement of Warburg effect activated hypoxia-induced factor 1-?-mediated signaling

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    Peng, X; Gong, F; Chen, Y; Jiang, Y; Liu, J; Yu, M; Zhang, S; Wang, M; Xiao, G; Liao, H

    2014-01-01

    Paclitaxel is one of the most effective chemotherapy drugs for advanced cervical cancer. However, acquired resistance of paclitaxel represents a major barrier to successful anticancer treatment. In this study, paclitaxel-resistant HeLa sublines (HeLa-R cell lines) were established by continuous exposure and increased autophagy level was observed in HeLa-R cells. 3-Methyladenine or ATG7 siRNA, autophagy inhibitors, could restore sensitivity of HeLa-R cells to paclitaxel compared with parental ...

  2. Management of paclitaxel-induced neurotoxicity

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    Manisha Bhutani

    2011-12-01

    Full Text Available Paclitaxel exerts its antitumor activity by promoting microtubule assembly and stabilizing microtubules. Microtubules are important for the development and maintenance of neurons. As a consequence, neurotoxicity is one of the drug’s major side effects. The risk of neurotoxicity depends on dose, duration and schedule of paclitaxel. Risk increases for patients with pre-existing conditions that may cause neuropathy (such as alcohol consumption, diabetes, or renal disease or with simultaneous or prior exposure to other neurotoxic chemotherapy such as platinum-based drugs, vinca alkaloids, immunomodulators, proteasome inhibitors, and epothilones. Patients with paclitaxel-induced neurotoxicity (PINT experience a constellation of symptoms over the course of treatment and beyond, ranging from mild to severe. Typically, the clinical presentation reflects an axonal peripheral neuropathy with glove-and-stocking distribution sensory loss, combined with features suggestive of nerve hyperexcitability including paresthesia, dysesthesia, and pain. Proprioceptive and motor effects become apparent as neuropathy becomes more advanced. These symptoms may be prolonged, severe, disabling, relatively resistant to intervention and adversely affect activities of daily living and thereby quality of life. Management is mainly symptomatic and supportive. Despite attempts to minimize PINT with changes in dose, vehicle, delivery systems, infusion schedule and premedication or co-treatment with neuroprotective agents, PINT remains dose-limiting in many instances and is a barrier to achieving the desired clinical response.

  3. Paclitaxel-induced apoptosis is BAK-dependent, but BAX and BIM-independent in breast tumor.

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    Anna V Miller

    Full Text Available Paclitaxel (Taxol-induced cell death requires the intrinsic cell death pathway, but the specific participants and the precise mechanisms are poorly understood. Previous studies indicate that a BH3-only protein BIM (BCL-2 Interacting Mediator of cell death plays a role in paclitaxel-induced apoptosis. We show here that BIM is dispensable in apoptosis with paclitaxel treatment using bim(-/- MEFs (mouse embryonic fibroblasts, the bim(-/- mouse breast tumor model, and shRNA-mediated down-regulation of BIM in human breast cancer cells. In contrast, both bak (-/- MEFs and human breast cancer cells in which BAK was down-regulated by shRNA were more resistant to paclitaxel. However, paclitaxel sensitivity was not affected in bax(-/- MEFs or in human breast cancer cells in which BAX was down-regulated, suggesting that paclitaxel-induced apoptosis is BAK-dependent, but BAX-independent. In human breast cancer cells, paclitaxel treatment resulted in MCL-1 degradation which was prevented by a proteasome inhibitor, MG132. A Cdk inhibitor, roscovitine, blocked paclitaxel-induced MCL-1 degradation and apoptosis, suggesting that Cdk activation at mitotic arrest could induce subsequent MCL-1 degradation in a proteasome-dependent manner. BAK was associated with MCL-1 in untreated cells and became activated in concert with loss of MCL-1 expression and its release from the complex. Our data suggest that BAK is the mediator of paclitaxel-induced apoptosis and could be an alternative target for overcoming paclitaxel resistance.

  4. Paclitaxel Induces Apoptosis in Breast Cancer Cells through Different Calcium—Regulating Mechanisms Depending on External Calcium Conditions

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    Pan, Zhi; Avila, Andrew; Gollahon, Lauren

    2014-01-01

    Previously, we reported that endoplasmic reticulum calcium stores were a direct target for paclitaxel initiation of apoptosis. Furthermore, the actions of paclitaxel attenuated Bcl-2 resistance to apoptosis through endoplasmic reticulum-mediated calcium release. To better understand the calcium-regulated mechanisms of paclitaxel-induced apoptosis in breast cancer cells, we investigated the role of extracellular calcium, specifically; whether influx of extracellular calcium contributed to and/or was necessary for paclitaxel-induced apoptosis. Our results demonstrated that paclitaxel induced extracellular calcium influx. This mobilization of extracellular calcium contributed to subsequent cytosolic calcium elevation differently, depending on dosage. Under normal extracellular calcium conditions, high dose paclitaxel induced apoptosis-promoting calcium influx, which did not occur in calcium-free conditions. In the absence of extracellular calcium an “Enhanced Calcium Efflux” mechanism in which high dose paclitaxel stimulated calcium efflux immediately, leading to dramatic cytosolic calcium decrease, was observed. In the absence of extracellular calcium, high dose paclitaxel’s stimulatory effects on capacitative calcium entry and apoptosis could not be completely restored. Thus, normal extracellular calcium concentrations are critical for high dose paclitaxel-induced apoptosis. In contrast, low dose paclitaxel mirrored controls, indicating that it occurs independent of extracellular calcium. Thus, extracellular calcium conditions only affect efficacy of high dose paclitaxel-induced apoptosis. PMID:24549172

  5. Herbal Medicine Goshajinkigan Prevents Paclitaxel-Induced Mechanical Allodynia without Impairing Antitumor Activity of Paclitaxel

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    Muh. Akbar Bahar

    2013-01-01

    Full Text Available Chemotherapy-induced peripheral neuropathy is a major dose-limiting side effect of commonly used chemotherapeutic agents. However, there are no effective strategies to treat the neuropathy. We examined whether Goshajinkigan, a herbal medicine, would prevent paclitaxel-induced allodynia without affecting the anticancer action in mice. Murine breast cancer 4T1 cells were inoculated into the mammary fat pad. Paclitaxel (10 and 20 mg/kg, intraperitoneal, alternate day from day 7 postinoculation inhibited the tumor growth, and Goshajinkigan (1 g/kg, oral, daily from day 2 postinoculation did not affect the antitumor action of paclitaxel. Mechanical allodynia developed in the inoculated region due to tumor growth and in the hind paw due to paclitaxel-induced neuropathy. Paclitaxel-induced allodynia was markedly prevented by Goshajinkigan, although tumor-associated allodynia was not inhibited by Goshajinkigan. These results suggest that Goshajinkigan prevents paclitaxel-induced peripheral neuropathy without interfering with the anti-cancer action of paclitaxel.

  6. Paclitaxel-induced epithelial damage and ectopic MMP-13 expression promotes neurotoxicity in zebrafish.

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    Lisse, Thomas S; Middleton, Leah J; Pellegrini, Adriana D; Martin, Paige B; Spaulding, Emily L; Lopes, Olivia; Brochu, Elizabeth A; Carter, Erin V; Waldron, Ashley; Rieger, Sandra

    2016-04-12

    Paclitaxel is a microtubule-stabilizing chemotherapeutic agent that is widely used in cancer treatment and in a number of curative and palliative regimens. Despite its beneficial effects on cancer, paclitaxel also damages healthy tissues, most prominently the peripheral sensory nervous system. The mechanisms leading to paclitaxel-induced peripheral neuropathy remain elusive, and therapies that prevent or alleviate this condition are not available. We established a zebrafish in vivo model to study the underlying mechanisms and to identify pharmacological agents that may be developed into therapeutics. Both adult and larval zebrafish displayed signs of paclitaxel neurotoxicity, including sensory axon degeneration and the loss of touch response in the distal caudal fin. Intriguingly, studies in zebrafish larvae showed that paclitaxel rapidly promotes epithelial damage and decreased mechanical stress resistance of the skin before induction of axon degeneration. Moreover, injured paclitaxel-treated zebrafish skin and scratch-wounded human keratinocytes (HEK001) display reduced healing capacity. Epithelial damage correlated with rapid accumulation of fluorescein-conjugated paclitaxel in epidermal basal keratinocytes, but not axons, and up-regulation of matrix-metalloproteinase 13 (MMP-13, collagenase 3) in the skin. Pharmacological inhibition of MMP-13, in contrast, largely rescued paclitaxel-induced epithelial damage and neurotoxicity, whereas MMP-13 overexpression in zebrafish embryos rendered the skin vulnerable to injury under mechanical stress conditions. Thus, our studies provide evidence that the epidermis plays a critical role in this condition, and we provide a previously unidentified candidate for therapeutic interventions.

  7. Herbal Medicine Goshajinkigan Prevents Paclitaxel-Induced Mechanical Allodynia without Impairing Antitumor Activity of Paclitaxel

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    Bahar, Muh. Akbar; Andoh, Tsugunobu; Ogura, Keisuke; Hayakawa, Yoshihiro; Saiki, Ikuo; Kuraishi, Yasushi

    2013-01-01

    Chemotherapy-induced peripheral neuropathy is a major dose-limiting side effect of commonly used chemotherapeutic agents. However, there are no effective strategies to treat the neuropathy. We examined whether Goshajinkigan, a herbal medicine, would prevent paclitaxel-induced allodynia without affecting the anticancer action in mice. Murine breast cancer 4T1 cells were inoculated into the mammary fat pad. Paclitaxel (10 and 20 mg/kg, intraperitoneal, alternate day from day 7 postinoculation) ...

  8. Loss of FBXW7 and accumulation of MCL1 and PLK1 promote paclitaxel resistance in breast cancer.

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    Gasca, Jessica; Flores, Maria Luz; Giráldez, Servando; Ruiz-Borrego, Manuel; Tortolero, María; Romero, Francisco; Japón, Miguel A; Sáez, Carmen

    2016-08-16

    FBXW7 is a component of SCF (complex of SKP1, CUL1 and F-box-protein)-type ubiquitin ligases that targets several oncoproteins for ubiquitination and degradation by the proteasome. FBXW7 regulates cellular apoptosis by targeting MCL1 for ubiquitination. Recently, we identified PLK1 as a new substrate of FBXW7 modulating the intra-S-phase DNA-damage checkpoint. Taxanes are frequently used in breast cancer treatments, but the acquisition of resistance makes these treatments ineffective. We investigated the role of FBXW7 and their substrates MCL1 and PLK1 in regulating the apoptotic response to paclitaxel treatment in breast cancer cells and their expression in breast cancer tissues. Paclitaxel-sensitive MDA-MB-468 and a paclitaxel-resistant MDA-MB-468R subclone were used to study the role of FBXW7 and substrates in paclitaxel-induced apoptosis. Forced expression of FBXW7 or downregulation of MCL1 or PLK1 restored sensitivity to paclitaxel in MDA-MB-468R cells. By contrary, FBXW7-silenced MDA-MB-468 cells became resistant to paclitaxel. The expression of FBXW7 and substrates were studied in 296 invasive carcinomas by immunohistochemistry and disease-free survival was analyzed in a subset of patients treated with paclitaxel. In breast cancer tissues, loss of FBXW7 correlated with adverse prognosis markers and loss of FBXW7 and MCL1 or PLK1 accumulation were associated with diminished disease-free survival in paclitaxel-treated patients. We conclude that FBXW7 regulates the response to paclitaxel by targeting MCL1 and PLK1 in breast cancer cells and thus targeting these substrates may be a valuable adjunct for paclitaxel treatment. Also, FBXW7, MCL1 and PLK1 may be relevant predictive markers of tumor progression and response to paclitaxel treatment.

  9. Curcumin increases the sensitivity of Paclitaxel-resistant NSCLC cells to Paclitaxel through microRNA-30c-mediated MTA1 reduction.

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    Lu, Yimin; Wang, Jun; Liu, Lei; Yu, Lequn; Zhao, Nian; Zhou, Xingju; Lu, Xudong

    2017-04-01

    Non-small-cell lung cancer is one of the most lethal cancers in the worldwide. Although Paclitaxel-based combinational therapies have long been used as a standard treatment in aggressive non-small-cell lung cancers, Paclitaxel resistance emerges as a major clinical problem. It has been demonstrated that Curcumin from Curcuma longa as a traditional Chinese medicine can inhibit cancer cell proliferation. However, the role of Curcumin in Paclitaxel-resistant non-small-cell lung cancer cells is not clear. In this study, we investigated the effect of Curcumin on the Paclitaxel-resistant non-small-cell lung cancer cells and found that Curcumin treatment markedly increased the sensitivity of Paclitaxel-resistant non-small-cell lung cancer cells to Paclitaxel. Mechanically, the study revealed that Curcumin could reduce the expression of metastasis-associated gene 1 (MTA1) gene through upregulation of microRNA-30c in Paclitaxel-resistant non-small-cell lung cancer cells. During the course, MTA1 reduction sensitized Paclitaxel-resistant non-small-cell lung cancer cells and enhanced the effect of Paclitaxel. Taken together, our studies indicate that Curcumin increases the sensitivity of Paclitaxel-resistant non-small-cell lung cancer cells to Paclitaxel through microRNA-30c-mediated MTA1 reduction. Curcumin might be a potential adjuvant for non-small-cell lung cancer patients during Paclitaxel treatment.

  10. Studies of peripheral sensory nerves in paclitaxel-induced painful peripheral neuropathy: Evidence for mitochondrial dysfunction

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    Flatters, Sarah J.L.; Bennett, Gary J.

    2006-01-01

    Paclitaxel chemotherapy frequently induces neuropathic pain during and often persisting after therapy. The mechanisms responsible for this pain are unknown. Using a rat model of paclitaxel-induced painful peripheral neuropathy, we have performed studies to search for peripheral nerve pathology. Paclitaxel-induced mechano-allodynia and mechano-hyperalgesia were evident after a short delay, peaked at day 27 and finally resolved on day 155. Paclitaxel- and vehicle-treated rats were perfused on d...

  11. Neurotoxic 1-deoxysphingolipids and paclitaxel-induced peripheral neuropathy

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    Kramer, Rita; Bielawski, Jacek; Kistner-Griffin, Emily; Othman, Alaa; Alecu, Irina; Ernst, Daniela; Kornhauser, Drew; Hornemann, Thorsten; Spassieva, Stefka

    2015-01-01

    Peripheral neuropathy is a major dose-limiting side effect of paclitaxel and cisplatin chemotherapy. In the current study, we tested the involvement of a novel class of neurotoxic sphingolipids, the 1-deoxysphingolipids. 1-Deoxysphingolipids are produced when the enzyme serine palmitoyltransferase uses l-alanine instead of l-serine as its amino acid substrate. We tested whether treatment of cells with paclitaxel (250 nM, 1 µM) and cisplatin (250 nM, 1 µM) would result in elevated cellular levels of 1-deoxysphingolipids. Our results revealed that paclitaxel, but not cisplatin treatment, caused a dose-dependent elevation of 1-deoxysphingolipids levels and an increase in the message and activity of serine palmitoyltransferase (P peripheral neuropathy symptoms [evaluated by the European Organization for Research and Treatment of Cancer (EORTC) QLQ-chemotherapy-induced peripheral neuropathy-20 (CIPN20) instrument] and the 1-deoxysphingolipid plasma levels (measured by mass spectrometry) in 27 patients with breast cancer who were treated with paclitaxel chemotherapy. Our results showed that there was an association between the incidence and severity of neuropathy and the levels of very-long-chain 1-deoxyceramides such as C24 (P neuropathy (P peripheral neuropathy.—Kramer, R., Bielawski, J., Kistner-Griffin, E., Othman, A., Alecu, I., Ernst, D., Kornhauser, D., Hornemann, T., Spassieva, S. Neurotoxic 1-deoxysphingolipids and paclitaxel-induced peripheral neuropathy. PMID:26198449

  12. Characterization of acquired paclitaxel resistance of breast cancer cells and involvement of ABC transporters

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    Němcová-Fürstová, Vlasta; Kopperová, Dana; Balušíková, Kamila; Ehrlichová, Marie; Brynychová, Veronika; Václavíková, Radka; Daniel, Petr; Souček, Pavel; Kovář, Jan

    2016-01-01

    Development of taxane resistance has become clinically very important issue. The molecular mechanisms underlying the resistance are still unclear. To address this issue, we established paclitaxel-resistant sublines of the SK-BR-3 and MCF-7 breast cancer cell lines that are capable of long-term proliferation in 100 nM and 300 nM paclitaxel, respectively. Application of these concentrations leads to cell death in the original counterpart cells. Both sublines are cross-resistant to doxorubicin, indicating the presence of the MDR phenotype. Interestingly, resistance in both paclitaxel-resistant sublines is circumvented by the second-generation taxane SB-T-1216. Moreover, we demonstrated that it was not possible to establish sublines of SK-BR-3 and MCF-7 cells resistant to this taxane. It means that at least the tested breast cancer cells are unable to develop resistance to some taxanes. Employing mRNA expression profiling of all known human ABC transporters and subsequent Western blot analysis of the expression of selected transporters, we demonstrated that only the ABCB1/PgP and ABCC3/MRP3 proteins were up-regulated in both paclitaxel-resistant sublines. We found up-regulation of ABCG2/BCRP and ABCC4 proteins only in paclitaxel-resistant SK-BR-3 cells. In paclitaxel-resistant MCF-7 cells, ABCB4/MDR3 and ABCC2/MRP2 proteins were up-regulated. Silencing of ABCB1 expression using specific siRNA increased significantly, but did not completely restore full sensitivity to both paclitaxel and doxorubicin. Thus we showed a key, but not exclusive, role for ABCB1 in mechanisms of paclitaxel resistance. It suggests the involvement of multiple mechanisms in paclitaxel resistance in tested breast cancer cells. - Highlights: • Expression of all ABC transporters in paclitaxel-resistant sublines of SK-BR-3 and MCF-7 cells was analyzed. • SK-BR-3 and MCF-7 cells are unable to develop resistance to some taxanes. • Some taxanes are able to overcome developed resistance to

  13. Characterization of acquired paclitaxel resistance of breast cancer cells and involvement of ABC transporters

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    Němcová-Fürstová, Vlasta, E-mail: vlasta.furstova@lf3.cuni.cz [Division of Cell and Molecular Biology, Third Faculty of Medicine, Charles University, Prague (Czech Republic); Kopperová, Dana; Balušíková, Kamila [Division of Cell and Molecular Biology, Third Faculty of Medicine, Charles University, Prague (Czech Republic); Ehrlichová, Marie; Brynychová, Veronika; Václavíková, Radka [Toxicogenomics Unit, National Institute of Public Health, Prague (Czech Republic); Daniel, Petr [Division of Cell and Molecular Biology, Third Faculty of Medicine, Charles University, Prague (Czech Republic); Souček, Pavel [Toxicogenomics Unit, National Institute of Public Health, Prague (Czech Republic); Kovář, Jan [Division of Cell and Molecular Biology, Third Faculty of Medicine, Charles University, Prague (Czech Republic)

    2016-11-01

    Development of taxane resistance has become clinically very important issue. The molecular mechanisms underlying the resistance are still unclear. To address this issue, we established paclitaxel-resistant sublines of the SK-BR-3 and MCF-7 breast cancer cell lines that are capable of long-term proliferation in 100 nM and 300 nM paclitaxel, respectively. Application of these concentrations leads to cell death in the original counterpart cells. Both sublines are cross-resistant to doxorubicin, indicating the presence of the MDR phenotype. Interestingly, resistance in both paclitaxel-resistant sublines is circumvented by the second-generation taxane SB-T-1216. Moreover, we demonstrated that it was not possible to establish sublines of SK-BR-3 and MCF-7 cells resistant to this taxane. It means that at least the tested breast cancer cells are unable to develop resistance to some taxanes. Employing mRNA expression profiling of all known human ABC transporters and subsequent Western blot analysis of the expression of selected transporters, we demonstrated that only the ABCB1/PgP and ABCC3/MRP3 proteins were up-regulated in both paclitaxel-resistant sublines. We found up-regulation of ABCG2/BCRP and ABCC4 proteins only in paclitaxel-resistant SK-BR-3 cells. In paclitaxel-resistant MCF-7 cells, ABCB4/MDR3 and ABCC2/MRP2 proteins were up-regulated. Silencing of ABCB1 expression using specific siRNA increased significantly, but did not completely restore full sensitivity to both paclitaxel and doxorubicin. Thus we showed a key, but not exclusive, role for ABCB1 in mechanisms of paclitaxel resistance. It suggests the involvement of multiple mechanisms in paclitaxel resistance in tested breast cancer cells. - Highlights: • Expression of all ABC transporters in paclitaxel-resistant sublines of SK-BR-3 and MCF-7 cells was analyzed. • SK-BR-3 and MCF-7 cells are unable to develop resistance to some taxanes. • Some taxanes are able to overcome developed resistance to

  14. Vasodilatation in the rat dorsal hindpaw induced by activation of sensory neurons is reduced by Paclitaxel

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    Gracias, N.G.; Cummins, T.R.; Kelley, M.R.; Basile, D.P.; Iqbal, T.; Vasko, M.R.

    2010-01-01

    Peripheral neuropathy is a major side effect following treatment with the cancer chemotherapeutic drug paclitaxel. Whether paclitaxel-induced peripheral neuropathy is secondary to altered function of small diameter sensory neurons remains controversial. To ascertain whether the function of the small diameter sensory neurons was altered following systemic administration of paclitaxel, we injected male Sprague Dawley rats with 1 mg/kg paclitaxel every other day for a total of four doses and exa...

  15. Cold therapy to prevent paclitaxel-induced peripheral neuropathy.

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    Griffiths, Claire; Kwon, Nancy; Beaumont, Jennifer L; Paice, Judith A

    2018-04-21

    This case-control study was designed to assess the efficacy of cryotherapy to prevent paclitaxel-induced painful peripheral neuropathy in women with breast cancer. Participants served as their own paired control, with randomization of the cooled glove/sock to either the dominant or the non-dominant hand/foot, worn for 15 min prior to, during, and 15 min after completion of the paclitaxel infusion. Outcome measures included the Neuropathic Pain Symptom Inventory, the Brief Pain Inventory, and quantitative sensory testing. Data were measured at each of six time points-baseline, post-treatment (approximately 2 weeks after the last paclitaxel infusion), and at the first, fifth, ninth, and final weekly paclitaxel treatments. Of 29 randomized participants, 20 (69%) received at least one cryotherapy treatment, and 11 (38%) received all four cryotherapy treatments. Ten (34%) participants could not tolerate the cryotherapy, and six (21%) declined further participation at some point during the trial. Only seven participants (24%) were available for the final post-chemotherapy QST and questionnaires. There were no significant differences in measures of neuropathy or pain between treated and untreated hands or feet. Strategies to prevent painful peripheral neuropathy are urgently needed. In this current trial, dropout due to discomfort precluded adequate power to fully understand the potential benefits of cryotherapy. Much more research is needed to discover safe and effective preventive strategies that can be easily implemented within busy infusion centers.

  16. Proinflammatory Factors Mediate Paclitaxel-Induced Impairment of Learning and Memory

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    Zhao Li

    2018-01-01

    Full Text Available The chemotherapeutic agent paclitaxel is widely used for cancer treatment. Paclitaxel treatment impairs learning and memory function, a side effect that reduces the quality of life of cancer survivors. However, the neural mechanisms underlying paclitaxel-induced impairment of learning and memory remain unclear. Paclitaxel treatment leads to proinflammatory factor release and neuronal apoptosis. Thus, we hypothesized that paclitaxel impairs learning and memory function through proinflammatory factor-induced neuronal apoptosis. Neuronal apoptosis was assessed by TUNEL assay in the hippocampus. Protein expression levels of tumor necrosis factor-α (TNF-α and interleukin-1β (IL-1β in the hippocampus tissue were analyzed by Western blot assay. Spatial learning and memory function were determined by using the Morris water maze (MWM test. Paclitaxel treatment significantly increased the escape latencies and decreased the number of crossing in the MWM test. Furthermore, paclitaxel significantly increased the number of TUNEL-positive neurons in the hippocampus. Also, paclitaxel treatment increased the expression levels of TNF-α and IL-1β in the hippocampus tissue. In addition, the TNF-α synthesis inhibitor thalidomide significantly attenuated the number of paclitaxel-induced TUNEL-positive neurons in the hippocampus and restored the impaired spatial learning and memory function in paclitaxel-treated rats. These data suggest that TNF-α is critically involved in the paclitaxel-induced impairment of learning and memory function.

  17. Prevention of paclitaxel-induced peripheral neuropathy by lithium pretreatment

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    Mo, Michelle; Erdelyi, Ildiko; Szigeti-Buck, Klara; Benbow, Jennifer H.; Ehrlich, Barbara E.

    2012-01-01

    Chemotherapy-induced peripheral neuropathy (CIPN) is a debilitating side effect that occurs in many patients undergoing chemotherapy. It is often irreversible and frequently leads to early termination of treatment. In this study, we have identified two compounds, lithium and ibudilast, that when administered as a single prophylactic injection prior to paclitaxel treatment, prevent the development of CIPN in mice at the sensory-motor and cellular level. The prevention of neuropathy was not obs...

  18. Polaprezinc reduces paclitaxel-induced peripheral neuropathy in rats without affecting anti-tumor activity

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    Kuniaki Tsutsumi

    2016-06-01

    Full Text Available Paclitaxel, an anticancer drug, frequently causes painful peripheral neuropathy. In this study, we investigated the preventive effect of polaprezinc on paclitaxel-induced peripheral neuropathy in rats. Polaprezinc (3 mg/kg, p.o., once daily inhibited the development of mechanical allodynia induced by paclitaxel (4 mg/kg, i.p., on days 1, 3, 5 and 7 and suppressed the paclitaxel-induced increase in macrophage migration in dorsal root ganglion cells. In addition, polaprezinc did not affect the anti-tumor activity of paclitaxel in cultured cell lines or tumor-bearing mice. These results suggest a clinical indication for polaprezinc in the prevention of paclitaxel-induced neuropathy.

  19. Polaprezinc reduces paclitaxel-induced peripheral neuropathy in rats without affecting anti-tumor activity

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    Kuniaki Tsutsumi; Takanori Kaname; Haruka Shiraishi; Takehiro Kawashiri; Nobuaki Egashira

    2016-01-01

    Paclitaxel, an anticancer drug, frequently causes painful peripheral neuropathy. In this study, we investigated the preventive effect of polaprezinc on paclitaxel-induced peripheral neuropathy in rats. Polaprezinc (3 mg/kg, p.o., once daily) inhibited the development of mechanical allodynia induced by paclitaxel (4 mg/kg, i.p., on days 1, 3, 5 and 7) and suppressed the paclitaxel-induced increase in macrophage migration in dorsal root ganglion cells. In addition, polaprezinc did not affect th...

  20. Role of satellite cell-derived l-serine in the dorsal root ganglion in paclitaxel-induced painful peripheral neuropathy

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    Kiya, T; Kawamata, T; Namiki, A; Yamakage, M

    2011-01-01

    Paclitaxel is one of the most commonly used antineoplastic drugs for the treatment of solid tumors. Unfortunately, its use is often associated with dose-limiting painful peripheral neuropathy and subsequent neuropathic pain that is resistant to standard analgesics. However, there are few clinically available drugs or drug classes for the treatment of paclitaxel-induced neuropathy due to a lack of information regarding the mechanisms responsible for it. In this study, we examined the involveme...

  1. Development of a hybrid paclitaxel-loaded arsenite nanoparticle (HPAN) delivery system for synergistic combined therapy of paclitaxel-resistant cancer

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    Chen, Fei-yan; Zhang, Yu [Nanchang University, College of Chemistry (China); Chen, Xiang-yu [Xiangya No.2 Hospital of Central South University, Department of Radiology (China); Li, Jia-qian; Xiao, Xiao-ping; Yu, Lu-lu; Tang, Qun, E-mail: tangqun@ncu.edu.cn [Nanchang University, Institute for Advanced Study (China)

    2017-04-15

    Multidrug resistance (MDR) is a major reason for failure of chemotherapy in a variety of human tumors. For instance, paclitaxel (PTX) has been widely used as a first-line anticancer drug, but resistance to PTX is becoming increasingly serious. Herein, we propose a strategy of combined therapy to overcome MDR of PTX by introducing a hybrid paclitaxel-loaded gadolinium arsenite nanoparticle (HPAN), where PTX was conjugated with rod-shaped gadolinium arsenite (GdAsO{sub x}) nanoparticle (NP). Triggered by endogenous inorganic phosphate (Pi), the hybrid nanoparticles readily collapse, thereby releasing PTX and arsenic trioxide (ATO). An MTT assay indicated IC50 values for HPAN one order of magnitude lower than for a simple equivalent mixture of PTX and ATO against PTX-resistant human colon cancer cells (HCT 166), indicating remarkable synergistic effect. Species type-dependent cellular uptake, induced apoptosis, and cell cycle modulation were also evaluated. Cellular uptake tests indicate that the HPAN presents higher PTX intracellular loading for the PTX-resistant cells and longer intracellular retention time, displaying resistance to drug efflux from the cancer cell than pristine PTX or the equivalent mixture of PTX and ATO. Cell cycle and apoptosis tests consistently proved that addition of HPAN resulted in higher G2/M and apoptosis in PTX-resistant cells. In vivo anticancer experiments evidenced that HPAN had better therapeutic effect on the resistant tumor in the murine xenograft model than pristine PTX or a mixture of PTX and ATO. Our results suggest that HPAN might enhance the therapeutic index and overcome PTX resistance and also demonstrate that the combined therapy is not only related to the species of combined agents but also their physiochemical states.

  2. Global inhibition of reactive oxygen species (ROS inhibits paclitaxel-induced painful peripheral neuropathy.

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    Mehmet Fidanboylu

    Full Text Available Paclitaxel (Taxol® is a widely used chemotherapeutic agent that has a major dose limiting side-effect of painful peripheral neuropathy. Currently there is no effective therapy for the prevention or treatment of chemotherapy-induced painful peripheral neuropathies. Evidence for mitochondrial dysfunction during paclitaxel-induced pain was previously indicated with the presence of swollen and vacuolated neuronal mitochondria. As mitochondria are a major source of reactive oxygen species (ROS, the aim of this study was to examine whether pharmacological inhibition of ROS could reverse established paclitaxel-induced pain or prevent the development of paclitaxel-induced pain. Using a rat model of paclitaxel-induced pain (intraperitoneal 2 mg/kg paclitaxel on days 0, 2, 4 & 6, the effects of a non-specific ROS scavenger, N-tert-Butyl-α-phenylnitrone (PBN and a superoxide selective scavenger, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL were compared. Systemic 100 mg/kg PBN administration markedly inhibited established paclitaxel-induced mechanical hypersensitivity to von Frey 8 g and 15 g stimulation and cold hypersensitivity to plantar acetone application. Daily systemic administration of 50 mg/kg PBN (days -1 to 13 completely prevented mechanical hypersensitivity to von Frey 4 g and 8 g stimulation and significantly attenuated mechanical hypersensitivity to von Frey 15 g. Systemic 100 mg/kg TEMPOL had no effect on established paclitaxel-induced mechanical or cold hypersensitivity. High dose (250 mg/kg systemic TEMPOL significantly inhibited mechanical hypersensitivity to von Frey 8 g & 15 g, but to a lesser extent than PBN. Daily systemic administration of 100 mg/kg TEMPOL (day -1 to 12 did not affect the development of paclitaxel-induced mechanical hypersensitivity. These data suggest that ROS play a causal role in the development and maintenance of paclitaxel-induced pain, but such effects cannot be attributed to superoxide radicals

  3. MENA Confers Resistance to Paclitaxel in Triple-Negative Breast Cancer.

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    Oudin, Madeleine J; Barbier, Lucie; Schäfer, Claudia; Kosciuk, Tatsiana; Miller, Miles A; Han, Sangyoon; Jonas, Oliver; Lauffenburger, Douglas A; Gertler, Frank B

    2017-01-01

    Taxane therapy remains the standard of care for triple-negative breast cancer. However, high frequencies of recurrence and progression in treated patients indicate that metastatic breast cancer cells can acquire resistance to this drug. The actin regulatory protein MENA and particularly its invasive isoform, MENA INV , are established drivers of metastasis. MENA INV expression is significantly correlated with metastasis and poor outcome in human patients with breast cancer. We investigated whether MENA isoforms might play a role in driving resistance to chemotherapeutics. We find that both MENA and MENA INV confer resistance to the taxane paclitaxel, but not to the widely used DNA-damaging agents doxorubicin or cisplatin. Furthermore, paclitaxel treatment does not attenuate growth of MENA INV -driven metastatic lesions. Mechanistically, MENA isoform expression alters the ratio of dynamic and stable microtubule populations in paclitaxel-treated cells. MENA expression also increases MAPK signaling in response to paclitaxel treatment. Decreasing ERK phosphorylation by co-treatment with MEK inhibitor restored paclitaxel sensitivity by driving microtubule stabilization in MENA isoform-expressing cells. Our results reveal a novel mechanism of taxane resistance in highly metastatic breast cancer cells and identify a combination therapy to overcome such resistance. Mol Cancer Ther; 16(1); 143-55. ©2016 AACR. ©2016 American Association for Cancer Research.

  4. Novel oral administrated paclitaxel micelles with enhanced bioavailability and antitumor efficacy for resistant breast cancer.

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    Zhang, Ting; Luo, Jingwen; Fu, Yao; Li, Hanmei; Ding, Rui; Gong, Tao; Zhang, Zhirong

    2017-02-01

    Paclitaxel (PTX) is a widely used antineoplastic drug in clinic. Due to poor aqueous solubility, it is administrated by intravenous infusion of cremophor EL containing formulation with serious adverse effects. The low oral bioavailability is a great challenge for oral formulation development. In addition, P-gp mediated multidrug resistance limit its clinical use in various resistant cancers. In this study, a novel super-antiresistant PTX micelle formulation for oral administration was developed. A P-gp inhibitor, bromotetrandrine (W198) was co-encapsulated in the micelle. The micelles were composed of Solutol HS 15 and d-a-tocopheryl polyethylene glycol succinate to avoid Cremophor EL induced toxicity. The micelles were round with a mean particle size of ∼13nm and an encapsulation efficiency of ∼90%. A series of in vitro evaluations were performed in non-resistant MCF-7 cells and resistant MCF-7/Adr cells. The super-antiresistant PTX micelles showed higher cell uptake efficiency, significantly increased cytotoxicity and antimitotic effect in drug resistant MCF-7/Adr cells when compared with Taxol and other PTX micelle formulations. Compared with Taxol, the super-antiresistant PTX micelles significantly improved bioavailability after oral administration in rats, and inhibited tumor growth in multidrug resistance xenografted MCF-7/Adr nude mice. In summary, the noval super-antiresistant PTX micelles showed a great potential for oral delivery of PTX against resistant breast cancer. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Pharmacological Modulation of the Mitochondrial Electron Transport Chain in Paclitaxel-Induced Painful Peripheral Neuropathy.

    Science.gov (United States)

    Griffiths, Lisa A; Flatters, Sarah J L

    2015-10-01

    Paclitaxel is an effective first-line chemotherapeutic with the major dose-limiting side effect of painful neuropathy. Mitochondrial dysfunction and oxidative stress have been implicated in paclitaxel-induced painful neuropathy. Here we show the effects of pharmacological modulation of mitochondrial sites that produce reactive oxygen species using systemic rotenone (complex I inhibitor) or antimycin A (complex III inhibitor) on the maintenance and development of paclitaxel-induced mechanical hypersensitivity in adult male Sprague Dawley rats. The maximally tolerated dose (5 mg/kg) of rotenone inhibited established paclitaxel-induced mechanical hypersensitivity. However, some of these inhibitory effects coincided with decreased motor coordination; 3 mg/kg rotenone also significantly attenuated established paclitaxel-induced mechanical hypersensitivity without any motor impairment. The maximally tolerated dose (.6 mg/kg) of antimycin A reversed established paclitaxel-induced mechanical hypersensitivity without any motor impairment. Seven daily doses of systemic rotenone or antimycin A were given either after paclitaxel administration or before and during paclitaxel administration. Rotenone had no significant effect on the development of paclitaxel-induced mechanical hypersensitivity. However, antimycin A significantly inhibited the development of paclitaxel-induced mechanical hypersensitivity when given before and during paclitaxel administration but had no effect when given after paclitaxel administration. These studies provide further evidence of paclitaxel-evoked mitochondrial dysfunction in vivo, suggesting that complex III activity is instrumental in paclitaxel-induced pain. This study provides further in vivo evidence that mitochondrial dysfunction is a key contributor to the development and maintenance of chemotherapy-induced painful neuropathy. This work also indicates that selective modulation of the electron transport chain can induce antinociceptive

  6. Role of cytochrome P450 2C8*3 (CYP2C8*3) in paclitaxel metabolism and paclitaxel-induced neurotoxicity

    DEFF Research Database (Denmark)

    Lee, Mi-Young; Apellániz-Ruiz, María; Johansson, Inger

    2015-01-01

    AIM: The CYP2C8*3 allele has been suggested as a risk factor for paclitaxel-induced neuropathy but the data hitherto published are conflicting. MATERIALS & METHODS: In total 435 patients were investigated with respect to maximum neuropathy grade and accumulated paclitaxel dose. The enzymatic prop...

  7. CX3CL1-mediated macrophage activation contributed to paclitaxel-induced DRG neuronal apoptosis and painful peripheral neuropathy.

    Science.gov (United States)

    Huang, Zhen-Zhen; Li, Dai; Liu, Cui-Cui; Cui, Yu; Zhu, He-Quan; Zhang, Wen-Wen; Li, Yong-Yong; Xin, Wen-Jun

    2014-08-01

    Painful peripheral neuropathy is a dose-limiting side effect of paclitaxel therapy, which hampers the optimal clinical management of chemotherapy in cancer patients. Currently the underlying mechanisms remain largely unknown. Here we showed that the clinically relevant dose of paclitaxel (3×8mg/kg, cumulative dose 24mg/kg) induced significant upregulation of the chemokine CX3CL1 in the A-fiber primary sensory neurons in vivo and in vitro and infiltration of macrophages into the dorsal root ganglion (DRG) in rats. Paclitaxel treatment also increased cleaved caspase-3 expression, induced the loss of primary afferent terminal fibers and decreased sciatic-evoked A-fiber responses in the spinal dorsal horn, indicating DRG neuronal apoptosis induced by paclitaxel. In addition, the paclitaxel-induced DRG neuronal apoptosis occurred exclusively in the presence of macrophage in vitro study. Intrathecal or systemic injection of CX3CL1 neutralizing antibody blocked paclitaxel-induced macrophage recruitment and neuronal apoptosis in the DRG, and also attenuated paclitaxel-induced allodynia. Furthermore, depletion of macrophage by systemic administration of clodronate inhibited paclitaxel-induced allodynia. Blocking CX3CL1 decreased activation of p38 MAPK in the macrophage, and inhibition of p38 MAPK activity blocked the neuronal apoptosis and development of mechanical allodynia induced by paclitaxel. These findings provide novel evidence that CX3CL1-recruited macrophage contributed to paclitaxel-induced DRG neuronal apoptosis and painful peripheral neuropathy. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Global Inhibition of Reactive Oxygen Species (ROS) Inhibits Paclitaxel-Induced Painful Peripheral Neuropathy

    OpenAIRE

    Fidanboylu, Mehmet; Griffiths, Lisa A.; Flatters, Sarah J. L.

    2011-01-01

    Paclitaxel (Taxol (R)) is a widely used chemotherapeutic agent that has a major dose limiting side-effect of painful peripheral neuropathy. Currently there is no effective therapy for the prevention or treatment of chemotherapy-induced painful peripheral neuropathies. Evidence for mitochondrial dysfunction during paclitaxel-induced pain was previously indicated with the presence of swollen and vacuolated neuronal mitochondria. As mitochondria are a major source of reactive oxygen species (ROS...

  9. Nanohybrid systems of non-ionic surfactant inserting liposomes loading paclitaxel for reversal of multidrug resistance.

    Science.gov (United States)

    Ji, Xiufeng; Gao, Yu; Chen, Lingli; Zhang, Zhiwen; Deng, Yihui; Li, Yaping

    2012-01-17

    Three new nanohybrid systems of non-ionic surfactant inserting liposomes loading paclitaxel (PTX) (NLPs) were prepared to overcome multidrug resistance (MDR) in PTX-resistance human lung cancer cell line. Three non-ionic surfactants, Solutol HS 15 (HS-15), pluronic F68 (PF-68) and cremophor EL (CrEL) were inserted into liposomes by film hydration method to form NLPs with an average size of around 110, 180 and 110 nm, respectively. There was an obvious increase of rhodamin 123 (Rh123) accumulation in A549/T cells after treated with nanohybrid systems loading Rh123 (NLRs) when compared with free Rh123 or liposomes loading Rh123 without surfactants (LRs), which indicated the significant inhibition effects of NLRs on drug efflux. The P-gp detection and ATP determination demonstrated that BNLs could not only interfere P-gp expression on the membrane of drug resistant cells, but also decrease ATP level in the cells. The cytotoxicity of NLPs against A549/T cells was higher than PTX loaded liposomes without surfactants (LPs), and the best result was achieved after treated with NLPs2. The apoptotic assay and the cell cycle analysis showed that NLPs could induce more apoptotic cells in drug resistant cells when compared with LPs. These results suggested that NLPs could overcome MDR by combination of drug delivery, P-gp inhibition and ATP depletion, and showed potential for treatment of MDR. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Nicotine Prevents and Reverses Paclitaxel-Induced Mechanical Allodynia in a Mouse Model of CIPN.

    Science.gov (United States)

    Kyte, S Lauren; Toma, Wisam; Bagdas, Deniz; Meade, Julie A; Schurman, Lesley D; Lichtman, Aron H; Chen, Zhi-Jian; Del Fabbro, Egidio; Fang, Xianjun; Bigbee, John W; Damaj, M Imad; Gewirtz, David A

    2018-01-01

    Chemotherapy-induced peripheral neuropathy (CIPN), a consequence of peripheral nerve fiber dysfunction or degeneration, continues to be a dose-limiting and debilitating side effect during and/or after cancer chemotherapy. Paclitaxel, a taxane commonly used to treat breast, lung, and ovarian cancers, causes CIPN in 59-78% of cancer patients. Novel interventions are needed due to the current lack of effective CIPN treatments. Our studies were designed to investigate whether nicotine can prevent and/or reverse paclitaxel-induced peripheral neuropathy in a mouse model of CIPN, while ensuring that nicotine will not stimulate lung tumor cell proliferation or interfere with the antitumor properties of paclitaxel. Male C57BL/6J mice received paclitaxel every other day for a total of four injections (8 mg/kg, i.p.). Acute (0.3-0.9 mg/kg, i.p.) and chronic (24 mg/kg per day, s.c.) administration of nicotine respectively reversed and prevented paclitaxel-induced mechanical allodynia. Blockade of the antinociceptive effect of nicotine with mecamylamine and methyllycaconitine suggests that the reversal of paclitaxel-induced mechanical allodynia is primarily mediated by the α 7 nicotinic acetylcholine receptor subtype. Chronic nicotine treatment also prevented paclitaxel-induced intraepidermal nerve fiber loss. Notably, nicotine neither promoted proliferation of A549 and H460 non-small cell lung cancer cells nor interfered with paclitaxel-induced antitumor effects, including apoptosis. Most importantly, chronic nicotine administration did not enhance Lewis lung carcinoma tumor growth in C57BL/6J mice. These data suggest that the nicotinic acetylcholine receptor-mediated pathways may be promising drug targets for the prevention and treatment of CIPN. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

  11. Evaluation of Lercanidipine in Paclitaxel-Induced Neuropathic Pain Model in Rat: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Lekha Saha

    2012-01-01

    Full Text Available Objective. To demonstrate the antinociceptive effect of lercanidipine in paclitaxel-induced neuropathy model in rat. Materials and Methods. A total of 30 rats were divided into five groups of six rats in each group as follows: Gr I: 0.9% NaCl, Gr II: paclitaxel + 0.9% NaCl, Gr III: paclitaxel + lercanidipine 0.5 μg/kg, Gr IV: paclitaxel + lercanidipine 1 μg/kg, and Gr V: paclitaxel + lercanidipine 2.5 μg/kg. Paclitaxel-induced neuropathic pain in rat was produced by single intraperitoneal (i.p. injection of 1 mg/kg of paclitaxel on four alternate days (0, 2, 4, and 6. The tail flick and cold allodynia methods were used for assessing the pain threshold, and the assessments were done on days 0 (before first dose of paclitaxel and on days 7, 14, 21, and 28. Results. There was a significant decrease (P<0.001 in the tail flick and cold allodynia latency in the paclitaxel-alone group from day 14 onward when compared with day 0. In the lercanidipine groups, the decrease in the tail flick and cold allodynia latency was not observed in 1.0 and 2.5 μg/kg groups and it was statistically significant (P<0.01 when compared with paclitaxel-alone group.

  12. Effects of Goshajinkigan, Hachimijiogan, and Rokumigan on Mechanical Allodynia Induced by Paclitaxel in Mice

    Directory of Open Access Journals (Sweden)

    Tsugunobu Andoh

    2014-10-01

    Full Text Available Peripheral neuropathy is a major dose-limiting side effect of the chemotherapeutic agent paclitaxel. This study examined whether the three related traditional herbal formulations, goshajinkigan (GJG; 牛車腎氣丸 Niú Chē Shèn Qì Wán, hachimijiogan (HJG; 八味地黃丸 Bā Wèi Dì Huáng Wán, and rokumigan (RMG; 六味丸 Liù Wèi Wán, would relieve paclitaxel-induced mechanical allodynia in mice. A single intraperitoneal injection of paclitaxel (5 mg/kg induced mechanical allodynia, which peaked on day 14 after injection. On day 14 after paclitaxel injection, oral administration of GJG (0.1-1.0 g/kg produced a significant inhibition of established allodynia, but HJG and RMG did not affect the allodynia. Repeated oral administration of GJG (0.1-1.0 g/kg starting from the day after paclitaxel injection did not affect allodynia development, but significantly inhibited allodynia exacerbation. Repeated oral administration of HJG produced a slight inhibition of allodynia exacerbation, but that of RMG did not. These results suggest that prophylactic administration of GJG is effective in preventing the exacerbation of paclitaxel-induced allodynia. The herbal medicines Plantaginis Semen (車前子 Chē Qián Zǐ and Achyranthis Radix (牛膝 Niú Xī, which are present in GJG but not in HJG, may contribute to the inhibitory action of GJG on the exacerbation of paclitaxel-induced allodynia.

  13. Targeted sequencing reveals low-frequency variants in EPHA genes as markers of paclitaxel-induced peripheral neuropathy.

    OpenAIRE

    Apellániz-Ruiz, Maria; Tejero, Héctor; Inglada-Pérez, Lucía; Sánchez-Barroso, Lara; Gutiérrez-Gutiérrez, Gerardo; Calvo, Isabel; Castelo, Beatriz; Redondo, Andrés; García-Donás, Jesus; Romero-Laorden, Nuria; Sereno, Maria; Merino, María; Currás-Freixes, Maria; Montero-Conde, Cristina; Mancikova, Veronika

    2017-01-01

    PURPOSE: Neuropathy is the dose limiting toxicity of paclitaxel and a major cause for decreased quality of life. Genetic factors have been shown to contribute to paclitaxel neuropathy susceptibility; however, the major causes for inter-individual differences remain unexplained. In this study we identified genetic markers associated with paclitaxel-induced neuropathy through massive sequencing of candidate genes. EXPERIMENTAL DESIGN: We sequenced the coding region of 4 EPHA genes, 5 genes invo...

  14. Bevacizumab Exacerbates Paclitaxel-Induced Neuropathy: A Retrospective Cohort Study.

    Directory of Open Access Journals (Sweden)

    Ayumu Matsuoka

    Full Text Available Bevacizumab (BEV, a humanized anti-vascular endothelial growth factor (VEGF monoclonal antibody, enhances the antitumor effectiveness of paclitaxel (PTX-based chemotherapy in many metastatic cancers. A recent study in mice showed that VEGF receptor inhibitors can interfere with the neuroprotective effects of endogenous VEGF, potentially triggering the exacerbation of PTX-induced neuropathy. In clinical trials, exacerbation of neuropathy in patients who received PTX combined with BEV (PTX+BEV has generally been explained by increased exposure to PTX owing to the extended duration of chemotherapy. We investigated whether the concurrent use of BEV is associated with the exacerbation of PTX-induced neuropathy.Female patients with breast cancer who had received weekly PTX or PTX+BEV from September 2011 through May 2016 were studied retrospectively. PTX-induced neuropathy was evaluated at the same time points (at the 6th and 12th courses of chemotherapy in both cohorts. A multivariate Cox proportional-hazards model was used to assess the independent effect of BEV on the time to the onset of neuropathy.A total of 107 patients (median age, 55 years; range, 32-83 were studied. Sixty-one patients received PTX as adjuvant chemotherapy, 23 received PTX for metastatic disease, and 23 received PTX+BEV for metastatic disease. Peripheral sensory neuropathy was worse in patients who received PTX+BEV than in those who received PTX alone: at the 6th course, Grade 0/1/2/3 = 4/13/4/0 vs. 25/42/6/0 (P = 0.095; at the 12th course, 2/3/11/3 vs. 7/30/23/2 (P = 0.016. At the 12th course, the incidence of Grade 2 or higher neuropathy was significantly higher in patients treated with PTX+BEV than in those treated with PTX alone (74% vs. 40%; P = 0.017. In multivariate analysis, BEV was significantly associated with an increased risk of neuropathy (HR 2.32, 95% CI 1.21-4.44, P = 0.012.The concurrent use of BEV could worsen PTX-induced neuropathy in patients with breast

  15. Rikkunshito prevents paclitaxel-induced peripheral neuropathy through the suppression of the nuclear factor kappa B (NFκB phosphorylation in spinal cord of mice.

    Directory of Open Access Journals (Sweden)

    Junzo Kamei

    Full Text Available Peripheral neuropathy is the major side effect caused by paclitaxel, a microtubule-binding antineoplastic drug. Paclitaxel-induced peripheral neuropathy causes a long-term negative impact on the patient's quality of life. However, the mechanism underlying paclitaxel-induced peripheral neuropathy is still unknown, and there is no established treatment. Ghrelin is known to attenuate thermal hyperalgesia and mechanical allodynia in chronic constriction injury of the sciatic nerve, and inhibit the activation of nuclear factor kappa B (NFκB in the spinal dorsal horn. Rikkunshito (RKT, a kampo medicine, increases the secretion of ghrelin in rodents and humans. Thus, RKT may attenuate paclitaxel-induced peripheral neuropathy by inhibiting phosphorylated NFκB (pNFκB in the spinal cord. We found that paclitaxel dose-dependently induced mechanical hyperalgesia in mice. Paclitaxel increased the protein levels of spinal pNFκB, but not those of spinal NFκB. NFκB inhibitor attenuated paclitaxel-induced mechanical hyperalgesia suggesting that the activation of NFκB mediates paclitaxel-induced hyperalgesia. RKT dose-dependently attenuated paclitaxel-induced mechanical hyperalgesia. Ghrelin receptor antagonist reversed the RKT-induced attenuation of paclitaxel-induced mechanical hyperalgesia. RKT inhibited the paclitaxel-induced increase in the protein levels of spinal pNFκB. Taken together, the present study indicates that RKT exerts an antihyperalgesic effect in paclitaxel-induced neuropathic pain by suppressing the activation of spinal NFκB.

  16. Effect of Xylopic Acid on Paclitaxel-induced Neuropathic pain in rats ...

    African Journals Online (AJOL)

    Xylopic acid, a diterpenoid isolated from the fruits of Xylopia aethiopica has demonstrated analge-sic properties in acute pain models. It was therefore evaluated for its analgesic properties in paclitaxel-induced neuropathic pain, a type of pain difficult to treat clinically. Neuropathic pain was induced in rats by injecting 2 mg ...

  17. Evaluation of Lercanidipine in Paclitaxel-Induced Neuropathic Pain Model in Rat: A Preliminary Study

    OpenAIRE

    Saha, Lekha; Hota, Debasish; Chakrabarti, Amitava

    2012-01-01

    Objective. To demonstrate the antinociceptive effect of lercanidipine in paclitaxel-induced neuropathy model in rat. Materials and Methods. A total of 30 rats were divided into five groups of six rats in each group as follows: Gr I: 0.9% NaCl, Gr II: paclitaxel + 0.9% NaCl, Gr III: paclitaxel + lercanidipine 0.5 μg/kg, Gr IV: paclitaxel + lercanidipine 1 μg/kg, and Gr V: paclitaxel + lercanidipine 2.5 μg/kg. Paclitaxel-induced neuropathic pain in rat was produced by single intraperitoneal (i....

  18. Low Levels of NDRG1 in Nerve Tissue Are Predictive of Severe Paclitaxel-Induced Neuropathy.

    Directory of Open Access Journals (Sweden)

    Raghav Sundar

    Full Text Available Sensory peripheral neuropathy caused by paclitaxel is a common and dose limiting toxicity, for which there are currently no validated predictive biomarkers. We investigated the relationship between the Charcot-Marie-Tooth protein NDRG1 and paclitaxel-induced neuropathy.Archived mammary tissue specimen blocks of breast cancer patients who received weekly paclitaxel in a single centre were retrieved and NDRG1 immunohistochemistry was performed on normal nerve tissue found within the sample. The mean nerve NDRG1 score was defined by an algorithm based on intensity of staining and percentage of stained nerve bundles. NDRG1 scores were correlated with paclitaxel induced neuropathy.111 patients were studied. 17 of 111 (15% developed severe paclitaxel-induced neuropathy. The mean nerve NDRG1 expression score was 5.4 in patients with severe neuropathy versus 7.7 in those without severe neuropathy (p = 0.0019. A Receiver operating characteristic (ROC curve analysis of the mean nerve NDRG1 score revealed an area under the curve of 0.74 (p = 0.0013 for the identification of severe neuropathy, with a score of 7 being most discriminative. 13/54 (24% subjects with an NDRG1 score 7 (p = 0.017.Low NDRG1 expression in nerve tissue present within samples of surgical resection may identify subjects at risk for severe paclitaxel-induced neuropathy. Since nerve biopsies are not routinely feasible for patients undergoing chemotherapy for early breast cancer, this promising biomarker strategy is compatible with current clinical workflow.

  19. Quetiapine reverse paclitaxel-induced neuropathic pain in mice: Role of Alpha2- adrenergic receptors

    Directory of Open Access Journals (Sweden)

    Alireza Abed

    2017-11-01

    Full Text Available Objective(s: Paclitaxel-induced peripheral neuropathy is a common adverse effect of cancer chemo -therapy. This neuropathy has a profound impact on quality of life and patient’s survival. Preventing and treating paclitaxel-induced peripheral neuropathy is a major concern. First- and second-generation antipsychotics have shown analgesic effects both in humans and animals. Quetiapine is a novel atypical antipsychotic with low propensity to induce extrapyramidal or hyperprolactinemia side effects. The present study was designed to investigate the effects of quetiapine on the development and expression of neuropathic pain induced by paclitaxel in mice and the role of α2-adrenoceptors on its antinociception. Materials and Methods: Paclitaxel (2 mg/kg IP was injected for five consecutive days which resulted in thermal hyperalgesia and mechanical and cold allodynia. Results: Early administration of quetiapine from the 1st day until the 5th day (5, 10, and 15 mg/kg PO did not affect thermal, mechanical, and cold stimuli and could not prevent the development of neuropathic pain. In contrast, when quetiapine (10 and 15 mg/kg PO administration was started on the 6th day after the first paclitaxel injections, once the model had been established, and given daily until the 10th day, heat hyperalgesia and mechanical and cold allodynia were significantly attenuated. Also, the effect of quetiapine on heat hyperalgesia was reversed by pretreatment with yohimbine, as an alpha-2 adrenergic receptor antagonist. Conclusion: These results indicate that quetiapine, when administered after nerve injury can reverse the expression of neuropathic pain. Also, we conclude that α2-adrenoceptors participate in the antinociceptive effects of quetiapine.

  20. Minoxidil is a potential neuroprotective drug for paclitaxel-induced peripheral neuropathy

    Science.gov (United States)

    Chen, Yi-Fan; Chen, Li-Hsien; Yeh, Yu-Min; Wu, Pei-Ying; Chen, Yih-Fung; Chang, Lian-Yun; Chang, Jang-Yang; Shen, Meng-Ru

    2017-01-01

    Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of cancer treatment. No medication has been shown to be effective in the treatment of CIPN. This study aims to integrate the image-based high-content screening, mouse behavior models and mechanistic cell-based assays to discover potential neuroprotective drugs. Among screened compounds, minoxidil showed the most potent neuroprotective effect against paclitaxel, with regard to neurite outgrowth of dorsal root ganglia (DRG). Minoxidil protected mice from thermal insensitivity and alleviated mechanical allodynia in paclitaxel-treated mice. The ultrastructure and quantified G-ratio of myelin integrity of sciatic nerve tissues supported the observations in mouse behavioral tests. The mechanistic study on DRG neurons suggested that minoxidil suppressed neuroinflammation and remodeled the dysregulation of intracellular calcium homeostasis provoked by paclitaxel. Importantly, minoxidil showed a synergistic anti-tumor effect with paclitaxel both in tumor xenograft models of cervical and breast cancer. Interestingly, the quantitative assays on hair length and hair growth both exhibited that minoxidil significantly improved the hair quality after chemotherapy. Since minoxidil is a drug approved by the Food and Drug Administration (FDA), the safety and biocompatibility are well documented. The immediate next step is to launch an early-stage clinical trial intending to prevent CIPN by minoxidil. PMID:28349969

  1. Evidence that spinal astrocytes but not microglia contribute to the pathogenesis of paclitaxel-induced painful neuropathy

    OpenAIRE

    Zhang, Haijun; Yoon, Seo-Yeon; Zhang, Hongmei; Dougherty, Patrick M.

    2012-01-01

    Paclitaxel often induces persistent painful neuropathy as its most common treatment limiting side effect. Little is known concerning the underlying mechanisms. Given the prominent role of glial cells in many types of neuropathic pain, we investigated here the morphological and functional changes of spinal astrocytes and microglia in a rat model of paclitaxel-induced neuropathy. Immunohistochemistry, western blotting and real-time polymerase chain reaction (rt-PCR) were performed with samples ...

  2. Lansoprazole induces sensitivity to suboptimal doses of paclitaxel in human melanoma.

    Science.gov (United States)

    Azzarito, Tommaso; Venturi, Giulietta; Cesolini, Albino; Fais, Stefano

    2015-01-28

    Tumor acidity is now considered an important determinant of drug-resistance and tumor progression, and anti-acidic approaches, such as Proton Pump inhibitors (PPIs), have demonstrated promising antitumor and chemo-sensitizing efficacy. The main purpose of the present study was to evaluate the possible PPI-induced sensitization of human melanoma cells to Paclitaxel (PTX). Our results show that PTX and the PPI Lansoprazole (LAN) combination was extremely efficient against metastatic melanoma cells, as compared to the single treatments, both in vitro and in vivo. We also showed that acidity plays an important role on the anti-tumor activity of these drugs, being detrimental for PTX activity, while crucial for the synergistic effect of PTX following pretreatment with LAN, due to its nature of pro-drug needing protonation for a full activation. We obtained straightforward results in a human melanoma xenograft model combining well tolerated LAN doses with suboptimal and poorly toxic doses of PTX. With this study we provide a clear evidence that the PPI LAN may be included in new combined therapy of human melanoma together with low doses of PTX. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  3. Effect of kamikihito (TJ-137) on paclitaxel-induced olfactory neuropathy in vivo

    International Nuclear Information System (INIS)

    Yamamoto, Junpei

    2012-01-01

    A Kampo product, kamikihito (product name code: TJ-137), has ingredients that promote nerve growth. Paclitaxel, a cancer chemotherapeutic agent, is toxic to olfactory nerve cells in vivo. We found that TJ-137 is effective in reducing paclitaxel induced olfactory neuropathy in vivo. Female 7-week-old Bulb/c mice were fed food containing TJ-137, or control food, for 14 days before and after intravenous paclitaxel administration. 201 Tl uptake in nasal turbinates of TJ-137 treated mice (n=8) and control mice (n=9) was assessed by gamma spectrometry 6 hrs after nasal administration of 201 Tl. The epithelial changes in the nasal turbinates of mice were assessed by H and E and immunohistochemical staining for the olfactory marker protein (OMP). The accumulation of the neuronal tracer (Dextran tetramethylrhodamine) in the olfactory bulb was assessed in frozen sections of mice 48 hrs after nasal administration of the tracer. The epithelium of nasal turbinates of TJ-137 treated mice was less injured than that of the control mice after paclitaxel administration. The nasal epithelium was significantly thicker in TJ-137 treated mice compared to control mice (P=0.019). The accumulation of the neuronal tracer in the olfactory bulb was higher in the TJ-137 treated mice compared to controls. 201 Tl uptake per weight in nasal turbinate of TJ-137 treated mice was significantly higher than that of control mice (P=0.008). Pre-medication with TJ-137 (kamikihito) was effective in increasing olfactory nerve viability after paclitaxel administration in vivo. (author)

  4. Assessment of paclitaxel induced sensory polyneuropathy with "Catwalk" automated gait analysis in mice.

    Directory of Open Access Journals (Sweden)

    Petra Huehnchen

    Full Text Available Neuropathic pain as a symptom of sensory nerve damage is a frequent side effect of chemotherapy. The most common behavioral observation in animal models of chemotherapy induced polyneuropathy is the development of mechanical allodynia, which is quantified with von Frey filaments. The data from one study, however, cannot be easily compared with other studies owing to influences of environmental factors, inter-rater variability and differences in test paradigms. To overcome these limitations, automated quantitative gait analysis was proposed as an alternative, but its usefulness for assessing animals suffering from polyneuropathy has remained unclear. In the present study, we used a novel mouse model of paclitaxel induced polyneuropathy to compare results from electrophysiology and the von Frey method to gait alterations measured with the Catwalk test. To mimic recently improved clinical treatment strategies of gynecological malignancies, we established a mouse model of dose-dense paclitaxel therapy on the common C57Bl/6 background. In this model paclitaxel treated animals developed mechanical allodynia as well as reduced caudal sensory nerve action potential amplitudes indicative of a sensory polyneuropathy. Gait analysis with the Catwalk method detected distinct alterations of gait parameters in animals suffering from sensory neuropathy, revealing a minimized contact of the hind paws with the floor. Treatment of mechanical allodynia with gabapentin improved altered dynamic gait parameters. This study establishes a novel mouse model for investigating the side effects of dose-dense paclitaxel therapy and underlines the usefulness of automated gait analysis as an additional easy-to-use objective test for evaluating painful sensory polyneuropathy.

  5. No significant role for beta tubulin mutations and mismatch repair defects in ovarian cancer resistance to paclitaxel/cisplatin

    International Nuclear Information System (INIS)

    Mesquita, Bárbara; Veiga, Isabel; Pereira, Deolinda; Tavares, Ana; Pinto, Isabel M; Pinto, Carla; Teixeira, Manuel R; Castedo, Sérgio

    2005-01-01

    The mechanisms of chemoresistance in ovarian cancer patients remain largely to be elucidated. Paclitaxel/cisplatin combination is the standard chemotherapeutic treatment for this disease, although some patients do not respond to therapy. Our goals were to investigate whether TUBB mutations and mismatch repair defects underlie paclitaxel and cisplatin resistance. Thirty-four patients with primary ovarian carcinomas (26 serous and eight clear cell carcinomas) treated with paclitaxel/cisplatin were analysed. TUBB exon 4 was analysed by nested PCR after a first round PCR using intronic primers. Microsatellite analysis was performed with the quasimonomorphic markers BAT 26 and BAT 34. Twenty-two of the 34 ovarian cancers (64.7%) presented residual tumour after surgery, seven of which (7/22; 31.8%) were shown to be chemoresistant (five serous and two clear cell tumours). Sequence analysis did not find any mutation in TUBB exon 4. Microsatellite instability was not detected in any of the ovarian carcinomas. We conclude that TUBB exon 4 mutations and mismatch repair defects do not play a significant role in paclitaxel/cisplatin resistance

  6. Investigation of 3′-debenzoyl-3′-(3-([124I]-iodobenzoyl))paclitaxel analog as a radio-tracer to study multidrug resistance in vivo

    International Nuclear Information System (INIS)

    Sajjad, M.; Riaz, U.; Yao, R.; Bernacki, R.J.; Abouzied, M.; Erb, D.A.; Chaudhary, N.D.; Veith, J.M.; Georg, G.I.; Nabi, H.A.

    2012-01-01

    A study was carried out to identify a suitable radioactive paclitaxel analog and to use it to investigate tumor multidrug resistance in vivo. 3′-Debenzoyl-3′-(3-([ 124 I]-iodobenzoyl))paclitaxel was prepared by aromatic iodination of 3′-debenzoyl-3′-(3-trimethylstannylbenzoyl)paclitaxel. Uptake of the labeled paclitaxel analog in nude mice bearing tumor with the paclitaxel sensitive cancer cell lines MCF7 and MDA-435/LCC6(WT), and multidrug resistant cell lines NCI/ADR-RES and MDA-435/LCC6(MDR), was studied. There was no difference in drug level between the sensitive and resistant MDA-435/LCC6 tumors at 6 h post-injection. However, at 6 h, there was a significant increase in drug level for the MCF7 tumor as compared with the NCI/ADR-RES tumor, presumably due to increased drug retention. At 24 h, drug uptake/retention was significantly higher in both sensitive tumor cell lines as compared to their drug resistant counterparts. Pretreatment of mice with MDR transport modulators, Cyclosporine or tRA 96029, did not increase the level of labeled paclitaxel analog in the drug resistant MDA-435/LCC6(MDR) tumor. On the other hand, at 24 h Cyclosporine apparently increased analog level in the drug sensitive MDA-435/LCC6(WT) tumor, aiding drug imaging studies. - Highlights: ► 3′-Debenzoyl-3′-(3-iodobenzoyl)paclitaxel cytotoxicity was comparable to paclitaxel. ► 3′-Debenzoyl-3′-(3-([ 124 I]-iodobenzoyl)paclitaxel was synthesized. ► Uptake of the drug was higher in sensitive tumor compared to the resistant tumor. ► The Pgp-modulators had a positive effect on drug-sensitive tumor. ► The sensitive tumor was visible in images obtained using micoPET.

  7. Neurosteroid 3α-androstanediol efficiently counteracts paclitaxel-induced peripheral neuropathy and painful symptoms.

    Directory of Open Access Journals (Sweden)

    Laurence Meyer

    Full Text Available Painful peripheral neuropathy belongs to major side-effects limiting cancer chemotherapy. Paclitaxel, widely used to treat several cancers, induces neurological symptoms including burning pain, allodynia, hyperalgesia and numbness. Therefore, identification of drugs that may effectively counteract paclitaxel-induced neuropathic symptoms is crucial. Here, we combined histopathological, neurochemical, behavioral and electrophysiological methods to investigate the natural neurosteroid 3α-androstanediol (3α-DIOL ability to counteract paclitaxel-evoked peripheral nerve tissue damages and neurological symptoms. Prophylactic or corrective 3α-DIOL treatment (4 mg/kg/2 days prevented or suppressed PAC-evoked heat-thermal hyperalgesia, cold-allodynia and mechanical allodynia/hyperalgesia, by reversing to normal, decreased thermal and mechanical pain thresholds of PAC-treated rats. Electrophysiological studies demonstrated that 3α-DIOL restored control values of nerve conduction velocity and action potential peak amplitude significantly altered by PAC-treatment. 3α-DIOL also repaired PAC-induced nerve damages by restoring normal neurofilament-200 level in peripheral axons and control amount of 2',3'-cyclic-nucleotide-3'-phosphodiesterase in myelin sheaths. Decreased density of intraepidermal nerve fibers evoked by PAC-therapy was also counteracted by 3α-DIOL treatment. More importantly, 3α-DIOL beneficial effects were not sedation-dependent but resulted from its neuroprotective ability, nerve tissue repairing capacity and long-term analgesic action. Altogether, our results showing that 3α-DIOL efficiently counteracted PAC-evoked painful symptoms, also offer interesting possibilities to develop neurosteroid-based strategies against chemotherapy-induced peripheral neuropathy. This article shows that the prophylactic or corrective treatment with 3α-androstanediol prevents or suppresses PAC-evoked painful symptoms and peripheral nerve dysfunctions in

  8. Involvement of the chemokine CCL3 and the purinoceptor P2X7 in the spinal cord in paclitaxel-induced mechanical allodynia

    OpenAIRE

    Ochi-ishi, Ryutaro; Nagata, Kenichiro; Inoue, Tomoyuki; Tozaki-Saitoh, Hidetoshi; Tsuda, Makoto; Inoue, Kazuhide

    2014-01-01

    Background Paclitaxel is an effective chemotherapeutic agent widely used for the treatment of solid tumors. The major dose-limiting toxicity of paclitaxel is peripheral neuropathy. The mechanisms underlying the development and maintenance of paclitaxel-induced peripheral neuropathy are still unclear, and there are no currently established effective treatments. Accumulating evidence in models of neuropathic pain in which peripheral nerves are lesioned has implicated spinal microglia and chemok...

  9. Re-expression of ARHI (DIRAS3) induces autophagy in breast cancer cells and enhances the inhibitory effect of paclitaxel

    International Nuclear Information System (INIS)

    Zou, Chun-Fang; Yu, Yinhua; Jia, Luoqi; Jin, Hongyan; Yao, Ming; Zhao, Naiqing; Huan, Jin; Lu, Zhen; Bast, Robert C Jr; Feng, Youji

    2011-01-01

    ARHI is a Ras-related imprinted gene that inhibits cancer cell growth and motility. ARHI is downregulated in the majority of breast cancers, and loss of its expression is associated with its progression from ductal carcinoma in situ (DCIS) to invasive disease. In ovarian cancer, re-expression of ARHI induces autophagy and leads to autophagic death in cell culture; however, ARHI re-expression enables ovarian cancer cells to remain dormant when they are grown in mice as xenografts. The purpose of this study is to examine whether ARHI induces autophagy in breast cancer cells and to evaluate the effects of ARHI gene re-expression in combination with paclitaxel. Re-expression of ARHI was achieved by transfection, by treatment with trichostatin A (TSA) or by a combination of TSA and 5-aza-2'-deoxycytidine (DAC) in breast cancer cell cultures and by liposomal delivery of ARHI in breast tumor xenografts. ARHI re-expression induces autophagy in breast cancer cells, and ARHI is essential for the induction of autophagy. When ARHI was re-expressed in breast cancer cells treated with paclitaxel, the growth inhibitory effect of paclitaxel was enhanced in both the cell culture and the xenografts. Although paclitaxel alone did not induce autophagy in breast cancer cells, it enhanced ARHI-induced autophagy. Conversely, ARHI re-expression promoted paclitaxel-induced apoptosis and G2/M cell cycle arrest. ARHI re-expression induces autophagic cell death in breast cancer cells and enhances the inhibitory effects of paclitaxel by promoting autophagy, apoptosis, and G2/M cell cycle arrest

  10. Effect of flavonol and its dimethoxy derivatives on paclitaxel-induced peripheral neuropathy in mice.

    Science.gov (United States)

    Sayeli, Vijaykumar; Nadipelly, Jagan; Kadhirvelu, Parimala; Cheriyan, Binoy Varghese; Shanmugasundaram, Jaikumar; Subramanian, Viswanathan

    2018-04-13

    Peripheral neuropathy is the dose limiting side effect of many anticancer drugs. Flavonoids exhibit good antinociceptive effect in animal models. Their efficacy against different types of nociception has been documented. The present study investigated the effect of flavonol (3-hydroxy flavone), 3',4'-dimethoxy flavonol, 6,3'-dimethoxy flavonol, 7,2'-dimethoxy flavonol and 7,3'-dimethoxy flavonol against paclitaxel-induced peripheral neuropathy in mice. A single dose of paclitaxel (10 mg/kg, i.p.) was administered to induce peripheral neuropathy in mice and the manifestations of peripheral neuropathy such as tactile allodynia, cold allodynia and thermal hyperalgesia were assessed 24 h later by employing Von Frey hair aesthesiometer test, acetone bubble test and hot water tail immersion test, respectively. The test compounds were prepared as a suspension in 0.5% carboxymethyl cellulose and were administered s.c. in various doses (25, 50, 100 and 200 mg/kg). The above behavioral responses were assessed prior to and 30 min after drug treatment. In addition, the effect of test compounds on proinflammatory cytokines like tumor necrosis factor-alpha (TNF-α), interleukin-1-beta (IL-1β) and free radicals was investigated by using suitable in vitro assays. A dose-dependent attenuation of tactile allodynia, cold allodynia and thermal hyperalgesia was evidenced in mice treated with flavonol derivatives. The test compounds inhibited TNF-α, IL-1β and free radicals in a concentration-dependent manner. These results revealed that flavonol and its dimethoxy derivatives ameliorated the manifestations of paclitaxel-induced peripheral neuropathy in mice. The inhibition of proinflammatory cytokines and free radicals could contribute to this beneficial effect.

  11. Suberoylanilide hydroxamic acid sensitizes neuroblastoma to paclitaxel by inhibiting thioredoxin-related protein 14-mediated autophagy.

    Science.gov (United States)

    Zhen, Zijun; Yang, Kaibin; Ye, Litong; You, Zhiyao; Chen, Rirong; Liu, Ying; He, Youjian

    2017-07-01

    Paclitaxel is not as effective for neuroblastoma as most of the front-line chemotherapeutics due to drug resistance. This study explored the regulatory mechanism of paclitaxel-associated autophagy and potential solutions to paclitaxel resistance in neuroblastoma. The formation of autophagic vesicles was detected by scanning transmission electron microscopy and flow cytometry. The autophagy-associated proteins were assessed by western blot. Autophagy was induced and the autophagy-associated proteins LC3-I, LC3-II, Beclin 1, and thioredoxin-related protein 14 (TRP14), were found to be upregulated in neuroblastoma cells that were exposed to paclitaxel. The inhibition of Beclin 1 or TRP14 by siRNA increased the sensitivity of the tumor cells to paclitaxel. In addition, Beclin 1-mediated autophagy was regulated by TRP14. Furthermore, the TRP14 inhibitor suberoylanilide hydroxamic acid (SAHA) downregulated paclitaxel-induced autophagy and enhanced the anticancer effects of paclitaxel in normal control cancer cells but not in cells with upregulated Beclin 1 and TRP14 expression. Our findings showed that paclitaxel-induced autophagy in neuroblastoma cells was regulated by TRP14 and that SAHA could sensitize neuroblastoma cells to paclitaxel by specifically inhibiting TRP14. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  12. [A paclitaxel-resistant case of recurrent breast cancer responded to combination therapy of capecitabine and trastuzumab].

    Science.gov (United States)

    Marutaka, Masahito; Suguri, Takayasu; Miyake, Mikio; Yoshimura, Kouichi

    2005-12-01

    The patient was a 72-year-old female. Under the supervision of her former doctor, this patient had an operation and adjuvant chemotherapy for progressive breast cancer. During the following period, local recurrence of breast cancer and pulmonary lymphopathia developed. Although medication with paclitaxel was attempted, the focus was resistant to this treatment, and metastasis to the brain was also observed. Due to the dyscrasia above, the patient had difficulty breathing and became bedridden. Subsequently, combination treatment of capecitabine and trastuzumab was attempted. As a result,metastasis in the brain and pulmonary lymphopathia were improved. The patient recovered enough to be discharged at one time. However, his condition took a turn for the worse after the interruption of the combination treatment by a side effect. In conclusion, the combination treatment of capecitabine and trastuzumab is thought to be effective for non-responders to paclitaxel.

  13. Genomic signatures for paclitaxel and gemcitabine resistance in breast cancer derived by machine learning.

    Science.gov (United States)

    Dorman, Stephanie N; Baranova, Katherina; Knoll, Joan H M; Urquhart, Brad L; Mariani, Gabriella; Carcangiu, Maria Luisa; Rogan, Peter K

    2016-01-01

    Increasingly, the effectiveness of adjuvant chemotherapy agents for breast cancer has been related to changes in the genomic profile of tumors. We investigated correspondence between growth inhibitory concentrations of paclitaxel and gemcitabine (GI50) and gene copy number, mutation, and expression first in breast cancer cell lines and then in patients. Genes encoding direct targets of these drugs, metabolizing enzymes, transporters, and those previously associated with chemoresistance to paclitaxel (n = 31 genes) or gemcitabine (n = 18) were analyzed. A multi-factorial, principal component analysis (MFA) indicated expression was the strongest indicator of sensitivity for paclitaxel, and copy number and expression were informative for gemcitabine. The factors were combined using support vector machines (SVM). Expression of 15 genes (ABCC10, BCL2, BCL2L1, BIRC5, BMF, FGF2, FN1, MAP4, MAPT, NFKB2, SLCO1B3, TLR6, TMEM243, TWIST1, and CSAG2) predicted cell line sensitivity to paclitaxel with 82% accuracy. Copy number profiles of 3 genes (ABCC10, NT5C, TYMS) together with expression of 7 genes (ABCB1, ABCC10, CMPK1, DCTD, NME1, RRM1, RRM2B), predicted gemcitabine response with 85% accuracy. Expression and copy number studies of two independent sets of patients with known responses were then analyzed with these models. These included tumor blocks from 21 patients that were treated with both paclitaxel and gemcitabine, and 319 patients on paclitaxel and anthracycline therapy. A new paclitaxel SVM was derived from an 11-gene subset since data for 4 of the original genes was unavailable. The accuracy of this SVM was similar in cell lines and tumor blocks (70-71%). The gemcitabine SVM exhibited 62% prediction accuracy for the tumor blocks due to the presence of samples with poor nucleic acid integrity. Nevertheless, the paclitaxel SVM predicted sensitivity in 84% of patients with no or minimal residual disease. Copyright © 2015 Federation of European Biochemical Societies

  14. Prevention of Paclitaxel-induced allodynia by Minocycline: Effect on loss of peripheral nerve fibers and infiltration of macrophages in rats

    Directory of Open Access Journals (Sweden)

    Xin Wen-Jun

    2010-11-01

    Full Text Available Abstract Background Although paclitaxel is a frontline antineoplastic agent for treatment of solid tumors, the paclitaxel-evoked pain syndrome is a serious problem for patients. There is currently no valid drug to prevent or treat the paclitaxel-induced allodynia, partly due to lack of understanding regarding the cellular mechanism. Studies have shown that minocycline, an inhibitor of microglia/macrophage, prevented neuropathic pain and promoted neuronal survival in animal models of neurodegenerative disease. Recently, Cata et al also reported that minocycline inhibited allodynia induced by low-dose paclitaxel (2 mg/kg in rats, but the mechanism is still unclear. Results Here, we investigate by immunohistochemistry the change of intraepidermal nerve fiber (IENF in the hind paw glabrous skin, expression of macrophage and activating transcription factor 3 (ATF3 in DRG at different time points after moderate-dose paclitaxel treatment (cumulative dose 24 mg/kg; 3 × 8 mg/kg in rats. Moreover, we observe the effect of minocycline on the IENF, macrophages and ATF3. The results showed that moderate-dose paclitaxel induced a persisted, gradual mechanical allodynia, which was accompanied by the loss of IENF in the hind paw glabrous skin and up-regulation of macrophages and ATF3 in DRG in rats. The expressions of ATF3 mainly focus on the NF200-positive cells. More importantly, we observed that pretreatment of minocycline at dose of 30 mg/kg or 50 mg/kg, but not 5 mg/kg, prevented paclitaxel-evoked allodynia. The evidence from immunohistochemistry showed that 30 mg/kg minocycline rescued the degeneration of IENF, attenuated infiltration of macrophages and up-regulation of ATF3 induced by paclitaxel treatment in rats. Conclusions Minocycline prevents paclitaxel-evoked allodynia, likely due to its inhibition on loss of IENF, infiltration of macrophages and up-regulation of ATF3 in rats. The finding might provide potential target for preventing paclitaxel-induced

  15. MDR1 siRNA loaded hyaluronic acid-based CD44 targeted nanoparticle systems circumvent paclitaxel resistance in ovarian cancer

    Science.gov (United States)

    Yang, Xiaoqian; Lyer, Arun K.; Singh, Amit; Choy, Edwin; Hornicek, Francis J.; Amiji, Mansoor M.; Duan, Zhenfeng

    2015-02-01

    Development of multidrug resistance (MDR) is an almost universal phenomenon in patients with ovarian cancer, and this severely limits the ultimate success of chemotherapy in the clinic. Overexpression of the MDR1 gene and corresponding P-glycoprotein (Pgp) is one of the best known MDR mechanisms. MDR1 siRNA based strategies were proposed to circumvent MDR, however, systemic, safe, and effective targeted delivery is still a major challenge. Cluster of differentiation 44 (CD44) targeted hyaluronic acid (HA) based nanoparticle has been shown to successfully deliver chemotherapy agents or siRNAs into tumor cells. The goal of this study is to evaluate the ability of HA-PEI/HA-PEG to deliver MDR1 siRNA and the efficacy of the combination of HA-PEI/HA-PEG/MDR1 siRNA with paclitaxel to suppress growth of ovarian cancer. We observed that HA-PEI/HA-PEG nanoparticles can efficiently deliver MDR1 siRNA into MDR ovarian cancer cells, resulting in down-regulation of MDR1 and Pgp expression. Administration of HA-PEI/HA-PEG/MDR1 siRNA nanoparticles followed by paclitaxel treatment induced a significant inhibitory effect on the tumor growth, decreased Pgp expression and increased apoptosis in MDR ovarian cancer mice model. Our findings suggest that CD44 targeted HA-PEI/HA-PEG/MDR1 siRNA nanoparticles can serve as a therapeutic tool with great potentials to circumvent MDR in ovarian cancer.

  16. A simple reduction-sensitive micelles co-delivery of paclitaxel and dasatinib to overcome tumor multidrug resistance

    Directory of Open Access Journals (Sweden)

    Li J

    2017-11-01

    Full Text Available Jun Li,1,* Ruitong Xu,2,* Xiao Lu,3 Jing He,1 Shidai Jin1 1Department of Medical Oncology, 2Department of General Practice, The First Affiliated Hospital with Nanjing Medical University, Nanjing, 3Department of Medical Oncology, Changshu No 1 People’s Hospital, Changshu, People’s Republic of China *These authors contributed equally to this work Abstract: Multidrug resistance (MDR is one of the major obstacles in successful chemotherapy. The combination of chemotherapy drugs and multidrug-resistant reversing agents for treating MDR tumor is a good strategy to overcome MDR. In this work, we prepared the simple redox-responsive micelles based on mPEG-SS-C18 as a co-delivery system to load the paclitaxel (PTX and dasatinib (DAS for treatment of MCF-7/ADR cells. The co-loaded micelles had a good dispersity and a spherical shape with a uniform size distribution, and they could quickly disassemble and rapidly release drugs under the reduction environment. Compared with MCF-7 cells, the DAS and PTX co-loaded redox-sensitive micelle (SS-PDNPs showed stronger cytotoxicity and a more improving intracellular drug concentration than other drug formulations in MCF-7/ADR cells. In summary, the results suggested that the simple co-delivery micelles of PTX and DAS possessed significant potential to overcome drug resistance in cancer therapy. Keywords: redox responsive, overcoming multidrug resistant, co-delivery, paclitaxel, dasatinib 

  17. CYP3A4*22 genotype and systemic exposure affect paclitaxel-induced neurotoxicity

    NARCIS (Netherlands)

    A.J.M. de Graan (Anne-Joy); L. Elens (Laure); J.A. Sprowl (Jason); A. Sparreboom (Alex); L.E. Friberg (Lena); B. van der Holt (Bronno); P.J. de Raaf (Pleun); P. de Bruijn (Peter); F.K. Engels (Frederike); F.A.L.M. Eskens (Ferry); E.A.C. Wiemer (Erik); J. Verweij (Jaap); A.H.J. Mathijssen (Ron); R.H.N. van Schaik (Ron)

    2013-01-01

    textabstractPurpose: Paclitaxel is used for the treatment of several solid tumors and displays a high interindividual variation in exposure and toxicity. Neurotoxicity is one of the most prominent side effects of paclitaxel. This study explores potential predictive pharmacokinetic and

  18. Resistance to first line platinum paclitaxel chemotherapy in serous epithelial ovarian cancer

    DEFF Research Database (Denmark)

    Steffensen, Karina Dahl; Smoter, Marta; Waldstrøm, Marianne

    2014-01-01

    of sensitivity to platinum/paclitaxel treatment. The primary aim of the study was to investigate whether ERCC1 and Tau protein expression correlates with patient outcome in newly diagnosed epithelial ovarian cancer (EOC) patients. Formalin-fixed, paraffin-embedded tissue sections from 227 newly diagnosed EOC...

  19. Self-assembly PEGylation assists SLN-paclitaxel delivery inducing cancer cell apoptosis upon internalization.

    Science.gov (United States)

    Arranja, Alexandra; Gouveia, Luís F; Gener, Petra; Rafael, Diana F; Pereira, Carolina; Schwartz, Simó; Videira, Mafalda A

    2016-03-30

    In past years, a considerable progress has been made in the conversion of conventional chemotherapy into potent and safe nanomedicines. The ultimate goal is to improve the therapeutic window of current chemotherapeutics by reducing systemic toxicities and to deliver higher concentrations of the chemotherapeutic agents to malignant cells. In this work, we report that PEGylation of the nanocarriers increases drug intracellular bioavailability leading therefore to higher therapeutic efficacy. The surface of the already patented solid lipid nanoparticles (SLN) loaded with paclitaxel (SLN-PTX) was coated with a PEG layer (SLN-PTX_PEG) through an innovative process to provide stable and highly effective nanoparticles complying with the predefined pharmaceutical quality target product profile. We observed that PEGylation not only stabilizes the SLN, but also modulates their cellular uptake kinetics. As a consequence, the intracellular concentration of chemotherapeutics delivered by SLN-PTX_PEG increases. This leads to the increase of efficacy and thus it is expected to significantly circumvent cancer cell resistance and increase patient survival and cure. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Paclitaxel Injection

    Science.gov (United States)

    (pak'' li tax' el)Paclitaxel injection must be given in a hospital or medical facility under the supervision of a doctor who is experienced in giving chemotherapy medications for cancer.Paclitaxel injection may cause a large decrease in the number of white blood cells (a type of blood cell ...

  1. Sustained platelet-sparing effect of weekly low dose paclitaxel allows effective, tolerable delivery of extended dose dense weekly carboplatin in platinum resistant/refractory epithelial ovarian cancer

    Directory of Open Access Journals (Sweden)

    Blagden Sarah

    2011-07-01

    Full Text Available Abstract Background Platinum agents have shown demonstrable activity in the treatment of patients with platinum resistant, recurrent ovarian cancer when delivered in a "dose-dense" fashion. However, the development of thrombocytopenia limits the weekly administration of carboplatin to no greater than AUC 2. Paclitaxel has a well-described platelet sparing effect however its use to explicitly provide thromboprotection in the context of dose dense carboplatin has not been explored. Methods We treated seven patients with platinum resistant ovarian cancer who had previously received paclitaxel or who had developed significant peripheral neuropathy precluding the use of further full dose weekly paclitaxel. Results We were able to deliver carboplatin AUC 3 and paclitaxel 20 mg/m2 with no thrombocytopenia or worsening of neuropathic side-effects, and with good activity. Conclusions We conclude that this regimen may be feasible and active, and could be formally developed as a "platinum-focussed dose-dense scaffold" into which targeted therapies that reverse platinum resistance can be incorporated, and merits further evaluation.

  2. Paclitaxel-induced hypothermia and hypoperfusion increase breast cancer metastasis and angiogenesis in mice

    Science.gov (United States)

    Ami, Nozomi; Sato, Hideki; Hayakawa, Yoshihiro

    2018-01-01

    Housing temperature has been shown to influence thermoregulation and behavior of preclinical cancer models; and anti-cancer drugs typically reduce peripheral blood flow and body temperature. In the present study, the effects of paclitaxel (PTX)-induced reduction of body temperature and peripheral blood flow on metastatic 4T1 breast cancer was investigated in a mouse model and the modification of these effects by thermoneutral temperature was also assessed. A single dose of PTX decreased the body temperature and peripheral blood flow in mice housed at a standard temperature (23°C). Furthermore, although lung metastasis and angiogenesis of inoculated 4T1 cells increased in mice pretreated with PTX, mice housed at a thermoneutral temperature (30°C) could compensate their body temperature and peripheral blood flow compared with control mice, and also suppressed 4T1 angiogenesis and metastasis to lung. The present results imply that maintenance of body temperature or efficient energy supply for thermogenesis may prevent tumor relapse or metastasis after chemotherapy. PMID:29434941

  3. Paclitaxel Induced MDS and AML: A Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    Udit Bhaskar Bhatnagar

    2016-01-01

    Full Text Available Therapy related acute myelogenous leukemia (AML and myelodysplastic syndromes (MDS have been classically linked to alkylating agents and topoisomerase inhibitors. They constitute about 1% of all AMLs. There is less evidence on association of taxanes (paclitaxel and docetaxel with these myeloid neoplasms. We present a case of paclitaxel therapy related acute myelogenous leukemia after treatment of endometrial cancer with a regimen containing paclitaxel and carboplatin. A 63-year-old female underwent surgery followed by a total of 6 cycles of chemotherapy with carboplatin and paclitaxel. Six months after last cycle of chemotherapy, she was diagnosed with myelodysplastic syndrome with refractory anemia and excess blasts. Six weeks later, she had worsening anemia and thrombocytopenia which prompted a bone marrow biopsy which revealed acute myelomonocytic leukemia. A thorough literature review revealed 12 other case reports where taxanes have been implicated in the development of therapy related myeloid neoplasm. Based on the timeline of events in our patient, paclitaxel is the likely culprit in the pathogenesis of this myeloid neoplasm. This rare but significantly grave adverse effect should be kept in consideration when deciding on treatment options for gynecological malignancies.

  4. LncRNA NEAT1 contributes to paclitaxel resistance of ovarian cancer cells by regulating ZEB1 expression via miR-194

    Directory of Open Access Journals (Sweden)

    An J

    2017-11-01

    Full Text Available Jihong An,* Weiling Lv,* Yongzhou Zhang Department of Clinical Pharmacy, Huaihe Hospital of Henan University, Kaifeng, People’s Republic of China *These authors contributed equally to this work Background: Chemoresistance is one of the major obstacles for cancer therapy in the clinic. Nuclear paraspeckle assembly transcript 1 (NEAT1 has been reported as an oncogene in most malignancies such as lung cancer, esophageal cancer, and gastric cancer. This study is designed to investigate the function of NEAT1 in paclitaxel (PTX resistance of ovarian cancer and its potential molecular mechanism. Patients and methods: The expressions of NEAT1 and miR-194 in ovarian cancer tissues and cells were estimated by quantitative real-time polymerase chain reaction (qRT-PCR. MTT, flow cytometry, and Western blot assays were used to assess the effect of NEAT1 on PTX resistance in PTX-resistant ovarian cancer cells. Luciferase reporter assay was applied to examine the association between NEAT1, zinc finger E-box-binding homeobox 1 (ZEB1 and miR-194. Xenograft tumor model was established to confirm the biological role of NEAT1 in PTX resistance of ovarian cancer in vivo. Results: NEAT1 was upregulated, and miR-194 was downregulated in PTX-resistant ovarian cancer tissues and cells. Functionally, NEAT1 knockdown enhanced cell sensitivity to PTX via promoting PTX-induced apoptosis in vitro. NEAT1 was identified as a molecular sponge of miR-194 to upregulate ZEB1 expression. Mechanistically, NEAT1-knockdown-induced PTX sensitivity was mediated by miR-194/ZEB1 axis. Moreover, NEAT1 knockdown improved PTX sensitivity of ovarian cancer in vivo. Conclusion: NEAT1 contributed to PTX resistance of ovarian cancer cells at least partly through upregulating ZEB1 expression by sponging miR-194, elucidating a novel regulatory pathway of chemoresistance in PTX-resistant ovarian cancer cells and providing a possible long noncoding RNA (lncRNA-targeted therapy for ovarian cancer

  5. Omega-3 fatty acids are protective against paclitaxel-induced peripheral neuropathy: A randomized double-blind placebo controlled trial

    Directory of Open Access Journals (Sweden)

    Ghoreishi Zohreh

    2012-08-01

    Full Text Available Abstract Background Axonal sensory peripheral neuropathy is the major dose-limiting side effect of paclitaxel.Omega-3 fatty acids have beneficial effects on neurological disorders from their effects on neurons cells and inhibition of the formation of proinflammatory cytokines involved in peripheral neuropathy. Methods This study was a randomized double blind placebo controlled trial to investigate the efficacy of omega-3 fatty acids in reducing incidence and severity of paclitaxel-induced peripheral neuropathy (PIPN. Eligible patients with breast cancer randomly assigned to take omega-3 fatty acid pearls, 640 mg t.i.d during chemotherapy with paclitaxel and one month after the end of the treatment or placebo. Clinical and electrophysiological studies were performed before the onset of chemotherapy and one month after cessation of therapy to evaluate PIPN based on "reduced Total Neuropathy Score". Results Twenty one patients (70% of the group taking omega-3 fatty acid supplement (n = 30 did not develop PN while it was 40.7%( 11 patients in the placebo group(n = 27. A significant difference was seen in PN incidence (OR = 0.3, .95% CI = (0.10-0.88, p = 0.029. There was a non-significant trend for differences of PIPN severity between the two study groups but the frequencies of PN in all scoring categories were higher in the placebo group (0.95% CI = (−2.06 -0.02, p = 0.054. Conclusions Omega-3 fatty acids may be an efficient neuroprotective agent for prophylaxis against PIPN. Patients with breast cancer have a longer disease free survival rate with the aid of therapeutical agents. Finding a way to solve the disabling effects of PIPN would significantly improve the patients’ quality of life. Trial registration This trial was registered at ClinicalTrials.gov (NCT01049295

  6. Induced resistance: an enhancement of basal resistance?

    NARCIS (Netherlands)

    Vos, M. de; Robben, C.; Pelt, J.A. van; Loon, L.C. van; Pieterse, C.M.J.

    2002-01-01

    Upon primary pathogen attack, plants activate resistance mechanisms at the site of infection. Besides this so-called basal resistance, plants have also the ability to enhance their defensive capacity against future pathogen attack. There are at least two types of biologically induced resistance.

  7. Suppressive Effects of Bee Venom Acupuncture on Paclitaxel-Induced Neuropathic Pain in Rats: Mediation by Spinal α₂-Adrenergic Receptor.

    Science.gov (United States)

    Choi, Jiho; Jeon, Changhoon; Lee, Ji Hwan; Jang, Jo Ung; Quan, Fu Shi; Lee, Kyungjin; Kim, Woojin; Kim, Sun Kwang

    2017-10-31

    Paclitaxel, a chemotherapy drug for solid tumors, induces peripheral painful neuropathy. Bee venom acupuncture (BVA) has been reported to have potent analgesic effects, which are known to be mediated by activation of spinal α-adrenergic receptor. Here, we investigated the effect of BVA on mechanical hyperalgesia and spinal neuronal hyperexcitation induced by paclitaxel. The role of spinal α-adrenergic receptor subtypes in the analgesic effect of BVA was also observed. Administration of paclitaxel (total 8 mg/kg, intraperitoneal) on four alternate days (days 0, 2, 4, and 6) induced significant mechanical hyperalgesic signs, measured using a von Frey filament. BVA (1 mg/kg, ST36) relieved this mechanical hyperalgesia for at least two hours, and suppressed the hyperexcitation in spinal wide dynamic range neurons evoked by press or pinch stimulation. Both melittin (0.5 mg/kg, ST36) and phospholipase A2 (0.12 mg/kg, ST36) were shown to play an important part in this analgesic effect of the BVA, as they significantly attenuated the pain. Intrathecal pretreatment with the α₂-adrenergic receptor antagonist (idazoxan, 50 µg), but not α₁-adrenergic receptor antagonist (prazosin, 30 µg), blocked the analgesic effect of BVA. These results suggest that BVA has potent suppressive effects against paclitaxel-induced neuropathic pain, which were mediated by spinal α₂-adrenergic receptor.

  8. Suppressive Effects of Bee Venom Acupuncture on Paclitaxel-Induced Neuropathic Pain in Rats: Mediation by Spinal α2-Adrenergic Receptor

    Directory of Open Access Journals (Sweden)

    Jiho Choi

    2017-10-01

    Full Text Available Paclitaxel, a chemotherapy drug for solid tumors, induces peripheral painful neuropathy. Bee venom acupuncture (BVA has been reported to have potent analgesic effects, which are known to be mediated by activation of spinal α-adrenergic receptor. Here, we investigated the effect of BVA on mechanical hyperalgesia and spinal neuronal hyperexcitation induced by paclitaxel. The role of spinal α-adrenergic receptor subtypes in the analgesic effect of BVA was also observed. Administration of paclitaxel (total 8 mg/kg, intraperitoneal on four alternate days (days 0, 2, 4, and 6 induced significant mechanical hyperalgesic signs, measured using a von Frey filament. BVA (1 mg/kg, ST36 relieved this mechanical hyperalgesia for at least two hours, and suppressed the hyperexcitation in spinal wide dynamic range neurons evoked by press or pinch stimulation. Both melittin (0.5 mg/kg, ST36 and phospholipase A2 (0.12 mg/kg, ST36 were shown to play an important part in this analgesic effect of the BVA, as they significantly attenuated the pain. Intrathecal pretreatment with the α2-adrenergic receptor antagonist (idazoxan, 50 µg, but not α1-adrenergic receptor antagonist (prazosin, 30 µg, blocked the analgesic effect of BVA. These results suggest that BVA has potent suppressive effects against paclitaxel-induced neuropathic pain, which were mediated by spinal α2-adrenergic receptor.

  9. Preventative and therapeutic effects of a GABA transporter 1 inhibitor administered systemically in a mouse model of paclitaxel-induced neuropathic pain

    Directory of Open Access Journals (Sweden)

    Willias Masocha

    2016-12-01

    Full Text Available Background There is a dearth of drugs to manage a dose-limiting painful peripheral neuropathy induced by paclitaxel in some patients during the treatment of cancer. Gamma-aminobutyric acid transporter-1 (GAT-1 whose expression is increased in the brain and spinal cord during paclitaxel-induced neuropathic pain (PINP might be a potential therapeutic target for managing PINP. Thus, our aim was to evaluate if systemic administration of a GAT-1 inhibitor ameliorates PINP. Methods The reaction latency to thermal stimuli (hot plate test; at 55 °C and cold stimuli (cold plate test; at 4 °C of female BALB/c mice was recorded before and after intraperitoneal treatment with paclitaxel, its vehicle, and/or a selective GAT-1 inhibitor NO-711. The effects of NO-711 on motor coordination were evaluated using the rotarod test at a constant speed of 4 rpm or accelerating mode from 4 rpm to 40 rpm over 5 min. Results The coadministration of paclitaxel with NO-711 3 mg/kg prevented the development of paclitaxel-induced thermal hyperalgesia and cold allodynia at day 7 after drug treatment. NO-711 at 3 mg/kg produced antihyperalgesic activity up to 1 h and antiallodynic activity up to 2 h in mice with established paclitaxel-induced thermal hyperalgesia and cold allodynia. No motor deficits were observed with NO-711 at a dose of 3 mg/kg, whereas a higher dose 5 mg/kg caused motor impairment and reduced mean time spent on the rotarod at a constant speed of 4 rpm. However, at a rotarod accelerating mode from 4 rpm to 40 rpm over 5 min, NO-711 3 mg/kg caused motor impairment up to 1 h, but had recovered by 2 h. Conclusions These results show that systemic administration of the GAT-1 inhibitor NO-711 has preventative and therapeutic activity against paclitaxel-induced thermal hyperalgesia and cold allodynia. NO-711’s antiallodynic effects, but not antihyperalgesic effects, were independent of its motor impairment/sedation properties. Thus, low doses of GAT-1

  10. Differentially expressed proteins in human MCF-7 breast cancer cells sensitive and resistant to paclitaxel

    Czech Academy of Sciences Publication Activity Database

    Pavlíková, N.; Bartoňová, I.; Balušíková, K.; Kopperová, D.; Halada, Petr; Kovář, J.

    2015-01-01

    Roč. 333, č. 1 (2015), s. 1-10 ISSN 0014-4827 Institutional support: RVO:61388971 Keywords : Breast cancer * Taxane resistance * 2-D electrophoresis Subject RIV: CE - Biochemistry Impact factor: 3.378, year: 2015

  11. Polyethylenimine-functionalized silver nanoparticle-based co-delivery of paclitaxel to induce HepG2 cell apoptosis

    Directory of Open Access Journals (Sweden)

    Li Y

    2016-12-01

    Full Text Available Yinghua Li,1,* Min Guo,1,* Zhengfang Lin,1 Mingqi Zhao,1 Misi Xiao,1 Changbing Wang,1 Tiantian Xu,1 Tianfeng Chen,2 Bing Zhu1 1Center Laboratory, Guangzhou Women and Children’s Medical Center, Guangzhou Medical University, 2Department of Chemistry, Jinan University, Guangzhou, People’s Republic of China *These authors contributed equally to this work Abstract: Hepatocarcinoma is the third leading cause of cancer-related deaths around the world. Recently, a novel emerging nanosystem as anticancer therapeutic agents with intrinsic therapeutic properties has been widely used in various medical applications. In this study, surface decoration of functionalized silver nanoparticles (AgNPs by polyethylenimine (PEI and paclitaxel (PTX was synthesized. The purpose of this study was to evaluate the effect of Ag@PEI@PTX on cytotoxic and anticancer mechanism on HepG2 cells. The transmission electron microscope image and 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide assay showed that Ag@PEI@PTX had satisfactory size distribution and high stability and selectivity between cancer and normal cells. Ag@PEI@PTX-induced HepG2 cell apoptosis was confirmed by accumulation of the sub-G1 cells population, translocation of phosphatidylserine, depletion of mitochondrial membrane potential, DNA fragmentation, caspase-3 activation, and poly(ADP-ribose polymerase cleavage. Furthermore, Ag@PEI@PTX enhanced cytotoxic effects on HepG2 cells and triggered intracellular reactive oxygen species; the signaling pathways of AKT, p53, and MAPK were activated to advance cell apoptosis. In conclusion, the results reveal that Ag@PEI@PTX may provide useful information on Ag@PEI@PTX-induced HepG2 cell apoptosis and as appropriate candidate for chemotherapy of cancer. Keywords: silver nanoparticles, polyethylenimine, paclitaxel, reactive oxygen species, apoptosis

  12. Paclitaxel-resistant HeLa cells have up-regulated levels of reactive oxygen species and increased expression of taxol resistance gene 1.

    Science.gov (United States)

    Bi, Wenxiang; Wang, Yuxia; Sun, Gaoying; Zhang, Xiaojin; Wei, Yongqing; Li, Lu; Wang, Xiaoyuan

    2014-07-01

    This study is to establish a paclitaxel (PTX)-resistant human cervical carcinoma HeLa cell line (HeLa/PTX) and to investigate its redox characteristics and the expression of taxol resistance gene 1 (Txr1). HeLa cells were treated with PTX and effects of PTX on cell proliferation were detected through cell counting and the MTT assay. Levels of cellular reactive oxygen species (ROS), reduced glutathione (GSH), and oxidized glutathione (GSSG) as well as the ratio of GSH to GSSG were measured by the 2,7-difluorescein diacetate (DCFH-DA) method and the 5,5'dithiobis(2-nitrobenzoic acid) (DTNB) method. Activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were determined by the nitrite formation method, the molybdate colorimetric method, and the DTNB colorimetric method, respectively. The level of Txr1 mRNA was determined by real-time PCR. Compared with the regular HeLa cells, HeLa/PTX cells were larger in size and had more cytoplasmic granules. The population doubling time for HeLa/PTX cells was 1.32 times of that of HeLa cells (PHeLa/PTX cells showed stronger resistance to PTX than HeLa cells with a resistance index of 122.69. HeLa/PTX cells had higher levels of ROS (PHeLa cells. HeLa/PTX cells, with higher levels of ROS and Txr1 mRNA expression, are more resistant to PTX than HeLa cells.

  13. Gene expression profile of sodium channel subunits in the anterior cingulate cortex during experimental paclitaxel-induced neuropathic pain in mice

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    Willias Masocha

    2016-11-01

    Full Text Available Paclitaxel, a chemotherapeutic agent, causes neuropathic pain whose supraspinal pathophysiology is not fully understood. Dysregulation of sodium channel expression, studied mainly in the periphery and spinal cord level, contributes to the pathogenesis of neuropathic pain. We examined gene expression of sodium channel (Nav subunits by real time polymerase chain reaction (PCR in the anterior cingulate cortex (ACC at day 7 post first administration of paclitaxel, when mice had developed paclitaxel-induced thermal hyperalgesia. The ACC was chosen because increased activity in the ACC has been observed during neuropathic pain. In the ACC of vehicle-treated animals the threshold cycle (Ct values for Nav1.4, Nav1.5, Nav1.7, Nav1.8 and Nav1.9 were above 30 and/or not detectable in some samples. Thus, comparison in mRNA expression between untreated control, vehicle-treated and paclitaxel treated animals was done for Nav1.1, Nav1.2, Nav1.3, Nav1.6, Nax as well as Navβ1–Navβ4. There were no differences in the transcript levels of Nav1.1–Nav1.3, Nav1.6, Nax, Navβ1–Navβ3 between untreated and vehicle-treated mice, however, vehicle treatment increased Navβ4 expression. Paclitaxel treatment significantly increased the mRNA expression of Nav1.1, Nav1.2, Nav1.6 and Nax, but not Nav1.3, sodium channel alpha subunits compared to vehicle-treated animals. Treatment with paclitaxel significantly increased the expression of Navβ1 and Navβ3, but not Navβ2 and Navβ4, sodium channel beta subunits compared to vehicle-treated animals. These findings suggest that during paclitaxel-induced neuropathic pain (PINP there is differential upregulation of sodium channels in the ACC, which might contribute to the increased neuronal activity observed in the area during neuropathic pain.

  14. Re-irradiation associated to cetuximab and paclitaxel in the recurrences in irradiated field of upper aero-digestive ducts tumors resistant to platina salts; Re-irradiation associee au cetuximab et au paclitaxel dans les recidives en territoire irradie des tumeurs des voies aero-digestives superieures resistantes aux sels de platine

    Energy Technology Data Exchange (ETDEWEB)

    Martin, L.M. [Centre Guillaume-Le-Conquerant, 76 - Le Havre (France); Moran, A.R.; Pavlovitch, J.M. [Clinique du Petit-Colmoulin, 76 - Harfleur (France); El Amarti, R. [Hopital Monod, 76 - Montivilliers (France); Damour, M. [CMC Ormeaux-Vauban, 76 - Le Havre (France)

    2007-11-15

    The objective of this study is to present the preliminary results of the toxicity and efficiency evaluation of the association 're-irradiation-cetuximab-paclitaxel' in the recurrences of upper aero-digestive ducts tumors in irradiated field resistant to platinum salts. (N.C.)

  15. Biodegradable mixed MPEG-SS-2SA/TPGS micelles for triggered intracellular release of paclitaxel and reversing multidrug resistance

    Directory of Open Access Journals (Sweden)

    Dong K

    2016-10-01

    Full Text Available Kai Dong,1 Yan Yan,2 Pengchong Wang,2 Xianpeng Shi,2 Lu Zhang,2 Ke Wang,2 Jianfeng Xing,2 Yalin Dong1 1Department of Pharmacy, The First Affiliated Hospital of Xi’an Jiaotong University, 2School of Pharmacy, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China Abstract: In this study, a type of multifunctional mixed micelles were prepared by a novel biodegradable amphiphilic polymer (MPEG-SS-2SA and a multidrug resistance (MDR reversal agent (D-α-tocopheryl polyethylene glycol succinate, TPGS. The mixed micelles could achieve rapid intracellular drug release and reversal of MDR. First, the amphiphilic polymer, MPEG-SS-2SA, was synthesized through disulfide bonds between poly (ethylene glycol monomethyl ether (MPEG and stearic acid (SA. The structure of the obtained polymer was similar to poly (ethylene glycol-phosphatidylethanolamine (PEG-PE. Then the mixed micelles, MPEG-SS-2SA/TPGS, were prepared by MPEG-SS-2SA and TPGS through the thin film hydration method and loaded paclitaxel (PTX as the model drug. The in vitro release study revealed that the mixed micelles could rapidly release PTX within 24 h under a reductive environment because of the breaking of disulfide bonds. In cell experiments, the mixed micelles significantly inhibited the activity of mitochondrial respiratory complex II, also reduced the mitochondrial membrane potential, and the content of adenosine triphosphate, thus effectively inhibiting the efflux of PTX from cells. Moreover, in the confocal laser scanning microscopy, cellular uptake and 3-(4,5-dimethyl-thiazol-2-yl-2,5-diphenyl-tetrazolium bromide assays, the MPEG-SS-2SA/TPGS micelles achieved faster release and more uptake of PTX in Michigan Cancer Foundation-7/PTX cells and showed better antitumor effects as compared with the insensitive control. In conclusion, the biodegradable mixed micelles, MPEG-SS-2SA/TPGS, could be potential vehicles for delivering hydrophobic chemotherapeutic drugs in

  16. A3 adenosine receptor agonist prevents the development of paclitaxel-induced neuropathic pain by modulating spinal glial-restricted redox-dependent signaling pathways.

    Science.gov (United States)

    Janes, Kali; Esposito, Emanuela; Doyle, Timothy; Cuzzocrea, Salvatore; Tosh, Dillip K; Jacobson, Kenneth A; Salvemini, Daniela

    2014-12-01

    Chemotherapy-induced peripheral neuropathy accompanied by chronic neuropathic pain is the major dose-limiting toxicity of several anticancer agents including the taxane paclitaxel (Taxol). A critical mechanism underlying paclitaxel-induced neuropathic pain is the increased production of peroxynitrite in spinal cord generated in response to activation of the superoxide-generating enzyme, NADPH oxidase. Peroxynitrite in turn contributes to the development of neuropathic pain by modulating several redox-dependent events in spinal cord. We recently reported that activation of the Gi/Gq-coupled A3 adenosine receptor (A3AR) with selective A3AR agonists (ie, IB-MECA) blocked the development of chemotherapy induced-neuropathic pain evoked by distinct agents, including paclitaxel, without interfering with anticancer effects. The mechanism or mechanisms of action underlying these beneficial effects has yet to be explored. We now demonstrate that IB-MECA attenuates the development of paclitaxel-induced neuropathic pain by inhibiting the activation of spinal NADPH oxidase and two downstream redox-dependent systems. The first relies on inhibition of the redox-sensitive transcription factor (NFκB) and mitogen activated protein kinases (ERK and p38) resulting in decreased production of neuroexcitatory/proinflammatory cytokines (TNF-α, IL-1β) and increased formation of the neuroprotective/anti-inflammatory IL-10. The second involves inhibition of redox-mediated posttranslational tyrosine nitration and modification (inactivation) of glia-restricted proteins known to play key roles in regulating synaptic glutamate homeostasis: the glutamate transporter GLT-1 and glutamine synthetase. Our results unravel a mechanistic link into biomolecular signaling pathways employed by A3AR activation in neuropathic pain while providing the foundation to consider use of A3AR agonists as therapeutic agents in patients with chemotherapy-induced peripheral neuropathy. Copyright © 2014

  17. Comparative vascular responses three months after paclitaxel and everolimus-eluting stent implantation in streptozotocin-induced diabetic porcine coronary arteries

    Directory of Open Access Journals (Sweden)

    Sheehy Alexander

    2012-06-01

    Full Text Available Abstract Background Diabetes remains a significant risk factor for restenosis/thrombosis following stenting. Although vascular healing responses following drug-eluting stent (DES treatment have been characterized previously in healthy animals, comparative assessments of different DES in a large animal model with isolated features of diabetes remains limited. We aimed to comparatively assess the vascular response to paclitaxel-eluting (PES and everolimus-eluting (EES stents in a porcine coronary model of streptozotocin (STZ-induced type I diabetes. Method Twelve Yucatan swine were induced hyperglycemic with a single STZ dose intravenously to ablate pancreatic β-cells. After two months, each animal received one XIENCE V® (EES and one Taxus Liberte (PES stent, respectively, in each coronary artery. After three months, vascular healing was assessed by angiography and histomorphometry. Comparative in vitro effects of everolimus and paclitaxel (10-5 M–10-12 M after 24 hours on carotid endothelial (EC and smooth muscle (SMC cell viability under hyperglycemic (42 mM conditions were assayed by ELISA. Caspase-3 fluorescent assay was used to quantify caspase-3 activity of EC treated with everolimus or paclitaxel (10-5 M, 10-7 M for 24 hours. Results After 3 months, EES reduced neointimal area (1.60 ± 0.41 mm, p vs. 0.08 ± 0.05, greater medial necrosis grade (0.52 ± 0.26 vs. 0.0 ± 0.0, and persistently elevated fibrin scores (1.60 ± 0.60 vs. 0.63 ± 0.41 with PES compared to EES (p In vitro, paclitaxel significantly increased (p -7 M, while everolimus did not affect EC/SMC apoptosis/necrosis within the dose range tested. In ECs, paclitaxel (10-5 M significantly increased caspase-3 activity (p  Conclusion After 3 months, both DES exhibited signs of delayed healing in a STZ-induced diabetic swine model. PES exhibited greater neointimal area, increased inflammation, greater medial necrosis, and

  18. Down-regulated βIII-tubulin Expression Can Reverse Paclitaxel Resistance in A549/Taxol Cells Lines

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    Yinling ZHUO

    2014-08-01

    Full Text Available Background and objective Chemotherapy drug resistance is the primary causes of death in patients with pulmonary carcinoma which make tumor recurrence or metastasis. β-tubulin is the main cell targets of anti-microtubule drug. Increased expression of βIII-tubulin has been implicated in non-small cell lung cancer (NSCLC cell lines. To explore the relationship among the expression level of βIII-tubulin and the sensitivity of A549/Taxolcell lines to Taxol and cell cycles and cell apoptosis by RNA interference-mediated inhibition of βIII-tubulin in A549/Taxol cells. Methods Three pairs of siRNA targetd βIII-tubulin were designed and prepared, which were transfected into A549/Taxol cells using LipofectamineTM 2000. We detected the expression of βIII-tubulin mRNA using Real-time fluorescence qRT-PCR. Tedhen we selected the most efficient siRNA by the expression of βIII-tubulin mRNA in transfected group. βIII-tubulin protein level were mesured by Western blot. The taxol sensitivity in transfected group were evaluated by MTT assay. And the cell apoptosis and cell cycles were determined by flow cytometry. Results βIII-tubulin mRNA levels in A549/Taxol cells were significantly decreased in transfected grop by Real-time qRT-PCR than control groups. And βIII-tubulin siRNA-1 sequence showed the highest transfection efficiency, which was (87.73±4.87% (P<0.01; Western blot results showed that the expressional level of BIII tublin protein was significantly down-reulated in the transfectant cells than thant in the control cells. By MTT assay, we showed that the inhibition ratio of Taxol to A549/Taxol cells transfeced was higher than that of control group (51.77±4.60% (P<0.01. The early apoptosis rate of A549/Taxol cells in transfected group were significantly higher than that of control group (P<0.01; G2-M content in taxol group obviously increased than untreated samples by the cell cycle (P<0.05. Conclusion βIII-tubulin down-regulated significantly

  19. Paclitaxel and the dietary flavonoid fisetin: a synergistic combination that induces mitotic catastrophe and autophagic cell death in A549 non-small cell lung cancer cells.

    Science.gov (United States)

    Klimaszewska-Wisniewska, Anna; Halas-Wisniewska, Marta; Tadrowski, Tadeusz; Gagat, Maciej; Grzanka, Dariusz; Grzanka, Alina

    2016-01-01

    The use of the dietary polyphenols as chemosensitizing agents to enhance the efficacy of conventional cytostatic drugs has recently gained the attention of scientists and clinicians as a plausible approach for overcoming the limitations of chemotherapy (e.g. drug resistance and cytotoxicity). The aim of this study was to investigate whether a naturally occurring diet-based flavonoid, fisetin, at physiologically attainable concentrations, could act synergistically with clinically achievable doses of paclitaxel to produce growth inhibitory and/or pro-death effects on A549 non-small cell lung cancer cells, and if it does, what mechanisms might be involved. The drug-drug interactions were analyzed based on the combination index method of Chou and Talalay and the data from MTT assays. To provide some insights into the mechanism underlying the synergistic action of fisetin and paclitaxel, selected morphological, biochemical and molecular parameters were examined, including the morphology of cell nuclei and mitotic spindles, the pattern of LC3-II immunostaining, the formation of autophagic vacuoles at the electron and fluorescence microscopic level, the disruption of cell membrane asymmetry/integrity, cell cycle progression and the expression level of LC3-II, Bax, Bcl-2 and caspase-3 mRNA. Here, we reported the first experimental evidence for the existence of synergism between fisetin and paclitaxel in the in vitro model of non-small cell lung cancer. This synergism was, at least partially, ascribed to the induction of mitotic catastrophe. The switch from the cytoprotective autophagy to the autophagic cell death was also implicated in the mechanism of the synergistic action of fisetin and paclitaxel in the A549 cells. In addition, we revealed that the synergism between fisetin and paclitaxel was cell line-specific as well as that fisetin synergizes with arsenic trioxide, but not with mitoxantrone and methotrexate in the A549 cells. Our results provide rationale for

  20. Systemic resistance induced by rhizosphere bacteria

    NARCIS (Netherlands)

    Loon, L.C. van; Bakker, P.A.H.M.; Pieterse, C.M.J.

    1998-01-01

    Nonpathogenic rhizobacteria can induce a systemic resistance in plants that is phenotypically similar to pathogen-induced systemic acquired resistance (SAR). Rhizobacteria-mediated induced systemic resistance (ISR) has been demonstrated against fungi, bacteria, and viruses in Arabidopsis, bean,

  1. Dual PI3K/mTOR inhibitor BEZ235 as a promising therapeutic strategy against paclitaxel-resistant gastric cancer via targeting PI3K/Akt/mTOR pathway.

    Science.gov (United States)

    Chen, Dongshao; Lin, Xiaoting; Zhang, Cheng; Liu, Zhentao; Chen, Zuhua; Li, Zhongwu; Wang, Jingyuan; Li, Beifang; Hu, Yanting; Dong, Bin; Shen, Lin; Ji, Jiafu; Gao, Jing; Zhang, Xiaotian

    2018-01-26

    Paclitaxel (PTX) is widely used in the front-line chemotherapy for gastric cancer (GC), but resistance limits its use. Due to the lack of proper models, mechanisms underlying PTX resistance in GC were not well studied. Using established PTX-resistant GC cell sublines HGC-27R, we for the first time integrated biological traits and molecular mechanisms of PTX resistance in GC. Data revealed that PTX-resistant GC cells were characterized by microtubular disorders, an EMT phenotype, reduced responses to antimitotic drugs, and resistance to apoptosis (marked by upregulated β-tubulin III, vimentin, attenuated changes in G 2 /M molecules or pro-apoptotic factors in response to antimitotic drugs or apoptotic inducers, respectively). Activation of the phosphoinositide 3-kinase, the serine/threonine kinase Akt and mammalian target of rapamycin (PI3K/Akt/mTOR) and mitogen-activated protein kinase (MAPK) pathways were also observed, which might be the reason for above phenotypic alternations. In vitro data suggested that targeting these pathways were sufficient to elicit antitumor responses in PTX-resistant GC, in which the dual PI3K/mTOR inhibitor BEZ235 displayed higher therapeutic efficiency than the mTOR inhibitor everolimus or the MEK inhibitor AZD6244. Antitumor effects of BEZ235 were also confirmed in mice bearing HGC-27R tumors. Thus, these data suggest that PI3K/Akt/mTOR and MAPK pathway inhibition, especially PI3K/mTOR dual blockade, might be a promising therapeutic strategy against PTX-resistant GC.

  2. DRG Voltage-Gated Sodium Channel 1.7 Is Upregulated in Paclitaxel-Induced Neuropathy in Rats and in Humans with Neuropathic Pain.

    Science.gov (United States)

    Li, Yan; North, Robert Y; Rhines, Laurence D; Tatsui, Claudio Esteves; Rao, Ganesh; Edwards, Denaya D; Cassidy, Ryan M; Harrison, Daniel S; Johansson, Caj A; Zhang, Hongmei; Dougherty, Patrick M

    2018-01-31

    Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse effect experienced by cancer patients receiving treatment with paclitaxel. The voltage-gated sodium channel 1.7 (Na v 1.7) plays an important role in multiple preclinical models of neuropathic pain and in inherited human pain phenotypes, and its gene expression is increased in dorsal root ganglia (DRGs) of paclitaxel-treated rats. Hence, the potential of change in the expression and function of Na v 1.7 protein in DRGs from male rats with paclitaxel-related CIPN and from male and female humans with cancer-related neuropathic pain was tested here. Double immunofluorescence in CIPN rats showed that Na v 1.7 was upregulated in small DRG neuron somata, especially those also expressing calcitonin gene-related peptide (CGRP), and in central processes of these cells in the superficial spinal dorsal horn. Whole-cell patch-clamp recordings in rat DRG neurons revealed that paclitaxel induced an enhancement of ProTx II (a selective Na v 1.7 channel blocker)-sensitive sodium currents. Bath-applied ProTx II suppressed spontaneous action potentials in DRG neurons occurring in rats with CIPN, while intrathecal injection of ProTx II significantly attenuated behavioral signs of CIPN. Complementarily, DRG neurons isolated from segments where patients had a history of neuropathic pain also showed electrophysiological and immunofluorescence results indicating an increased expression of Na v 1.7 associated with spontaneous activity. Na v 1.7 was also colocalized in human cells expressing transient receptor potential vanilloid 1 and CGRP. Furthermore, ProTx II decreased firing frequency in human DRGs with spontaneous action potentials. This study suggests that Na v 1.7 may provide a potential new target for the treatment of neuropathic pain, including chemotherapy (paclitaxel)-induced neuropathic pain. SIGNIFICANCE STATEMENT This work demonstrates that the expression and function of the voltage-gated sodium channel Na

  3. Quantitative image analysis of intra-tumoral bFGF level as a molecular marker of paclitaxel resistance

    Directory of Open Access Journals (Sweden)

    Wientjes M Guillaume

    2008-01-01

    Full Text Available Abstract Background The role of basic fibroblast growth factor (bFGF in chemoresistance is controversial; some studies showed a relationship between higher bFGF level and chemoresistance while other studies showed the opposite finding. The goal of the present study was to quantify bFGF levels in archived tumor tissues, and to determine its relationship with chemosensitivity. Methods We established an image analysis-based method to quantify and convert the immunostaining intensity of intra-tumor bFGF to concentrations; this was accomplished by generating standard curves using human xenograft tumors as the renewable tissue source for simultaneous image analysis and ELISA. The relationships between bFGF concentrations and tumor chemosensitivity of patient tumors (n = 87 to paclitaxel were evaluated using linear regression analysis. Results The image analysis results were compared to our previous results obtained using a conventional, semi-quantitative visual scoring method. While both analyses indicated an inverse relationship between bFGF level and tumor sensitivity to paclitaxel, the image analysis method, by providing bFGF levels in individual tumors and therefore more data points (87 numerical values as opposed to four groups of staining intensities, further enabled the quantitative analysis of the relationship in subgroups of tumors with different pathobiological properties. The results show significant correlation between bFGF level and tumor sensitivity to the antiproliferation effect, but not the apoptotic effect, of paclitaxel. We further found stronger correlations of bFGF level and paclitaxel sensitivity in four tumor subgroups (high stage, positive p53 staining, negative aFGF staining, containing higher-than-median bFGF level, compared to all other groups. These findings suggest that the relationship between intra-tumoral bFGF level and paclitaxel sensitivity was context-dependent, which may explain the previous contradictory findings

  4. A proof-of-concept trial of protein kinase C iota inhibition with auranofin for the paclitaxel-induced acute pain syndrome.

    Science.gov (United States)

    Jatoi, Aminah; Grudem, Megan E; Dockter, Travis J; Block, Matthew S; Villasboas, Jose C; Tan, Angelina; Deering, Erin; Kasi, Pashtoon M; Mansfield, Aaron S; Botero, Juliana Perez; Okuno, Scott H; Smith, Deanne R; Fields, Alan P

    2017-03-01

    Paclitaxel causes the paclitaxel-induced acute pain (PIAP) syndrome. Based on preclinical data, we hypothesized that the protein kinase C (PKC) iota inhibitor, auranofin (a gold salt used for other pain conditions), palliates this pain. In a randomized, double-blinded manner, patients who had suffered this syndrome were assigned a one-time dose of auranofin 6 mg orally on day #2 of the chemotherapy cycle (post-paclitaxel) versus placebo. Patients completed the Brief Pain Inventory and a pain diary on days 2 through 8 and at the end of the cycle. The primary endpoint was pain scores, as calculated by area under the curve, in response to "Please rate your pain by circling the one number that best describes your pain at its worse in the last 24 hours." Thirty patients were enrolled. For the primary endpoint, mean area under the curve of 55 units (standard deviation 19) and 61 units (standard deviation 22) were observed in auranofin-treated and placebo-exposed patients, respectively (p = 0.44). On day 8 and at the end of the cycle, pain scores in auranofin-treated patients were more favorable, although differences were not statistically significant. In the dose schedule studied, auranofin did not palliate the PIAP syndrome, but delayed beneficial trends suggest further study for this indication.

  5. The maintenance of cisplatin- and paclitaxel-induced mechanical and cold allodynia is suppressed by cannabinoid CB2 receptor activation and independent of CXCR4 signaling in models of chemotherapy-induced peripheral neuropathy

    Directory of Open Access Journals (Sweden)

    Deng Liting

    2012-09-01

    Full Text Available Abstract Background Chemotherapeutic agents produce dose-limiting peripheral neuropathy through mechanisms that remain poorly understood. We previously showed that AM1710, a cannabilactone CB2 agonist, produces antinociception without producing central nervous system (CNS-associated side effects. The present study was conducted to examine the antinociceptive effect of AM1710 in rodent models of neuropathic pain evoked by diverse chemotherapeutic agents (cisplatin and paclitaxel. A secondary objective was to investigate the potential contribution of alpha-chemokine receptor (CXCR4 signaling to both chemotherapy-induced neuropathy and CB2 agonist efficacy. Results AM1710 (0.1, 1 or 5 mg/kg i.p. suppressed the maintenance of mechanical and cold allodynia in the cisplatin and paclitaxel models. Anti-allodynic effects of AM1710 were blocked by the CB2 antagonist AM630 (3 mg/kg i.p., but not the CB1 antagonist AM251 (3 mg/kg i.p., consistent with a CB2-mediated effect. By contrast, blockade of CXCR4 signaling with its receptor antagonist AMD3100 (10 mg/kg i.p. failed to attenuate mechanical or cold hypersensitivity induced by either cisplatin or paclitaxel. Moreover, blockade of CXCR4 signaling failed to alter the anti-allodynic effects of AM1710 in the paclitaxel model, further suggesting distinct mechanisms of action. Conclusions Our results indicate that activation of cannabinoid CB2 receptors by AM1710 suppresses both mechanical and cold allodynia in two distinct models of chemotherapy-induced neuropathic pain. By contrast, CXCR4 signaling does not contribute to the maintenance of chemotherapy-induced established neuropathy or efficacy of AM1710. Our studies suggest that CB2 receptors represent a promising therapeutic target for the treatment of toxic neuropathies produced by cisplatin and paclitaxel chemotherapeutic agents.

  6. Evaluation of In-111 DTPA-paclitaxel scintigraphy to predict response on murine tumors to paclitaxel

    International Nuclear Information System (INIS)

    Inoue, Tomio; Li, C.; Yang, D.J.

    1999-01-01

    Our goal was to determine whether scintigraphy with 111 In-DTPA-paclitaxel could predict the response to chemotherapy with paclitaxel. Ovarian carcinoma (OCA 1), mammary carcinoma (MCA-4), fibrosarcoma (FSA) and squamous cell carcinoma (SCC VII) were inoculated into the thighs of female C3Hf/Kam mice. Mice bearing 8 mm tumors were treated with paclitaxel (40 mg/kg). The growth delay, which was defined as the time in days for tumors in the treated groups to grow from 8 to 12 mm in diameter minus the time in days for tumors in the untreated control group to reach the same size, was measured to determine the effect of paclitaxel on the tumors. Sequential scintigraphy in mice bearing 10 to 14 mm tumors was conducted at 5, 30, 60, 120, 240 min and 24 hrs postinjection of 111 In-DTPA-paclitaxel (3.7 MBq) or 111 In-DTPA as a control tracer. The tumor uptakes (% injection dose/pixel) were determined. The growth delay of OCA 1, MCA-4, FSA and SCC VII tumors was 13.6, 4.0, -0.02 and -0.28 days, respectively. In other words, OCA 1 and MCA-4 were paclitaxel-sensitive tumors, whereas FSA and SCC VII were paclitaxel-resistant tumors. The tumor uptakes at 24 hrs postinjection of In-111 DTPA paclitaxel of OCA 1, MCA-4, FSA and SCC VII were 1.0 x 10 -3 , 1.6 x 10 -3 , 2.2 x 10 -3 and 9.0 x 10 -3 % injection dose/pixel, respectively. There was no correlation between the response to chemotherapy with paclitaxel and the tumor uptakes of 111 In-DTPA-paclitaxel. Scintigraphy with 111 In-DTPA-paclitaxel could not predict the response to paclitaxel chemotherapy. Although there was significant accumulation of the paclitaxel in the tumor cells, additional mechanisms must be operative for the agent to be effective against the neoplasm. 111 In-DTPA-paclitaxel activity is apparently different from that of paclitaxel with Cremophor. (author)

  7. Codelivery for Paclitaxel and Bcl-2 Conversion Gene by PHB-PDMAEMA Amphiphilic Cationic Copolymer for Effective Drug Resistant Cancer Therapy.

    Science.gov (United States)

    Wang, Xiaoyuan; Liow, Sing Shy; Wu, Qiaoqiong; Li, Chuang; Owh, Cally; Li, Zibiao; Loh, Xian Jun; Wu, Yun-Long

    2017-11-01

    Antiapoptotic Bcl-2 protein's upregulated expression is a key reason for drug resistance leading to failure of chemotherapy. In this report, a series of biocompatible amphiphilic cationic poly[(R)-3-hydroxybutyrate] (PHB)-b-poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) copolymer, comprising hydrophobic PHB block and cationic PDMAEMA block, is designed to codeliver hydrophobic chemotherapeutic paclitaxel and Bcl-2 converting gene Nur77/ΔDBD with enhanced stability, due to the micelle formation by hydrophobic PHB segment. This copolymer shows less toxicity but similar gene transfection efficiency to polyethyenimine (25k). More importantly, this codelivery approach by PHB-PDMAEMA leads to increased drug resistant HepG2/Bcl-2 cancer cell death, by increased expression of Nur77 proteins in the Bcl-2 present intracellular mitochondria. This work signifies for the first time that cationic amphiphilic PHB-b-PDMAEMA copolymers can be utilized for the drug and gene codelivery to drug resistant cancer cells with high expression of antiapoptosis Bcl-2 protein and the positive results are encouraging for the further design of codelivery platforms for combating drug resistant cancer cells. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Ototoxicity of paclitaxel in rat cochlear organotypic cultures

    International Nuclear Information System (INIS)

    Dong, Yang; Ding, Dalian; Jiang, Haiyan; Shi, Jian-rong; Salvi, Richard; Roth, Jerome A.

    2014-01-01

    Paclitaxel (taxol) is a widely used antineoplastic drug employed alone or in combination to treat many forms of cancer. Paclitaxel blocks microtubule depolymerization thereby stabilizing microtubules and suppressing cell proliferation and other cellular processes. Previous reports indicate that paclitaxel can cause mild to moderate sensorineural hearing loss and some histopathologic changes in the mouse cochlea; however, damage to the neurons and the underlying cell death mechanisms are poorly understood. To evaluate the ototoxicity of paclitaxel in more detail, cochlear organotypic cultures from postnatal day 3 rats were treated with paclitaxel for 24 or 48 h with doses ranging from 1 to 30 μM. No obvious histopathologies were observed after 24 h treatment with any of the paclitaxel doses employed, but with 48 h treatment, paclitaxel damaged cochlear hair cells in a dose-dependent manner and also damaged auditory nerve fibers and spiral ganglion neurons (SGN) near the base of the cochlea. TUNEL labeling was negative in the organ of Corti, but positive in SGN with karyorrhexis 48 h after 30 μM paclitaxel treatment. In addition, caspase-6, caspase-8 and caspase-9 labeling was present in SGN treated with 30 μM paclitaxel for 48 h. These results suggest that caspase-dependent apoptotic pathways are involved in paclitaxel-induced damage of SGN, but not hair cells in cochlea. - Highlights: • Paclitaxel was toxic to cochlear hair cells and spiral ganglion neurons. • Paclitaxel-induced spiral ganglion degeneration was apoptotic. • Paclitaxel activated caspase-6, -8 and -8 in spiral ganglion neurons

  9. Ototoxicity of paclitaxel in rat cochlear organotypic cultures

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Yang [Shanghai University of Traditional Chinese Medicine, Shanghai 201203 (China); Center for Hearing and Deafness, University at Buffalo, NY 14214 (United States); Ding, Dalian; Jiang, Haiyan [Center for Hearing and Deafness, University at Buffalo, NY 14214 (United States); Shi, Jian-rong [Shanghai University of Traditional Chinese Medicine, Shanghai 201203 (China); Salvi, Richard [Center for Hearing and Deafness, University at Buffalo, NY 14214 (United States); Roth, Jerome A., E-mail: jaroth@buffalo.edu [Department of Pharmacology and Toxicology, University at Buffalo, NY 14214 (United States)

    2014-11-01

    Paclitaxel (taxol) is a widely used antineoplastic drug employed alone or in combination to treat many forms of cancer. Paclitaxel blocks microtubule depolymerization thereby stabilizing microtubules and suppressing cell proliferation and other cellular processes. Previous reports indicate that paclitaxel can cause mild to moderate sensorineural hearing loss and some histopathologic changes in the mouse cochlea; however, damage to the neurons and the underlying cell death mechanisms are poorly understood. To evaluate the ototoxicity of paclitaxel in more detail, cochlear organotypic cultures from postnatal day 3 rats were treated with paclitaxel for 24 or 48 h with doses ranging from 1 to 30 μM. No obvious histopathologies were observed after 24 h treatment with any of the paclitaxel doses employed, but with 48 h treatment, paclitaxel damaged cochlear hair cells in a dose-dependent manner and also damaged auditory nerve fibers and spiral ganglion neurons (SGN) near the base of the cochlea. TUNEL labeling was negative in the organ of Corti, but positive in SGN with karyorrhexis 48 h after 30 μM paclitaxel treatment. In addition, caspase-6, caspase-8 and caspase-9 labeling was present in SGN treated with 30 μM paclitaxel for 48 h. These results suggest that caspase-dependent apoptotic pathways are involved in paclitaxel-induced damage of SGN, but not hair cells in cochlea. - Highlights: • Paclitaxel was toxic to cochlear hair cells and spiral ganglion neurons. • Paclitaxel-induced spiral ganglion degeneration was apoptotic. • Paclitaxel activated caspase-6, -8 and -8 in spiral ganglion neurons.

  10. Dual-layer surface coating of PLGA-based nanoparticles provides slow-release drug delivery to achieve metronomic therapy in a paclitaxel-resistant murine ovarian cancer model.

    Science.gov (United States)

    Amoozgar, Zohreh; Wang, Lei; Brandstoetter, Tania; Wallis, Samuel S; Wilson, Erin M; Goldberg, Michael S

    2014-11-10

    Development of drug resistance is a central challenge to the treatment of ovarian cancer. Metronomic chemotherapy decreases the extent of drug-free periods, thereby hindering development of drug resistance. Intraperitoneal chemotherapy allows for treatment of tumors confined within the peritoneum, but achieving sustained tumor-localized chemotherapy remains difficult. We hypothesized that modulating the surface properties of poly(lactic-co-glycolic acid) (PLGA)-based nanoparticles could enhance their drug retention ability and extend their release profile, thereby enabling metronomic, localized chemotherapy in vivo. Paclitaxel was encapsulated in particles coated with a layer of polydopamine and a subsequent layer of poly(ethylene glycol) (PEG). These particles achieved a 3.8-fold higher loading content compared to that of nanoparticles formulated from linear PLGA-PEG copolymers. In vitro release kinetic studies and in vivo drug distribution profiles demonstrate sustained release of paclitaxel. Although free drug conferred no survival advantage, low-dose intraperitoneal administration of paclitaxel-laden surface-coated nanoparticles to drug-resistant ovarian tumor-bearing mice resulted in significant survival benefits in the absence of any apparent systemic toxicity.

  11. Comparison of cell death-inducing effect of novel taxane SB-T-1216 and paclitaxel in breast cancer cells

    Czech Academy of Sciences Publication Activity Database

    Kovář, J.; Ehrlichová, M.; Šmejkalová, Barbora; Zanardi, I.; Ojima, I.; Gut, I.

    2009-01-01

    Roč. 29, č. 8 (2009), s. 2951-2960 ISSN 0250-7005 R&D Projects: GA ČR(CZ) GD204/05/H023 Grant - others:GA MZd(CZ) NR9426; GA ČR(CZ) GA301/09/0362 Institutional research plan: CEZ:AV0Z50520514 Keywords : Cell death * taxane SB-T-1216 * paclitaxel Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.428, year: 2009

  12. TRPV1 receptors contribute to mediate paclitaxel-induced c-Fos expression in spinal cord dorsal horn neurons

    Czech Academy of Sciences Publication Activity Database

    Kalynovska, Nataliia; Adámek, Pavel; Paleček, Jiří

    2017-01-01

    Roč. 66, č. 3 (2017), s. 549-532 ISSN 0862-8408 R&D Projects: GA ČR(CZ) GA15-11138S; GA MŠk(CZ) LH15279; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:67985823 Keywords : c-Fos * paclitaxel * TRPV1 * neuropathy * spinal cord Subject RIV: FH - Neurology OBOR OECD: Neurosciences (including psychophysiology Impact factor: 1.461, year: 2016

  13. MicroRNA-128 suppresses paclitaxel-resistant lung cancer by inhibiting MUC1-C and BMI-1 in cancer stem cells.

    Science.gov (United States)

    Koh, Hyebin; Park, Hyeri; Chandimali, Nisansala; Huynh, Do Luong; Zhang, Jiao Jiao; Ghosh, Mrinmoy; Gera, Meeta; Kim, Nameun; Bak, Yesol; Yoon, Do-Young; Park, Yang Ho; Kwon, Taeho; Jeong, Dong Kee

    2017-12-15

    The existence of cancer stem cells (CSCs) is the main reason for failure of cancer treatment caused by drug resistance. Therefore, eradicating cancers by targeting CSCs remains a significant challenge. In the present study, because of the important role of BMI-1 proto-oncogene, polycomb ring finger (BMI-1) and C-terminal Mucin1 (MUC1-C) in tumor growth and maintenance of CSCs, we aimed to confirm that microRNA miR-128, as an inhibitor of BMI-1 and MUC1-C, could effectively suppress paclitaxel (PTX)-resistant lung cancer stem cells. We showed that CSCs have significantly higher expression levels of BMI-1, MUC1-C, stemness proteins, signaling factors, and higher malignancy compared with normal tumor cells. After transfection with miR-128, the BMI-1 and MUC1-C levels in CSCs were suppressed. When miR-128 was stably expressed in PTX-resistant lung cancer stem cells, the cells showed decreased proliferation, metastasis, self-renewal, migration, invasive ability, clonogenicity, and tumorigenicity in vitro and in vivo and increased apoptosis compared with miR-NC (negative control) CSCs. Furthermore, miR-128 effectively decreased the levels of β-catenin and intracellular signaling pathway-related factors in CSCs. MiR-128 also decreased the luciferase activity of MUC1 reporter constructs and reduced the levels of transmembrane MUC1-C and BMI-1. These results suggested miR-128 as an attractive therapeutic strategy for PTX-resistant lung cancer via inhibition of BMI-1 and MUC1-C.

  14. Development, optimization and evaluation of surfactant-based pulmonary nanolipid carrier system of paclitaxel for the management of drug resistance lung cancer using Box-Behnken design.

    Science.gov (United States)

    Kaur, Prabhjot; Garg, Tarun; Rath, Goutam; Murthy, R S Rayasa; Goyal, Amit K

    2016-07-01

    In the present study, nanostructured lipid carriers (NLCs) along with various surfactants loaded with paclitaxel (PTX) were prepared by an emulsification technique using a Box-Behnken design. The Box-Behnken design indicated that the most effective factors on the size and PDI were at high surfactant concentration (1.5%), low lipids ratio (6:4) and medium homogenization speed (6000 rpm). Among all the formulations, Tween 20-loaded NLCs show least particle size compared to Tween 80 and Tween 60. Entrapment efficiency of Tween 20, Tween 80 and Tween 60-loaded formulations were 82.40, 85.60 and 79.78%, respectively. Drug release of Tween 80, Tween 20 and Tween 60-loaded NLCs is 64.9, 62.3 and 59.7%, respectively (within 72 h). Maximum cellular uptake was observed with Tween 20 formulation on Caco-2 cell lines. Furthermore, spray drying of resultant NLCs was showed good flow properties and was selected for drug delivery to deeper airways. In-vivo studies demonstrated the better localization of drug within the lungs using different surfactant-based pulmonary delivery systems. From this study, we have concluded that delivering drugs through pulmonary route is advantageous for local action in lungs as maximum amount of drug concentration was observed in lungs. The surfactants could prove to be beneficial in treating drug resistance lung cancer by inhibiting P-gp efflux in the form of nano lipidic carriers.

  15. Paclitaxel and doxorubicin in metastatic breast cancer

    DEFF Research Database (Denmark)

    Gehl, J; Boesgaard, M; Paaske, T

    1996-01-01

    For the past decades the anthracyclines have been regarded as among the most active drugs for the treatment of metastatic breast cancer. However, the 5-year survival rate in patients with stage IV breast cancer continues to be below 20%, and new active drugs and drug combinations clearly must...... be explored. Paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) has been demonstrated to be highly effective in treating patients with advanced breast cancer, including those with anthracycline-resistant breast cancer, a fact that has led to efforts to combine paclitaxel and anthracyclines...

  16. Prodrug Strategies for Paclitaxel

    Directory of Open Access Journals (Sweden)

    Ziyuan Meng

    2016-05-01

    Full Text Available Paclitaxel is an anti-tumor agent with remarkable anti-tumor activity and wide clinical uses. However, it is also faced with various challenges especially for its poor water solubility and low selectivity for the target. To overcome these disadvantages of paclitaxel, approaches using small molecule modifications and macromolecule modifications have been developed by many research groups from all over the world. In this review, we discuss the different strategies especially prodrug strategies that are currently used to make paclitaxel more effective.

  17. Induced disease resistance signaling in plants

    NARCIS (Netherlands)

    Verhagen, B.W.M.; Loon, L.C. van; Pieterse, C.M.J.

    2006-01-01

    To protect themselves from disease, plants have evolved sophisticated inducible defense mechanisms in which the signal molecules salicylic acid, jasmonic acid and ethylene often play crucial roles. Elucidation of signaling pathways controlling induced disease resistance is a major objective in

  18. Covalent linkage of nanodiamond-paclitaxel for drug delivery and cancer therapy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Kuang-Kai; Wang, Chi-Ching; Chao, Jui-I [Department of Biological Science and Technology, National Chiao Tung University, Hsinchu 30013, Taiwan (China); Zheng, Wen-Wei; Lo, Yu-Shiu; Chen, Chinpiao [Department of Chemistry, National Dong Hwa University, Hualien 97401, Taiwan (China); Chiu, Yu-Chung; Cheng, Chia-Liang, E-mail: clcheng@mail.ndhu.edu.tw, E-mail: chinpiao@mail.ndhu.edu.tw, E-mail: jichao@faculty.nctu.edu.tw [Department of Physics, National Dong Hwa University, Hualien 97401, Taiwan (China)

    2010-08-06

    A nanoparticle-conjugated cancer drug provides a novel strategy for cancer therapy. In this study, we manipulated nanodiamond (ND), a carbon nanomaterial, to covalently link paclitaxel for cancer drug delivery and therapy. Paclitaxel was bound to the surface of 3-5 nm sized ND through a succession of chemical modifications. The ND-paclitaxel conjugation was measured by atomic force microscope and nuclear magnetic resonance spectroscopy, and confirmed with infrared spectroscopy by the detection of deuterated paclitaxel. Treatment with 0.1-50 {mu}g ml{sup -1} ND-paclitaxel for 48 h significantly reduced the cell viability in the A549 human lung carcinoma cells. ND-paclitaxel induced both mitotic arrest and apoptosis in A549 cells. However, ND alone or denatured ND-paclitaxel (after treatment with strong alkaline solution, 1 M NaOH) did not induce the damage effects on A549 cells. ND-paclitaxel was taken into lung cancer cells in a concentration-dependent manner using flow cytometer analysis. The ND-paclitaxel particles were located in the microtubules and cytoplasm of A549 cells observed by confocal microscopy. Furthermore, ND-paclitaxel markedly blocked the tumor growth and formation of lung cancer cells in xenograft SCID mice. Together, we provide a functional covalent conjugation of ND-paclitaxel, which can be delivered into lung carcinoma cells and preserves the anticancer activities on the induction of mitotic blockage, apoptosis and anti-tumorigenesis.

  19. CyclinG1 Amplification Enhances Aurora Kinase Inhibitor-Induced Polyploid Resistance and Inhibition of Bcl-2 Pathway Reverses the Resistance

    Directory of Open Access Journals (Sweden)

    Wenfeng Zhang

    2017-08-01

    Full Text Available Background/Aims: CyclinG1 (CycG1 is frequently overexpressed in solid tumors and overexpression of CycG1 promotes cell survival upon paclitaxel exposure by inducing polyploidy. Whether and how CycG1 regulates polyploidization caused by small molecular targeted inhibitors remains unclear. Methods: Immunohistochemistry and immunoblotting were utilized to examine protein expression. Cell proliferation was measured by ATPlite assay, and cell cycle distribution and apoptosis were measured by flow cytometry and/or DNA fragmentation assays. Results: Overexpression of CycG1 in breast cancer cells caused apoptosis-resistant polyploidy upon treatment with Aurora kinase inhibitor, ZM447439 (ZM. Addition of ABT-263, a small-molecule BH3 mimetic, to ZM, produced a synergistic loss of cell viability with greater sustained tumor growth inhibition in breast cancer cell lines. Decrease of Mcl-1 and increase of NOXA caused by ZM treatment, were responsible for the synergy. Furthermore, CycG1 was highly expressed in Triple-Negative-Breast-Cancer patients treated with paclitaxel and was paralleled by decreased cell survival. Conclusion: CycG1 is a crucial factor in ZM-induced polyploidy resistance, and ABT-263/ZM combination hold therapeutic utility in the CycG1-amplified subset of breast cancer and CycG1, thus, is a promising target in breast cancer.

  20. Resistance and sheet resistance measurements using electron beam induced current

    International Nuclear Information System (INIS)

    Czerwinski, A.; Pluska, M.; Ratajczak, J.; Szerling, A.; KaPtcki, J.

    2006-01-01

    A method for measurement of spatially uniform or nonuniform resistance in layers and strips, based on electron beam induced current (EBIC) technique, is described. High electron beam currents are used so that the overall resistance of the measurement circuit affects the EBIC signal. During the evaluation, the electron beam is scanned along the measured object, whose load resistance varies with the distance. The variation is compensated by an adjustable resistance within an external circuit. The method has been experimentally deployed for sheet resistance determination of buried regions of lateral confinements in semiconductor laser heterostructures manufactured by molecular beam epitaxy

  1. Protective Effect of Caffeic Acid on Paclitaxel Induced Anti-Proliferation and Apoptosis of Lung Cancer Cells Involves NF-κB Pathway

    Directory of Open Access Journals (Sweden)

    Yao Fong

    2012-05-01

    Full Text Available Caffeic acid (CA, a natural phenolic compound, is abundant in medicinal plants. CA possesses multiple biological effects such as anti-bacterial and anti-cancer growth. CA was also reported to induce fore stomach and kidney tumors in a mouse model. Here we used two human lung cancer cell lines, A549 and H1299, to clarify the role of CA in cancer cell proliferation. The growth assay showed that CA moderately promoted the proliferation of the lung cancer cells. Furthermore, pre-treatment of CA rescues the proliferation inhibition induced by a sub-IC50 dose of paclitaxel (PTX, an anticancer drug. Western blot showed that CA up-regulated the pro-survival proteins survivin and Bcl-2, the down-stream targets of NF-κB. This is consistent with the observation that CA induced nuclear translocation of NF-κB p65. Our study suggested that the pro-survival effect of CA on PTX-treated lung cancer cells is mediated through a NF-κB signaling pathway. This may provide mechanistic insights into the chemoresistance of cancer calls.

  2. Linking aboveground and belowground inducible plant resistance

    NARCIS (Netherlands)

    Bezemer, T.M.

    2009-01-01

    Induced resistance of plants against pests and diseases via plant defense responses is well documented and can occur aboveground, in the leaves, and belowground in the roots. A number of recent studies have shown that soil-borne pests can also induce plant resistance aboveground and vice versa.

  3. Clinical Pharmacokinetics of Paclitaxel Monotherapy

    DEFF Research Database (Denmark)

    Stage, Tore B; Bergmann, Troels K; Kroetz, Deanna L

    2018-01-01

    Paclitaxel is an anticancer agent efficacious in the treatment of ovarian, breast, and lung cancer. Due to a strong link between the pharmacokinetics and therapeutic efficacy of paclitaxel, we reviewed the literature on paclitaxel pharmacokinetics. Systematic data mining was performed to extract ...

  4. Cannabidiol inhibits paclitaxel-induced neuropathic pain through 5-HT(1A) receptors without diminishing nervous system function or chemotherapy efficacy.

    Science.gov (United States)

    Ward, Sara Jane; McAllister, Sean D; Kawamura, Rumi; Murase, Ryuchi; Neelakantan, Harshini; Walker, Ellen A

    2014-02-01

    Paclitaxel (PAC) is associated with chemotherapy-induced neuropathic pain (CIPN) that can lead to the cessation of treatment in cancer patients even in the absence of alternate therapies. We previously reported that chronic administration of the non-psychoactive cannabinoid cannabidiol (CBD) prevents PAC-induced mechanical and thermal sensitivity in mice. Hence, we sought to determine receptor mechanisms by which CBD inhibits CIPN and whether CBD negatively effects nervous system function or chemotherapy efficacy. The ability of acute CBD pretreatment to prevent PAC-induced mechanical sensitivity was assessed, as was the effect of CBD on place conditioning and on an operant-conditioned learning and memory task. The potential interaction of CBD and PAC on breast cancer cell viability was determined using the MTT assay. PAC-induced mechanical sensitivity was prevented by administration of CBD (2.5 - 10 mg·kg⁻¹) in female C57Bl/6 mice. This effect was reversed by co-administration of the 5-HT(1A) antagonist WAY 100635, but not the CB₁ antagonist SR141716 or the CB₂ antagonist SR144528. CBD produced no conditioned rewarding effects and did not affect conditioned learning and memory. Also, CBD + PAC combinations produce additive to synergistic inhibition of breast cancer cell viability. Our data suggest that CBD is protective against PAC-induced neurotoxicity mediated in part by the 5-HT(1A) receptor system. Furthermore, CBD treatment was devoid of conditioned rewarding effects or cognitive impairment and did not attenuate PAC-induced inhibition of breast cancer cell viability. Hence, adjunct treatment with CBD during PAC chemotherapy may be safe and effective in the prevention or attenuation of CIPN. © 2013 The British Pharmacological Society.

  5. Cannabidiol inhibits paclitaxel-induced neuropathic pain through 5-HT1A receptors without diminishing nervous system function or chemotherapy efficacy

    Science.gov (United States)

    Ward, Sara Jane; McAllister, Sean D; Kawamura, Rumi; Murase, Ryuchi; Neelakantan, Harshini; Walker, Ellen A

    2014-01-01

    Background and Purpose Paclitaxel (PAC) is associated with chemotherapy-induced neuropathic pain (CIPN) that can lead to the cessation of treatment in cancer patients even in the absence of alternate therapies. We previously reported that chronic administration of the non-psychoactive cannabinoid cannabidiol (CBD) prevents PAC-induced mechanical and thermal sensitivity in mice. Hence, we sought to determine receptor mechanisms by which CBD inhibits CIPN and whether CBD negatively effects nervous system function or chemotherapy efficacy. Experimental Approach The ability of acute CBD pretreatment to prevent PAC-induced mechanical sensitivity was assessed, as was the effect of CBD on place conditioning and on an operant-conditioned learning and memory task. The potential interaction of CBD and PAC on breast cancer cell viability was determined using the MTT assay. Key Results PAC-induced mechanical sensitivity was prevented by administration of CBD (2.5 – 10 mg·kg−1) in female C57Bl/6 mice. This effect was reversed by co-administration of the 5-HT1A antagonist WAY 100635, but not the CB1 antagonist SR141716 or the CB2 antagonist SR144528. CBD produced no conditioned rewarding effects and did not affect conditioned learning and memory. Also, CBD + PAC combinations produce additive to synergistic inhibition of breast cancer cell viability. Conclusions and Implications Our data suggest that CBD is protective against PAC-induced neurotoxicity mediated in part by the 5-HT1A receptor system. Furthermore, CBD treatment was devoid of conditioned rewarding effects or cognitive impairment and did not attenuate PAC-induced inhibition of breast cancer cell viability. Hence, adjunct treatment with CBD during PAC chemotherapy may be safe and effective in the prevention or attenuation of CIPN. PMID:24117398

  6. Graphene oxide stabilized by PLA-PEG copolymers for the controlled delivery of paclitaxel.

    Science.gov (United States)

    Angelopoulou, A; Voulgari, E; Diamanti, E K; Gournis, D; Avgoustakis, K

    2015-06-01

    To investigate the application of water-dispersible poly(lactide)-poly(ethylene glycol) (PLA-PEG) copolymers for the stabilization of graphene oxide (GO) aqueous dispersions and the feasibility of using the PLA-PEG stabilized GO as a delivery system for the potent anticancer agent paclitaxel. A modified Staudenmaier method was applied to synthesize graphene oxide (GO). Diblock PLA-PEG copolymers were synthesized by ring-opening polymerization of dl-lactide in the presence of monomethoxy-poly(ethylene glycol) (mPEG). Probe sonication in the presence of PLA-PEG copolymers was applied in order to reduce the hydrodynamic diameter of GO to the nano-size range according to dynamic light scattering (DLS) and obtain nano-graphene oxide (NGO) composites with PLA-PEG. The composites were characterized by atomic force microscopy (AFM), thermogravimetric analysis (TGA), and DLS. The colloidal stability of the composites was evaluated by recording the size of the composite particles with time and the resistance of composites to aggregation induced by increasing concentrations of NaCl. The composites were loaded with paclitaxel and the in vitro release profile was determined. The cytotoxicity of composites against A549 human lung cancer cells in culture was evaluated by flow cytometry. The uptake of FITC-labeled NGO/PLA-PEG by A549 cells was also estimated with flow cytometry and visualized with fluorescence microscopy. The average hydrodynamic diameter of NGO/PLA-PEG according to DLS ranged between 455 and 534 nm, depending on the molecular weight and proportion of PLA-PEG in the composites. NGO/PLA-PEG exhibited high colloidal stability on storage and in the presence of high concentrations of NaCl (far exceeding physiological concentrations). Paclitaxel was effectively loaded in the composites and released by a highly sustained fashion. Drug release could be regulated by the molecular weight of the PLA-PEG copolymer and its proportion in the composite. The paclitaxel

  7. Fe3O4 nanoparticle loaded paclitaxel induce multiple myeloma apoptosis by cell cycle arrest and increase cleavage of caspases in vitro

    Science.gov (United States)

    Yang, Cuiping; He, Xiangfeng; Chen, Junsong; Chen, Dengyu; Liu, Yunjing; Xiong, Fei; Shi, Fangfang; Dou, Jun; Gu, Ning

    2013-08-01

    Multiple myeloma (MM) still remains an incurable disease in spite of extending the patient survival by new therapies. The hypothesis of cancer stem cells (CSCs) states that although chemotherapy kills most tumor cells, it is believed to leave a reservoir of CSCs that allows the tumor cell propagation. The objective of this research was to evaluate the therapeutic effect of new paclitaxel-Fe3O4 nanoparticles (PTX-NPs) with an average size range of 7.17 ± 1.31 nm on MM CSCs in vitro. The characteristics of CD138-CD34- cells, isolated from human MM RPMI 8226 and NCI-H929 cell lines by the magnetic associated cell sorting method, were identified by the assays of colony formation, cell proliferation, drug resistance, cell migration, and tumorigenicity in non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice, respectively. Inhibitory effects of PTX-NPs on CD138-CD34- cells were evaluated by a variety of assays in vitro. The results showed that the CD138-CD34- cells were capable of forming colonies, exhibited high proliferative and migratory ability, possessed a strong drug resistance, and had powerful tumorigenicity in NOD/SCID mice compared to non-CD138-CD34- cells. PTX-NPs significantly inhibited CD138- CD34- cell viability and invasive ability, and resulted in G0/G1 cell cycle arrest and apoptosis compared with PTX alone. We concluded that the CD138-CD34- phenotype cells might be CSCs in RPMI 8226 and NCI-H929 cell lines. PTX-NPs had an obvious inhibitory effect on MM CD138-CD34- CSCs. The findings may provide a guideline for PTX-NPs' treatment of MM CSCs in preclinical investigation.

  8. Fe{sub 3}O{sub 4} nanoparticle loaded paclitaxel induce multiple myeloma apoptosis by cell cycle arrest and increase cleavage of caspases in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Cuiping [Medical School, Southeast University, Department of Pathogenic Biology and Immunology (China); He, Xiangfeng [Affiliated Tumor Hospital of Nantong University, Department of Medical Oncology (China); Chen, Junsong; Chen, Dengyu; Liu, Yunjing [Medical School, Southeast University, Department of Pathogenic Biology and Immunology (China); Xiong, Fei [Southeast University, School of Biological Science and Medical Engineering (China); Shi, Fangfang [Zhongda Hospital, Southeast University, Department of Oncology (China); Dou, Jun, E-mail: njdoujun@yahoo.com.cn [Medical School, Southeast University, Department of Pathogenic Biology and Immunology (China); Gu, Ning, E-mail: guning@seu.edu.cn [Southeast University, School of Biological Science and Medical Engineering (China)

    2013-08-15

    Multiple myeloma (MM) still remains an incurable disease in spite of extending the patient survival by new therapies. The hypothesis of cancer stem cells (CSCs) states that although chemotherapy kills most tumor cells, it is believed to leave a reservoir of CSCs that allows the tumor cell propagation. The objective of this research was to evaluate the therapeutic effect of new paclitaxel-Fe{sub 3}O{sub 4} nanoparticles (PTX-NPs) with an average size range of 7.17 {+-} 1.31 nm on MM CSCs in vitro. The characteristics of CD138{sup -}CD34{sup -} cells, isolated from human MM RPMI 8226 and NCI-H929 cell lines by the magnetic associated cell sorting method, were identified by the assays of colony formation, cell proliferation, drug resistance, cell migration, and tumorigenicity in non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice, respectively. Inhibitory effects of PTX-NPs on CD138{sup -}CD34{sup -} cells were evaluated by a variety of assays in vitro. The results showed that the CD138{sup -}CD34{sup -} cells were capable of forming colonies, exhibited high proliferative and migratory ability, possessed a strong drug resistance, and had powerful tumorigenicity in NOD/SCID mice compared to non-CD138{sup -}CD34{sup -} cells. PTX-NPs significantly inhibited CD138{sup -} CD34{sup -} cell viability and invasive ability, and resulted in G0/G1 cell cycle arrest and apoptosis compared with PTX alone. We concluded that the CD138{sup -}CD34{sup -} phenotype cells might be CSCs in RPMI 8226 and NCI-H929 cell lines. PTX-NPs had an obvious inhibitory effect on MM CD138{sup -}CD34{sup -} CSCs. The findings may provide a guideline for PTX-NPs' treatment of MM CSCs in preclinical investigation.

  9. Fe3O4 nanoparticle loaded paclitaxel induce multiple myeloma apoptosis by cell cycle arrest and increase cleavage of caspases in vitro

    International Nuclear Information System (INIS)

    Yang, Cuiping; He, Xiangfeng; Chen, Junsong; Chen, Dengyu; Liu, Yunjing; Xiong, Fei; Shi, Fangfang; Dou, Jun; Gu, Ning

    2013-01-01

    Multiple myeloma (MM) still remains an incurable disease in spite of extending the patient survival by new therapies. The hypothesis of cancer stem cells (CSCs) states that although chemotherapy kills most tumor cells, it is believed to leave a reservoir of CSCs that allows the tumor cell propagation. The objective of this research was to evaluate the therapeutic effect of new paclitaxel-Fe 3 O 4 nanoparticles (PTX-NPs) with an average size range of 7.17 ± 1.31 nm on MM CSCs in vitro. The characteristics of CD138 − CD34 − cells, isolated from human MM RPMI 8226 and NCI-H929 cell lines by the magnetic associated cell sorting method, were identified by the assays of colony formation, cell proliferation, drug resistance, cell migration, and tumorigenicity in non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice, respectively. Inhibitory effects of PTX-NPs on CD138 − CD34 − cells were evaluated by a variety of assays in vitro. The results showed that the CD138 − CD34 − cells were capable of forming colonies, exhibited high proliferative and migratory ability, possessed a strong drug resistance, and had powerful tumorigenicity in NOD/SCID mice compared to non-CD138 − CD34 − cells. PTX-NPs significantly inhibited CD138 − CD34 − cell viability and invasive ability, and resulted in G0/G1 cell cycle arrest and apoptosis compared with PTX alone. We concluded that the CD138 − CD34 − phenotype cells might be CSCs in RPMI 8226 and NCI-H929 cell lines. PTX-NPs had an obvious inhibitory effect on MM CD138 − CD34 − CSCs. The findings may provide a guideline for PTX-NPs’ treatment of MM CSCs in preclinical investigation

  10. Inducible Clindamycin Resistance in Staphylococcus Species

    International Nuclear Information System (INIS)

    Afridi, F. I.; Zeb, M.; Farooqi, B. J.; Murtaza, G.; Hussain, A.

    2014-01-01

    Objective: To determine the frequency of inducible clindamycin resistance in clinical isolates of Staphylococcus species by phenotypic D-test. Study Design: Observational study. Place and Duration of Study: Ziauddin University Hospital, Karachi, from July to December 2011. Methodology: Consecutive clinical isolates of Staphylococcus species were collected and identified by conventional microbiological techniques. Antimicrobial susceptibility testing and inducible clindamycin resistance was carried out by performing D-test using CLSI criteria. Methicillin resistance was detected by using Cefoxitin disk as a surrogate marker. Statistical analysis was performed by SPSS version-17. Results: A total of 667 clinical isolates of Staphylococcus species were obtained during the study period. In these isolates, 177 (26.5%) were Staphylococcus aureus, and 490 (73.5%) were coagulase negative Staphylococci. The total frequency of inducible clindamycin resistance among isolates of Staphylococcus species was 120/667 (18%). Frequency of inducible clindamycin resistance among coagulase negative Staphylococci group and Staphylococcus aureus group were 18.57% and 16.38% respectively. Median age of patients in D-test positive group was 19.5 (1 - 54) years. Conclusion: The frequency of inducible clindamycin resistance among Staphylococcus species may differ in different hospital setup. Clinical microbiology laboratories should implement testing simple and effective D-test on all Staphylococcus species. D-test positive isolates should be reported clindamycin resistant to decrease treatment failure. (author)

  11. Efficacy of aprepitant for the prevention of chemotherapy-induced nausea and vomiting with a moderately emetogenic chemotherapy regimen: a multicenter, placebo-controlled, double-blind, randomized study in patients with gynecologic cancer receiving paclitaxel and carboplatin.

    Science.gov (United States)

    Yahata, Hideaki; Kobayashi, Hiroaki; Sonoda, Kenzo; Shimokawa, Mototsugu; Ohgami, Tatsuhiro; Saito, Toshiaki; Ogawa, Shinji; Sakai, Kunihiro; Ichinoe, Akimasa; Ueoka, Yousuke; Hasuo, Yasuyuki; Nishida, Makoto; Masuda, Satohiro; Kato, Kiyoko

    2016-06-01

    Substance P contributes to the hypersensitivity reaction (HSR) to paclitaxel in a rat model. Aprepitant acts as an inhibitor of the binding of substance P to the neurokinin-1 receptor and, consequently, may reduce the frequency of paclitaxel-induced HSR. While aprepitant has a prophylactic effect against vomiting caused by high-dose cisplatin, the benefits of aprepitant have not been clearly demonstrated in patients receiving paclitaxel and carboplatin (TC) combination chemotherapy. We conducted a multicenter, placebo-controlled, double-blind, randomized study in Japanese patients with gynecologic cancer who received TC combination chemotherapy. Patients received aprepitant or placebo together with both a 5-HT3 receptor antagonist and dexamethasone prior to chemotherapy. The primary endpoint was the proportion of patients with HSR, and the secondary endpoints were the proportion of patients with "no vomiting", "no significant nausea", and complete response, respectively. Of the 324 randomized patients, 297 (151 in the aprepitant group; 146 in the placebo group) were evaluated. The percentage of patients with HSR (9.2 vs. 7.5 %, respectively; P = 0.339) was not significantly different between the groups. The percentage of "no vomiting" patients (78.2 vs. 54.8 %; P gynecologic cancer patients receiving TC combination chemotherapy.

  12. Inhibition of the Receptor Tyrosine Kinase AXL Restores Paclitaxel Chemosensitivity in Uterine Serous Cancer.

    Science.gov (United States)

    Palisoul, Marguerite L; Quinn, Jeanne M; Schepers, Emily; Hagemann, Ian S; Guo, Lei; Reger, Kelsey; Hagemann, Andrea R; McCourt, Carolyn K; Thaker, Premal H; Powell, Matthew A; Mutch, David G; Fuh, Katherine C

    2017-12-01

    Uterine serous cancer (USC) is aggressive, and the majority of recurrent cases are chemoresistant. Because the receptor tyrosine kinase AXL promotes invasion and metastasis of USC and is implicated in chemoresistance in other cancers, we assessed the role of AXL in paclitaxel resistance in USC, determined the mechanism of action, and sought to restore chemosensitivity by inhibiting AXL in vitro and in vivo We used short hairpin RNAs and BGB324 to knock down and inhibit AXL. We assessed sensitivity of USC cell lines to paclitaxel and measured paclitaxel intracellular accumulation in vitro in the presence or absence of AXL. We also examined the role of the epithelial-mesenchymal transition (EMT) in AXL-mediated paclitaxel resistance. Finally, we treated USC xenografts with paclitaxel, BGB324, or paclitaxel plus BGB324 and monitored tumor burden. AXL expression was higher in chemoresistant USC patient tumors and cell lines than in chemosensitive tumors and cell lines. Knockdown or inhibition of AXL increased sensitivity of USC cell lines to paclitaxel in vitro and increased cellular accumulation of paclitaxel. AXL promoted chemoresistance even in cells that underwent the EMT in vitro Finally, in vivo studies of combination treatment with BGB324 and paclitaxel showed a greater than 51% decrease in tumor volume after 2 weeks of treatment when compared with no treatment or single-agent treatments ( P USC. Mol Cancer Ther; 16(12); 2881-91. ©2017 AACR . ©2017 American Association for Cancer Research.

  13. Low doses of Paclitaxel repress breast cancer invasion through DJ-1/KLF17 signalling pathway.

    Science.gov (United States)

    Ismail, Ismail Ahmed; El-Sokkary, Gamal H; Saber, Saber H

    2018-04-27

    Paclitaxel (taxol) is an important agent against many tumours, including breast cancer. Ample data documents that paclitaxel inhibits breast cancer metastasis while others prove that paclitaxel enhances breast cancer metastasis. The mechanisms by which paclitaxel exerts its action are not well established. This study focuses on the effect of paclitaxel, particularly the low doses on breast cancer metastasis and the mechanisms that regulate it. Current results show that, paclitaxel exerts significant cytotoxicity even at low doses in both MCF-7 and MDA-MB-231 cells. Interestingly, paclitaxel significantly inhibits cell invasion and migration, decreases Snail and increases E-cadherin mRNA expression levels at the indicated low doses. Furthermore, paclitaxel-inhibiting breast cancer metastasis is associated with down-regulation of DJ-1 and ID-1 mRNA expression level with a concurrent increase in KLF17 expression. Under the same experimental conditions, paclitaxel induces KLF17 and concurrently represses ID-1 protein levels. Our results show for the first time that paclitaxel inhibits breast cancer metastasis through regulating DJ-1/KLF17/ID-1 signalling pathway; repressed DJ-1 and ID-1 and enhanced KLF17 expression. © 2018 John Wiley & Sons Australia, Ltd.

  14. Rationalization of paclitaxel insensitivity of yeast β-tubulin and human βIII-tubulin isotype using principal component analysis

    Directory of Open Access Journals (Sweden)

    Das Lalita

    2012-08-01

    Full Text Available Abstract Background The chemotherapeutic agent paclitaxel arrests cell division by binding to the hetero-dimeric protein tubulin. Subtle differences in tubulin sequences, across eukaryotes and among β-tubulin isotypes, can have profound impact on paclitaxel-tubulin binding. To capture the experimentally observed paclitaxel-resistance of human βIII tubulin isotype and yeast β-tubulin, within a common theoretical framework, we have performed structural principal component analyses of β-tubulin sequences across eukaryotes. Results The paclitaxel-resistance of human βIII tubulin isotype and yeast β-tubulin uniquely mapped on to the lowest two principal components, defining the paclitaxel-binding site residues of β-tubulin. The molecular mechanisms behind paclitaxel-resistance, mediated through key residues, were identified from structural consequences of characteristic mutations that confer paclitaxel-resistance. Specifically, Ala277 in βIII isotype was shown to be crucial for paclitaxel-resistance. Conclusions The present analysis captures the origin of two apparently unrelated events, paclitaxel-insensitivity of yeast tubulin and human βIII tubulin isotype, through two common collective sequence vectors.

  15. Ghrelin- and GH-induced insulin resistance

    DEFF Research Database (Denmark)

    Vestergaard, Esben Thyssen; Krag, Morten B; Poulsen, Morten M

    2013-01-01

    Supraphysiological levels of ghrelin and GH induce insulin resistance. Serum levels of retinol-binding protein-4 (RBP4) correlate inversely with insulin sensitivity in patients with type 2 diabetes. We aimed to determine whether ghrelin and GH affect RBP4 levels in human subjects.......Supraphysiological levels of ghrelin and GH induce insulin resistance. Serum levels of retinol-binding protein-4 (RBP4) correlate inversely with insulin sensitivity in patients with type 2 diabetes. We aimed to determine whether ghrelin and GH affect RBP4 levels in human subjects....

  16. Peripheral neuropathy due to therapy with paclitaxel, gemcitabine, and cisplatin in patients with advanced ovarian cancer.

    NARCIS (Netherlands)

    Verstappen, C.C.P.; Postma, T.J.; Hoekman, K.; Heimans, J.J.

    2003-01-01

    BACKGROUND: To evaluate the peripheral neuropathic changes induced by combination chemotherapy including paclitaxel (taxol), gemcitabine and cisplatin (TGC regimen). PATIENTS AND METHODS: Eighteen patients with primary or recurrent ovarian cancer were treated with paclitaxel 150 or 110 mg/m2,

  17. Induced resistance to rust disease in lentil

    International Nuclear Information System (INIS)

    Paul, Amitava; Singh, D.P.

    2006-01-01

    Considerable yield reduction in lentil is due to rust caused by Uromyces fabae. So far the sources of resistance to rust are available in the small seeded background. There is a need to develop rust resistant/tolerant bold seeded cultivars. Mutations were induced by gamma rays (10 and 15 kR) for incorporating resistance to rust in K-75(Mallika), a high yielding bold seeded, but rust susceptible cultivar at Pantnagar which is the hot spot for this disease. Dry seeds (300) were irradiated for each treatment. In M 1 generation, individual plants from each treatment were selfed and harvested separately which constituted the M 2 generation. In M 2 individual plant progenies were scored following a rating scale of 1 (Free) to 9(highly susceptible). At 15 kR dose, 8 plants were resistant (score 3.0) and 14 plants were tolerant (score 5.0) to rust, while in control and 10 kR populations, all plants were susceptible or highly susceptible having score of 7 or 9, respectively. The M 2 plants segregated in ratio of 1 resistant: 3 susceptible. The progenies of resistant/tolerant M 2 plants were bred true in the M 3 generation suggesting that the resistance to rust is controlled by one recessive gene. (author)

  18. Effect of paclitaxel (TAXOL) alone and in combination with radiation on the gastrointestinal mucosa

    International Nuclear Information System (INIS)

    Mason, K.A.; Milas, L.; Peters, L.J.

    1995-01-01

    Paclitaxel is a potentially useful drug for augmenting the cytotoxic action of radiotherapy because it has independent cytotoxic activity against certain cancers and blocks cells in the radiosensitive mitotic phase of the cell cycle. However, all rapidly proliferating tissues, both normal and neoplastic, may be affected by this therapeutic strategy. The aim of this study was to define the in vivo response of rapidly dividing cells of the small bowel mucosa in mice to paclitaxel given alone and in combination with radiation. Paclitaxel blocked jejunal crypt cells in mitosis and induced apoptosis in a dose-dependent manner. Fractionating the paclitaxel dose over 1-4 days did not result in any greater accumulation of mitotically blocked cells than did a single dose. Mitosis peaked 2-4 h after paclitaxel and returned to near normal by 24 h. Apoptosis lagged several hours behind mitosis and peaked about 6 h later than mitosis. Despite these kinetic perturbations, there was little or no enhancement of radiation effect when single doses were delivered 2-4 h after paclitaxel administration. The maximum sensitizer enhancement ratio of 1.07 observed after a single paclitaxel dose of 40 mg/kg is consistent with independent crypt cell killing. Conversely, when radiation was given 24 h after paclitaxel, a significant protective effect of the drug (SER 0.89-0.92), most probably due to a regenerative overshoot induced by paclitaxel, was observed. Stem cells of the jejunal mucosa determining radiation response were not radiosensitized by paclitaxel with the drug concentrations and dose deliver schedules used, although additive cytotoxicity was observed with the highest drug dose. A radioprotective effect was observed when radiation was given 24 h after paclitaxel administration. 33 refs., 4 figs., 3 tabs

  19. Praziquantel synergistically enhances paclitaxel efficacy to inhibit cancer cell growth.

    Directory of Open Access Journals (Sweden)

    Zhen Hua Wu

    Full Text Available The major challenges we are facing in cancer therapy with paclitaxel (PTX are the drug resistance and severe side effects. Massive efforts have been made to overcome these clinical challenges by combining PTX with other drugs. In this study, we reported the first preclinical data that praziquantel (PZQ, an anti-parasite agent, could greatly enhance the anticancer efficacy of PTX in various cancer cell lines, including PTX-resistant cell lines. Based on the combination index value, we demonstrated that PZQ synergistically enhanced PTX-induced cell growth inhibition. The co-treatment of PZQ and PTX also induced significant mitotic arrest and activated the apoptotic cascade. Moreover, PZQ combined with PTX resulted in a more pronounced inhibition of tumor growth compared with either drug alone in a mouse xenograft model. We tried to investigate the possible mechanisms of this synergistic efficacy induced by PZQ and PTX, and we found that the co-treatment of the two drugs could markedly decrease expression of X-linked inhibitor of apoptosis protein (XIAP, an anti-apoptotic protein. Our data further demonstrated that down-regulation of XIAP was required for the synergistic interaction between PZQ and PTX. Together, this study suggested that the combination of PZQ and PTX may represent a novel and effective anticancer strategy for optimizing PTX therapy.

  20. Paclitaxel: new uses for an old drug

    Directory of Open Access Journals (Sweden)

    Zhang D

    2014-02-01

    Full Text Available Dongshan Zhang,1,2 Ruhao Yang,1 Shixuan Wang,2 Zheng Dong1,2 1Departments of Emergency Medicine and Nephrology, Second Xiangya Hospital, Central South University, Changsha, Hunan, People’s Republic of China; 2Department of Cellular Biology and Anatomy, Medical College of Georgia, Georgia Regents University and Charlie Norwood VA Medical Center, Augusta, GA, USA Abstract: Paclitaxel (Taxol, one of the most important anticancer drugs, has been used for therapy of different types of cancers. Mechanistically, paclitaxel arrests cell cycle and induces cell death by stabilizing microtubules and interfering with microtubule disassembly in cell division. Recently, it has been found that low-dose paclitaxel seems promising in treating non-cancer diseases, such as skin disorders, renal and hepatic fibrosis, inflammation, axon regeneration, limb salvage, and coronary artery restenosis. Future studies need to understand the mechanisms underlying these effects in order to design therapies with specificity. Keywords: taxol inflammation, fibrosis, coronary artery restenosis, limb salvage, kidney

  1. Fluxon induced resistance and field emission

    CERN Document Server

    Calatroni, Sergio; Darriulat, Pierre; Peck, M A; Valente, A M; Van't Hof, C A

    2000-01-01

    The surface resistance of superconducting niobium films induced by the presence of trapped magnetic flux, presumably in the form of a pinned fluxon lattice, is shown to be modified by the presence of a field emitting impurity or defect. The modification takes the form of an additional surface resistance proportional to the density of the fluxon lattice and increasing linearly with the amplitude of the microwave above a threshold significantly lower than the field emission threshold. Such an effect, precursor of electron emission, is observed here for the first time in a study using radiofrequency cavities operated at their fundamental 1.5 GHz frequency. The measured properties of the additional surface resistance severely constrain possible explanations of the observed effect.

  2. Cannabidiol Prevents the Development of Cold and Mechanical Allodynia in Paclitaxel-Treated Female C57Bl6 Mice

    OpenAIRE

    Ward, Sara Jane; Ramirez, Michael David; Neelakantan, Harshini; Walker, Ellen Ann

    2011-01-01

    The taxane chemotherapeutic paclitaxel frequently produces peripheral neuropathy in humans. Rodent models to investigate mechanisms and treatments are largely restricted to male rats, whereas female mouse studies are lacking. We characterized a range of paclitaxel doses on cold and mechanical allodynia in male and female C57Bl/6 mice. Because the nonpsycho-active phytocannabinoid cannabidiol attenuates other forms of neuropathic pain, we assessed its effect on paclitaxel-induced allodynia. Pa...

  3. Induced thermal resistance in the mouse ear

    International Nuclear Information System (INIS)

    Law, M.P.; Coultas, P.G.; Field, S.B.

    1979-01-01

    The mouse ear (pinna) was used to investigate the effect of two hyperthermic treatments. Heating was by immersion in hot water at 43.5 0 C. A single treatment of about 50 minutes was required to cause necrosis in 50% of the ears treated. When heat treatment was given in two equal fractions the total heating time had to be increased if the interval between fractions was greater than four hours. By 24 hours a total treatment of about 100 minutes was required, indicating almost complete recovery from the first heating. Priming treatments at 43.5 0 C induced thermal resistance to a second heat treatment at 43.5 0 C. Maximum resistance was observed one day after a 20 minute priming and two days after a 40 minute priming, when the heating time had to be increased to 120 minutes, an increase by a factor of 2.4. Shorter priming treatments induced less resistance, the minimum heating time to produce an effect being two minutes. In all cases the effect decreased during the next four to five days. These results indicate that the reduced response of tissues to fractionated hyperthermia is due both to the repair of sublethal heat damage and induction of thermal resistance. (author)

  4. Nanoparticle albumin-bound paclitaxel: a novel Cremphor-EL-free formulation of paclitaxel.

    Science.gov (United States)

    Stinchcombe, Thomas E

    2007-08-01

    Standard formulation paclitaxel requires the use of solvents, such as Cremphor-EL, which contribute to some of the toxicities commonly associated with paclitaxel-based therapy. Nanoparticle albumin-bound paclitaxel (nab-paclitaxel) is a novel solvent-free formulation of paclitaxel. The formulation is prepared by high-pressure homogenization of paclitaxel in the presence of serum albumin into a nanoparticle colloidal suspension. The human albumin-stabilized paclitaxel particles have an average size of 130 nm. Nab-paclitaxel has several practical advantages over Cremphor-EL-paclitaxel, including a shorter infusion time (30 min) and no need for premedications for hypersensitivity reactions. The nab-paclitaxel formulation eliminates the impact of Cremphor-EL on paclitaxel pharmacokinetics and utilizes the endogenous albumin transport mechanisms to concentrate nab-paclitaxel within the tumor. A recent Phase III trial compared nab- and Cremphor-EL-paclitaxel in patients with metastatic breast cancer. Patients treated with nab-paclitaxel experienced a higher response, longer time to tumor progression and, in patients receiving second-line or greater therapy, a longer median survival. Patients treated with nab-paclitaxel had a significantly lower rate of severe neutropenia and a higher rate of sensory neuropathy. The preclinical and clinical data indicate that the nab-paclitaxel formulation has significant advantages over Cremphor-EL-paclitaxel.

  5. Effect of Paclitaxel (Taxol) alone and in combination with radiation on the gastrointestinal mucosa

    International Nuclear Information System (INIS)

    Mason, Kathryn Ann; Milas, Luka; Peters, Lester J.

    1995-01-01

    Purpose: Paclitaxel is a potentially useful drug for augmenting the cytotoxic action of radiotherapy because it has independent cytotoxic activity against certain cancers and blocks cells in the radiosensitive mitotic phase of the cell cycle. However, all rapidly proliferating tissues, both normal and neoplastic, may be affected by this therapeutic strategy. The aim of this study was to define the in vivo response of rapidly dividing cells of the small bowel mucosa to paclitaxel given alone and in combination with radiation. Methods and Materials: Mice were given single IV doses of 10 or 40 mg/kg paclitaxel or four doses of 10 mg/kg paclitaxel at 6, 12, or 24 h intervals. The kinetics of mitotic arrest and apoptosis in jejunal crypts of mice at 1-24 h after treatment were defined histologically. An in vivo stem cell microcolony assay was used to assess the radiosensitizing potential of paclitaxel when radiation was delivered at the peak of mitosis and at 24 h after drug treatment. Results: Paclitaxel blocked jejunal crypt cells in mitosis and induced apoptosis in a dose-dependent manner. Fractionating the paclitaxel dose over 1-4 days did not result in any greater accumulation of mitotically blocked cells than did a single dose. Mitosis peaked 2-4 h after paclitaxel and returned to near normal by 24 h. Apoptosis lagged several hours behind mitosis and peaked about 6 h later than mitosis. Despite these kinetic perturbations, there was little or no enhancement of radiation effect when single doses were delivered 2-4 h after paclitaxel administration. The maximum sensitizer enhancement ratio of 1.07 observed after a single paclitaxel dose of 40 mg/kg is consistent with independent crypt cell killing. Conversely, when radiation was given 24 h after paclitaxel, a significant protective effect of the drug (SER 0.89-0.92), most probably due to a regenerative overshoot induced by paclitaxel, was observed. Conclusion: Stem cells of the jejunal mucosa determining radiation

  6. LBA50 - Influence of concomitant clopidogrel consumption on development of paclitaxel-associated toxicity: A pharmacoepidemiological study

    DEFF Research Database (Denmark)

    K, Agergaard; Mau-Sørensen, M; Stage, Tore Bjerregaard

    clopidogrel to a metabolite, which is a strong inhibitor of CYP2C8. To determine if this interaction has clinical relevance, we investigated whether concomitant clopidogrel and paclitaxel was associated with severe paclitaxel toxicity, primarily peripheral sensory neuropathy. Methods Patients concomitantly...... from medical charts by reviewers partially blinded to clopidogrel exposure. The association of clopidogrel use and development of paclitaxel induced neuropathy was evaluated over accumulated paclitaxel dose with censoring after 1500 mg using Cox-regression analysis with adjustment for high intensity...... neuropathy or worse. Clopidogrel use was associated with increased risk of neuropathy with hazard ratios of 1.7 (95% CI 0.9-3.0), 2.0 (1.0-3.9) and 2.3 (1.1-4.5) in overall unadjusted, high intensity paclitaxel unadjusted and high intensity paclitaxel full adjusted analyses, respectively. Conclusions...

  7. Induced mutation for tungro resistance in rice

    International Nuclear Information System (INIS)

    Ikeda, R.; Yumol, R.R.; Taura, S.

    2001-01-01

    Tungro is the most serious virus disease of rice in South and Southeast Asia. It is a composite disease of two kinds of viruses, rice tungro bacilliform virus (RTBV) and rice tungro spherical virus (RTSV). Damage to the plant is mostly caused by RTBV, while RTSV acts to facilitate RTBV acquisition and transmission by insect vector. Both viruses are transmitted mainly by green leafhopper (GLH). Resistance to GLH is common in rice germplasm but extremely rare for the two viruses. To induce mutations for tungro resistance, a susceptible variety IR22 was treated with N-methyl-N-nitrosourea (MNH) following the procedure of Satoh and Omura. The panicles of rice variety 'IR22' were soaked in 1 mM MNH solution for 45 minutes at 16 to 18 hours after flowering. Two thousand six hundred and forty fertile M 1 plants were produced. From these plants M 2 lines with 10 or more seedlings were planted in the field to evaluate their reaction against tungro under natural conditions in the 1990 dry season on the IRRI central research farm, Los Banos, the Philippines. Of these, 124 M 2 lines were selected by visual evaluation. Five plants were harvested individually from each selected line. A bulk was also made from all the remaining plants in the line. In the M 3 generation, each family consisted of five sister lines and one bulked line. One line (M 3 -723) showed no tungro symptoms and its related bulk segregated for resistance but all other M 3 lines from the same family were susceptible to tungro. The resistant line, M 3 -723, showed low infection with RTBV and RTSV when leaves were tested by enzyme-linked immunosorbent assay (ELISA) to diagnose tungro infection. All M 4 lines from M 3 -723 showed uniform resistance in the field. They were not infected with RTBV and were resistant to RTSV infection

  8. Impurity induced resistivity upturns in underdoped cuprates

    Energy Technology Data Exchange (ETDEWEB)

    Das, Nabyendu, E-mail: nabyendudas@gmail.com; Singh, Navinder

    2016-01-28

    Impurity induced low temperature upturns in both the ab-plane and the c-axis dc-resistivities of cuprates in the pseudogap state have been observed in experiments. We provide an explanation of this phenomenon by incorporating impurity scattering of the charge carriers within a phenomenological model proposed by Yang, Rice and Zhang. The scattering between charge carriers and the impurity atom is considered within the lowest order Born approximation. Resistivity is calculated within Kubo formula using the impurity renormalized spectral functions. Using physical parameters for cuprates, we describe qualitative features of the upturn phenomena and its doping evolution that coincides with the experimental findings. We stress that this effect is largely due to the strong electronic correlations.

  9. Impurity induced resistivity upturns in underdoped cuprates

    International Nuclear Information System (INIS)

    Das, Nabyendu; Singh, Navinder

    2016-01-01

    Impurity induced low temperature upturns in both the ab-plane and the c-axis dc-resistivities of cuprates in the pseudogap state have been observed in experiments. We provide an explanation of this phenomenon by incorporating impurity scattering of the charge carriers within a phenomenological model proposed by Yang, Rice and Zhang. The scattering between charge carriers and the impurity atom is considered within the lowest order Born approximation. Resistivity is calculated within Kubo formula using the impurity renormalized spectral functions. Using physical parameters for cuprates, we describe qualitative features of the upturn phenomena and its doping evolution that coincides with the experimental findings. We stress that this effect is largely due to the strong electronic correlations.

  10. Bacterial Gibberellins Induce Systemic Resistance of Plants

    Directory of Open Access Journals (Sweden)

    I. N. FEKLISTOVA

    2014-06-01

    Full Text Available It is generally agreed today that some rhizosphere bacteria can ensure induced systemic resistance to pathogens. In this paper we tested the ability of gibberellins produced by rhizosphere non-pathogenic bacteria Pseudomonas aurantiaca to induce systemic resistance to alternariosis agent – Alternaria brassicicola – in oilseed rape plants.Oilseed rape (Brássica nápus is one of the most promising oil-bearing croppers. It allows improving the supply of population with vegetable oil, animal and poultry industries with high quality vegetable protein. It is used for biofuel production as well.Gibberellin preparation was isolated from liquid culture of strain Pseudomonas aurantiaca grown in 250 mL of M9 medium (48 h, 28 °C under darkroom conditions. Gibberellins were extracted according procedure described by Tien et al. (1979. Gibberellins concentration in the medium was determined by fluorometric method.Elicitor activity of bacterial metabolites – gibberellins – was analyzed in model system of artificial inoculation of oilseed rape germs with phytopathogenic fungi Alternaria brassicicola. The elicitor action efficiency was evaluated on the 15th day of oilseed rape cultivation based on the percentage of leaf surface covered by necrotic lesions.Gibberellins were shown to induce systemic resistance resulted in decreasing of oil seed plants   vulnerability by 52.7%.It is known that under the unfavorable conditions plants synthesis the reactive oxygen intermediates   which activate destructive processes. One of the first organism reactions to stress action is the change of the lipid peroxidation level. It was shown that treatment of the soil with gibberellins resulted in decreasing of the lipid peroxidation level twofold.Gibberellins were shown to have a similar effect on permeability of cell membranes for free nucleotides. The permeability of cell membranes in leaves decreased 2.8-fold at room temperature. We suggest that gibberellins

  11. Additive effect of rikkunshito, an herbal medicine, on chemotherapy-induced nausea, vomiting, and anorexia in uterine cervical or corpus cancer patients treated with cisplatin and paclitaxel: results of a randomized phase II study (JORTC KMP-02).

    Science.gov (United States)

    Ohnishi, Shunsuke; Watari, Hidemichi; Kanno, Maki; Ohba, Yoko; Takeuchi, Satoshi; Miyaji, Tempei; Oyamada, Shunsuke; Nomura, Eiji; Kato, Hidenori; Sugiyama, Toru; Asaka, Masahiro; Sakuragi, Noriaki; Yamaguchi, Takuhiro; Uezono, Yasuhito; Iwase, Satoru

    2017-09-01

    Rikkunshito, an herbal medicine, is widely prescribed in Japan for the treatment of anorexia and functional dyspepsia, and has been reported to recover reductions in food intake caused by cisplatin. We investigated whether rikkunshito could improve chemotherapy-induced nausea and vomiting (CINV) and anorexia in patients treated with cisplatin. Patients with uterine cervical or corpus cancer who were to receive cisplatin (50 mg/m² day 1) and paclitaxel (135 mg/m² day 0) as first-line chemotherapy were randomly assigned to the rikkunshito group receiving oral administration on days 0-13 with standard antiemetics, or the control group receiving antiemetics only. The primary endpoint was the rate of complete control (CC: no emesis, no rescue medication, and no significant nausea) in the overall phase (0-120 hours). Two-tailed panorexia. Copyright © 2017. Asian Society of Gynecologic Oncology, Korean Society of Gynecologic Oncology

  12. Effect of a thiolated polymer on oral paclitaxel absorption and tumor growth in rats.

    Science.gov (United States)

    Föger, Florian; Malaivijitnond, Suchinda; Wannaprasert, Thanakul; Huck, Christian; Bernkop-Schnürch, Andreas; Werle, Martin

    2008-02-01

    The anticancer agent paclitaxel is currently commercially available only as an infusion due to its low oral bioavailability. An oral formulation would be highly beneficial for patients. Besides the low solubility, the main reason for the limited oral bioavailability of paclitaxel is that it is a substrate of the efflux pump P-glycoprotein (P-gp). Recently, it has been demonstrated that P-gp can be inhibited by thiolated polymers. In this study, an oral paclitaxel formulation based on thiolated polycarbophil was evaluated in vivo in wild-type rats and in mammary cancer-induced rats. The paclitaxel plasma level after a single administration of paclitaxel was observed for 12 h in healthy rats. Moreover, cancer-induced rats were treated weekly for 5 weeks with the novel formulation. It was demonstrated that (1) co-administration of thiolated polycarbophil significantly improved paclitaxel plasma levels, (2) a more constant pharmacokinetic profile could be achieved and (3) the tumor growth was reduced. These effects can most likely be attributed to P-gp inhibition. According to the achieved results, thiolated polymers are believed to be interesting tools for the delivery of P-gp substrates such as paclitaxel.

  13. FoxO3a transcriptional regulation of Bim controls apoptosis in paclitaxel-treated breast cancer cell lines

    NARCIS (Netherlands)

    Sunters, A.; Fernandez de Mattos, S.; Stahl, M.; Brosens, J.J.; Zoumpoulidou, G.; Saunders, C.A.; Coffer, P.J.; Medema, R.H.; Coombes, R.C.; Lam, E.W.-F.

    2003-01-01

    Paclitaxel is used to treat breast cancers, but the mechanisms by which it induces apoptosis are poorly understood. Consequently, we have studied the role of the FoxO transcription factors in determining cellular response to paclitaxel. Western blotting revealed that in a panel of nine breast cancer

  14. FoxO3a transcriptional regulation of bim controls apoptosis in paclitaxel-treated breast cancer cell lines

    NARCIS (Netherlands)

    Sunters, A; de Mattos, SF; Stahl, M; Brosens, JJ; Zoumpoulidou, G; Saunders, CA; Coffer, PJ; Medema, RH; Coombes, RC; Lam, EWF

    2003-01-01

    Paclitaxel is used to treat breast cancers, but the mechanisms by which it induces apoptosis are poorly understood. Consequently, we have studied the role of the FoxO transcription factors in determining cellular response to paclitaxel. Western blotting revealed that in a panel of nine breast cancer

  15. Induced mutations for soybean rust resistance

    International Nuclear Information System (INIS)

    Smutkupt, S.; Wongpiyasatid, A.; Lamseejan, S.

    1983-01-01

    Soybean mutation experiments for inducing rust resistance in the cultivars G 8375, Wakashima mutant number 10, Taichung N, S.J.2, S.J.4, BM 50, BM 98, G 8377, G 8586 and G 8587 have been carried out since 1979. Six pods from each of 4438 control and 43,907 M 1 plants were randomly harvested. M 2 seeds of each cultivar of different doses were bulked (M 2 bulk). In addition, 270 good M 1 plants were selected and threshed singly (M 2 single). M 2 -bulk and M 2 -single seeds were advanced to M 3 . Both, M 3 -bulk and M 3 -single plants, together with the remaining M 2 -bulk seeds were screened for rust resistance in the rainy season of 1980 in Nong Hoi Valley (altitude about 1000 m above sea level) and at Mae Joe Station, both in Chiang Mai Province (latitude 18 deg. 31'-19 deg. N). Based on the IWGSR rating system, soybean plants with slow growth of rust were selected from both locations. The results were as follows: Six plants were selected from a total of 2802 control plants, and 115 from a total of 28,834 M 2 and M 3 plants. Further evaluation of these selections for rust resistance will be carried out in the rainy season of 1981 in Nong Hoi Valley, Chiang Mai. (author)

  16. Design, Synthesis and Applications of Hyaluronic Acid-Paclitaxel Bioconjugatesâ€

    Directory of Open Access Journals (Sweden)

    Rinaldo Marini Bettolo

    2008-02-01

    Full Text Available Paclitaxel (1a, a well known antitumor agent adopted mainly for the treatmentof breast and ovarian cancer, suffers from significant disadvantages such as low solubility,certain toxicity and specific drug-resistance of some tumor cells. To overcome theseproblems extensive research has been carried out. Among the various proposed strategies,the conjugation of paclitaxel (1a to a biocompatible polymer, such as hyaluronic acid(HA, 2, has also been considered. Coupling a bioactive compound to a biocompatiblepolymer offers, in general, many advantages such as better drug solubilization, betterstabilization, specific localization and controlled release. Hereafter the design, synthesisand applications of hyaluronic acid-paclitaxel bioconjugates are reviewed. An overview ofHA-paclitaxel combinations is also given.

  17. The battle of "nano" paclitaxel

    NARCIS (Netherlands)

    Sofias, Alexandros Marios; Dunne, Michael; Storm, Gert; Allen, Christine

    2017-01-01

    Paclitaxel (PTX) is one of the three most widely used chemotherapeutic agents, together with doxorubicin and cisplatin, and is first or second line treatment for several types of cancers. In 2000, Taxol, the conventional formulation of PTX, became the best-selling cancer drug of all time with annual

  18. Acibenzolar-S-methyl induces lettuce resistance against ...

    African Journals Online (AJOL)

    ... contributing to the enhancement of plant resistance. The effect was comparable with copper treatment. As a marker of resistance, PR protein activity chitinase showed remarkable increase, depending on decreasing bacterial growth in planta. Key words: Acibenzolar-S-methyl, induced resistance, Xanthomonas campestris ...

  19. Clopidogrel paclitaxel drug-drug interaction

    DEFF Research Database (Denmark)

    Agergaard, K; Mau-Sørensen, M; Stage, T B

    2017-01-01

    register. Peripheral sensory neuropathy was retrospectively evaluated from medical charts and compared to that of 88 age and sex matched controls treated with paclitaxel and low dose aspirin. By a cumulative dose of 1500 mg paclitaxel, 35% of the patients had developed severe neuropathy. The overall hazard...... ratio between clopidogrel use and severe paclitaxel neuropathy was 1.7 (95% CI, 0.9-3.0). Among those receiving a high dose paclitaxel regimen, the hazard ratio was 2.3 (95% CI, 1.1-4.5). Our study indicates that clopidogrel is associated with a clinically relevant increased risk of neuropathy......Paclitaxel is mainly eliminated by CYP2C8 in the liver. CYP2C8 is strongly inhibited by the clopidogrel metabolite acyl-β-D-glucuronide. To determine if this interaction has clinical relevance, we identified 48 patients treated with clopidogrel and paclitaxel using databases and a prescription...

  20. Dragon (RGMb) induces oxaliplatin resistance in colon cancer cells.

    Science.gov (United States)

    Shi, Ying; Huang, Xiao-Xiao; Chen, Guo-Bin; Wang, Ying; Zhi, Qiang; Liu, Yuan-Sheng; Wu, Xiao-Ling; Wang, Li-Fen; Yang, Bing; Xiao, Chuan-Xing; Xing, Hui-Qin; Ren, Jian-Lin; Xia, Yin; Guleng, Bayasi

    2016-07-26

    Colorectal cancer (CRC) is one of the most commonly diagnosed cancers and a major cause of cancer mortality. Chemotherapy resistance remains a major challenge for treating advanced CRC. Therefore, the identification of targets that induce drug resistance is a priority for the development of novel agents to overcome resistance. Dragon (also known as RGMb) is a member of the repulsive guidance molecule (RGM) family. We previously showed that Dragon expression increases with CRC progression in human patients. In the present study, we found that Dragon inhibited apoptosis and increased viability of CMT93 and HCT116 cells in the presence of oxaliplatin. Dragon induced resistance of xenograft tumor to oxaliplatinin treatment in mice. Mechanistically, Dragon inhibited oxaliplatin-induced JNK and p38 MAPK activation, and caspase-3 and PARP cleavages. Our results indicate that Dragon may be a novel target that induces drug resistance in CRC.

  1. Induced mutation for disease resistance in legumes

    International Nuclear Information System (INIS)

    Bravo, A.

    1984-01-01

    Mutation breeding has been used for developing genotypes that may contain resistance to: a) A necrotic strain of common mosaic virus, in common bean (Phaseolus vulgaris L.); b) Soil fungi causing root rots in chickpea (Cicer arietinum L.); c) The fungus Uromyces fabae that causes rust in lentil plants (Lens culinaria). Seeds of these three species were treated with gamma rays in doses of 1,000, 3,000, 6,000, and 9,000 rads. Treated materials and controls were grown during 1979. Chickpea M2 plants were grown in a naturally infested soil with soil-borne fungi. Lentil plants were sprayed with a suspension of spores of the rust fungus. Common bean M2 plants were sprayed with a solution containing virus particles. Ninety-three symptomless chickpea plants were identified in the M2 population. For lentil there were 47 symptomless plants and for common bean, 244 M2 plants with minor virus damage. Eight M3 progenies of chickpea, originated from symptomless M2 plants, had a high rate of survival and showed none or very little damage by root rots. In addition, some morphological changes were detected in other M3 chickpea progenies. Two progenies had larger leaflets, as compared to the control plants and those of other progenies. One progeny showed a more erect growth habit. These new traits have been attributed to genetic changes induced by the radiation treatments. By contrast to these promising results with chickpea no progress has been detected in the plant populations of common bean and lentil. (author)

  2. Induced multiple disease resistance in wheat

    International Nuclear Information System (INIS)

    Borojevic, K.; Worland, A.J.

    1990-01-01

    Full text: The existence of genes suppressing resistance to leaf rust, stem rust and yellow rust in hexaploid wheat has been suggested. If such genes are deleted or inactivated, a more resistant variety may be obtained. In mutant lines of the wheat variety San Pastore, selected after treatment with 20,000 rad of gamma-rays, resistance to leaf rust, yellow rust, stem rust, and to some extent to Erysiphe graminis was determined. The mutants responded to infection by producing necrotic flecks in the presence of high level of disease inoculum. Similar flecks develop under stress condition. It is likely that the mother variety San Pastore carries genes for resistance which are masked by suppressor genes. Irradiation inactivates suppressors so that resistance genes which were previously masked are expressed. The first results of monosomic analysis indicate that chromosomes of groups 4 and 5 or possibly 7 may be critical for expression of resistance in the mutant lines. (author)

  3. Cytotoxicity and cell-cycle effects of paclitaxel when used as a single agent and in combination with ionizing radiation

    International Nuclear Information System (INIS)

    Gupta, Nalin; Hu, Lily J.; Deen, Dennis F.

    1997-01-01

    Purpose: This study aimed to determine the extent of paclitaxel-induced cytotoxicity and cell-cycle perturbations when used alone and in combination with radiation in human glioma cells. Methods and Materials: The effect of paclitaxel alone on three human glioma cells lines--SF-126, U-87 MG, and U-251 MG--was assessed after 24, 48, 72, or 96 h treatment. For experiments in combination with radiation, cells were exposed to either a long (48-h) or short (8-h) duration of paclitaxel treatment prior to irradiation. Cell survival was determined by clonogenic assay. Cell cycle perturbations were assessed by using flow cytometry to measure the proportion of cells in G 1 , S, and G 2 /M phases. Results: When cells were treated with paclitaxel alone for ≥24 h, cytotoxicity increased up to a threshold dose, after which it plateaued. When treatment duration was ≤24 h, cytotoxicity was appreciably greater in U-251 MG cells than in SF-126 and U-87 MG cells. After 24 h of paclitaxel treatment, cells in plateau phase growth had increased survival compared to cells in log phase growth. In contrast, after 8 h paclitaxel treatment, mitotic cells had reduced survival compared to cells from an asynchronous population. Cell-cycle perturbations were consistent with the presence of a mitotic block after paclitaxel treatment, although changes in other cell-cycle phase fractions varied among cell lines. For experiments in combination with radiation, cytotoxicity was increased when cells were irradiated after 48 h of paclitaxel treatment but not after 8 h of treatment. Conclusion: The duration of paclitaxel treatment and the location of cells in the cell cycle modify the degree of radiation cytotoxicity. The mechanisms of paclitaxel cytotoxicity are likely to be multifactorial because varying effects are seen in different cell lines. Furthermore, it is clear that simply increasing the number of cells in G 2 /M is insufficient in itself to increase the response of cells to radiation

  4. PEDF-induced alteration of metabolism leading to insulin resistance.

    Science.gov (United States)

    Carnagarin, Revathy; Dharmarajan, Arunasalam M; Dass, Crispin R

    2015-02-05

    Pigment epithelium-derived factor (PEDF) is an anti-angiogenic, immunomodulatory, and neurotrophic serine protease inhibitor protein. PEDF is evolving as a novel metabolic regulatory protein that plays a causal role in insulin resistance. Insulin resistance is the central pathogenesis of metabolic disorders such as obesity, type 2 diabetes mellitus, polycystic ovarian disease, and metabolic syndrome, and PEDF is associated with them. The current evidence suggests that PEDF administration to animals induces insulin resistance, whereas neutralisation improves insulin sensitivity. Inflammation, lipolytic free fatty acid mobilisation, and mitochondrial dysfunction are the proposed mechanism of PEDF-mediated insulin resistance. This review summarises the probable mechanisms adopted by PEDF to induce insulin resistance, and identifies PEDF as a potential therapeutic target in ameliorating insulin resistance. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  5. Induced resistance and gene expression in wheat against leaf rust ...

    African Journals Online (AJOL)

    uvp

    2013-05-15

    May 15, 2013 ... 2Department of Soil, Crop and Climate Sciences, University of the Free State, P.O Box ... Key words: Wheat leaf rust, induced resistance, priming, gene ..... transformation: susceptibility of transgenic Nicotiana sylvestris plants.

  6. nitrosoguanidine-induced cadmium resistant mutants of Aspergillus

    Indian Academy of Sciences (India)

    Unknown

    nitrosoguanidine-induced cadmium resistant mutants of. Aspergillus niger. SAMAR ... gens and UV irradiation to study transportation of cad- mium ion through cell ..... Rowley W S 1993 Yeast bZib proteins mediate pleiotropic drug and metal ...

  7. Xylitol prevents NEFA-induced insulin resistance in rats

    Science.gov (United States)

    Kishore, P.; Kehlenbrink, S.; Hu, M.; Zhang, K.; Gutierrez-Juarez, R.; Koppaka, S.; El-Maghrabi, M. R.

    2013-01-01

    Aims/hypothesis Increased NEFA levels, characteristic of type 2 diabetes mellitus, contribute to skeletal muscle insulin resistance. While NEFA-induced insulin resistance was formerly attributed to decreased glycolysis, it is likely that glucose transport is the rate-limiting defect. Recently, the plant-derived sugar alcohol xylitol has been shown to have favourable metabolic effects in various animal models. Furthermore, its derivative xylulose 5-phosphate may prevent NEFA-induced suppression of glycolysis. We therefore examined whether and how xylitol might prevent NEFA-induced insulin resistance. Methods We examined the ability of xylitol to prevent NEFA-induced insulin resistance. Sustained ~1.5-fold elevations in NEFA levels were induced with Intralipid/heparin infusions during 5 h euglycaemic–hyperinsulinaemic clamp studies in 24 conscious non-diabetic Sprague-Dawley rats, with or without infusion of xylitol. Results Intralipid infusion reduced peripheral glucose uptake by ~25%, predominantly through suppression of glycogen synthesis. Co-infusion of xylitol prevented the NEFA-induced decreases in both glucose uptake and glycogen synthesis. Although glycolysis was increased by xylitol infusion alone, there was minimal NEFA-induced suppression of glycolysis, which was not affected by co-infusion of xylitol. Conclusions/interpretation We conclude that xylitol prevented NEFA-induced insulin resistance, with favourable effects on glycogen synthesis accompanying the improved insulin-mediated glucose uptake. This suggests that this pentose sweetener has beneficial insulin-sensitising effects. PMID:22460760

  8. Insulin Resistance Induced by Short term Fructose Feeding may not ...

    African Journals Online (AJOL)

    Fructose feeding causes insulin resistance and invariably Non-Insulin Dependent Diabetes Mellitus (NIDDM) in rats and genetically predisposed humans. The effect of insulin resistance induced by short term fructose feeding on fertility in female rats was investigated using the following parameters: oestrous phase and ...

  9. Latitudinal Gradients in Induced and Constitutive Resistance against Herbivores.

    Science.gov (United States)

    Anstett, Daniel N; Chen, Wen; Johnson, Marc T J

    2016-08-01

    Plants are hypothesized to evolve increased defense against herbivores at lower latitudes, but an increasing number of studies report evidence that contradicts this hypothesis. Few studies have examined the evolution of constitutive and induced resistance along latitudinal gradients. When induction is not considered, underlying patterns of latitudinal clines in resistance can be obscured because plant resistance represents a combination of induced and constitutive resistance, which may show contrasting patterns with latitude. Here, we asked if there are latitudinal gradients in constitutive versus induced resistance by using genotypes of Oenothera biennis (Onagraceae) sampled along an 18° latitudinal gradient. We conducted two bioassay experiments to compare the resistance of plant genotypes against one generalist (Spodoptera exigua) and one specialist (Acanthoscelidius acephalus) herbivore. These insects were assayed on: i) undamaged control plants, ii) plants that had been induced with jasmonic acid, and iii) plants induced with herbivore damage. Additionally, we examined latitudinal gradients of constitutive and induced chemical resistance by measuring the concentrations of total phenolics, the concentration of oxidized phenolics, and the percentage of phenolics that were oxidized. Spodoptera exigua showed lower performance on plants from lower latitudes, whereas A. acephalus showed no latitudinal pattern. Constitutive total phenolics were greater in plants from lower latitudes, but induced plants showed higher total phenolics at higher latitudes. Oxidative activity was greatest at higher latitudes regardless of induction. Overall, both latitude and induction have an impact on different metrics of plant resistance to herbivory. Further studies should consider the effect of induction and herbivore specialization more explicitly, which may help to resolve the controversy in latitudinal gradients in herbivory and defense.

  10. Induced mutations for disease resistance in wheat

    International Nuclear Information System (INIS)

    Cerny, J.; Hanis, M.; Hanisova, A.; Knytl, V.; Sasek, A.

    1983-01-01

    Mutation induction has been used over a period of 20 years to obtain mutants of wheat with improved disease resistance. 34 wheat cultivars have been treated with X-rays, gamma rays, thermal neutrons or EMS. A great number of mutants were selected. Their mutational origin was verified by electrophoretic analysis of gliadin spectra. Resistances have been confirmed over several generations. None of the mutants have been released yet for commercial cultivation because of shortcomings in yield or susceptibility to other diseases. The use of mutants in cross-breeding is considered. (author)

  11. The Urtica dioica extract enhances sensitivity of paclitaxel drug to MDA-MB-468 breast cancer cells.

    Science.gov (United States)

    Mohammadi, Ali; Mansoori, Behzad; Aghapour, Mahyar; Shirjang, Solmaz; Nami, Sanam; Baradaran, Behzad

    2016-10-01

    Due to the chemo resistant nature of cancer cells and adverse effects of current therapies, researchers are looking for the most efficient therapeutic approach which has the lowest side effects and the highest toxicity on cancer cells. The aim of the present study was to investigate the synergic effect of Urtica dioica extract in combination with paclitaxel on cell death and invasion of human breast cancer MDA-MB-468 cell line. To determine the cytotoxic effects of Urtica dioica extract with paclitaxel, MTT assay was performed. The scratch test was exploited to assess the effects of Urtica dioica, Paclitaxel alone and combination on migration of cancer cells. The expression levels of snail-1, ZEB1, ZEB2, twist, Cdc2, cyclin B1 and Wee1 genes were quantified using qRT-PCR and western blot performed for snail-1expression. The effects of plant extract, Paclitaxel alone and combination on different phases of cell cycle was analyzed using flow cytometry. Results of MTT assay showed that Urtica dioica significantly destroyed cancer cells. Interestingly, Concurrent use of Urtica dioica extract with paclitaxel resulted in decreased IC50 dose of paclitaxel. Moreover, findings of scratch assay exhibited the inhibitory effects of Urtica dioica, Paclitaxel alone and combination on migration of MDA-MB-468 cell line. Our findings also demonstrated that the extract substantially decreased the Snail-1 and related gene expression. Ultimately, Cell cycle arrest occurred at G2/M phase post-treatment by deregulating Cdc2 and wee1. Our results demonstrated that the dichloromethane extract of Urtica dioica inhibit cell growth and migration. Also, Urtica dioica extract substantially increased sensitivity of breast cancer cells to paclitaxel. Therefore, it can be used as a potential candidate for treatment of breast cancer with paclitaxel. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  12. Insulin resistance induced by antiretroviral drugs: Current ...

    African Journals Online (AJOL)

    Treatment with highly active antiretroviral therapy (HAART) has improved the prognosis of patients with AIDS, but it has also increased the incidence of various metabolic disorders, in particular insulin resistance accompanied by dyslipidaemia, hyperglycaemia and lipodystrophy. This is often accompanied by frank type 2 ...

  13. Nanoparticle Albumin-Bound-Paclitaxel in the Treatment of Metastatic Urethral Adenocarcinoma: The Significance of Molecular Profiling and Targeted Therapy

    Directory of Open Access Journals (Sweden)

    Yasmin M. Abaza

    2014-01-01

    Full Text Available Primary urethral cancer is rare and accounts for only 0.003% of all malignancies arising from the female genitourinary tract. Due to the rarity of this disease, no consensus exists regarding the optimal therapeutic approach. Nanoparticle albumin-bound-paclitaxel has been shown to be effective in the treatment of a number of malignancies including metastatic breast, pancreatic, and bladder cancer. We present a 67-year-old woman with advanced metastatic urethral adenocarcinoma resistant to two lines of chemotherapy (ifosfamide/paclitaxel/cisplatin and irinotecan/5-fluorouracil/leucovorin that showed a dramatic response to nanoparticle albumin-bound-paclitaxel. This is the first case report to document the use and efficacy of nanoparticle albumin-bound-paclitaxel in the treatment of unresectable metastatic urethral cancer.

  14. Induced lodging resistance in upland rice

    International Nuclear Information System (INIS)

    Arumugam Pillai, M.; Subramanian, M.

    1990-01-01

    Full text: Seeds of two short duration but tall upland rice varieties ''PMK 1'' and ''Poongar'', susceptible to lodging, were subjected to mutation breeding in 1988-1989. Dry seeds of these two varieties were treated with 20, 25 and 30 krad of gamma rays and soaked seeds were treated with 40, 50 and 60 mM concentration of EMS. In M 2 generation lodging was measured and a correlation study was made between the angle of lodging and various characters like plant height, length of lower internode, productive tiller number, culm diameter and panicle weight. The angle to which the main tiller can be bent before lodging on the 25th day after flowering was measured by using a protractor. Those plants which lodged at an angle beyond 30 deg. from the vertical plane were classified as lodging. From 60,000 M 2 plants, 78 lodging resistant semi-dwarf mutants and 5 dwarf mutants were selected. As expected, there was generally a negative correlation between internode length and lodging resistance and a positive correlation of culm diameter with lodging resistance. For plant height and tiller numbers, correlations were not so clear. (author)

  15. The battle of "nano" paclitaxel.

    Science.gov (United States)

    Sofias, Alexandros Marios; Dunne, Michael; Storm, Gert; Allen, Christine

    2017-12-01

    Paclitaxel (PTX) is one of the three most widely used chemotherapeutic agents, together with doxorubicin and cisplatin, and is first or second line treatment for several types of cancers. In 2000, Taxol, the conventional formulation of PTX, became the best-selling cancer drug of all time with annual sales of 1.6 billion. In 2005, the introduction of the albumin-based formulation of PTX, known as Abraxane, ended Taxol's monopoly of the PTX market. Abraxane's ability to push the Taxol innovator and generic formulations aside attracted fierce competition amongst competitors worldwide to develop their own unique, new and improved formulation of PTX. At this time there are at least 18 companies focused on pre-clinical and/or clinical development of nano-formulations of PTX. These pharmaceutical companies are investing substantial capital to capture a share of the lucrative global PTX market. It is hoped that any formulation that dominates the market will result in tangible benefits to patients in terms of both survival and quality of life. Given all of this activity, here we address the question: Who is going to win the battle of "nano" paclitaxel? Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Optimizing anticancer drug treatment in pregnant cancer patients : pharmacokinetic analysis of gestation-induced changes for doxorubicin, epirubicin, docetaxel and paclitaxel

    NARCIS (Netherlands)

    van Hasselt, J G C; van Calsteren, K; Heyns, L; Han, S; Mhallem Gziri, M; Schellens, J H M; Beijnen, J H; Huitema, A D R; Amant, F

    2014-01-01

    BACKGROUND: Pregnant patients with cancer are increasingly treated with anticancer drugs, although the specific impact of pregnancy-induced physiological changes on the pharmacokinetics (PK) of anticancer drugs and associated implications for optimal dose regimens remains unclear. Our objectives

  17. Concurrent paclitaxel and radiotherapy. Treatment feasibility studies

    International Nuclear Information System (INIS)

    Vogt, H.G.; Martin, T.; Kolotas, C.; Hey, S.; Schneider, L.; Templin, T.; Zamboglou, N.; Dornoff, W.; Kettner, H.

    1997-01-01

    Background: The anti-neoplastic effect of paclitaxel has been demonstrated in various clinical studies in different malignant diseases. Clinical studies have also demonstrated a greater efficacy for simultaneous radio-chemotherapy compared with radiotherapy alone when using radiosensitizing drugs. Based on these clinical and in-vitro data we initiated several pilot studies using paclitaxel as a radiosensitizing agent and we now present our initial experience in its use in a combined modality protocol, radiation and simultaneous chemotherapy with paclitaxel. Methods: I. Concurrent paclitaxel and radiation for locally advanced non-small-cell lung cancer (NSCLC): In a phase-I-study we applicated paclitaxel (45 to 65 mg/m 2 ) as a 3-hour infusion weekly for 3 to 7 weeks simultaneously with primary radiotherapy in shrinking field technique with 5x1.8 Gy/week up to 59.4 Gy. - II. Concurrent paclitaxel and radiation for breast cancer as neoadjuvant or palliative: 50 mg/m 2 paclitaxel as a 3-hour infusion weekly for 6 weeks simultaneous with neoadjuvant or palliative radiotherapy of the breast/chest wall with 5x1.8 Gy/week up to 54.0 Gy. - III./IV. Concurrent paclitaxel/carboplatin and combined radiation (EBRT+brachytherapy) for locally advanced inoperable cancer of the cervix: 50 mg/m 2 paclitaxel as a 3-hour infusion weekly for 5 weeks, 50 mg/m 2 carboplatin at day 1 to 5 in week 1 and 5 simultaneously with external beam radiotherapy of the pelvis with 5x1.8 Gy/week up to 54.0 Gy and endocavitary LDR-brachytherapy (4x5 Gy). - V. Concurrent paclitaxel and radiation for locally advanced inoperable cancer of the bladder: 50 mg/m 2 paclitaxel as a 3-hour infusion weekly for 5 weeks simultaneous with radiotherapy of the pelvis with 5x1.8 Gy/week up to 50.4 Gy. VI. Concurrent paclitaxel and radiation in locally advanced inoperable head and neck cancer: 50 mg/m 2 paclitaxel as a 3-hour infusion weekly for 7 to 8 weeks simultaneous with radiotherapy in shrinking field technique

  18. Paclitaxel Albumin-stabilized Nanoparticle Formulation

    Science.gov (United States)

    This page contains brief information about paclitaxel albumin-stabilized nanoparticle formulation and a collection of links to more information about the use of this drug, research results, and ongoing clinical trials.

  19. Regorafenib overcomes chemotherapeutic multidrug resistance mediated by ABCB1 transporter in colorectal cancer: In vitro and in vivo study.

    Science.gov (United States)

    Wang, Yi-Jun; Zhang, Yun-Kai; Zhang, Guan-Nan; Al Rihani, Sweilem B; Wei, Meng-Ning; Gupta, Pranav; Zhang, Xiao-Yu; Shukla, Suneet; Ambudkar, Suresh V; Kaddoumi, Amal; Shi, Zhi; Chen, Zhe-Sheng

    2017-06-28

    Chemotherapeutic multidrug resistance (MDR) is a significant challenge to overcome in clinic practice. Several mechanisms contribute to MDR, one of which is the augmented drug efflux induced by the upregulation of ABCB1 in cancer cells. Regorafenib, a multikinase inhibitor targeting the RAS/RAF/MEK/ERK pathway, was approved by the FDA to treat metastatic colorectal cancer and gastrointestinal stromal tumors. We investigated whether and how regorafenib overcame MDR mediated by ABCB1. The results showed that regorafenib reversed the ABCB1-mediated MDR and increased the accumulation of [ 3 H]-paclitaxel in ABCB1-overexpressing cells by suppressing efflux activity of ABCB1, but not altering expression level and localization of ABCB1. Regorafenib inhibited ATPase activity of ABCB1. In mice bearing resistant colorectal tumors, regorafenib raised the intratumoral concentration of paclitaxel and suppressed the growth of resistant colorectal tumors. But regorafenib did not induce cardiotoxicity/myelosuppression of paclitaxel in mice. Strategy to reposition one FDA-approved anticancer drug regorafenib to overcome the resistance of another FDA-approved, widely used chemotherapeutic paclitaxel, may be a promising direction for the field of adjuvant chemotherapy. This study provides clinical rationale for combination of conventional chemotherapy and targeted anticancer agents. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. The chemotherapeutic agent paclitaxel selectively impairs learning while sparing source memory and spatial memory.

    Science.gov (United States)

    Smith, Alexandra E; Slivicki, Richard A; Hohmann, Andrea G; Crystal, Jonathon D

    2017-03-01

    Chemotherapeutic agents are widely used to treat patients with systemic cancer. The efficacy of these therapies is undermined by their adverse side-effect profiles such as cognitive deficits that have a negative impact on the quality of life of cancer survivors. Cognitive side effects occur across a variety of domains, including memory, executive function, and processing speed. Such impairments are exacerbated under cognitive challenges and a subgroup of patients experience long-term impairments. Episodic memory in rats can be examined using a source memory task. In the current study, rats received paclitaxel, a taxane-derived chemotherapeutic agent, and learning and memory functioning was examined using the source memory task. Treatment with paclitaxel did not impair spatial and episodic memory, and paclitaxel treated rats were not more susceptible to cognitive challenges. Under conditions in which memory was not impaired, paclitaxel treatment impaired learning of new rules, documenting a decreased sensitivity to changes in experimental contingencies. These findings provide new information on the nature of cancer chemotherapy-induced cognitive impairments, particularly regarding the incongruent vulnerability of episodic memory and new learning following treatment with paclitaxel. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Oxygen-carbon nanotubes as a chemotherapy sensitizer for paclitaxel in breast cancer treatment.

    Directory of Open Access Journals (Sweden)

    Yongkun Wang

    Full Text Available To study the in vivo and in vitro effects of adding oxygen carbon nanotubes (CNTs to chemotherapy for breast cancer.MCF-7 and SK-BR-3 breast cancer cells were co-cultured with paclitaxel and then exposed to oxygen-CNTs under hypoxic conditions. Cell proliferation, viability, and apoptosis rate were analyzed. Hypoxia-inducible factor-1 alpha (HIF-1α expression was measured using reverse transcription-polymerase chain reaction (RT-PCR and western blot. Nude mice were used as a human breast cancer model to explore the impact of oxygen-CNTs on the in vivo chemotherapeutic effect of paclitaxel.Oxygen-CNTs had no significant effects on the growth of breast cancer cells under normoxia and hypoxia. However, in the hypoxic environment, oxygen-CNTs significantly enhanced the inhibitory effect of paclitaxel on cell proliferation, as well as the apoptosis rate. Under hypoxia, downregulation of HIF-1α and upregulation of caspase-3, caspase-8, caspase-9, LC3 and Beclin-1 were observed when paclitaxel was combined with oxygen-CNT. Furthermore, addition of oxygen-CNTs to chemotherapy was found to significantly reduce tumor weight in the tumor-bearing mice model.Oxygen-CNTs can significantly increase the chemotherapeutic effect of paclitaxel on breast cancer cells. Oxygen-CNTs may be a potential chemosensitizer in breast cancer therapy.

  2. Role of riboflavin and thiamine in induced resistance against ...

    African Journals Online (AJOL)

    The effect of two inducer chemicals, that is, riboflavin (B2) and thiamine (B1) on the induction of systemic resistance in soybean against charcoal rot disease as well as biochemical changes associated with these treatments in soybean plants was investigated. Under greenhouse condition, the dose effect of 0.1 to 15 mM ...

  3. Induced mutations of rust resistance genes in wheat

    International Nuclear Information System (INIS)

    McIntosh, R.A.

    1983-01-01

    Induced mutations are being used as a tool to study genes for resistance in wheat. It was found that Pm1 can be separated from Lr20 and Sr15, but these two react like a single pleiotropic gene. Mutants were further examined in crosses and backmutations have been attempted. (author)

  4. Foliar application of systemic acquired resistance (SAR) inducers for ...

    African Journals Online (AJOL)

    nbuensanteai

    2013-08-14

    Aug 14, 2013 ... induced by chitosan and BTH were involved in defense mechanism, reflecting the strong direct positive effect that chitosan ... to control plant diseases based on the systemic acquired resistance ... salicylic acid (SA) as a signal molecule and is associated ... treated plants for SAR relating chemical analyses.

  5. Induced mutations for resistance to leaf rust in wheat

    International Nuclear Information System (INIS)

    Borojevic, K.

    1983-01-01

    Problems related to the induction of mutations for disease resistance were investigated under several aspects, using the wheat/leaf rust system. Previously selected mutant lines, tested in M 11 and M 13 , were found to differ with regard to infection type and disease severity from the original varieties. To verify the induced-mutation origin, these mutants were examined further using test crosses with carriers of known genes for leaf rust resistance and electrophoresis. A separate experiment to induce mutations for leaf rust resistance in the wheat varieties Sava, Aurora and Siete Cerros, using gamma rays, fast neutrons and EMS, yielded mutants with different disease reaction in the varieties Sava and Aurora at a frequency of about 1x10 - 3 per M 1 plant progenies. (author)

  6. Cross-resistance to radiation in human squamous cell carcinoma cells with induced cisplatin resistance

    International Nuclear Information System (INIS)

    Komori, Keiichi

    1998-01-01

    Accumulated evidence indicates that drug resistance is induced in tumor cells treated with a variety of anti-cancer drugs and that there is a possibility of cross-resistance to ionizing radiation associated with induced drug resistance. Most in vitro studies have shown inconsistent results on cross-resistance probably because of different cell lines used and protocols for drug induction. In this study, TE3 human squamous cell carcinoma cell line was treated with a 4-day cycle of cisplatin (cis-diamminedichloroplatinum (II); CDDP) at a concentration yielding 10% cell survival. The treatment was repeated up to 3 cycles. After treatment, cells were tested for CDDP and X-ray sensitivity. One cycle of CDDP treatment induced CDDP resistance with a factor of 1.41 and 2 cycles of the treatment with a factor of 1.86. The resistance factor reached a plateau at 3 cycles of treatment. For analyzing the correlation of CDDP and X-ray resistance, 30 clones from both untreated and 3-cycle treated cells were isolated and analyzed for CDDP and X-ray sensitivity. The sensitivity was expressed as the concentration of drug or dose of X-ray required to reduce the cell survival to x% (Dx). The correlation coefficient of clones with 3-cycle treatment between CDDP and X-ray sensitivity increased gradually by increasing the end point of Dx from D 10 to D 90 , resulting in significant correlation at D 90 . The result suggested that there is a certain common repair-related mechanism affecting both CDDP and X-ray resistance in CDDP-treated cells. (author)

  7. Flurbiprofen ameliorates glucose deprivation-induced leptin resistance

    Directory of Open Access Journals (Sweden)

    Toru Hosoi

    2016-09-01

    Full Text Available Leptin resistance is one of the mechanisms involved in the pathophysiology of obesity. The present study showed that glucose deprivation inhibited leptin-induced phosphorylation of signal transducer and activator of transcription 3 (STAT3 and signal transducer and activator of transcription 5 (STAT5 in neuronal cells. Flurbiprofen reversed glucose deprivation-mediated attenuation of STAT3, but not STAT5 activation, in leptin-treated cells. Glucose deprivation increased C/EBP-homologous protein (CHOP and glucose regulated protein 78 (GRP78 induction, indicating the activation of unfolded protein responses (UPR. Flurbiprofen did not affect the glucose deprivation-induced activation of UPR, but did attenuate the glucose deprivation-mediated induction of AMP-activated protein kinase (AMPK phosphorylation. Flurbiprofen may ameliorate glucose deprivation-induced leptin resistance in neuronal cells.

  8. Nanoparticle albumin-bound (nab-paclitaxel for the treatment of pancreas ductal adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Narayanan V

    2015-01-01

    Full Text Available Vignesh Narayanan,1 Colin D Weekes1,2 1Division of Medical Oncology, Department of Medicine, 2Developmental Therapeutics Program, University of Colorado Cancer Center, University of Colorado School of Medicine, Aurora, CO, USA Abstract: Pancreatic adenocarcinoma is a leading cause of cancer-related mortality worldwide, and surgical resection offers the only chance of cure. Since the majority of patients have unresectable disease at presentation, the emphasis has been on identifying effective chemotherapy regimens to prolong survival and control tumor burden. Gemcitabine has been the cornerstone of treatment ever since it was discovered to be an active agent in advanced pancreatic cancer nearly two decades ago, but the overall prognosis in patients with metastatic disease remains dismal. A dense fibrotic stroma around the tumor devoid of vasculature and the resultant hypoxic tumor microenvironment are implicated in the chemotherapy-resistant nature of this malignancy. In recent years, a growing body of literature has further elucidated several aspects of pancreatic tumor biology, such as its ability to utilize albumin from the peritumoral tissues to support its metabolic needs. High-pressure homogenization of paclitaxel with nanoparticle albumin results in the formation of soluble 130 nm complexes with albumin acting as the carrier for the otherwise hydrophobic paclitaxel. Once these complexes reach the tumor milieu, they act by depleting the tumor stroma. In addition, paclitaxel is also transported into the tumor cell along with albumin, where it then exerts its antineoplastic activity. Nanoparticle albumin-bound (nab-paclitaxel also increases gemcitabine levels inside the tumor cells by inhibiting cytidine deaminase, the enzyme that degrades gemcitabine. This review focuses on proposed mechanisms of efficacy of nab-paclitaxel in pancreatic cancer and discusses the preclinical and clinical studies of relevance. Keywords: pancreatic

  9. Resistance switching induced by electric fields in manganite thin films

    International Nuclear Information System (INIS)

    Villafuerte, M; Juarez, G; Duhalde, S; Golmar, F; Degreef, C L; Heluani, S P

    2007-01-01

    In this work, we investigate the polarity-dependent Electric Pulses Induced Resistive (EPIR) switching phenomenon in thin films driven by electric pulses. Thin films of 0.5 Ca 0.5 MnO 3 (manganite) were deposited by PLD on Si substrate. The transport properties at the interface between the film and metallic electrode are characterized in order to study the resistance switching. Sample thermal treatment and electrical field history are important to be considered for get reproducible EPIR effect. Carriers trapping at the interfaces are considered as a possible explanation of our results

  10. Treating methamphetamine-induced resistant psychosis with clozapine.

    Science.gov (United States)

    Seddigh, Ruohollah; Keshavarz-Akhlaghi, Amir-Abbas; Shariati, Behnam

    2014-01-01

    Background. Methamphetamine-induced psychosis (MIP) in Iran has turned into a serious issue in terms of health and treatment, lacking any obvious treatment methods for its resistant cases. Aims of Case Report. In the present study, a number of two cases of treatment of MIP with clozapine, which were resistant to the treatment with other antipsychotics, have been reported. Both cases completely responded to the treatment in only 2 weeks and no signs of psychosis relapse were seen in an 8-9 follow-up. Conclusion. Because of its particular pharmacologic features, clozapine may be effective in treating MIP.

  11. Paclitaxel and concurrent radiation for gastric cancer

    International Nuclear Information System (INIS)

    Safran, Howard; Wanebo, Harry J.; Hesketh, Paul J.; Akerman, Paul; Ianitti, David; Cioffi, William; Di Petrillo, Thomas; Wolf, Brian; Koness, James; McAnaw, Robert; Moore, Todd; Chen, M.-H.; Radie-Keane, Kathy

    2000-01-01

    Purpose: To determine the activity and toxicity of paclitaxel and concurrent radiation for gastric cancer. Methods and Materials: Twenty-seven patients were studied. Twenty-five had proximal gastric cancers, two had distal cancers. Eight had esophageal extension, 6 had celiac adenopathy, and 7 had retroperitoneal adenopathy. Patients received paclitaxel, 50 mg/m 2 by 3-hour intravenous (IV) infusion, weekly, on days 1, 8, 15, 22, and 29. Radiation was administered concurrently to a total dose of 45.0 Gy, in 1.80 Gy fractions, for 25 treatments. Patients who were medically or surgically inoperable received a sixth week of paclitaxel with a radiation boost to 50.4 Gy. Results: Esophagitis and gastritis were the most important toxicities, Grade 3 in four patients (15%), and Grade 4 in three patients (11%). Five patients (19%) had Grade 3 nausea. The overall response rate was 56%, including three patients (11%) with a complete response. The 2-year progression-free and overall survival rates were 29% and 31%, respectively. Conclusion: Concurrent paclitaxel and radiation demonstrates substantial local-regional activity in gastric cancer. Future investigations combining paclitaxel and radiation with other local-regional and systemic treatments are warranted

  12. Deformation-induced martensite and resistance to cavitation erosion

    International Nuclear Information System (INIS)

    Richman, R.H.

    1995-01-01

    Exposure to cavitating liquids can induce surface transformation in metastable alloys, notably the 18Cr-8Ni class of stainless steels. The question of whether such transformation contributes to erosion resistance has not been resolved. To address that issue, two metastable stainless steels (Types 301 and 304L) and a near-equiatomic NiTi alloy were subjected to cavitation. Magnetic measurements during and after cavitation erosion indicate that substantial reversion of deformation-induced martensite occurs in the highly deformed surface layers of the stainless steels. Thus, cyclic formation and reversion of martensite is deduced to be a non-trivial energy-adsorption mechanism in those steels. The extreme case of cyclic induction and essentially complete reversion of martensite is illustrated by superelastic NiTi, which is extraordinarily resistant to cavitation damage. (orig.)

  13. Transcriptomics and knockout mutant analysis of rhizobacteria-mediated induced systemic resistance in Arabidopsis

    NARCIS (Netherlands)

    Verhagen, B.W.M.

    2004-01-01

    A classic example of induced resistance is triggered after infection by a necrotizing pathogen, rendering uninfected,distal parts more resistant to subsequent pathogen attack, and is often referred to as systemic acquired resistance (SAR). A phenotypically comparable type of induced resistance is

  14. Paclitaxel Causes Electrophysiological Changes in the Anterior Cingulate Cortex via Modulation of the γ-Aminobutyric Acid-ergic System.

    Science.gov (United States)

    Nashawi, Houda; Masocha, Willias; Edafiogho, Ivan O; Kombian, Samuel B

    The aim of this study was to elucidate any electrophysiological changes that may contribute to the development of neuropathic pain during treatment with the anticancer drug paclitaxel, particularly in the γ-aminobutyric acid (GABA) system. One hundred and eight Sprague-Dawley rats were used (untreated control: 43; vehicle-treated: 21, and paclitaxel-treated: 44). Paclitaxel (8 mg/kg) was administered intraperitoneally on 2 alternate days to induce mechanical allodynia. The rats were sacrificed 7 days after treatment to obtain slices of the anterior cingulate cortex (ACC), a brain region involved in the central processing of pain. Field excitatory postsynaptic potentials (fEPSPs) were recorded in layer II/III of ACC slices, and stimulus-response curves were constructed. The observed effects were pharmacologically characterized by bath application of GABA and appropriate drugs to the slices. The paclitaxel-treated rats developed mechanical allodynia (i.e. reduced withdrawal threshold to mechanical stimuli). Slices from paclitaxel-treated rats produced a significantly higher maximal response (Emax) than those from untreated rats (p GABA (0.4 µM) reversed this effect and returned the excitability to a level similar to control. Pretreatment of the slices with the GABAB receptor blocker CGP 55845 (50 µM) increased Emax in slices from untreated rats (p GABA deficit in paclitaxel-treated rats compared to untreated ones. Such a deficit could contribute to the pathophysiology of paclitaxel-induced neuropathic pain (PINP). Thus, the GABAergic system might be a potential therapeutic target for managing PINP. © 2016 S. Karger AG, Basel.

  15. Inflammation-induced microvascular insulin resistance is an early event in diet-induced obesity

    Science.gov (United States)

    Zhao, Lina; Fu, Zhuo; Wu, Jing; Aylor, Kevin W.; Barrett, Eugene J.; Cao, Wenhong

    2015-01-01

    Endothelial dysfunction and vascular insulin resistance usually coexist and chronic inflammation engenders both. In the present study, we investigate the temporal relationship between vascular insulin resistance and metabolic insulin resistance. We assessed insulin responses in all arterial segments, including aorta, distal saphenous artery and the microvasculature, as well as the metabolic insulin responses in muscle in rats fed on a high-fat diet (HFD) for various durations ranging from 3 days to 4 weeks with or without sodium salicylate treatment. Compared with controls, HFD feeding significantly blunted insulin-mediated Akt (protein kinase B) and eNOS [endothelial nitric oxide (NO) synthase] phosphorylation in aorta in 1 week, blunted vasodilatory response in small resistance vessel in 4 weeks and microvascular recruitment in as early as 3 days. Insulin-stimulated whole body glucose disposal did not begin to progressively decrease until after 1 week. Salicylate treatment fully inhibited vascular inflammation, prevented microvascular insulin resistance and significantly improved muscle metabolic responses to insulin. We conclude that microvascular insulin resistance is an early event in diet-induced obesity and insulin resistance and inflammation plays an essential role in this process. Our data suggest microvascular insulin resistance contributes to the development of metabolic insulin resistance in muscle and muscle microvasculature is a potential therapeutic target in the prevention and treatment of diabetes and its related complications. PMID:26265791

  16. Paclitaxel Plasma Concentration after the First Infusion Predicts Treatment-Limiting Peripheral Neuropathy.

    Science.gov (United States)

    Hertz, Daniel L; Kidwell, Kelley M; Vangipuram, Kiran; Li, Feng; Pai, Manjunath P; Burness, Monika; Griggs, Jennifer J; Schott, Anne F; Van Poznak, Catherine; Hayes, Daniel F; Lavoie Smith, Ellen M; Henry, N Lynn

    2018-04-27

    Purpose: Paclitaxel exposure, specifically the maximum concentration ( C max ) and amount of time the concentration remains above 0.05 μmol/L ( T c >0.05 ), has been associated with the occurrence of paclitaxel-induced peripheral neuropathy. The objective of this study was to validate the relationship between paclitaxel exposure and peripheral neuropathy. Experimental Design: Patients with breast cancer receiving paclitaxel 80 mg/m 2 × 12 weekly doses were enrolled in an observational clinical study (NCT02338115). Paclitaxel plasma concentration was measured at the end of and 16-26 hours after the first infusion to estimate C max and T c >0.05 Patient-reported peripheral neuropathy was collected via CIPN20 at each dose, and an 8-item sensory subscale (CIPN8) was used in the primary analysis to test for an association with T c >0.05 Secondary analyses were conducted using C max as an alternative exposure parameter and testing each parameter with a secondary endpoint of the occurrence of peripheral neuropathy-induced treatment disruption. Results: In 60 subjects included in the analysis, the increase in CIPN8 during treatment was associated with baseline CIPN8, cumulative dose, and relative dose intensity ( P 0.05 ( P = 0.27) nor C max ( P = 0.99). In analyses of the secondary endpoint, cumulative dose (OR = 1.46; 95% confidence interval (CI), 1.18-1.80; P = 0.0008) and T c >0.05 (OR = 1.79; 95% CI, 1.06-3.01; P = 0.029) or C max (OR = 2.74; 95% CI, 1.45-5.20; P = 0.002) were associated with peripheral neuropathy-induced treatment disruption. Conclusions: Paclitaxel exposure is predictive of the occurrence of treatment-limiting peripheral neuropathy in patients receiving weekly paclitaxel for breast cancer. Studies are warranted to determine whether exposure-guided dosing enhances treatment effectiveness and/or prevents peripheral neuropathy in these patients. Clin Cancer Res; 1-9. ©2018 AACR. ©2018 American Association for Cancer Research.

  17. An Italian cost-effectiveness analysis of paclitaxel albumin (nab-paclitaxel) versus conventional paclitaxel for metastatic breast cancer patients: the COSTANza study

    Science.gov (United States)

    Lazzaro, Carlo; Bordonaro, Roberto; Cognetti, Francesco; Fabi, Alessandra; De Placido, Sabino; Arpino, Grazia; Marchetti, Paolo; Botticelli, Andrea; Pronzato, Paolo; Martelli, Elisa

    2013-01-01

    Purpose Paclitaxel albumin (nab-paclitaxel) is a nanoparticle albumin-bound paclitaxel formulation aimed at increasing therapeutic index in metastatic breast cancer. When compared to conventional paclitaxel, nab-paclitaxel has a reported longer time to progression, higher response, lower incidence of neutropenia, no need for premedication, shorter time of administration, and in pretreated metastatic breast cancer patients, extended overall survival. This study investigates the cost-effectiveness of nab-paclitaxel versus conventional paclitaxel for pretreated metastatic breast cancer patients in Italy. Materials and methods A Markov model with progression-free, progressed, and dead states was developed to estimate costs, outcomes, and quality adjusted life years over 5 years from the Italian National Health Service viewpoint. Patients were assumed to receive nab-paclitaxel 260 mg/m2 three times weekly or conventional paclitaxel 175 mg/m2 three times weekly. Data on health care resource consumption was collected from a convenience sample of five Italian centers. Resources were valued at Euro (€) 2011. Published utility weights were applied to health states to estimate the impact of response, disease progression, and adverse events on quality adjusted life years. Three sensitivity analyses tested the robustness of the base case incremental cost-effectiveness ratio (ICER). Results and conclusion Compared to conventional paclitaxel, nab-paclitaxel gains an extra 0.165 quality adjusted life years (0.265 life years saved) and incurs additional costs of €2506 per patient treated. This translates to an ICER of €15,189 (95% confidence interval: €11,891–€28,415). One-way sensitivity analysis underscores that ICER for nab-paclitaxel remains stable despite varying taxanes cost. Threshold analysis shows that ICER for nab-paclitaxel exceeds €40,000 only if cost per mg of conventional paclitaxel is set to zero. Probabilistic sensitivity analysis highlights that nab-paclitaxel

  18. Temperature-induced viral resistance in Emiliania huxleyi (Prymnesiophyceae).

    Science.gov (United States)

    Kendrick, B Jacob; DiTullio, Giacomo R; Cyronak, Tyler J; Fulton, James M; Van Mooy, Benjamin A S; Bidle, Kay D

    2014-01-01

    Annual Emiliania huxleyi blooms (along with other coccolithophorid species) play important roles in the global carbon and sulfur cycles. E. huxleyi blooms are routinely terminated by large, host-specific dsDNA viruses, (Emiliania huxleyi Viruses; EhVs), making these host-virus interactions a driving force behind their potential impact on global biogeochemical cycles. Given projected increases in sea surface temperature due to climate change, it is imperative to understand the effects of temperature on E. huxleyi's susceptibility to viral infection and its production of climatically active dimethylated sulfur species (DSS). Here we demonstrate that a 3°C increase in temperature induces EhV-resistant phenotypes in three E. huxleyi strains and that successful virus infection impacts DSS pool sizes. We also examined cellular polar lipids, given their documented roles in regulating host-virus interactions in this system, and propose that alterations to membrane-bound surface receptors are responsible for the observed temperature-induced resistance. Our findings have potential implications for global biogeochemical cycles in a warming climate and for deciphering the particular mechanism(s) by which some E. huxleyi strains exhibit viral resistance.

  19. Traumatic brain injury and obesity induce persistent central insulin resistance.

    Science.gov (United States)

    Karelina, Kate; Sarac, Benjamin; Freeman, Lindsey M; Gaier, Kristopher R; Weil, Zachary M

    2016-04-01

    Traumatic brain injury (TBI)-induced impairments in cerebral energy metabolism impede tissue repair and contribute to delayed functional recovery. Moreover, the transient alteration in brain glucose utilization corresponds to a period of increased vulnerability to the negative effects of a subsequent TBI. In order to better understand the factors contributing to TBI-induced central metabolic dysfunction, we examined the effect of single and repeated TBIs on brain insulin signalling. Here we show that TBI induced acute brain insulin resistance, which resolved within 7 days following a single injury but persisted until 28 days following repeated injuries. Obesity, which causes brain insulin resistance and neuroinflammation, exacerbated the consequences of TBI. Obese mice that underwent a TBI exhibited a prolonged reduction of Akt (also known as protein kinase B) signalling, exacerbated neuroinflammation (microglial activation), learning and memory deficits, and anxiety-like behaviours. Taken together, the transient changes in brain insulin sensitivity following TBI suggest a reduced capacity of the injured brain to respond to the neuroprotective and anti-inflammatory actions of insulin and Akt signalling, and thus may be a contributing factor for the damaging neuroinflammation and long-lasting deficits that occur following TBI. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  20. Galectin-1-Induced Autophagy Facilitates Cisplatin Resistance of Hepatocellular Carcinoma.

    Directory of Open Access Journals (Sweden)

    Yu-Chi Su

    Full Text Available Hepatocellular carcinoma (HCC is one of the most common cancers in Taiwan. Although chemotherapy is the primary treatment for HCC patients, drug resistance often leads to clinical failure. Galectin-1 is a beta-galactoside binding lectin which is up-regulated in HCC patients and promotes tumor growth by mediating cancer cell adhesion, migration and proliferation, but its role in chemoresistance of HCC is poorly understood. In this study we found that galectin-1 is able to lead to chemoresistance against cisplatin treatment, and subsequent inhibition has reversed the effect of cell death in HCC cells. Moreover, galectin-1 was found to induce autophagic flux in HCC cells. Inhibition of autophagy by inhibitors or knockdown of Atg5 cancels galectin-1-induced cisplatin resistance in HCC cells. Increase of mitophagy triggered by galectin-1 was found to reduce the mitochondrial potential loss and apoptosis induced by cisplatin treatment. Finally, using an in situ hepatoma mouse model, we clearly demonstrated that inhibition of galectin-1 by thiodigalactoside could significantly augment the anti-HCC effect of cisplatin. Taken together, our findings offer a new insight into the chemoresistance galectin-1 causes against cisplatin treatment, and points to a potential approach to improve the efficacy of cisplatin in the treatment of HCC patients.

  1. The battle of “nano” paclitaxel

    NARCIS (Netherlands)

    Sofias, Alexandros Marios; Dunne, Michael; Storm, Gert; Allen, Christine

    2017-01-01

    Paclitaxel (PTX) is one of the three most widely used chemotherapeutic agents, together with doxorubicin and cisplatin, and is first or second line treatment for several types of cancers. In 2000, Taxol, the conventional formulation of PTX, became the best-selling cancer drug of all time with annual

  2. Mildew resistant and less lodging wheat mutants induced in Iran

    International Nuclear Information System (INIS)

    Naghedi-Ahmadi, I.

    1989-01-01

    ''Tabassi'' is a lodging and mildew susceptible cultivar. To induce mutations, seeds were gamma irradiated (50 to 150 Gy) in 1982 and selection for lodging resistance was carried out in M 2 . During field experiments with the mutant lines in 1985/86 there has been a heavy mildew epidemic under which mutant 63-5-I (derived from 50 Gy treatment) exhibited considerable resistance and as a consequence, higher yield. The control was 100% infected, the mutant only 40%. The mutant yielded 31% more grain, 7.5% less straw and 4.5% more protein than the control. Lodging of 63-5-I was only 60% in an experiment under rainfed conditions in the same season, resulting in a relative yield increase of about 11%. In 1986/87 there was no mildew epidemic and the mutant yielded the same as ''Tabassi''

  3. Involvement of steatosis-induced glucagon resistance in hyperglucagonaemia

    DEFF Research Database (Denmark)

    Suppli, Malte P; Lund, Asger; Bagger, Jonatan I

    2016-01-01

    diabetes per se - is the main driver behind fasting hyperglucagonaemia. We hypothesise that in the majority of type 2 diabetic individuals hepatic sensitivity to glucagon is compromised due to hepatic steatosis, and that this provides a feedback mechanism acting at the level of pancreatic alpha cells...... recognised to play a significant role in type 2 diabetic pathophysiology. However, the mechanisms underlying disturbances in the regulation of glucagon remain unclear. Glucagon constitutes the primary stimulus for hepatic glucose production and, thus, upholds adequate blood glucose levels during fasting......, leading to elevated levels of glucagon. Here we present our hypothesis and propose a way to test it. If our hypothesis holds true, hepatic glucagon resistance would constitute a parallel to the obesity-induced insulin resistance in muscle and liver tissue, and underpin a central role for glucagon...

  4. Carboxylesterase-mediated insecticide resistance: Quantitative increase induces broader metabolic resistance than qualitative change.

    Science.gov (United States)

    Cui, Feng; Li, Mei-Xia; Chang, Hai-Jing; Mao, Yun; Zhang, Han-Ying; Lu, Li-Xia; Yan, Shuai-Guo; Lang, Ming-Lin; Liu, Li; Qiao, Chuan-Ling

    2015-06-01

    Carboxylesterases are mainly involved in the mediation of metabolic resistance of many insects to organophosphate (OP) insecticides. Carboxylesterases underwent two divergent evolutionary events: (1) quantitative mechanism characterized by the overproduction of carboxylesterase protein; and (2) qualitative mechanism caused by changes in enzymatic properties because of mutation from glycine/alanine to aspartate at the 151 site (G/A151D) or from tryptophan to leucine at the 271 site (W271L), following the numbering of Drosophila melanogaster AChE. Qualitative mechanism has been observed in few species. However, whether this carboxylesterase mutation mechanism is prevalent in insects remains unclear. In this study, wild-type, G/A151D and W271L mutant carboxylesterases from Culex pipiens and Aphis gossypii were subjected to germline transformation and then transferred to D. melanogaster. These germlines were ubiquitously expressed as induced by tub-Gal4. In carboxylesterase activity assay, the introduced mutant carboxylesterase did not enhance the overall carboxylesterase activity of flies. This result indicated that G/A151D or W271L mutation disrupted the original activities of the enzyme. Less than 1.5-fold OP resistance was only observed in flies expressing A. gossypii mutant carboxylesterases compared with those expressing A. gossypii wild-type carboxylesterase. However, transgenic flies universally showed low resistance to OP insecticides compared with non-transgenic flies. The flies expressing A. gossypii W271L mutant esterase exhibited 1.5-fold resistance to deltamethrin, a pyrethroid insecticide compared with non-transgenic flies. The present transgenic Drosophila system potentially showed that a quantitative increase in carboxylesterases induced broader resistance of insects to insecticides than a qualitative change. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Cultured hypothalamic neurons are resistant to inflammation and insulin resistance induced by saturated fatty acids.

    Science.gov (United States)

    Choi, Sun Ju; Kim, Francis; Schwartz, Michael W; Wisse, Brent E

    2010-06-01

    Hypothalamic inflammation induced by high-fat feeding causes insulin and leptin resistance and contributes to the pathogenesis of obesity. Since in vitro exposure to saturated fatty acids causes inflammation and insulin resistance in many cultured cell types, we determined how cultured hypothalamic neurons respond to this stimulus. Two murine hypothalamic neuronal cell cultures, N43/5 and GT1-7, were exposed to escalating concentrations of saturated fatty acids for up to 24 h. Harvested cells were evaluated for activation of inflammation by gene expression and protein content. Insulin-treated cells were evaluated for induction of markers of insulin receptor signaling (p-IRS, p-Akt). In both hypothalamic cell lines, inflammation was induced by prototypical inflammatory mediators LPS and TNFalpha, as judged by induction of IkappaBalpha (3- to 5-fold) and IL-6 (3- to 7-fold) mRNA and p-IkappaBalpha protein, and TNFalpha pretreatment reduced insulin-mediated p-Akt activation by 30% (P fatty acid (100, 250, or 500 microM for neurons, whereas they did in control muscle and endothelial cell lines. Despite the lack of evidence of inflammatory signaling, saturated fatty acid exposure in cultured hypothalamic neurons causes endoplasmic reticulum stress, induces mitogen-activated protein kinase, and causes apoptotic cell death with prolonged exposure. We conclude that saturated fatty acid exposure does not induce inflammatory signaling or insulin resistance in cultured hypothalamic neurons. Therefore, hypothalamic neuronal inflammation in the setting of DIO may involve an indirect mechanism mediated by saturated fatty acids on nonneuronal cells.

  6. Hypoxia-inducible factor-1α induces multidrug resistance protein in colon cancer

    Directory of Open Access Journals (Sweden)

    Lv Y

    2015-07-01

    Full Text Available Yingqian Lv, Shan Zhao, Jinzhu Han, Likang Zheng, Zixin Yang, Li Zhao Department of Oncology, The Second Hospital, Hebei Medical University, Shijiazhuang, Hebei Province, People’s Republic of China Abstract: Multidrug resistance is the major cause of chemotherapy failure in many solid tumors, including colon cancer. Hypoxic environment is a feature for all solid tumors and is important for the development of tumor resistance to chemotherapy. Hypoxia-inducible factor (HIF-1α is the key transcription factor that mediates cellular response to hypoxia. HIF-1α has been shown to play an important role in tumor resistance; however, the mechanism is still not fully understood. Here, we found that HIF-1α and the drug resistance-associated gene multidrug resistance associated protein 1 (MRP1 were induced by treatment of colon cancer cells with the hypoxia-mimetic agent cobalt chloride. Inhibition of HIF-1α by RNA interference and dominant-negative protein can significantly reduce the induction of MRP1 by hypoxia. Bioinformatics analysis showed that a hypoxia response element is located at -378 to -373 bp upstream of the transcription start site of MRP1 gene. Luciferase reporter assay combined with mutation analysis confirmed that this element is essential for hypoxia-mediated activation of MRP gene. Furthermore, RNA interference revealed that HIF-1α is necessary for this hypoxia-driven activation of MRP1 promoter. Importantly, chromatin immunoprecipitation analysis demonstrated that HIF-1α could directly bind to this HRE site in vivo. Together, these data suggest that MRP1 is a downstream target gene of HIF-1α, which provides a potential novel mechanism for HIF-1α-mediated drug resistance in colon cancer and maybe other solid tumors as well. Keywords: hypoxia, hypoxia-inducible factor-1α, multidrug resistance associated protein, transcriptional regulation, chemotherapy tolerance

  7. Role of PTEN in TNFα induced insulin resistance

    International Nuclear Information System (INIS)

    Bulger, David A.; Conley, Jermaine; Conner, Spencer H.; Majumdar, Gipsy; Solomon, Solomon S.

    2015-01-01

    Aims/hypothesis: PTEN may play a reversible role in TNFα induced insulin resistance, which has been linked to obesity-associated insulin resistance (IR). Methods: Western blots for PTEN and p-Akt were performed on H-411E liver cells incubated with insulin, TNFα, and in selected experiments VO-OHpic vanadium complex in the presence and absence of PTEN siRNA. Total PTEN was compared to β-actin loading control and p-Akt was compared to total Akt. Results: Western blot and Real Time RT-PCR experiments showed increased PTEN after TNFα treatment (p = 0.04); slightly decreased PTEN after insulin treatment; and slightly increased PTEN after insulin + TNFα treatment. PTEN siRNA markedly inhibited the TNFα-induced increase in PTEN (p < 0.01) without significantly changing the p-Akt levels. The vanadium complex, exhibiting insulin-like effects, also significantly prevented the TNFα-induced increase in PTEN. Combining insulin and VO-OHpic was additive, providing both proof of concept and insight into mechanism. Discussion: The PTEN increase due to TNFα treatment was reversible by both PTEN siRNA knockdown and VO-OHpic treatment. Thus, PTEN is identified as a potential new therapeutic target for reducing IR in Type 2 DM. - Highlights: • TNFα treatment induced a significant increase in PTEN in H-411E liver cells. • PTEN siRNA knockdown prevented this effect. • VO-OHpic (vanadium complex) treatment, like insulin, decreased PTEN protein levels. • Thus, PTEN is identified as a potential therapeutic target in DM Type 2

  8. Role of PTEN in TNFα induced insulin resistance

    Energy Technology Data Exchange (ETDEWEB)

    Bulger, David A. [Departments of Medicine and Pharmacology, University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Medicine and Research Services, Veterans Association Medical Center, Memphis, TN 38104 (United States); Wellcome Trust Medical Research Council Institute of Metabolic Science, Cambridge CB2 0QQ (United Kingdom); National Institute of Diabetes & Digestive & Kidney Disease, National Institutes of Health, Bethesda, MD 20892 (United States); Conley, Jermaine [Medicine and Research Services, Veterans Association Medical Center, Memphis, TN 38104 (United States); Conner, Spencer H.; Majumdar, Gipsy [Departments of Medicine and Pharmacology, University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Medicine and Research Services, Veterans Association Medical Center, Memphis, TN 38104 (United States); Solomon, Solomon S., E-mail: ssolomon@uthsc.edu [Departments of Medicine and Pharmacology, University of Tennessee Health Science Center, Memphis, TN 38163 (United States); Medicine and Research Services, Veterans Association Medical Center, Memphis, TN 38104 (United States)

    2015-06-05

    Aims/hypothesis: PTEN may play a reversible role in TNFα induced insulin resistance, which has been linked to obesity-associated insulin resistance (IR). Methods: Western blots for PTEN and p-Akt were performed on H-411E liver cells incubated with insulin, TNFα, and in selected experiments VO-OHpic vanadium complex in the presence and absence of PTEN siRNA. Total PTEN was compared to β-actin loading control and p-Akt was compared to total Akt. Results: Western blot and Real Time RT-PCR experiments showed increased PTEN after TNFα treatment (p = 0.04); slightly decreased PTEN after insulin treatment; and slightly increased PTEN after insulin + TNFα treatment. PTEN siRNA markedly inhibited the TNFα-induced increase in PTEN (p < 0.01) without significantly changing the p-Akt levels. The vanadium complex, exhibiting insulin-like effects, also significantly prevented the TNFα-induced increase in PTEN. Combining insulin and VO-OHpic was additive, providing both proof of concept and insight into mechanism. Discussion: The PTEN increase due to TNFα treatment was reversible by both PTEN siRNA knockdown and VO-OHpic treatment. Thus, PTEN is identified as a potential new therapeutic target for reducing IR in Type 2 DM. - Highlights: • TNFα treatment induced a significant increase in PTEN in H-411E liver cells. • PTEN siRNA knockdown prevented this effect. • VO-OHpic (vanadium complex) treatment, like insulin, decreased PTEN protein levels. • Thus, PTEN is identified as a potential therapeutic target in DM Type 2.

  9. Differential effectiveness of salicylate-dependent and jasmonate/ethylene-dependent induced resistance in Arabidopsis

    NARCIS (Netherlands)

    Ton, J.; Pelt, J.A. van; Loon, L.C. van; Pieterse, C.M.J.

    2002-01-01

    Salicylic acid (SA), jasmonic acid (JA), and ethylene (ET) are each involved in the regulation of basal resistance against different pathogens. These three signals play important roles in induced resistance as well. SA is a key regulator of pathogen-induced systemic acquired resistance (SAR),

  10. Identification of genes involved in rhizobacteria-mediated induced systemic resistance in Arabidopsis

    NARCIS (Netherlands)

    Léon-Kloosterziel, K.M.; Verhagen, B.W.M.; Keurentjes, J.J.B.; Loon, L.C. van; Pieterse, C.M.J.

    2002-01-01

    Different forms of biologically induced disease resistance have been identified in plants. Following attack by a necrotizing pathogen systemic acquired resistance (SAR) is induced, leading to a broad-spectrum disease resistance that is associated with an increase in salicylic acid (SA) levels

  11. Macrophage-secreted factors induce adipocyte inflammation and insulin resistance

    International Nuclear Information System (INIS)

    Permana, Paska A.; Menge, Christopher; Reaven, Peter D.

    2006-01-01

    Macrophage infiltration into adipose tissue increases with obesity, a condition associated with low-grade inflammation and insulin resistance. We investigated the direct effects of macrophage-secreted factors on adipocyte inflammation and insulin resistance. 3T3-L1 adipocytes incubated with media conditioned by RAW264.7 macrophages (RAW-CM) showed dramatically increased transcription of several inflammation-related genes, greater nuclear factor kappa B (NF-κB) activity, and enhanced binding of U937 monocytes. All of these effects were prevented by co-incubation with pyrrolidinedithiocarbamate, an NF-κB inhibitor. Adipocytes incubated with RAW-CM also released more non-esterified fatty acids and this increased lipolysis was not suppressed by insulin. In addition, RAW-CM treatment decreased insulin-stimulated glucose uptake in adipocytes. Taken together, these results indicate that macrophage-secreted factors induce inflammatory responses and reduce insulin responsiveness in adipocytes. These effects of macrophage-secreted factors on adipocytes may contribute significantly to the systemic inflammation and insulin resistance associated with obesity

  12. Monomeric tartrate resistant acid phosphatase induces insulin sensitive obesity.

    Directory of Open Access Journals (Sweden)

    Pernilla Lång

    2008-03-01

    Full Text Available Obesity is associated with macrophage infiltration of adipose tissue, which may link adipose inflammation to insulin resistance. However, the impact of inflammatory cells in the pathophysiology of obesity remains unclear. Tartrate resistant acid phosphatase (TRAP is an enzyme expressed by subsets of macrophages and osteoclasts that exists either as an enzymatically inactive monomer or as an active, proteolytically processed dimer.Using mice over expressing TRAP, we show that over-expression of monomeric, but not the dimeric form in adipose tissue leads to early onset spontaneous hyperplastic obesity i.e. many small fat cells. In vitro, recombinant monomeric, but not proteolytically processed TRAP induced proliferation and differentiation of mouse and human adipocyte precursor cells. In humans, monomeric TRAP was highly expressed in the adipose tissue of obese individuals. In both the mouse model and in the obese humans the source of TRAP in adipose tissue was macrophages. In addition, the obese TRAP over expressing mice exhibited signs of a low-grade inflammatory reaction in adipose tissue without evidence of abnormal adipocyte lipolysis, lipogenesis or insulin sensitivity.Monomeric TRAP, most likely secreted from adipose tissue macrophages, induces hyperplastic obesity with normal adipocyte lipid metabolism and insulin sensitivity.

  13. Heterogeneity in induced thermal resistance of rat tumor cell clones

    International Nuclear Information System (INIS)

    Tomasovic, S.P.; Rosenblatt, P.L.; Heitzman, D.

    1983-01-01

    Four 13762NF rat mammary adenocarcinoma clones were examined for their survival response to heating under conditions that induced transient thermal resistance (thermotolerance). Clones MTC and MTF7 were isolated from the subcutaneous locally growing tumor, whereas clones MTLn2 and MTLn3 were derived from spontaneous lung metastases. There was heterogeneity among these clones in thermotolerance induced by either fractionated 45 0 C or continuous 42 0 C heating, but the order of sensitivity was not necessarily the same. The clones developed thermal resistance at different rates and to different degrees within the same time intervals. There was heterogeneity between clones isolated from within either the primary site or metastatic lesions. However, clones derived from metastatic foci did not intrinsically acquire more or less thermotolerance to fractionated 45 0 C or continuous 42 0 C heating than did clones from the primary tumor. Further, there was no apparent relationship between any phenotypic properties that conferred more or less thermotolerance in vitro and any phenotypic properties that conferred enhanced metastatic success of these same clones by spontaneous (subcutaneous) or experimental (intravenous) routes in vivo. These tumor clones also differ in their karyotype, metastatic potential, cell surface features, sensitivity to x-irradiation and drugs, and ability to repair sublethal radiation damage. These results provide further credence to the concept that inherent heterogeneity within tumors may be as important in therapeutic success as other known modifiers of outcome such as site and treatment heterogeneity

  14. Induced resistance to the antimicrobial peptide lactoferricin B in Staphylococcus aureus.

    Science.gov (United States)

    Samuelsen, Orjan; Haukland, Hanne H; Jenssen, Håvard; Krämer, Manuela; Sandvik, Kjersti; Ulvatne, Hilde; Vorland, Lars H

    2005-06-20

    This study was designed to investigate inducible intrinsic resistance against lactoferricin B in Staphylococcus aureus. Serial passage of seven S. aureus strains in medium with increasing concentrations of peptide resulted in an induced resistance at various levels in all strains. The induced resistance was unstable and decreased relatively rapidly during passages in peptide free medium but the minimum inhibitory concentration remained elevated after thirty passages. Cross-resistance to penicillin G and low-level cross-resistance to the antimicrobial peptides indolicidin and Ala(8,13,18)-magainin-II amide [corrected] was observed. No cross-resistance was observed to the human cathelicidin LL-37. In conclusion, this study shows that S. aureus has intrinsic resistance mechanisms against antimicrobial peptides that can be induced upon exposure, and that this may confer low-level cross-resistance to other antimicrobial peptides.

  15. Pre-cold stress increases acid stress resistance and induces amino ...

    African Journals Online (AJOL)

    Pre-cold stress increases acid stress resistance and induces amino acid homeostasis in Lactococcus lactis NZ9000. ... Purpose: To investigate the effects of pre-cold stress treatments on subsequent acid stress resistance ... from 32 Countries:.

  16. Clinically Relevant Anticancer Polymer Paclitaxel Therapeutics

    Directory of Open Access Journals (Sweden)

    Danbo Yang

    2010-12-01

    Full Text Available The concept of utilizing polymers in drug delivery has been extensively explored for improving the therapeutic index of small molecule drugs. In general, polymers can be used as polymer-drug conjugates or polymeric micelles. Each unique application mandates its own chemistry and controlled release of active drugs. Each polymer exhibits its own intrinsic issues providing the advantage of flexibility. However, none have as yet been approved by the U.S. Food and Drug Administration. General aspects of polymer and nano-particle therapeutics have been reviewed. Here we focus this review on specific clinically relevant anticancer polymer paclitaxel therapeutics. We emphasize their chemistry and formulation, in vitro activity on some human cancer cell lines, plasma pharmacokinetics and tumor accumulation, in vivo efficacy, and clinical outcomes. Furthermore, we include a short review of our recent developments of a novel poly(L-g-glutamylglutamine-paclitaxel nano-conjugate (PGG-PTX. PGG-PTX has its own unique property of forming nano-particles. It has also been shown to possess a favorable profile of pharmacokinetics and to exhibit efficacious potency. This review might shed light on designing new and better polymer paclitaxel therapeutics for potential anticancer applications in the clinic.

  17. Clinically Relevant Anticancer Polymer Paclitaxel Therapeutics

    International Nuclear Information System (INIS)

    Yang, Danbo; Yu, Lei; Van, Sang

    2010-01-01

    The concept of utilizing polymers in drug delivery has been extensively explored for improving the therapeutic index of small molecule drugs. In general, polymers can be used as polymer-drug conjugates or polymeric micelles. Each unique application mandates its own chemistry and controlled release of active drugs. Each polymer exhibits its own intrinsic issues providing the advantage of flexibility. However, none have as yet been approved by the U.S. Food and Drug Administration. General aspects of polymer and nano-particle therapeutics have been reviewed. Here we focus this review on specific clinically relevant anticancer polymer paclitaxel therapeutics. We emphasize their chemistry and formulation, in vitro activity on some human cancer cell lines, plasma pharmacokinetics and tumor accumulation, in vivo efficacy, and clinical outcomes. Furthermore, we include a short review of our recent developments of a novel poly(l-γ-glutamylglutamine)-paclitaxel nano-conjugate (PGG-PTX). PGG-PTX has its own unique property of forming nano-particles. It has also been shown to possess a favorable profile of pharmacokinetics and to exhibit efficacious potency. This review might shed light on designing new and better polymer paclitaxel therapeutics for potential anticancer applications in the clinic

  18. Clinically Relevant Anticancer Polymer Paclitaxel Therapeutics

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Danbo [Biomedical Engineering and Technology Institute, Institutes for Advanced Interdisciplinary Research, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062 (China); Yu, Lei, E-mail: yu-lei@gg.nitto.co.jp [Biomedical Engineering and Technology Institute, Institutes for Advanced Interdisciplinary Research, East China Normal University, 3663 North Zhongshan Road, Shanghai, 200062 (China); Biomedical Group, Nitto Denko Technical Corporation, 501 Via Del Monte, Oceanside, CA 92058 (United States); Van, Sang [Biomedical Group, Nitto Denko Technical Corporation, 501 Via Del Monte, Oceanside, CA 92058 (United States)

    2010-12-23

    The concept of utilizing polymers in drug delivery has been extensively explored for improving the therapeutic index of small molecule drugs. In general, polymers can be used as polymer-drug conjugates or polymeric micelles. Each unique application mandates its own chemistry and controlled release of active drugs. Each polymer exhibits its own intrinsic issues providing the advantage of flexibility. However, none have as yet been approved by the U.S. Food and Drug Administration. General aspects of polymer and nano-particle therapeutics have been reviewed. Here we focus this review on specific clinically relevant anticancer polymer paclitaxel therapeutics. We emphasize their chemistry and formulation, in vitro activity on some human cancer cell lines, plasma pharmacokinetics and tumor accumulation, in vivo efficacy, and clinical outcomes. Furthermore, we include a short review of our recent developments of a novel poly(l-γ-glutamylglutamine)-paclitaxel nano-conjugate (PGG-PTX). PGG-PTX has its own unique property of forming nano-particles. It has also been shown to possess a favorable profile of pharmacokinetics and to exhibit efficacious potency. This review might shed light on designing new and better polymer paclitaxel therapeutics for potential anticancer applications in the clinic.

  19. Treatment of amiodarone-induced thyrotoxicosis resistant to conventional therapy

    Directory of Open Access Journals (Sweden)

    Nišić Tanja

    2017-01-01

    Full Text Available Introduction: Amiodarone as an antiarrhythmic medication is necessary in the prevention and treatment of malignant ventricular arrhythmias, however, it can induce thyroid dysfunction. Thyroid dysfunction may be either hypothyroidism or thyrotoxicosis, however, 50% of patients who have used amiodarone are euthyroid. Case report: A 27-year-old female patient, hospitalized at the Clinic for Endocrinology due to type 2 amiodarone-induced thyrotoxicosis. The patient had previously received amiodarone for two years. At age 25, the patient was diagnosed with dilated cardiomyopathy (EF 25%, EDD/ESD 56-57/47 mm with mild Ebstein’s anomaly, WPW Sy and recorded episodes of non-sustained VT. In order to reduce the risk of sudden death and prevent malignant ventricular arrhythmias, ICD-VR was implanted and amiodarone was prescribed. Treatment with propylthiouracil (PTU and dexamethasone was initiated after thyrotoxicosis was diagnosed. Three weeks after the introduction of PTU, hepatotoxicity was registered, thus the medication was discontinued. Thyrozol, which regulates the hepatotoxicity parameters, was introduced. Sodium perchlorate and glucocorticoid (per os, IV and intrathyroidal therapy was introduced. The treatment had lasted for fifty days and laboratory signs of thyrotoxicosis were still present, which is why a total of eight plasmapheresis sessions were performed. Each plasmapheresis resulted in a significant decrease in FT4 and a slight decrease in FT3. After seventy two days of treatment, an optimal hormonal status of the thyroid gland was established and total thyroidectomy was performed. Conclusion: Patient was treated for amiodarone-induced thyrotoxicosis (AIT type 2, which was resistant to conventional therapy for a long period of time. Successful treatment was achieved by applying plasmapheresis although the effect of perchlorate and glucocorticoids application cannot be disregarded.

  20. X-ray-induced mutants resistant to 8-azaguanine

    International Nuclear Information System (INIS)

    Carver, J.H.; Dewey, W.C.; Hopwood, L.E.

    1976-01-01

    Asynchronous Chinese hamster ovary cells were irradiated and colony survival in Alpha MEM medium with dialyzed serum was determined with or without 15 μg/ml 8-Azaguanine (AG). Data indicated that a reproducible assay for the system was dependent upon controlling cell density at least two days prior to induction as well as throughout the expression period. Generally, spontaneous and radiation-induced mutant frequencies decreased when cell densities exceeded a critical density of 3-6 x 10 4 cells/cm 2 . Infrequently, the critical density was exceeded by a factor of two with no observed decrease, possibly correlated with a longer cell doubling time. Drug depletion artifacts can occur because of drug degradation, or because wild-type cells utilize the drug or produce conditions which reduce uptake of the drug. Thus, as the effective drug concentration is lowered, the observed mutant frequency increases because a spectrum of mutants resistant to only low concentrations can now survive. In fact, refeeding with AG at intervals during the incubation period lowered spontaneous and radiation-induced frequencies approx. 5-fold. Therefore, to standardize conditions, cells were trypsinized at the end of the expression time and replated at a constant cell number for mutant selection by AG. Over two generations of growth during the expression period were required for optimal manifestation of induced mutants, and when densities were kept below 4 x 10 4 cells/cm 2 at all times, observed mutant frequencies did not change significantly over a period between 80 and 140 h post-induction (over 4 generations for irradiated cells and over 6 generations for controls). Previous reports of observed mutant frequencies decreasing beyond three generations may be due to cell interaction prior to mutant selection

  1. Downy mildew resistance induced by Trichoderma harzianum T39 in susceptible grapevines partially mimics transcriptional changes of resistant genotypes

    Science.gov (United States)

    2012-01-01

    Background Downy mildew, caused by Plasmopara viticola, is one of the most severe diseases of grapevine and is commonly controlled by fungicide treatments. The beneficial microorganism Trichoderma harzianum T39 (T39) can induce resistance to downy mildew, although the molecular events associated with this process have not yet been elucidated in grapevine. A next generation RNA sequencing (RNA-Seq) approach was used to study global transcriptional changes associated with resistance induced by T39 in Vitis vinifera Pinot Noir leaves. The long-term aim was to develop strategies to optimize the use of this agent for downy mildew control. Results More than 14.8 million paired-end reads were obtained for each biological replicate of T39-treated and control leaf samples collected before and 24 h after P. viticola inoculation. RNA-Seq analysis resulted in the identification of 7,024 differentially expressed genes, highlighting the complex transcriptional reprogramming of grapevine leaves during resistance induction and in response to pathogen inoculation. Our data show that T39 has a dual effect: it directly modulates genes related to the microbial recognition machinery, and it enhances the expression of defence-related processes after pathogen inoculation. Whereas several genes were commonly affected by P. viticola in control and T39-treated plants, opposing modulation of genes related to responses to stress and protein metabolism was found. T39-induced resistance partially inhibited some disease-related processes and specifically activated defence responses after P. viticola inoculation, causing a significant reduction of downy mildew symptoms. Conclusions The global transcriptional analysis revealed that defence processes known to be implicated in the reaction of resistant genotypes to downy mildew were partially activated by T39-induced resistance in susceptible grapevines. Genes identified in this work are an important source of markers for selecting novel

  2. Apparent resistivity and spectral induced polarization in the submarine environment

    Directory of Open Access Journals (Sweden)

    HERCULES DE SOUZA

    2001-09-01

    Full Text Available Relatively few investigations have employed electrical methods in the submarine environment, which may be promising for mineral deposits or threatened by environmental problems. We have measured the electric field using both disk and bar electrodes in the sea water at three different levels: sea surface, seven meters deep, and sea bottom at a depth of ten meters, employing a 2 m spacing dipole-dipole array with 7 array spacings of investigation, and 13 values of frequencies at steps of (2N hertz, N = -2, -1, 0, 1, 2,.....10. The measurement allowed the analysis of the electric field as a function of frequency and spacing, and of the spectral induced polarization. Modelling and interpretation of the apparent resistivity yielded a good fit with previous drilling data. Analysis of the spectrum of the complex apparent resistivity and the comparison with equivalent circuits, provided information about the grain size, the mineral composition and the major induced polarization phenomenon occurring below the sea. Therefore the result of the present research show the feasibility of measuring the variation of seawater resistivity in situ, as well as the resistivity of sea bottom sediments.Relativamente poucas investigações têm empregado métodos elétricos no ambiente submarino, o qual pode ser promissor para depósitos minerais ou ameaçado por problemas ambientais. Nós medimos o campo elétrico usando eletrodos em forma de disco e de barra na água do mar, em três níveis distintos: superfície, sete metros de profundidade, e fundo do mar a dez metros de profundidade, empregando um dispositivo dipolo-dipolo com 2m de afastamento, 7 níveis de investigação e 13 valores de freqüência a intervalos de (2N hertz, N = -2, -1, 0, 1, 2, ... 10. A medida permitiu a análise do campo elétrico como uma função de freqüência e afastamento, e da polarização induzida espectral. A modelagem e a interpretação da resistividade aparente se ajustaram bem

  3. Field-induced resistance switching at metal/perovskite manganese oxide interface

    International Nuclear Information System (INIS)

    Ohkubo, I.; Tsubouchi, K.; Harada, T.; Kumigashira, H.; Itaka, K.; Matsumoto, Y.; Ohnishi, T.; Lippmaa, M.; Koinuma, H.; Oshima, M.

    2008-01-01

    Planar type metal/insulator/metal structures composed of an epitaxial perovskite manganese oxide layer and various metal electrodes were prepared for electric-field-induced resistance switching. Only the electrode pairs including Al show good resistance switching and the switching ratio reaches its maximum of 1000. This resistance switching occurs around the interface between Al electrodes and epitaxial perovskite manganese oxide thin films

  4. Induced resistance in plants and the role of pathogenesis-related proteins

    NARCIS (Netherlands)

    Loon, L.C. van

    1997-01-01

    The nature of induced resistance Resistance, according to Agrios (1988) is the ability of an organism to exclude or overcome, completely or in some degree, the effect of a pathogen or other damaging factor. Disease resistance in plants is manifested by limited symptoms, reflecting the

  5. Growth hormone-induced insulin resistance in human subjects involves reduced pyruvate dehydrogenase activity

    DEFF Research Database (Denmark)

    Nellemann, B.; Vendelbo, M.H.; Nielsen, Thomas Svava

    2014-01-01

    Insulin resistance induced by growth hormone (GH) is linked to promotion of lipolysis by unknown mechanisms. We hypothesized that suppression of the activity of pyruvate dehydrogenase in the active form (PDHa) underlies GH-induced insulin resistance similar to what is observed during fasting....

  6. Autophagy is induced by resistance exercise in young men but unfolded protein response is induced regardless of age.

    Science.gov (United States)

    Hentilä, Jaakko; Ahtiainen, Juha P; Paulsen, Gøran; Raastad, Truls; Häkkinen, Keijo; Mero, Antti A; Hulmi, Juha J

    2018-04-02

    Autophagy and unfolded protein response (UPR) appear to be important for skeletal muscle homeostasis and may be altered by exercise. Our aim was to investigate the effects of resistance exercise and training on indicators of UPR and autophagy in healthy untrained young men (n = 12, 27 ± 4 years) and older men (n = 8, 61 ± 6 years) as well as in resistance-trained individuals (n = 15, 25 ± 5 years). Indicators of autophagy and UPR were investigated from the muscle biopsies after a single resistance exercise bout and after 21 weeks of resistance training. Lipidated LC3II as an indicator of autophagosome content increased at 48 hours post resistance exercise (P resistance-training period (P resistance exercise in untrained young and older men (P resistance-training period regardless of age. UPR was unchanged within the first few hours after the resistance exercise bout regardless of the training status. Changes in autophagy and UPR ER indicators did not correlate with a resistance-training-induced increase in muscle strength and size. Autophagosome content is increased by resistance training in young previously untrained men, but this response may be blunted by aging. However, unfolded protein response is induced by an unaccustomed resistance exercise bout in a delayed manner regardless of age. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  7. Metabolomics Analysis of Hormone-Responsive and Triple-Negative Breast Cancer Cell Responses to Paclitaxel Identify Key Metabolic Differences.

    Science.gov (United States)

    Stewart, Delisha A; Winnike, Jason H; McRitchie, Susan L; Clark, Robert F; Pathmasiri, Wimal W; Sumner, Susan J

    2016-09-02

    To date, no targeted therapies are available to treat triple negative breast cancer (TNBC), while other breast cancer subtypes are responsive to current therapeutic treatment. Metabolomics was conducted to reveal differences in two hormone receptor-negative TNBC cell lines and two hormone receptor-positive Luminal A cell lines. Studies were conducted in the presence and absence of paclitaxel (Taxol). TNBC cell lines had higher levels of amino acids, branched-chain amino acids, nucleotides, and nucleotide sugars and lower levels of proliferation-related metabolites like choline compared with Luminal A cell lines. In the presence of paclitaxel, each cell line showed unique metabolic responses, with some similarities by type. For example, in the Luminal A cell lines, levels of lactate and creatine decreased while certain choline metabolites and myo-inositol increased with paclitaxel. In the TNBC cell lines levels of glutamine, glutamate, and glutathione increased, whereas lysine, proline, and valine decreased in the presence of drug. Profiling secreted inflammatory cytokines in the conditioned media demonstrated a greater response to paclitaxel in the hormone-positive Luminal cells compared with a secretion profile that suggested greater drug resistance in the TNBC cells. The most significant differences distinguishing the cell types based on pathway enrichment analyses were related to amino acid, lipid and carbohydrate metabolism pathways, whereas several biological pathways were differentiated between the cell lines following treatment.

  8. Tumor therapy with a urokinase plasminogen activator-activated anthrax lethal toxin alone and in combination with paclitaxel.

    Science.gov (United States)

    Wein, Alexander N; Liu, Shihui; Zhang, Yi; McKenzie, Andrew T; Leppla, Stephen H

    2013-02-01

    PA-U2, an engineered anthrax protective antigen that is activated by urokinase was combined with wildtype lethal factor in the treatment of Colo205 colon adenocarcinoma in vitro and B16-BL6 mouse melanoma in vitro and in vivo. This therapy was also tested in combination with the small molecule paclitaxel, based on prior reports suggesting synergy between ERK1/2 inhibition and chemotherapeutics. Colo205 was sensitive to PA-U2/LF while B16-BL6 was not. For the combination treatment of B16-BL6, paclitaxel showed a dose response in vitro, but cells remained resistant to PA-U2/LF even in the presence of paclitaxel. In vivo, each therapy slowed tumor progression, and an additive effect between the two was observed. Since LF targets tumor vasculature while paclitaxel is an antimitotic, it is possible the agents were acting against different cells in the stroma, precluding a synergistic effect. The engineered anthrax toxin PA-U2/LF warrants further development and testing, possibly in combination with an antiangiogenesis therapy such as sunitinib or sorafinib.

  9. Anaesthesia generates neuronal insulin resistance by inducing hypothermia

    Directory of Open Access Journals (Sweden)

    Sutherland Calum

    2008-10-01

    Full Text Available Abstract Background Anaesthesia is commonly employed prior to surgical investigations and to permit icv injections in rodents. Indeed it is standard practise in many studies examining the subsequent actions of hormones and growth factors on the brain. Recent evidence that the basal activity of specific intracellular signalling proteins can be affected by anaesthesia prompted us to examine the effect of anaesthesia not only on the basal activity but also the insulin sensitivity of the major insulin signalling pathways. Results We find that urethane- and ketamine-induced anaesthesia results in rapid activation of the phosphatidylinositol (PI 3-kinase-protein kinase B (PKB signalling pathway in the brain, increases tau phosphorylation while at the same time reducing basal activity of the Ras-ERK pathway. Subsequent injection of insulin does not alter the activity of either the PI 3-kinase or ERK signalling pathways, indicating a degree of neuronal molecular insulin resistance. However, if body temperature is maintained during anaesthesia then there is no alteration in the basal activity of these signalling molecules. Subsequent response of both pathways to insulin injection is restored. Conclusion The data is consistent with a hypothermia related alteration in neuronal signalling following anaesthesia, and emphasises the importance of maintaining the body temperature of rodents when monitoring insulin (or growth factor/neurotrophic agent action in the brain of anesthetised rodents.

  10. Subinhibitory concentrations of imipenem induce increased resistance to methicillin and imipenem in vitro in methicillin-resistant Staphylococcus aureus.

    OpenAIRE

    Forbes, B A; McClatchey, K D; Schaberg, D R

    1984-01-01

    Methicillin-resistant (MR) Staphylococcus aureus that was susceptible to less than 0.75 micrograms of imipenem per ml demonstrated inducible resistance. MR S. aureus preincubated with 0.05 microgram of imipenem per ml grew in medium with an imipenem concentration of 32 micrograms/ml, and methicillin MICs increased 20-fold. Non-MR S. aureus exhibited no induction. Preincubation with methicillin produced no effect. Induction appeared to be a unique interaction of imipenem with MR S. aureus.

  11. Hypersensitivity reaction studies of a polyethoxylated castor oil-free, liposome-based alternative paclitaxel formulation.

    Science.gov (United States)

    Wang, Hongbo; Cheng, Guang; Du, Yuan; Ye, Liang; Chen, Wenzhong; Zhang, Leiming; Wang, Tian; Tian, Jingwei; Fu, Fenghua

    2013-03-01

    The commercial drug paclitaxel (Taxol) may introduce hypersensitivity reactions associated with the polyethoxylated castor oil-ethanol solvent. To overcome these problems, we developed a polyethoxylated castor oil-free, liposome-based alternative paclitaxel formulation, known as Lipusu. In this study, we performed in vitro and in vivo experiments to compare the safety profiles of Lipusu and Taxol, with special regard to hypersensitivity reactions. First, Swiss mice were used to determine the lethal dosages, and then to evaluate hypersensitivity reactions, followed by histopathological examination and enzyme-linked immunosorbent assays (ELISAs) of serum SC5b-9 and lung histamine. Additionally, healthy human serum was used to analyze in vitro complement activation. Finally, an MTT assay was used to determine the in vitro anti-proliferation activity. Our data clearly showed that Lipusu displayed a much higher safety margin and did not induce hypersensitivity or hypersensitivity-related lung lesions, which may be associated with the fact that Lipusu did not activate complement or increase histamine release in vivo. Moreover, Lipusu did not promote complement activation in healthy human serum in vitro, and demonstrated anti-proliferative activity against human cancer cells, similar to that of Taxol. Therefore, the improved formulation of paclitaxel, which exhibited a much better safety profile and comparable cytotoxic activity to Taxol, may bring a number of benefits to cancer patients.

  12. Use of gamma radiation for inducing rust resistance in soybean

    International Nuclear Information System (INIS)

    Smutkupt, Sumit; Wongpiyasatid, Arunee; Lamseejan, Siranut; Naritoom, Kruik

    1982-01-01

    Experiments on induced mutations for rust resistance in 11 soybean cultivars were started in the rainy season of 1979. M 1 seeds were grown at Farm Suwan, Pak Chong, Nakorn Rajchasima Province. Six plods from each of 4,438 control and 43,907 M 1 plants were randomly harvested. M 2 seeds of each cultivar of different doses were bulked. In addition, 270 good M 1 plants were selected and threshed singly. M 2 -bulk and M 2 -single seeds were advanced to M 3 . Both of M 3 -bulk and M 3 -single plants together with M 2 -bulk plants derived from remnant M 2 seeds were screened for rust resistance in the rainy season of 1980. The IWGSR rust rating system was used. Based on the slow growth of rust reaction on the plant (323,333) compared with the average IWGSR rust rating notation of the rates (343) in the same row, 121 plants were selected. Among them, six were selected from a total of 2802 control plants, and 115 from a total of 28,834 M 2 and M 3 plants. Seeds of each selection harvested. Only 88 lines of M 4 and M 5 were available for further rust evaluation in the rainy season of 1981. The results were as follows: At 77 days after planting, 82 selected lines were rated 333, 323 in comparison with 87 out of 137 rows of control S.J.1, S.J.2, S.J.4 and T.K.5 were rated 343. At 86 days after planting, most of the selections reached the diseased level 343. However, six lines which were derived from G8586 were still rated 333. In addition, a plant with slow growth of rust (323) from Taichung N No. 81-1-032 was selected. The six selected lines having characteristics of slow growth of rust reaction on the plants will be further tested. The high yielding selections among 82 selected lines having low percentage of shrivelled seeds will be used for further yield evaluation in the rainy season of 1982

  13. Identifying clinically relevant drug resistance genes in drug-induced resistant cancer cell lines and post-chemotherapy tissues.

    Science.gov (United States)

    Tong, Mengsha; Zheng, Weicheng; Lu, Xingrong; Ao, Lu; Li, Xiangyu; Guan, Qingzhou; Cai, Hao; Li, Mengyao; Yan, Haidan; Guo, You; Chi, Pan; Guo, Zheng

    2015-12-01

    Until recently, few molecular signatures of drug resistance identified in drug-induced resistant cancer cell models can be translated into clinical practice. Here, we defined differentially expressed genes (DEGs) between pre-chemotherapy colorectal cancer (CRC) tissue samples of non-responders and responders for 5-fluorouracil and oxaliplatin-based therapy as clinically relevant drug resistance genes (CRG5-FU/L-OHP). Taking CRG5-FU/L-OHP as reference, we evaluated the clinical relevance of several types of genes derived from HCT116 CRC cells with resistance to 5-fluorouracil and oxaliplatin, respectively. The results revealed that DEGs between parental and resistant cells, when both were treated with the corresponding drug for a certain time, were significantly consistent with the CRG5-FU/L-OHP as well as the DEGs between the post-chemotherapy CRC specimens of responders and non-responders. This study suggests a novel strategy to extract clinically relevant drug resistance genes from both drug-induced resistant cell models and post-chemotherapy cancer tissue specimens.

  14. Resistance to RadLV-induced leukemia: non-participation of splenic natural killer cells

    International Nuclear Information System (INIS)

    St-Pierre, Y.; Hugo, P.; Lemieux, S.; Lussier, G.; Potworowski, E.F.

    1988-01-01

    The phenotypic expression of genetically determined resistance to radiation leukemia virus (RadLV)-induced leukemia in mice has been shown to reside in the bone marrow. Because the bone marrow contains precursors of natural killer (NK) cells, known to play a role in retrovirally induced infections, and because these cells have been suggested as participating in resistance to radiation-induced leukemia, it was pertinent to establish whether their levels differed in strains of mice susceptible and resistant to leukemia. We therefore tested splenic NK cell levels in C57BL/Ka (susceptible) and B10.A(5R) (resistant) mice before viral inoculation, immediately after viral inoculation, and throughout the preleukemic period and showed that they were not different. This indicates that splenic NK cell levels have no bearing on the resistance to RadLV-induced leukemia and that other immune or non-immune mechanisms must be sought

  15. Abiotic stresses affect Trichoderma harzianum T39-induced resistance to downy mildew in grapevine.

    Science.gov (United States)

    Roatti, Benedetta; Perazzolli, Michele; Gessler, Cesare; Pertot, Ilaria

    2013-12-01

    Enhancement of plant defense through the application of resistance inducers seems a promising alternative to chemical fungicides for controlling crop diseases but the efficacy can be affected by abiotic factors in the field. Plants respond to abiotic stresses with hormonal signals that may interfere with the mechanisms of induced systemic resistance (ISR) to pathogens. In this study, we exposed grapevines to heat, drought, or both to investigate the effects of abiotic stresses on grapevine resistance induced by Trichoderma harzianum T39 (T39) to downy mildew. Whereas the efficacy of T39-induced resistance was not affected by exposure to heat or drought, it was significantly reduced by combined abiotic stresses. Decrease of leaf water potential and upregulation of heat-stress markers confirmed that plants reacted to abiotic stresses. Basal expression of defense-related genes and their upregulation during T39-induced resistance were attenuated by abiotic stresses, in agreement with the reduced efficacy of T39. The evidence reported here suggests that exposure of crops to abiotic stress should be carefully considered to optimize the use of resistance inducers, especially in view of future global climate changes. Expression analysis of ISR marker genes could be helpful to identify when plants are responding to abiotic stresses, in order to optimize treatments with resistance inducers in field.

  16. Advances in induced resistance by natural compounds: towards new options for woody crop protection

    Directory of Open Access Journals (Sweden)

    Eugenio Llorens

    Full Text Available ABSTRACT: The activation of defensive responses of plants is a promising tool for controlling pests in conventional agriculture. Over the last few years, several compounds have been studied to protect crops from pests, without displaying direct toxicity for pathogenic organisms. These compounds have the ability to induce a priming state on the plants that results in resistance (or tolerance against subsequent infection by a pathogen. In terms of molecular response, induced plant defense involves a broad number of physical and biochemical changes such as callose deposition or phenolic compounds, activation of salicylic and/or jasmonic acid pathways or synthesis of defense-related enzymes. Despite the large number of studies performed to ascertain the physiological and biochemical basis of induced resistance, only a few resistance-activating compounds have been studied as a real alternative to classic means of control and the studies geared towards incorporating induced resistance into disease management programs are relatively rare. The incorporation of natural resistance inducer in pest management programs of woody crops, alone or in combination with classical methods, could be a reliable method for reducing the amount of chemical residues in the environment. In this review, we discuss the current knowledge of induced resistance in woody crops, focusing on the mode of action of compounds authorized for conventional agriculture. We conclude by discussing the environmental and economic advantages of applying resistance inducers to conventional agriculture with special emphasis on natural compounds.

  17. Three-dimensional induced polarization data inversion for complex resistivity

    Energy Technology Data Exchange (ETDEWEB)

    Commer, M.; Newman, G.A.; Williams, K.H.; Hubbard, S.S.

    2011-03-15

    The conductive and capacitive material properties of the subsurface can be quantified through the frequency-dependent complex resistivity. However, the routine three-dimensional (3D) interpretation of voluminous induced polarization (IP) data sets still poses a challenge due to large computational demands and solution nonuniqueness. We have developed a flexible methodology for 3D (spectral) IP data inversion. Our inversion algorithm is adapted from a frequency-domain electromagnetic (EM) inversion method primarily developed for large-scale hydrocarbon and geothermal energy exploration purposes. The method has proven to be efficient by implementing the nonlinear conjugate gradient method with hierarchical parallelism and by using an optimal finite-difference forward modeling mesh design scheme. The method allows for a large range of survey scales, providing a tool for both exploration and environmental applications. We experimented with an image focusing technique to improve the poor depth resolution of surface data sets with small survey spreads. The algorithm's underlying forward modeling operator properly accounts for EM coupling effects; thus, traditionally used EM coupling correction procedures are not needed. The methodology was applied to both synthetic and field data. We tested the benefit of directly inverting EM coupling contaminated data using a synthetic large-scale exploration data set. Afterward, we further tested the monitoring capability of our method by inverting time-lapse data from an environmental remediation experiment near Rifle, Colorado. Similar trends observed in both our solution and another 2D inversion were in accordance with previous findings about the IP effects due to subsurface microbial activity.

  18. STX140, but not paclitaxel, inhibits mammary tumour initiation and progression in C3(1/SV40 T/t-antigen transgenic mice.

    Directory of Open Access Journals (Sweden)

    Florence Meyer-Losic

    Full Text Available Despite paclitxael's clinical success, treating hormone-refractory breast cancer remains challenging. Paclitaxel has a poor pharmacological profile, characterized by a low therapeutic index (TIX caused by severe dose limiting toxicities, such as neutropenia and peripheral neuropathy. Consequently, new drugs are urgently required. STX140, a compound previously shown to have excellent efficacy against many tumors, is here compared to paclitaxel in three translational in vivo breast cancer models, a rat model of peripheral neuropathy, and through pharmacological testing. Three different in vivo mouse models of breast cancer were used; the metastatic 4T1 orthotopic model, the C3(1/SV40 T-Ag model, and the MDA-MB-231 xenograft model. To determine TIX and pharmacological profile of STX140, a comprehensive dosing regime was performed in mice bearing MDA-MD-231 xenografts. Finally, peripheral neuropathy was examined using a rat plantar thermal hyperalgesia model. In the 4T1 metastatic model, STX140 and paclitaxel significantly inhibited primary tumor growth and lung metastases. All C3(1/SV40 T-Ag mice in the control and paclitaxel treated groups developed palpable mammary cancer. STX140 blocked 47% of tumors developing and significantly inhibited growth of tumors that did develop. STX140 treatment caused a significant (P<0.001 survival advantage for animals in early and late intervention groups. Conversely, in C3(1/SV40 T-Ag mice, paclitaxel failed to inhibit tumor growth and did not increase survival time. Furthermore, paclitaxel, but not STX140, induced significant peripheral neuropathy and neutropenia. These results show that STX140 has a greater anti-cancer efficacy, TIX, and reduced neurotoxicity compared to paclitaxel in C3(1/SV40 T-Ag mice and therefore may be of significant benefit to patients with breast cancer.

  19. Novel Mad2-targeting miR-493-3p controls mitotic fidelity and cancer cells' sensitivity to paclitaxel.

    Science.gov (United States)

    Tambe, Mahesh; Pruikkonen, Sofia; Mäki-Jouppila, Jenni; Chen, Ping; Elgaaen, Bente Vilming; Straume, Anne Hege; Huhtinen, Kaisa; Cárpen, Olli; Lønning, Per Eystein; Davidson, Ben; Hautaniemi, Sampsa; Kallio, Marko J

    2016-03-15

    The molecular pathways that contribute to the proliferation and drug response of cancer cells are highly complex and currently insufficiently characterized. We have identified a previously unknown microRNA-based mechanism that provides cancer cells means to stimulate tumorigenesis via increased genomic instability and, at the same time, evade the action of clinically utilized microtubule drugs. We demonstrate miR-493-3p to be a novel negative regulator of mitotic arrest deficient-2 (MAD2), an essential component of the spindle assembly checkpoint that monitors the fidelity of chromosome segregation. The microRNA targets the 3' UTR of Mad2 mRNA thereby preventing translation of the Mad2 protein. In cancer cells, overexpression of miR-493-3p induced a premature mitotic exit that led to increased frequency of aneuploidy and cellular senescence in the progeny cells. Importantly, excess of the miR-493-3p conferred resistance of cancer cells to microtubule drugs. In human neoplasms, miR-493-3p and Mad2 expression alterations correlated with advanced ovarian cancer forms and high miR-493-3p levels were associated with reduced survival of ovarian and breast cancer patients with aggressive tumors, especially in the paclitaxel therapy arm. Our results suggest that intratumoral profiling of miR-493-3p and Mad2 levels can have diagnostic value in predicting the efficacy of taxane chemotherapy.

  20. Induced mutations in cucumber for resistance to nematodes (Meloidogyne spp.)

    International Nuclear Information System (INIS)

    Udalov, V.B.; Prikhod'ko, V.F.

    1989-01-01

    Full text: Seeds were treated with EI and selection was carried out over 5 years. In the susceptible cv. ''M15'' treated with 0.05% EI for 21 h 7.6% of plants were found resistant, 72% only slightly susceptible. Mutants were used in crosses and hybrids showed 57-89% resistance over 6 generations. (author)

  1. Studies on induced resistance to blast in rice

    International Nuclear Information System (INIS)

    Zhang Mingxian

    1985-01-01

    Eleven rice varieties were treated with 60 Co gamma ray, laser and other mutagens. 154 mutants with different characters were developed. 154 mutants and their parents have been inoculated with blast (Piricularia oryzae) races. It was found that the mutants of disease-resistance could be produced. The disease-resistant mutants with various better cheracters were selected. The frequencies of mutation in disease-resistance are different with different parental varieties. After inoculation with 13 blast physiological races, the results showed that the spectrum of resistance of mutants, other characters were changed, when one character was changed. In order to get a veriety with higher yield and disease-resistance, it is important to take account of other economic charaters

  2. Novel free paclitaxel-loaded poly(L-γ-glutamylglutamine–paclitaxel nanoparticles

    Directory of Open Access Journals (Sweden)

    Danbo Yang

    2011-01-01

    Full Text Available Danbo Yang1, Sang Van2, Xinguo Jiang3, Lei Yu1,21Biomedical Engineering and Technology Institute, Institutes for Advanced Interdisciplinary Research, East China Normal University, Shanghai, People's Republic of China; 2Biomedical Group, Nitto Denko Technical Corporation, Oceanside, CA, USA; 3School of Pharmacy, Fudan University, Shanghai, People's Republic of ChinaAbstract: The purpose of this study was to develop a novel formulation of paclitaxel (PTX that would improve its therapeutic index. Here, we combined a concept of polymer–PTX drug conjugate with a concept of polymeric micelle drug delivery to form novel free PTX-loaded poly(L-γ-glutamylglutamine (PGG–PTX conjugate nanoparticles. The significance of this drug formulation emphasizes the simplicity, novelty, and flexibility of the method of forming nanoparticles that contain free PTX and conjugated PTX in the same drug delivery system. The results of effectively inhibiting tumor growth in mouse models demonstrated the feasibility of the nanoparticle formulation. The versatility and potential of this dual PTX drug delivery system can be explored with different drugs for different indications. Novel and simple formulations of PTX-loaded PGG–PTX nanoparticles could have important implications in translational medicines.Keywords: paclitaxel, polymeric micelle, poly(L-γ-glutamylglutamine–paclitaxel, nanoconjugate, nanoparticles

  3. Resistance to ursodeoxycholic acid-induced growth arrest can also result in resistance to deoxycholic acid-induced apoptosis and increased tumorgenicity

    International Nuclear Information System (INIS)

    Powell, Ashley A; Akare, Sandeep; Qi, Wenqing; Herzer, Pascal; Jean-Louis, Samira; Feldman, Rebecca A; Martinez, Jesse D

    2006-01-01

    There is a large body of evidence which suggests that bile acids increase the risk of colon cancer and act as tumor promoters, however, the mechanism(s) of bile acids mediated tumorigenesis is not clear. Previously we showed that deoxycholic acid (DCA), a tumorogenic bile acid, and ursodeoxycholic acid (UDCA), a putative chemopreventive agent, exhibited distinct biological effects, yet appeared to act on some of the same signaling molecules. The present study was carried out to determine whether there is overlap in signaling pathways activated by tumorogenic bile acid DCA and chemopreventive bile acid UDCA. To determine whether there was an overlap in activation of signaling pathways by DCA and UDCA, we mutagenized HCT116 cells and then isolated cell lines resistant to UDCA induced growth arrest. These lines were then tested for their response to DCA induced apoptosis. We found that a majority of the cell lines resistant to UDCA-induced growth arrest were also resistant to DCA-induced apoptosis, implying an overlap in DCA and UDCA mediated signaling. Moreover, the cell lines which were the most resistant to DCA-induced apoptosis also exhibited a greater capacity for anchorage independent growth. We conclude that UDCA and DCA have overlapping signaling activities and that disregulation of these pathways can lead to a more advanced neoplastic phenotype

  4. Cetuximab-Induced MET Activation Acts as a Novel Resistance Mechanism in Colon Cancer Cells

    Directory of Open Access Journals (Sweden)

    Na Song

    2014-04-01

    Full Text Available Aberrant MET expression and hepatocyte growth factor (HGF signaling are implicated in promoting resistance to targeted agents; however, the induced MET activation by epidermal growth factor receptor (EGFR inhibitors mediating resistance to targeted therapy remains elusive. In this study, we identified that cetuximab-induced MET activation contributed to cetuximab resistance in Caco-2 colon cancer cells. MET inhibition or knockdown sensitized Caco-2 cells to cetuximab-mediated growth inhibition. Additionally, SRC activation promoted cetuximab resistance by interacting with MET. Pretreatment with SRC inhibitors abolished cetuximab-mediated MET activation and rendered Caco-2 cells sensitive to cetuximab. Notably, cetuximab induced MET/SRC/EGFR complex formation. MET inhibitor or SRC inhibitor suppressed phosphorylation of MET and SRC in the complex, and MET inhibitor singly led to disruption of complex formation. These results implicate alternative targeting of MET or SRC as rational strategies for reversing cetuximab resistance in colon cancer.

  5. Production of paclitaxel by Fusarium solani isolated from Taxus ...

    Indian Academy of Sciences (India)

    SEARCH U

    The mobile phase ... 0.1% trifluoroacetic acid (TFA) at a flow rate of 1 ml/min and absorbance was monitored at 227 nm. ... Institute of Microbial Technology, Chandigarh, India. ... engineering may improve paclitaxel production by F. solani.

  6. Preparation and evaluation of peptide-dendrimer-paclitaxel ...

    African Journals Online (AJOL)

    Tropical Journal of Pharmaceutical Research April 2017; 16 (4): 737-742 ... conjugates for treatment of heterogeneous stage 1 non- small cell lung ... Keywords: Paclitaxel, Lung cancer, Non-small cell lung cancer, Dendrimer, Peptide, PAMAM.

  7. Surface Resistance Measurements and Estimate of the Beam-Induced Resistive Wall Heating of the LHC Dipole Beam Screen

    CERN Document Server

    Caspers, Friedhelm; Ruggiero, F; Tan, J

    1999-01-01

    An estimate of the resistive losses in the LHC beam screen is given from cold surface resistance measurements using the shielded pair technique, with particular emphasis on the effect of a high magnetic field. Two different copper coating methods, namely electro-deposition and co-lamination, have been evaluated. Experimental data are compared with theories including the anomalous skin effect and the magneto-resistance effect. It is shown whether the theory underestimates or not the losses depends strongly on the RRR value, on the magnetic field and on the surface characteristics. In the pessimistic case and for nominal machine parameters, the estimated beam-induced resistive wall heating can be as large as 260 mW/m for two circulating beams.

  8. Synthesis and characterization of a fluorescent water-soluble paclitaxel prodrug.

    Science.gov (United States)

    Sohn, Jeong-Sun; Choi, Eun-Sun; Jo, Byung-Wook; Hess, Michael; Han, Song-Hee

    2010-05-01

    A fluorescence susceptible water-soluble paclitaxel was synthesized by a condensation reaction between PEGylated paclitaxel (namely, PP7) and 1-pyrene butyric acid (PBA) in order to obtain a better understanding of the mechanism of action of paclitaxel as well as of the environment of the paclitaxel-binding site. The reaction was performed successfully and the resulting paclitaxel was characterized by FT-NMR, analytical-HPLC, UV spectro photometry, and fluorescence spectrometry. The synthesized paclitaxel analogue showed a high susceptibility to fluorescence in both excitation and emission spectra. And we have investigated the time-resolved fluorescence behavior of them in different solvents and at different excitation wavelengths.

  9. Induced mutations for resistance to powdery mildew in wheat

    International Nuclear Information System (INIS)

    Liu Xueyu

    1990-01-01

    The most serious diseases of wheat in the Yangtze River Valley in China are powdery mildew and scab. Breeding for disease resistance either using conventional methods or through mutation breeding is the best way of controlling these diseases. Mutation breeding may be valuable in obtaining genotypes with resistance or tolerance, or for breaking undesirable linkages involving existing genes for disease resistance. The following commercial varieties were used: Yangmai 3, Ningmai 3 and Ningmai 6. They are high-yielding varieties, but susceptible to powdery mildew. Seeds of these cultivars were treated with gamma-rays. The material was screened in the seedling stage in M 2 in the greenhouse and under field conditions in M 3 -M 4 and later generations. The seedlings were inoculated with a spore suspension of the powdery mildew fungus. The most resistant mutant selected from variety Ningmai 3 was the line 34080 with resistance to races 4, 16 and 20. According to the number of progenies in M 2 , the mutation frequency was 1.2x10 -4 . The other two mutants (34157, 34158) were screened from variety Yangmai 3. Mutant 34157 showed a stable resistance to races 4, 16 and 20; mutant 34158 was resistant to races 4 and 20 but susceptible to race 16. Tracing them back to M 2 progeny, the mutation frequency was 1.0x10 -4 . From electrophoretic analysis of mildew resistant mutant lines of wheat we found that the zymogram of peroxidase in resistant lines 34080 and 34157 was different from their parents and that these lines do not have band 3A

  10. Hypoxia-induced cytotoxic drug resistance in osteosarcoma is independent of HIF-1Alpha.

    Directory of Open Access Journals (Sweden)

    Jennifer Adamski

    Full Text Available Survival rates from childhood cancer have improved dramatically in the last 40 years, such that over 80% of children are now cured. However in certain subgroups, including metastatic osteosarcoma, survival has remained stubbornly poor, despite dose intensive multi-agent chemotherapy regimens, and new therapeutic approaches are needed. Hypoxia is common in adult solid tumours and is associated with treatment resistance and poorer outcome. Hypoxia induces chemotherapy resistance in paediatric tumours including neuroblastoma, rhabdomyosarcoma and Ewing's sarcoma, in vitro, and this drug resistance is dependent on the oxygen-regulated transcription factor hypoxia inducible factor-1 (HIF-1. In this study the effects of hypoxia on the response of the osteosarcoma cell lines 791T, HOS and U2OS to the clinically relevant cytotoxics cisplatin, doxorubicin and etoposide were evaluated. Significant hypoxia-induced resistance to all three agents was seen in all three cell lines and hypoxia significantly reduced drug-induced apoptosis. Hypoxia also attenuated drug-induced activation of p53 in the p53 wild-type U2OS osteosarcoma cells. Drug resistance was not induced by HIF-1α stabilisation in normoxia by cobalt chloride nor reversed by the suppression of HIF-1α in hypoxia by shRNAi, siRNA, dominant negative HIF or inhibition with the small molecule NSC-134754, strongly suggesting that hypoxia-induced drug resistance in osteosarcoma cells is independent of HIF-1α. Inhibition of the phosphoinositide 3-kinase (PI3K pathway using the inhibitor PI-103 did not reverse hypoxia-induced drug resistance, suggesting the hypoxic activation of Akt in osteosarcoma cells does not play a significant role in hypoxia-induced drug resistance. Targeting hypoxia is an exciting prospect to improve current anti-cancer therapy and combat drug resistance. Significant hypoxia-induced drug resistance in osteosarcoma cells highlights the potential importance of hypoxia as a target

  11. Stem and stripe rust resistance in wheat induced by gamma rays and thermal neutrons

    International Nuclear Information System (INIS)

    Skorda, E.A.

    1977-01-01

    Attempts were made to produce rust-resistant mutants in wheat cultivars. Seeds of G-38290 and G-58383 (T. aestivum), Methoni and Ilectra (T. durum) varieties were irradiated with different doses of γ-rays (3.5, 5, 8, 11, 15 and 21 krad) and thermal neutrons (1.7, 4, 5.5, 7.5, 10.5 and 12.5x10 12 ) and the M 1 plants were grown under isolation in the field. The objective was mainly to induce stripe, leaf and stem rust resistance in G-38290, Methoni and Ilectra varieties and leaf rust resistance in G-58383. Mutations for rust resistance were detected by using the ''chimera method'' under natural and artificial field epiphytotic conditions in M 2 and successive generations. The mutants detected were tested for resistance to a broad spectrum of available races. Mutants resistant or moderately resistant to stripe and stem rusts but not to leaf rust, were selected from G-38290. From the other three varieties tested no rust-resistant mutants were detected. The frequency of resistant mutants obtained increased with increased γ-ray dose-rate, but not with increased thermal neutron doses. Some mutants proved to be resistant or moderately resistant to both rusts and others to one of them. Twenty of these mutants were evaluated for yield from M 5 to M 8 . Some of them have reached the final stage of regional yield trials and one, induced by thermal neutrons, was released this year. (author)

  12. Induction of apoptosis and cell proliferation inhibition by paclitaxel in ...

    African Journals Online (AJOL)

    In this study, anti-proliferative and apoptotic effects of paclitaxel, which is itself an antichemotherapeutic agent, to FM3A cell line originated from Mouse mammary carcinoma at 7 different doses were examined. Seven different doses of paclitaxel (P1 = 3 nM, P2 = 7.5 nM, P3 = 15 nM, P4 = 30 nM, P5 = 60 nM, P6 = 120 nM, ...

  13. Alternaria resistance of Brassicae campestris L. improved by induced mutations

    International Nuclear Information System (INIS)

    Das, M.L.; Rahman, A.

    1989-01-01

    Full text: Seeds of 'YS 52', a cultivar susceptible to Alternaria brassicae (Berk.) Sacc., were exposed to gamma rays (30-90 kR). Eight more resistant mutants were selected in M3 and subjected to further field evaluation. The best mutant '17-5-83' appeared resistant and gave 44% higher yield than the parent, mutant '70-7-82' was found to be moderately resistant and gave a yield 21% higher than the parent. The yield increases seem to be connected with plant architecture changes. (author)

  14. Fentanyl Enhances Hepatotoxicity of Paclitaxel via Inhibition of CYP3A4 and ABCB1 Transport Activity in Mice

    Science.gov (United States)

    Pan, Jia-Hao; Bi, Bing-Tian; Feng, Kun-Yao; Huang, Wan; Zeng, Wei-An

    2015-01-01

    Fentanyl, a potent opioid analgesic that is used to treat cancer pain, is commonly administered with paclitaxel in advanced tumors. However, the effect of fentanyl on the hepatotoxicity of paclitaxel and its potential mechanism of action is not well studied. The purpose of this study was to investigate the effect of fentanyl on the hepatotoxicity of paclitaxel and its potential mechanisms of action. Pharmacokinetic parameters of paclitaxel were tested using reversed phase high-performance liquid chromatography (RP-HPLC). Aspartate transaminase (AST), alanine aminotransferase (ALT), and mouse liver histopathology were examined. Moreover, the cytotoxicity of anti-carcinogens was examined using 1-(4, 5-dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT), and the intracellular accumulation of doxorubicin and rhodamine 123 was detected by flow cytometry. Furthermore, the expression of ABCB1 and the activity of ABCB1 ATPase and CYP3A4 were also examined. In this study, the co-administration of fentanyl and paclitaxel prolonged the half-life (t1/2) of paclitaxel from 1.455 hours to 2.344 hours and decreased the clearance (CL) from 10.997 ml/h to 7.014 ml/h in mice. Fentanyl significantly increased the levels of ALT in mice to 88.2 U/L, which is more than 2-fold higher than the level detected in the control group, and it increased the histological damage in mouse livers. Furthermore, fentanyl enhanced the cytotoxicity of anti-carcinogens that are ABCB1 substrates and increased the accumulation of doxorubicin and rhodamine 123. Additionally, fentanyl stimulated ABCB1 ATPase activity and inhibited CYP3A4 activity in the liver microsomes of mice. Our study indicates that the obvious hepatotoxicity during this co-administration was due to the inhibition of CYP3A4 activity and ABCB1 transport activity. These findings suggested that the accumulation-induced hepatotoxicity of paclitaxel when it is combined with fentanyl should be avoided. PMID:26633878

  15. Randomized Phase II trial of paclitaxel plus valproic acid vs paclitaxel alone as second-line therapy for patients with advanced gastric cancer

    Directory of Open Access Journals (Sweden)

    Fushida S

    2015-04-01

    Full Text Available Sachio Fushida,1 Masahide Kaji,2 Katsunobu Oyama,1 Yasuo Hirono,3 Hideaki Nezuka,4 Toshiya Takeda,5 Tomoya Tsukada,1 Daisuke Fujimoto,3 Shigekazu Ohyama,6 Takashi Fujimura,7 Tetsuo Ohta1 On behalf of the Digestive Disease Support Organization (DDSO 1Department of Gastroenterological Surgery, Kanazawa University Hospital, Kanazawa, 2Department of Surgery, Toyama Prefectural Central Hospital, Toyama, 3First Department of Surgery, Fukui University Hospital, Fukui, 4Department of Surgery, Yatsuo General Hospital, Toyama, 5Department of Surgery, Ishikawa Matto Central Hospital, Hakusan, 6Department of Surgery, Kanazawa Medical Center, Kanazawa, 7Toyama City Hospital, Toyama, Japan Abstract: The standard regimen of second-line chemotherapy for patients with unresectable gastric cancer has not been established. However, weekly paclitaxel (wPTX has become the preferable second-line chemotherapy in Japan. Histone deacetylase (HDAC inhibitors have been shown to have antiproliferative activity through cell-cycle arrest, differentiation, and apoptosis in gastric cancer cells. One HDAC inhibitor, valproic acid (VPA, also inhibits tumor growth by inducing apoptosis, and enhances the efficacy of paclitaxel in a mouse xenograft model of gastric cancer. wPTX plus VPA as a second-line chemotherapy is expected to improve survival in gastric cancer patients. A multicenter randomized Phase II study was conducted to compare the effects of wPTX plus VPA and wPTX alone. A total of 66 patients participated in this study. The primary end point of the study was overall survival, and secondary end points were progression-free survival, response rate, and assessment of peripheral neuropathy. Keywords: valproic acid, paclitaxel, second-line therapy, advanced gastric cancer 

  16. Failure of Elevating Calcium Induces Oxidative Stress Tolerance and Imparts Cisplatin Resistance in Ovarian Cancer Cells

    OpenAIRE

    Ma, Liwei; Wang, Hongjun; Wang, Chunyan; Su, Jing; Xie, Qi; Xu, Lu; Yu, Yang; Liu, Shibing; Li, Songyan; Xu, Ye; Li, Zhixin

    2016-01-01

    Cisplatin is a commonly used chemotherapeutic drug, used for the treatment of malignant ovarian cancer, but acquired resistance limits its application. There is therefore an overwhelming need to understand the mechanism of cisplatin resistance in ovarian cancer, that is, ovarian cancer cells are insensitive to cisplatin treatment. Here, we show that failure of elevating calcium and oxidative stress tolerance play key roles in cisplatin resistance in ovarian cancer cell lines. Cisplatin induce...

  17. Novel Therapeutic Targets to Inhibit Tumor Microenvironment Induced Castration-Resistant Prostate Cancer

    Science.gov (United States)

    2017-12-01

    AWARD NUMBER: W81XWH-13-1-0163 TITLE: Novel Therapeutic Targets to Inhibit Tumor Microenvironment Induced Castration-resistant Prostate Cancer ...Prostate Cancer 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Feng Yang, Ph.D. 5d. PROJECT NUMBER 5e. TASK NUMBER E-Mail: fyang@bcm.edu...W81XWH-13-1-0163 " Novel Therapeutic Targets to Inhibit Tumor Microenvironment Induced Castration-resistant Prostate Cancer " Introduction AR signaling

  18. Hepatocyte Toll-like receptor 4 regulates obesity-induced inflammation and insulin resistance

    Science.gov (United States)

    Chronic low-grade inflammation is a hallmark of obesity and thought to contribute to the development of obesity-related insulin resistance. Toll-like receptor 4 (Tlr4) is a key mediator of pro-inflammatory responses. Mice lacking Tlr4s are protected from diet-induced insulin resistance and inflammat...

  19. Induced mutations to develop sources of resistance to rice blast, Pyricularia grisea Sacc

    International Nuclear Information System (INIS)

    Correa-Victoria, F.J.

    2001-01-01

    Rice blast caused by Pyricularia grisea is the most important disease limiting yields worldwide. The pathogen has many virulent forms or pathotypes, hence durable blast resistance is lacking. Studies on strategy to develop durable blast resistance based on defining the genetic structure of the population, using DNA-fingerprinting, and virulence diversity are described. This strategy is leading to the identification of resistance genes/sources against all isolates within a genetic family of the pathogen. Combinations of genes showing complementary resistance to different genetic families of the fungus exclude any compatible interaction with a blast isolate. Identification of complementary resistance genes is based on detecting those virulence factors whose combinations in individual isolates within the pathogen population have a frequency near zero. Identifying and combining resistance genes to which combinations of corresponding virulence genes are absent in the pathogen population should confer more durable resistance than that previously obtained. The use of induced mutations in the development of resistance was limited, since in most cases single gene changes were responsible for the induced resistance against all the pathogen population. The main objective here is to develop many mutants, each with a gene resistant to just one or a few families of the blast pathogen; and crossing them can accumulate the different resistance genes. A total of 201 Latin American commercial cultivars, including Cuban, Brazilian and Venezuelan were analyzed with different genetic families of the blast pathogen to identify potential sources of resistance to blast and identify complementary resistance sources. Characterization of the resistance of 37 mutants of the Colombian rice cultivar Oryzica 1 was conducted in collaboration with the INEA in Colombia. Results suggested that mutations for resistance to genetic families to which Oryzica 1 is susceptible were induced, although one

  20. A study of concurrent radiochemotherapy with paclitaxel in glioblastoma multiforme

    International Nuclear Information System (INIS)

    Julka, P.K.; Awasthy, B.S.; Rath, G.K.; Agarwal, S.; Varna, T.; Mahapatra, A.K.; Singh, R.

    2000-01-01

    Despite advances in neurosurgery and radiotherapy, the prognosis of patients with glioblastoma multiforme remains poor. Reports in the literature about the radiosensitizing properties of paclitaxel stimulated the authors to conduct a study using paclitaxel concurrently with radiation in a group of 18 patients who had residual disease postoperatively. Paclitaxel was delivered weekly as an intravenous infusion in a dose of 60 mg/m 2 along with radiation to the primary lesion. A total of 108 cycles of paclitaxel was given. All the patients tolerated the treatment well. The main side effects were haematological, and neuropathy which was self-limiting. The overall 1-year survival rate was 70%, with 12 patients alive at 13 months. The median survival has not yet been reached although it is more than 13 months. Thus, paclitaxel can be safely delivered concomitantly with radiation in patients with glioblastoma multiforme. Larger, randomized trials are required to establish the comparative efficacy of paclitaxel as a radiosensitizer in glioblastoma multiforme. Copyright (1999) Blackwell Science Pty Ltd

  1. Induced mutations in beans and peas for resistance to rust

    International Nuclear Information System (INIS)

    Fadl, F.A.M.

    1983-01-01

    Gamma rays and ethyl methanesulphonate (EMS) were applied in a mutation-induction programme for rust resistance in bean and pea. Bean and pea seeds were pre-soaked 2 hours before irradiation with 9, 10 and 12 krad. For chemical mutagen treatments bean and pea seeds were pre-soaked for 8 hours and treated with 0.5 and 1.5% EMS for four hours. M 2 seeds of beans and peas were planted in 1979. Resistant M 2 plants were selected for their rust resistance and other morphological characters. M 3 seeds of selected plants were planted in 1980. In 1980 more seeds of the same varieties of beans and peas were treated with 0.1 and 0.3% EMS with the aim to produce rust-resistant mutants. Seed germination was reduced by gamma rays or EMS. Dwarf, malformed and abnormal plants were noticed. Some resistant M 2 plants selected gave high grain yields. Some were different in morphological characters. In the M 3 of selected plants various other mutant characters appeared, such as different height of plants, early and late flowering, resistance to powdery mildew in peas, altered grain yield, thickness of stem, pod shape and flower colour. (author)

  2. Apoptotic effect of cordycepin combined with cisplatin and/or paclitaxel on MA-10 mouse Leydig tumor cells

    Directory of Open Access Journals (Sweden)

    Kang FC

    2015-09-01

    Full Text Available Fu-Chi Kang,1 Pei-Jung Chen,2 Bo-Syong Pan,2,3 Meng-Shao Lai,2,3 Yung-Chia Chen,4 Bu-Miin Huang2,31Department of Anesthesia, Chi Mei Medical Center, Chiali, 2Department of Cell Biology and Anatomy, 3Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, 4Department of Anatomy, School of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan, Republic of China Background: Chemotherapy is not limited to a single treatment, and the evidence demonstrates that different drug combinations can have positive results in patients. In this study, we sought to determine whether cordycepin combined with cisplatin and/or paclitaxel would have an additive effective on inducing apoptosis in mouse Leydig tumor cells, and the mechanisms were also briefly examined.Methods: The additive effects of cordycepin combined with cisplatin and/or paclitaxel on apoptosis in MA-10 cells were investigated by monitoring changes in morphological characteristics and examining cell viability, flow cytometry assays, and Western blot analyses.Results: Combination of cordycepin plus cisplatin and/or paclitaxel for 12 and 24 hours induced apoptotic features in MA-10 cells. The MTT assay showed that the combination treatment reduced the viability of MA-10 cells in a dose-dependent manner, with additive effects. Cell cycle analysis showed that combination treatment significantly increased subG1 phase cell numbers in MA-10 cells, indicating apoptosis. Moreover, cordycepin plus cisplatin and/or paclitaxel significantly induced cleavage of caspase-8, caspase-9, caspase-3, and poly ADP-ribose polymerase, and phosphorylation of c-Jun NH2-terminal kinase, extracellular signal-regulated kinase, p38, and p53 proteins in MA-10 cells.Conclusion: Cordycepin plus cisplatin and/or paclitaxel can have an additive effect on apoptosis in MA-10 cells, with activation of caspase, mitogen-activated protein kinase, and p53 signal pathways. Keywords: cordycepin

  3. N-(4-Hydroxyphenyl) retinamide potentiated paclitaxel for cell cycle arrest and apoptosis in glioblastoma C6 and RG2 cells

    OpenAIRE

    Janardhanan, Rajiv; Butler, Jonathan T.; Banik, Naren L.; Ray, Swapan K.

    2009-01-01

    Glioblastoma grows aggressively due to its ability to maintain abnormally high potentials for cell proliferation. The present study examines the synergistic actions of N-(4-hdroxyphenyl) retinamide (4-HPR) and paclitaxel (PTX) to control the growth of rat glioblastoma C6 and RG2 cell lines. 4-HPR induced astrocytic differentiation was accompanied by increased expression of the tight junction protein e-cadherin and sustained down regulation of Id2 (member of inhibitor of differentiation family...

  4. Induced mutations for disease resistance in wheat and barley

    International Nuclear Information System (INIS)

    Hanis, M.; Hanisova, A.; Knytl, V.; Cerny, J.; Benc, S.

    1977-01-01

    The induction of mutations in cultivars of wheat (Triticum aestivum), barley (Hordeum vulgare), and field beans (Phaseolus vulgaris) has been part of the breeding programme at the Plant Breeding Station at Stupice since 1960. A total of 26 cultivars or selections of winter wheat, 4 cultivars or selections of spring wheat, 2 cultivars of field beans, and 43 selections of spring barley have been treated since 1960. A total of 140 mutant lines of wheat and 37 mutant lines of barley with improved disease resistance of a race-specific type have been obtained. Several mutation programme derived cultivars have been registered in Czechoslovakia (''Diamant'', ''Ametyst'', ''Favorit'', ''Hana'', ''Rapid'', and ''Atlas'' in barley, and ''Alfa'' in field beans), but none of them is a mutation for disease resistance. A series of mutants have been used in crossing programmes. Approaches to improve the efficiency of mutation breeding for disease resistance are suggested. (author)

  5. Induced mutations for disease resistance in wheat and field beans

    International Nuclear Information System (INIS)

    Abdel-Hak, T.M.; Kamel, A.H.

    1976-01-01

    Wheat disease in Egypt is reviewed and results of mutation breeding by γ irradiation for disease resistance in wheat and field beans are described. Wheat mutants of the variety Giza 155 resistant to leaf rust, Giza 156 resistant to both leaf and yellow rusts, and Tosson with a reasonable level of combined resistance to the three rusts in addition to mutants of the tetraploid variety Dakar 52 with a good level of stem and yellow rust resistance are required. Their seeds were subjected to 10, 15 and 20 krad. Of 3000-3700 M 2 plants from each variety and dosage, 22 plants from both Giza 155 and Giza 156, although susceptible, showed a lower level of disease development. In 1975, M 3 families of these selected plants and 6000 plants from bulked material were grown from each variety and dosage at two locations. Simultaneously, an additional population consisting of 3000 mutagen-treated seeds was grown to have a reasonable chance of detecting mutants; 2 heads from each plant were harvested. These will be grown next season (1976) to make a population of 25,000-30,000 M 2 plants and screened to composite cultures of specific rusts. Vicia faba seeds of field bean varieties Giza 1, Giza 2 and Rebaya 40, equally susceptible to rust and chocolate spot, were subjected to 3, 5 and 7 krad of 60 Co gamma radiation and 800 M 1 plants were grown in 1972 per variety and dose. Up to this later growing season (M 3 ) no resistance was detected in M 3 plank

  6. Induced mutations for rust resistance in bread wheat

    International Nuclear Information System (INIS)

    Sawhney, R.N.

    1989-01-01

    Full text: Seeds of variety ''Lalbahadur'' were treated with 0.04% NMH. M 2 plants were inoculated with a mixture of pathotypes of each of the 3 Puccinia species (P. graminis, P. recondita, P. striiformis). Plants with simultaneous resistance to all 3 rusts were selected. Repeated testing in subsequent generations confirmed the resistance. The mutant lines are morphologically similar to the parent cultivar and therefore could be used as components of a multiline variety. Comparison of variety pattern against the Indian pathotypes of rusts suggests that the mutant genes are different from the ones known already in bread wheat. (author)

  7. Induced resistance in tomato by SAR activators during predisposing salinity stress

    Directory of Open Access Journals (Sweden)

    Matthew Francis Pye

    2013-05-01

    Full Text Available Plant activators are chemicals that induce disease resistance. The phytohormone salicylic acid (SA is a crucial signal for systemic acquired resistance (SAR, and SA-mediated resistance is a target of several commercial plant activators, including Actigard (1,2,3-benzothiadiazole-7-thiocarboxylic acid-s-methyl-ester, BTH and Tiadinil (N-(3-chloro-4-methylphenyl-4-methyl-1,2,3-thiadiazole-5-carboxamide, TDL. BTH and TDL were examined for their impact on abscisic acid (ABA-mediated, salt-induced disease predisposition in tomato seedlings. A brief episode of salt stress to roots significantly increased the severity of disease caused by Pseudomonas syringae pv. tomato (Pst and Phytophthora capsici relative to non-stressed plants. Root treatment with TDL induced resistance to Pst in leaves and provided protection in both non-stressed and salt-stressed seedlings in WT and highly susceptible NahG plants. Non-stressed and salt-stressed ABA-deficient sitiens mutants were highly resistant to Pst. Neither TDL nor BTH induced resistance to root infection by P. capsici, nor did they moderate the salt-induced increment in disease severity. Root treatment with these plant activators increased the levels of ABA in roots and shoots similar to levels observed in salt-stressed plants. The results indicate that SAR activators can protect tomato plants from bacterial speck disease under predisposing salt stress, and suggest that some SA-mediated defense responses function sufficiently in plants with elevated levels of ABA.

  8. Induced mutations for horizontal resistance. A model study using leaf rust resistance in wheat

    International Nuclear Information System (INIS)

    Chopra, V.L.; Sawhney, R.N.; Kumar, R.

    1983-01-01

    A mutant with seemingly non-specific resistance to leaf rust was obtained some time ago from the wheat variety Kharchia Local treated with NMH. This mutant is being studied genetically and in its disease reaction by laboratories in Australia, Canada and India in co-operation. The mutant showed a dominant inheritance of resistance in F 1 , but different segregation in F 2 and F 3 . This peculiar genetic behaviour has so far not been explained. (author)

  9. Prenylated Chalcone 2 Acts as an Antimitotic Agent and Enhances the Chemosensitivity of Tumor Cells to Paclitaxel

    Directory of Open Access Journals (Sweden)

    Joana Fonseca

    2016-07-01

    Full Text Available We previously reported that prenylated chalcone 2 (PC2, the O-prenyl derivative (2 of 2′-hydroxy-3,4,4′,5,6′-pentamethoxychalcone (1, induced cytotoxicity of tumor cells via disruption of p53-MDM2 interaction. However, the cellular changes through which PC2 exerts its cytotoxic activity and its antitumor potential, remain to be addressed. In the present work, we aimed to (i characterize the effect of PC2 on mitotic progression and the underlying mechanism; and to (ii explore this information to evaluate its ability to sensitize tumor cells to paclitaxel in a combination regimen. PC2 was able to arrest breast adenocarcinoma MCF-7 and non-small cell lung cancer NCI-H460 cells in mitosis. All mitosis-arrested cells showed collapsed mitotic spindles with randomly distributed chromosomes, and activated spindle assembly checkpoint. Live-cell imaging revealed that the compound induced a prolonged delay (up to 14 h in mitosis, culminating in massive cell death by blebbing. Importantly, PC2 in combination with paclitaxel enhanced the effect on cell growth inhibition as determined by cell viability and proliferation assays. Our findings demonstrate that the cytotoxicity induced by PC2 is mediated through antimitotic activity as a result of mitotic spindle damage. The enhancement effects of PC2 on chemosensitivity of cancer cells to paclitaxel encourage further validation of the clinical potential of this combination.

  10. Circumvention of camptothecin-induced resistance during the adaptive cellular stress response.

    Science.gov (United States)

    Tiligada, Ekaterini; Papamichael, Konstantinos; Vovou, Ioanna; Delitheos, Andreas

    2006-01-01

    Camptothecin-11 (CPT-11) induces the adaptive stress response in yeast, conferring resistance via not fully characterized mechanisms. This study aimed at exploring, pharmacologically, the mechanisms underlying the CPT-11-induced resistance in yeast. Post-logarithmic yeast cultures were submitted to heat shock following preconditioning with suramin and with CPT-11, either alone or in combination with suramin, cycloheximide, sodium molybdate, okadaic acid, or verapamil. The stress response was evaluated by determining cell viability after heat shock. Preconditioning with CPT-11 or suramin conferred thermotolerance to yeast cells. Co-administration of CPT-11 with suramin, cycloheximide or okadaic acid reversed the CPT-11-induced thermotolerant phenotype, while sodium molybdate and verapamil had no effect on CPT-11-induced resistance. The antagonistic effect of the thermotolerance-inducers and the possible contribution of topoisomerase II activity and post-translational modifications mediated by the phosphatases PP1/2A in CPT-11-induced resistance may have important implications on the acquisition of resistance to stress in eukaryotic cells.

  11. Alloxan-induced and Insulin-resistant Diabetes Mellitus affect ...

    African Journals Online (AJOL)

    The purpose of this study was to determine the effects of diabetes mellitus and insulin resistance on semen parameters, histology of reproductive organs and serum concentrations of testosterone and luteinizing hormone (LH). Male Sprague-Dawley rats weighing 180 - 200g were made diabetic by intravenous injection of ...

  12. Acibenzolar-S-methyl induces lettuce resistance against ...

    African Journals Online (AJOL)

    Jane

    2011-08-24

    Aug 24, 2011 ... Acibenzolar-S-methyl (Benzo [1,2,3] thiadiazole-7-carbothioic acid-S-methyl ester, ASM; Bion 50 WG) was found to ... compounds are frequently used, they have hazardous effect on ... resistance (SAR) is characterized by a reduction in the number of ... cellular defence responses such as synthesis of patho-.

  13. Assessing the oseltamivir-induced resistance risk and implications for influenza infection control strategies

    Directory of Open Access Journals (Sweden)

    Hsieh NH

    2017-07-01

    Full Text Available Nan-Hung Hsieh,1 Yi-Jun Lin,2 Ying-Fei Yang,2 Chung-Min Liao2 1Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA; 2Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, Taiwan Background: Oseltamivir-resistant mutants with higher drug resistance rates and low transmission fitness costs have not accounted for influenza (subtype viruses. Predicting the impacts of neuraminidase inhibitor therapy on infection rates and transmission of drug-resistant viral strains requires further investigation.Objectives: The purpose of this study was to assess the potential risk of oseltamivir-induced resistance for influenza A (H1N1 and A (H3N2 viruses.Materials and methods: An immune-response-based virus dynamic model was used to best fit the oseltamivir-resistant A (H1N1 and A (H3N2 infection data. A probabilistic risk assessment model was developed by incorporating branching process-derived probability distribution of resistance to estimate oseltamivir-induced resistance risk.Results: Mutation rate and sensitive strain number were key determinants in assessing resistance risk. By increasing immune response, antiviral efficacy, and fitness cost, the spread of resistant strains for A (H1N1 and A (H3N2 were greatly decreased. Probability of resistance depends most strongly on the sensitive strain number described by a Poisson model. Risk of oseltamivir-induced resistance increased with increasing the mutation rate for A (H1N1 only. The ≥50% of resistance risk induced by A (H1N1 and A (H3N2 sensitive infected cells were 0.4 (95% CI: 0.28–0.43 and 0.95 (95% CI 0.93–0.99 at a mutation rate of 10−6, respectively. Antiviral drugs must be administrated within 1–1.5 days for A (H1N1 and 2–2.5 days for A (H3N2 virus infections to limit viral production.Conclusion: Probabilistic risk assessment of antiviral drug-induced

  14. Effect of resistance feedback on spin torque-induced switching of nanomagnets

    International Nuclear Information System (INIS)

    Garzon, Samir; Webb, Richard A.; Covington, Mark; Kaka, Shehzaad; Crawford, Thomas M.

    2009-01-01

    In large magnetoresistance devices spin torque-induced changes in resistance can produce GHz current and voltage oscillations which can affect magnetization reversal. In addition, capacitive shunting in large resistance devices can further reduce the current, adversely affecting spin torque switching. Here, we simultaneously solve the Landau-Lifshitz-Gilbert equation with spin torque and the transmission line telegrapher's equations to study the effects of resistance feedback and capacitance on magnetization reversal of both spin valves and magnetic tunnel junctions. While for spin valves parallel (P) to anti-parallel (AP) switching is adversely affected by the resistance feedback due to saturation of the spin torque, in low resistance magnetic tunnel junctions P-AP switching is enhanced. We study the effect of resistance feedback on the switching time of magnetic tunnel junctions, and show that magnetization switching is only affected by capacitive shunting in the pF range.

  15. Albumin-bound paclitaxel in solid tumors: clinical development and future directions.

    Science.gov (United States)

    Kundranda, Madappa N; Niu, Jiaxin

    2015-01-01

    Albumin-bound paclitaxel (nab-paclitaxel) is a solvent-free formulation of paclitaxel that was initially developed more than a decade ago to overcome toxicities associated with the solvents used in the formulation of standard paclitaxel and to potentially improve efficacy. Nab-paclitaxel has demonstrated an advantage over solvent-based paclitaxel by being able to deliver a higher dose of paclitaxel to tumors and decrease the incidence of serious toxicities, including severe allergic reactions. To date, nab-paclitaxel has been indicated for the treatment of three solid tumors in the USA. It was first approved for the treatment of metastatic breast cancer in 2005, followed by locally advanced or metastatic non-small-cell lung cancer in 2012, and most recently for metastatic pancreatic cancer in 2013. Nab-paclitaxel is also under investigation for the treatment of a number of other solid tumors. This review highlights key clinical efficacy and safety outcomes of nab-paclitaxel in the solid tumors for which it is currently indicated, discusses ongoing trials that may provide new data for the expansion of nab-paclitaxel's indications into other solid tumors, and provides a clinical perspective on the use of nab-paclitaxel in practice.

  16. Uranium deposit interpretation based on resistivity and induced polarization data in Rabau hulu sector

    International Nuclear Information System (INIS)

    Dwi Haryanto; Bambang Soetopo; Adhika Junara Karunianto; Supriyanto

    2015-01-01

    Rabau Hulu area, Kalan, Kalimantan Barat is a potential area of uranium that has been explored in detail by various methods. Methods of resistivity and induced polarization can be applied in the exploration of uranium deposits in which its mineralization associated with sulphide minerals. Processing, analysis, and interpretation of resistivity and induced polarization data conducted in order to identify the distribution of uranium deposits and lithology of the rocks in the study area. Uranium deposits in the area Rabau Hulu is generally associated with sulphides, tourmaline and contained in favorable rocks. Symptoms of uranium mineralization encountered in other forms of irregular and uneven consists of uraninite, pyrite, chalcopyrite, pyrrhotite, molybdenite, and ilmenite minerals. Data acquisition using dipole-dipole configuration in an area of approximately 36 hectares, 46 lines along ± 425 m. Acquisition of induced polarization frequency domain data which the same points and lines with resistivity data. Data processing produces resistivity and metal factor values and subsequently made two-dimensional section. Determination of resistivity and induced polarization are done by correlated boreholes data with the results of data processing. Resistivity of uranium deposits zone worth less than 2,000 Ωm and the value of metal factor greater than 90 mho/m. Uranium deposit zone is expanding along with the depth. Uranium deposits distribution trending Southwestern-Northeast and shaped lens. (author)

  17. Lipid-induced insulin resistance does not impair insulin access to skeletal muscle

    Science.gov (United States)

    Richey, Joyce M.; Castro, Ana Valeria B.; Broussard, Josiane L.; Ionut, Viorica; Bergman, Richard N.

    2015-01-01

    Elevated plasma free fatty acids (FFA) induce insulin resistance in skeletal muscle. Previously, we have shown that experimental insulin resistance induced by lipid infusion prevents the dispersion of insulin through the muscle, and we hypothesized that this would lead to an impairment of insulin moving from the plasma to the muscle interstitium. Thus, we infused lipid into our anesthetized canine model and measured the appearance of insulin in the lymph as a means to sample muscle interstitium under hyperinsulinemic euglycemic clamp conditions. Although lipid infusion lowered the glucose infusion rate and induced both peripheral and hepatic insulin resistance, we were unable to detect an impairment of insulin access to the lymph. Interestingly, despite a significant, 10-fold increase in plasma FFA, we detected little to no increase in free fatty acids or triglycerides in the lymph after lipid infusion. Thus, we conclude that experimental insulin resistance induced by lipid infusion does not reduce insulin access to skeletal muscle under clamp conditions. This would suggest that the peripheral insulin resistance is likely due to reduced cellular sensitivity to insulin in this model, and yet we did not detect a change in the tissue microenvironment that could contribute to cellular insulin resistance. PMID:25852002

  18. In Utero Estrogen Exposure Increases Antiestrogen Resistance by Inducing EMT

    Science.gov (United States)

    2015-02-01

    currently unclear. Our recent preclinical study found that maternal exposure to excess estrogens during pregnancy increases the risk that AE resistance in...References: 1. Hilakivi-Clarke L, Clarke R, Onojafe I, Raygada M, Cho E, Lippman M. A maternal diet high in n-6-polyunsaturated fats alters mammary...the rate of obesity in this country (high fat diets resulting in elevated circulating estrogen levels), the prevelance of bisphenol A in our drinking

  19. Go-6976 Reverses Hyperglycemia-Induced Insulin Resistance Independently of cPKC Inhibition in Adipocytes

    Science.gov (United States)

    Robinson, Katherine A.; Hegyi, Krisztina; Hannun, Yusuf A.; Buse, Maria G.; Sethi, Jaswinder K.

    2014-01-01

    Chronic hyperglycemia induces insulin resistance by mechanisms that are incompletely understood. One model of hyperglycemia-induced insulin resistance involves chronic preincubation of adipocytes in the presence of high glucose and low insulin concentrations. We have previously shown that the mTOR complex 1 (mTORC1) plays a partial role in the development of insulin resistance in this model. Here, we demonstrate that treatment with Go-6976, a widely used “specific” inhibitor of cPKCs, alleviates hyperglycemia-induced insulin resistance. However, the effects of mTOR inhibitor, rapamycin and Go-6976 were not additive and only rapamycin restored impaired insulin-stimulated AKT activation. Although, PKCα, (but not –β) was abundantly expressed in these adipocytes, our studies indicate cPKCs do not play a major role in causing insulin-resistance in this model. There was no evidence of changes in the expression or phosphorylation of PKCα, and PKCα knock-down did not prevent the reduction of insulin-stimulated glucose transport. This was also consistent with lack of IRS-1 phosphorylation on Ser-24 in hyperglycemia-induced insulin-resistant adipocytes. Treatment with Go-6976 did inhibit a component of the mTORC1 pathway, as evidenced by decreased phosphorylation of S6 ribosomal protein. Raptor knock-down enhanced the effect of insulin on glucose transport in insulin resistant adipocytes. Go-6976 had the same effect in control cells, but was ineffective in cells with Raptor knock-down. Taken together these findings suggest that Go-6976 exerts its effect in alleviating hyperglycemia-induced insulin-resistance independently of cPKC inhibition and may target components of the mTORC1 signaling pathway. PMID:25330241

  20. A specialist root herbivore reduces plant resistance and uses an induced plant volatile to aggregate in a density dependent manner

    Science.gov (United States)

    1. Leaf-herbivore attack often triggers induced resistance in plants. However, certain specialist herbivores can also take advantage of the induced metabolic changes. In some cases, they even manipulate plant resistance, leading to a phenomenon called induced susceptibility. Compared to above-ground...

  1. The chemotherapeutic agent paclitaxel selectively impairs reversal learning while sparing prior learning, new learning and episodic memory.

    Science.gov (United States)

    Panoz-Brown, Danielle; Carey, Lawrence M; Smith, Alexandra E; Gentry, Meredith; Sluka, Christina M; Corbin, Hannah E; Wu, Jie-En; Hohmann, Andrea G; Crystal, Jonathon D

    2017-10-01

    Chemotherapy is widely used to treat patients with systemic cancer. The efficacy of cancer therapies is frequently undermined by adverse side effects that have a negative impact on the quality of life of cancer survivors. Cancer patients who receive chemotherapy often experience chemotherapy-induced cognitive impairment across a variety of domains including memory, learning, and attention. In the current study, the impact of paclitaxel, a taxane derived chemotherapeutic agent, on episodic memory, prior learning, new learning, and reversal learning were evaluated in rats. Neurogenesis was quantified post-treatment in the dentate gyrus of the same rats using immunostaining for 5-Bromo-2'-deoxyuridine (BrdU) and Ki67. Paclitaxel treatment selectively impaired reversal learning while sparing episodic memory, prior learning, and new learning. Furthermore, paclitaxel-treated rats showed decreases in markers of hippocampal cell proliferation, as measured by markers of cell proliferation assessed using immunostaining for Ki67 and BrdU. This work highlights the importance of using multiple measures of learning and memory to identify the pattern of impaired and spared aspects of chemotherapy-induced cognitive impairment. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Herbivore-induced resistance against microbial pathogens in Arabidopsis

    NARCIS (Netherlands)

    Vos, de M.; Zaanen, van W.; Koornneef, A.; Korzelius, J.P.; Dicke, M.; Loon, van L.C.; Pieterse, C.M.J.

    2006-01-01

    Caterpillars of the herbivore Pieris rapae stimulate the production of jasmonic acid (JA) and ethylene (ET) in Arabidopsis (Arabidopsis thaliana) and trigger a defense response that affects insect performance on systemic tissues. To investigate the spectrum of effectiveness of P. rapae-induced

  3. Herbivore-induced resistance against microbial pathogens in Arabidopsis

    NARCIS (Netherlands)

    Vos, M. de; Zaanen, W. van; Koornneef, A.; Korzelius, J.P.; Dicke, M.; Loon, L.C. van; Pieterse, C.M.J.

    2006-01-01

    Caterpillars of the herbivore Pieris rapae stimulate the production of jasmonic acid (JA) and ethylene (ET) in Arabidopsis (Arabidopsis thaliana) and trigger a defense response that affects insect performance on systemic tissues. To investigate the sspectrum of effectiveness of P. rapae-induced

  4. BDP-30, a systemic resistance inducer from Boerhaavia diffusa L ...

    Indian Academy of Sciences (India)

    2015-01-11

    Jan 11, 2015 ... exogenous application of chemicals such as salicylic acid or its synthetic ...... be able to induce a mobile signal that takes effect both at site of application, and ... thesis of its gene and expression in Escherichia coli. J. Biol.

  5. Induced Pluripotent Stem Cell-Derived Endothelial Cells in Insulin Resistance and Metabolic Syndrome.

    Science.gov (United States)

    Carcamo-Orive, Ivan; Huang, Ngan F; Quertermous, Thomas; Knowles, Joshua W

    2017-11-01

    Insulin resistance leads to a number of metabolic and cellular abnormalities including endothelial dysfunction that increase the risk of vascular disease. Although it has been particularly challenging to study the genetic determinants that predispose to abnormal function of the endothelium in insulin-resistant states, the possibility of deriving endothelial cells from induced pluripotent stem cells generated from individuals with detailed clinical phenotyping, including accurate measurements of insulin resistance accompanied by multilevel omic data (eg, genetic and genomic characterization), has opened new avenues to study this relationship. Unfortunately, several technical barriers have hampered these efforts. In the present review, we summarize the current status of induced pluripotent stem cell-derived endothelial cells for modeling endothelial dysfunction associated with insulin resistance and discuss the challenges to overcoming these limitations. © 2017 American Heart Association, Inc.

  6. Use of some chemical inducers to improve wheat resistance to Puccinia striiformis f. Sp. Tritici

    Directory of Open Access Journals (Sweden)

    Al-Maaroof Emad

    2014-01-01

    Full Text Available The effect of DL-β-aminobutyric acid (BABA, benzothiadiazole (BTH, indoleacetic acid (IAA and salicylic acid (SA on induced systemic resistance was investigated in moderately susceptible and susceptible wheat genotypes Tamuz-2 and AL-8/70 against Puccinia striiformis f. sp. tritici. Resistance was characterized by reduced infection of yellow rust disease (Yrd. Changes in peroxidase, phenylalanine ammonia-lyase activities and in total phenolic compound content demonstrated that the resistance to Puccinia striiformis can be induced by BABA, BTH, IAA and SA in these two wheat genotypes. Further studies are needed before a practical method using many analogue compounds, such as potassium phosphate and biotic agent for Yrd resistance in wheat is developed.

  7. Nab-paclitaxel for the treatment of breast cancer: efficacy, safety, and approval

    Directory of Open Access Journals (Sweden)

    Iwase H

    2011-07-01

    Full Text Available Yutaka Yamamoto1, Ichiro Kawano2, Hirotaka Iwase11Department of Breast and Endocrine Surgery, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan; 2Department of Surgery, Asahino General Hospital, Kumamoto, JapanAbstract: Nanoparticle albumin-bound paclitaxel (nab-paclitaxel is a novel formulation of paclitaxel that does not require solvents such as polyoxyethylated castor oil and ethanol. Use of these solvents has been associated with toxic response, including hypersensitivity reactions and prolonged sensory neuropathy, as well as a negative impact in relation to the therapeutic index of paclitaxel. nab-paclitaxel displays greater antitumor activity and less toxicity than solvent-base paclitaxel. In a phase I trial of single nab-paclitaxel, the maximum tolerated dose was 300 mg/m2 with the dose limiting toxicities being sensory neuropathy, stomatitis, and superficial keratopathy. In the metastatic setting, a pivotal comparative randomized phase III study demonstrated that nab-paclitaxel (at 260 mg/m2 over 30 minutes infusion without premedication every 3 weeks mediated a superior objective response rate and prolonged time to progression compared with solvent-based paclitaxel (at 175 mg/m2 over a 3-hour injection with standard premedication. The nab-paclitaxel-treated group showed a higher incidence of sensory neuropathy than the solvent-based paclitaxel group. However, these adverse side effects rapidly resolved after interruption of treatment and dose reduction. Weekly administration of nab-paclitaxel was also more active and displayed less toxicity compared with 100 mg/m2 docetaxel given triweekly. Nab-paclitaxel has already been approved in 42 countries for the treatment of metastatic breast cancer previously treated with anthracycline, based on confirmation of the efficacy and manageable toxicity in the metastatic setting. This review summarizes the most relevant knowledge on nab-paclitaxel for treating breast cancer

  8. Peroxisome proliferator-activated receptor-gamma agonists suppress tissue factor overexpression in rat balloon injury model with paclitaxel infusion.

    Directory of Open Access Journals (Sweden)

    Jun-Bean Park

    Full Text Available The role and underlying mechanisms of rosiglitazone, a peroxisome proliferator-activated receptor-gamma (PPAR-γ agonist, on myocardial infarction are poorly understood. We investigated the effects of this PPAR-γ agonist on the expression of tissue factor (TF, a primary molecule for thrombosis, and elucidated its underlying mechanisms. The PPAR-γ agonist inhibited TF expression in response to TNF-α in human umbilical vein endothelial cells, human monocytic leukemia cell line, and human umbilical arterial smooth muscle cells. The overexpression of TF was mediated by increased phosphorylation of mitogen-activated protein kinase (MAPK, which was blocked by the PPAR-γ agonist. The effective MAPK differed depending on each cell type. Luciferase and ChIP assays showed that transcription factor, activator protein-1 (AP-1, was a pivotal target of the PPAR-γ agonist to lower TF transcription. Intriguingly, two main drugs for drug-eluting stent, paclitaxel or rapamycin, significantly exaggerated thrombin-induced TF expression, which was also effectively blocked by the PPAR-γ agonist in all cell types. This PPAR-γ agonist did not impair TF pathway inhibitor (TFPI in three cell types. In rat balloon injury model (Sprague-Dawley rats, n = 10/group with continuous paclitaxel infusion, the PPAR-γ agonist attenuated TF expression by 70±5% (n = 4; P<0.0001 in injured vasculature. Taken together, rosiglitazone reduced TF expression in three critical cell types involved in vascular thrombus formation via MAPK and AP-1 inhibitions. Also, this PPAR-γ agonist reversed the paclitaxel-induced aggravation of TF expression, which suggests a possibility that the benefits might outweigh its risks in a group of patients with paclitaxel-eluting stent implanted.

  9. SOCS-1 deficiency does not prevent diet-induced insulin resistance

    DEFF Research Database (Denmark)

    Emanuelli, Brice; Macotela, Yazmin; Boucher, Jérémie

    2008-01-01

    Obesity is associated with inflammation and increased expression of suppressor of cytokine signaling (SOCS) proteins, which inhibit cytokine and insulin signaling. Thus, reducing SOCS expression could prevent the development of obesity-induced insulin resistance. Using SOCS-1 knockout mice, we...... investigated the contribution of SOCS-1 in the development of insulin resistance induced by a high-fat diet (HFD). SOCS-1 knockout mice on HFD gained 70% more weight, displayed a 2.3-fold increase in epididymal fat pads mass and increased hepatic lipid content. This was accompanied by increased mRNA expression...... of leptin and the macrophage marker CD68 in white adipose tissue and of SREBP1c and FAS in liver. HFD also induced hyperglycemia in SOCS-1 deficient mice with impairment of glucose and insulin tolerance tests. Thus, despite the role of SOCS proteins in obesity-related insulin resistance, SOCS-1 deficiency...

  10. GLUT4 and glycogen synthase are key players in bed rest-induced insulin resistance

    DEFF Research Database (Denmark)

    Biensø, Rasmus Sjørup; Jørgensen, Stine Ringholm; Kiilerich, Kristian

    2012-01-01

    To elucidate the molecular mechanisms behind physical inactivity-induced insulin resistance in skeletal muscle, 12 young, healthy male subjects completed 7 days of bed rest with vastus lateralis muscle biopsies obtained before and after. In six of the subjects, muscle biopsies were taken from both...... than before bed rest. This bed rest-induced insulin resistance occurred together with reduced muscle GLUT4, hexokinase II, protein kinase B/Akt1, and Akt2 protein level, and a tendency for reduced 3-hydroxyacyl-CoA dehydrogenase activity. The ability of insulin to phosphorylate Akt and activate....... The present findings demonstrate that physical inactivity-induced insulin resistance in muscle is associated with lower content/activity of key proteins in glucose transport/phosphorylation and storage....

  11. Novel and Reversible Mechanisms of Smoking-Induced Insulin Resistance in Humans

    OpenAIRE

    Bergman, Bryan C.; Perreault, Leigh; Hunerdosse, Devon; Kerege, Anna; Playdon, Mary; Samek, Ali M.; Eckel, Robert H.

    2012-01-01

    Smoking is the most common cause of preventable morbidity and mortality in the United States, in part because it is an independent risk factor for the development of insulin resistance and type 2 diabetes. However, mechanisms responsible for smoking-induced insulin resistance are unclear. In this study, we found smokers were less insulin sensitive compared with controls, which increased after either 1 or 2 weeks of smoking cessation. Improvements in insulin sensitivity after smoking cessation...

  12. 11beta-hydroxysteroid dehydrogenase type 1 regulates glucocorticoid-induced insulin resistance in skeletal muscle.

    LENUS (Irish Health Repository)

    Morgan, Stuart A

    2009-11-01

    Glucocorticoid excess is characterized by increased adiposity, skeletal myopathy, and insulin resistance, but the precise molecular mechanisms are unknown. Within skeletal muscle, 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) converts cortisone (11-dehydrocorticosterone in rodents) to active cortisol (corticosterone in rodents). We aimed to determine the mechanisms underpinning glucocorticoid-induced insulin resistance in skeletal muscle and indentify how 11beta-HSD1 inhibitors improve insulin sensitivity.

  13. Chemotherapy-related amenorrhea after adjuvant paclitaxel-trastuzumab (APT trial).

    Science.gov (United States)

    Ruddy, Kathryn J; Guo, Hao; Barry, William; Dang, Chau T; Yardley, Denise A; Moy, Beverly; Marcom, P Kelly; Albain, Kathy S; Rugo, Hope S; Ellis, Matthew J; Shapira, Iuliana; Wolff, Antonio C; Carey, Lisa A; Overmoyer, Beth A; Hudis, Clifford; Krop, Ian E; Burstein, Harold J; Winer, Eric P; Partridge, Ann H; Tolaney, Sara M

    2015-06-01

    Chemotherapy-related amenorrhea (CRA) is associated with infertility and menopausal symptoms. Learning how frequently paclitaxel and trastuzumab cause amenorrhea is important. Most other adjuvant breast cancer therapies induce CRA in approximately 50 % of all premenopausal recipients [1]. 410 patients enrolled on the APT Trial, a single-arm phase 2 adjuvant study of 12 weeks of paclitaxel and trastuzumab followed by nine months of trastuzumab monotherapy. Eligible patients had ≤3 cm node-negative HER2 + breast cancers. Premenopausal enrollees were asked to complete menstrual surveys every 3-12 months for 72 months. Women who responded to at least one survey at least 15 months after chemotherapy initiation (and who did not undergo hysterectomy and/or bilateral oophorectomy or receive ovarian suppressing medications prior to 15 months) were included in this analysis. A participant was defined as having amenorrhea in follow-up if her self-reported last menstrual period at last follow-up was greater than 12 months prior to the survey. Among the 64 women in the evaluable population (median age at study entry 44 years, range 27-52 years), the median time between chemotherapy initiation and last menstrual survey was 51 months (range 16-79). 18 of 64 women (28 %, 95 % CI 18-41 %) were amenorrheic at that time point. Amenorrhea rates among premenopausal women treated with adjuvant paclitaxel and trastuzumab for early stage breast cancer appear lower than those seen historically with standard alkylator-based breast cancer regimens. Future studies are needed to understand the impact of this regimen on related issues of fertility and menopausal symptoms.

  14. Weekly dose-dense paclitaxel and carboplatin in recurrent ovarian carcinoma: A phase II trial

    International Nuclear Information System (INIS)

    Shawky, H.; Tawfik, H.; Hewidy, M.

    2014-01-01

    Purpose: The aim of this study was to investigate efficacy and toxicity of the dose-dense weekly paclitaxel (T) and carboplatin (C) in the management of platinum-resistant/sensitive recurrent epithelial ovarian cancer (EOC) previously treated with 3 weekly paclitaxel/carboplatin. Methods: Thirty two patients with recurrent EOC who had received 3 weekly TC before were enrolled. Nine patients relapsed within 6 months (platinum-resistant), 13 patients relapsed after 12 months (platinum-sensitive) and in 10 patients recurrence occurred between 6 and 12 months (intermediate platinum-sensitive). Weekly (T) at a dose of 80 mg/m2, followed by weekly (C) AUC 2 on day 1, 8, and 15 of a 28-day cycle for 6 planned cycles were administrated. End-points were overall response rate (ORR), progression free survival (PFS), overall survival (OS) and toxicity. Results: The ORR was 62.5%. For the platinum-resistant, intermediate platinum-sensitive and platinum-sensitive patients the ORR was 44.4% (4/9), 60% (6/10) and 76.9% (10/13), respectively, and 1 (11.1%), 2 (20%) and 5 (38.46%) patients, respectively had CR. PFS was 9.1 months (6.13, 9.1 and 12.17 months, for the 3 groups, respectively) (P < 0.001). OS was 14 months (9.17, 15.2, and 19.23 months, for the 3 groups, respectively) (P < 0.001). Treatment-related adverse events were manageable with only 1 patient (3.1%) suffering from grade 4 neutropenia. Grade 3 hematological and non-hematological toxicities were neutropenia in 8 (25%), and peripheral neuropathy in 4 (12.5%) patients, respectively. Conclusion: Weekly TC is active and well-tolerated in platinum-resistant and platinum-sensitive patients with recurrent EOC previously treated with TC given every 3 weeks

  15. Vitamin C deficiency aggravates tumor necrosis factor α-induced insulin resistance.

    Science.gov (United States)

    Qing, Zhou; Xiao-Hui, Wu; Xi-Mei, Wu; Chao-Chun, Zou

    2018-06-15

    Chronic low-grade inflammation plays a major role in the development of insulin resistance. The potential role and underlying mechanism of vitamin C, an antioxidant and anti-inflammatory agent, was investigated in tumor necrosis factor-α (TNF-α)-induced insulin resistance. Gulonolactone oxidase knockout (Gulo -/- ) mice genetically unable to synthesize vitamin C were used to induce insulin resistance by continuously pumping small doses of TNF-α for seven days, and human liver hepatocellular carcinoma cells (HepG2 cells) were used to induce insulin resistance by treatment with TNF-α. Vitamin C deficiency aggravated TNF-α-induced insulin resistance in Gulo -/- mice, resulting in worse glucose tolerance test (GTT) results, higher fasting plasma insulin level, and the inactivation of the protein kinase B (AKT)/glycogen synthase kinase-3β (GSK3β) pathway in the liver. Vitamin C deficiency also worsened liver lipid accumulation and inflammation in TNF-α-treated Gulo -/- mice. In HepG2 cells, vitamin C reversed the TNF-α-induced reduction of glucose uptake and glycogen synthesis, which were mediated by increasing GLUT2 levels and the activation of the insulin receptor substrate (IRS-1)/AKT/GSK3β pathway. Furthermore, vitamin C inhibited the TNF-α-induced activation of not only the mitogen-activated protein kinase (MAPKs), but also nuclear factor-kappa B (NF-κB) signaling. Taken together, vitamin C is essential for preventing and improving insulin resistance, and the supplementing with vitamin C may be an effective therapeutic intervention for metabolic disorders. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. A human model of dietary saturated fatty acid induced insulin resistance.

    Science.gov (United States)

    Koska, Juraj; Ozias, Marlies K; Deer, James; Kurtz, Julie; Salbe, Arline D; Harman, S Mitchell; Reaven, Peter D

    2016-11-01

    Increased consumption of high-fat diets is associated with the development of insulin resistance and type 2 diabetes. Current models to study the mechanisms of high-fat diet-induced IR in humans are limited by their long duration or low efficacy. In the present study we developed and characterized an acute dietary model of saturated fatty acid-enriched diet induced insulin resistance. High caloric diets enriched with saturated fatty acids (SFA) or carbohydrates (CARB) were evaluated in subjects with normal and impaired glucose tolerance (NGT or IGT). Both diets were compared to a standard eucaloric American Heart Association (AHA) control diet in a series of crossover studies. Whole body insulin resistance was estimated as steady state plasma glucose (SSPG) concentrations during the last 30min of a 3-h insulin suppression test. SSPG was increased after a 24-h SFA diet (by 83±74% vs. control, n=38) in the entire cohort, which was comprised of participants with NGT (92±82%, n=22) or IGT (65±55%, n=16) (all pinsulin resistance in both NGT and IGT subjects. Insulin resistance persisted overnight after the last SFA meal and was attenuated by one day of a healthy diet. This model offers opportunities for identifying early mechanisms and potential treatments of dietary saturated fat induced insulin resistance. Published by Elsevier Inc.

  17. Blast resistance of space-induced variants derived from rice cultivar Hanghui 7

    International Nuclear Information System (INIS)

    Zhang Jingxin; Yang Qiyun; Zhu Xiaoyuan; Wang Hui; Zeng Liexian; Liu Yongzhu; Guo Tao; Chen Zhiqiang

    2010-01-01

    To screen the resistance lines to rice blast, the blast resistance of SP 3 and SP 4 progenies derived from rice variety Hanghui 7 were evaluated after satellite flight, and the genomic DNA polymorphism of the resistant variants selected from SP 3 was compared with the wild type by microsatellite markers. The results indicated that the SP 3 Variant line H24, which was selected from the 250 space-induced lines ( SP 3 ) with excellent agronomic and economical characters, showed resistance segregation (119R : 108S) against blast isolate GD3286. It was demonstrated that the resistance of H24 might be controlled by two dominant and complementary resistance genes. The resistance of H24 was still segregated in SP 4 , but the resistance spectrum of H24 was 84. 4% in SP 5 , much higher than the wild type, 40. 6%, and H24 especially showed resistant against some blast isolates of broad pathogenic spectrum or specialized pathogenicity; further more, the DNA polymorphism wasn't detected between H24 and its wild type by 229 SSR (simple sequence repeat) markers covering the rice genome equally. (authors)

  18. Predictive and prognostic impact of TP53 mutations and MDM2 promoter genotype in primary breast cancer patients treated with epirubicin or paclitaxel.

    Directory of Open Access Journals (Sweden)

    Ranjan Chrisanthar

    Full Text Available BACKGROUND: TP53 mutations have been associated with resistance to anthracyclines but not to taxanes in breast cancer patients. The MDM2 promoter single nucleotide polymorphism (SNP T309G increases MDM2 activity and may reduce wild-type p53 protein activity. Here, we explored the predictive and prognostic value of TP53 and CHEK2 mutation status together with MDM2 SNP309 genotype in stage III breast cancer patients receiving paclitaxel or epirubicin monotherapy. EXPERIMENTAL DESIGN: Each patient was randomly assigned to treatment with epirubicin 90 mg/m(2 (n = 109 or paclitaxel 200 mg/m(2 (n = 114 every 3rd week as monotherapy for 4-6 cycles. Patients obtaining a suboptimal response on first-line treatment requiring further chemotherapy received the opposite regimen. Time from last patient inclusion to follow-up censoring was 69 months. Each patient had snap-frozen tumor tissue specimens collected prior to commencing chemotherapy. PRINCIPAL FINDINGS: While TP53 and CHEK2 mutations predicted resistance to epirubicin, MDM2 status did not. Neither TP53/CHEK2 mutations nor MDM2 status was associated with paclitaxel response. Remarkably, TP53 mutations (p = 0.007 but also MDM2 309TG/GG genotype status (p = 0.012 were associated with a poor disease-specific survival among patients having paclitaxel but not patients having epirubicin first-line. The effect of MDM2 status was observed among individuals harbouring wild-type TP53 (p = 0.039 but not among individuals with TP53 mutated tumors (p>0.5. CONCLUSION: TP53 and CHEK2 mutations were associated with lack of response to epirubicin monotherapy. In contrast, TP53 mutations and MDM2 309G allele status conferred poor disease-specific survival among patients treated with primary paclitaxel but not epirubicin monotherapy.

  19. Bias voltage induced resistance switching effect in single-molecule magnets' tunneling junction.

    Science.gov (United States)

    Zhang, Zhengzhong; Jiang, Liang

    2014-09-12

    An electric-pulse-induced reversible resistance change effect in a molecular magnetic tunneling junction, consisting of a single-molecule magnet (SMM) sandwiched in one nonmagnetic and one ferromagnetic electrode, is theoretically investigated. By applying a time-varying bias voltage, the SMM's spin orientation can be manipulated with large bias voltage pulses. Moreover, the different magnetic configuration at high-resistance/low-resistance states can be 'read out' by utilizing relative low bias voltage. This device scheme can be implemented with current technologies (Khajetoorians et al 2013 Science 339 55) and has potential application in molecular spintronics and high-density nonvolatile memory devices.

  20. Bias voltage induced resistance switching effect in single-molecule magnets’ tunneling junction

    Science.gov (United States)

    Zhang, Zhengzhong; Jiang, Liang

    2014-09-01

    An electric-pulse-induced reversible resistance change effect in a molecular magnetic tunneling junction, consisting of a single-molecule magnet (SMM) sandwiched in one nonmagnetic and one ferromagnetic electrode, is theoretically investigated. By applying a time-varying bias voltage, the SMM's spin orientation can be manipulated with large bias voltage pulses. Moreover, the different magnetic configuration at high-resistance/low-resistance states can be ‘read out’ by utilizing relative low bias voltage. This device scheme can be implemented with current technologies (Khajetoorians et al 2013 Science 339 55) and has potential application in molecular spintronics and high-density nonvolatile memory devices.

  1. Induced resistance to hydrogen peroxide, UV and gamma radiation in bacillus species

    International Nuclear Information System (INIS)

    Bashandy, A.S.

    2005-01-01

    The catalase activity produced in four bacillus spp.(bacillus cereus, B. laterosporus, B. pumilus and B. subtilis (Escherichia coli was used for comparison) was measured and the sensitivity of these bacteria to hydrogen peroxide was tested. Bacillus spp. had higher resistance to hydrogen peroxide than E. coil. cultures of bacillus spp . When pretreated with sublethal level of hydrogen peroxide, became relatively resistant to the lethal effects of hydrogen than untreated control cultures. These pretreated cells were also resistant to lethality mediated by UV light and gamma radiation. The obtained results suggest that bacillus spp. Possess inducible defense mechanism (s) against the deleterious effects of oxidants and /or ionizing radiation

  2. Evolution of high yielding chickpea varieties, having improved plant type and disease resistance, through induced mutations

    International Nuclear Information System (INIS)

    Sadiq, M.; Hussan, M.; Haq, M.A.

    1989-01-01

    The breeding programme on the use of induced mutations, in chickpea for genetic variability for better plant type, grain yield and disease resistance has been started. The chickpea mutant variety is one of the leading varieties being extensively grown throughout Pakistan and has played its role in stabilizing the chickpea production in the country. Four chickpea varieties were treated, each with two dosed of gamma rays. The main purpose of the mutagenic treatment of these varieties/cultivars, was induce multiple resistance. (A.B.)

  3. Different Proteomics of Ca2+ on SA-induced Resistance to Botrytis cinerea in Tomato

    OpenAIRE

    Linlin Li; Peng Guo; Hua Jin; Tianlai Li

    2016-01-01

    This study aims to comprehensively study the effects of Ca2+ on the SA-induced resistance Botrytis cinerea in tomato through proteomics analysis. A proteomic approach was used to uncover the inducible proteins of tomato in the susceptible tomato cultivars ‘L402’ against Botrytis cinerea after salicylic acid (SA) and a combination treatment of CaCl2 and SA. The results showed that the use of combination treatment of CaCl2 and SA significantly enhanced tomato resistance against Botrytis cinerea...

  4. Progress toward overcoming hypoxia-induced resistance to solid tumor therapy

    International Nuclear Information System (INIS)

    Karakashev, Sergey V; Reginato, Mauricio J

    2015-01-01

    Hypoxic tumors are associated with poor clinical outcome for multiple types of human cancer. This may be due, in part, to hypoxic cancer cells being resistant to anticancer therapy, including radiation therapy, chemotherapy, and targeted therapy. Hypoxia inducible factor 1, a major regulator of cellular response to hypoxia, regulates the expression of genes that are involved in multiple aspects of cancer biology, including cell survival, proliferation, metabolism, invasion, and angiogenesis. Here, we review multiple pathways regulated by hypoxia/hypoxia inducible factor 1 in cancer cells and discuss the latest advancements in overcoming hypoxia-mediated tumor resistance

  5. Enabling Anticancer Therapeutics by Nanoparticle Carriers: The Delivery of Paclitaxel

    Directory of Open Access Journals (Sweden)

    Bing Yan

    2011-07-01

    Full Text Available Anticancer drugs, such as paclitaxel (PTX, are indispensable for the treatment of a variety of malignancies. However, the application of most drugs is greatly limited by the low water solubility, poor permeability, or high efflux from cells. Nanoparticles have been widely investigated to enable drug delivery due to their low toxicity, sustained drug release, molecular targeting, and additional therapeutic and imaging functions. This review takes paclitaxel as an example and compares different nanoparticle-based delivery systems for their effectiveness in cancer chemotherapy.

  6. Nano-particle nab-paclitaxel in treatment of metastatic breast cancer

    International Nuclear Information System (INIS)

    Barilla, R.; Dolinsky, J.

    2011-01-01

    Taxanes, paclitaxel and docetaxel, are together with anthracyclines the cornerstone of treatment of both early and advanced breast cancer. They are established as the standard of care either as monotherapy or in combination with other cytostatic agents and targeted therapies. However, despite their significant clinical activity in many cancer types, the use of taxanes is often limited by significant toxicities, including hypersensitivity reactions, which complicate treatment and diminish quality of life. Nanoparticle albumin-bound paclitaxel (nab-paclitaxel) is a 130 nm particle cremophor free formulation. Due to its special properties it allows to reach higher intratumoral concentrations of paclitaxel. In randomized phase II and phase III trials has been shown a superior efficacy and safety of nab-paclitaxel over paclitaxel or docetaxel. This new therapeutic formulation of paclitaxel may be therefore an adequate alternative to classic formulation of taxanes in the treatment of metastatic breast cancer. (author)

  7. Anesthesia with propofol induces insulin resistance systemically in skeletal and cardiac muscles and liver of rats

    Energy Technology Data Exchange (ETDEWEB)

    Yasuda, Yoshikazu; Fukushima, Yuji; Kaneki, Masao [Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Shriners Hospitals for Children, Harvard Medical School, Boston, MA 02114 (United States); Martyn, J.A. Jeevendra, E-mail: jmartyn@partners.org [Department of Anaesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Shriners Hospitals for Children, Harvard Medical School, Boston, MA 02114 (United States)

    2013-02-01

    Highlights: ► Propofol, as a model anesthetic drug, induced whole body insulin resistance. ► Propofol anesthesia decreased glucose infusion rate to maintain euglycemia. ► Propofol decreased insulin-mediated glucose uptake in skeletal and cardiac muscles. ► Propofol increased hepatic glucose output confirming hepatic insulin resistance. -- Abstract: Hyperglycemia together with hepatic and muscle insulin resistance are common features in critically ill patients, and these changes are associated with enhanced inflammatory response, increased susceptibility to infection, muscle wasting, and worsened prognosis. Tight blood glucose control by intensive insulin treatment may reduce the morbidity and mortality in intensive care units. Although some anesthetics have been shown to cause insulin resistance, it remains unknown how and in which tissues insulin resistance is induced by anesthetics. Moreover, the effects of propofol, a clinically relevant intravenous anesthetic, also used in the intensive care unit for sedation, on insulin sensitivity have not yet been investigated. Euglycemic hyperinsulinemic clamp study was performed in rats anesthetized with propofol and conscious unrestrained rats. To evaluate glucose uptake in tissues and hepatic glucose output [{sup 3}H]glucose and 2-deoxy[{sup 14}C]glucose were infused during the clamp study. Anesthesia with propofol induced a marked whole-body insulin resistance compared with conscious rats, as reflected by significantly decreased glucose infusion rate to maintain euglycemia. Insulin-stimulated tissue glucose uptake was decreased in skeletal muscle and heart, and hepatic glucose output was increased in propofol anesthetized rats. Anesthesia with propofol induces systemic insulin resistance along with decreases in insulin-stimulated glucose uptake in skeletal and heart muscle and attenuation of the insulin-mediated suppression of hepatic glucose output in rats.

  8. Anesthesia with propofol induces insulin resistance systemically in skeletal and cardiac muscles and liver of rats

    International Nuclear Information System (INIS)

    Yasuda, Yoshikazu; Fukushima, Yuji; Kaneki, Masao; Martyn, J.A. Jeevendra

    2013-01-01

    Highlights: ► Propofol, as a model anesthetic drug, induced whole body insulin resistance. ► Propofol anesthesia decreased glucose infusion rate to maintain euglycemia. ► Propofol decreased insulin-mediated glucose uptake in skeletal and cardiac muscles. ► Propofol increased hepatic glucose output confirming hepatic insulin resistance. -- Abstract: Hyperglycemia together with hepatic and muscle insulin resistance are common features in critically ill patients, and these changes are associated with enhanced inflammatory response, increased susceptibility to infection, muscle wasting, and worsened prognosis. Tight blood glucose control by intensive insulin treatment may reduce the morbidity and mortality in intensive care units. Although some anesthetics have been shown to cause insulin resistance, it remains unknown how and in which tissues insulin resistance is induced by anesthetics. Moreover, the effects of propofol, a clinically relevant intravenous anesthetic, also used in the intensive care unit for sedation, on insulin sensitivity have not yet been investigated. Euglycemic hyperinsulinemic clamp study was performed in rats anesthetized with propofol and conscious unrestrained rats. To evaluate glucose uptake in tissues and hepatic glucose output [ 3 H]glucose and 2-deoxy[ 14 C]glucose were infused during the clamp study. Anesthesia with propofol induced a marked whole-body insulin resistance compared with conscious rats, as reflected by significantly decreased glucose infusion rate to maintain euglycemia. Insulin-stimulated tissue glucose uptake was decreased in skeletal muscle and heart, and hepatic glucose output was increased in propofol anesthetized rats. Anesthesia with propofol induces systemic insulin resistance along with decreases in insulin-stimulated glucose uptake in skeletal and heart muscle and attenuation of the insulin-mediated suppression of hepatic glucose output in rats

  9. TNFα-Induced Mucin 4 Expression Elicits Trastuzumab Resistance in HER2-Positive Breast Cancer.

    Science.gov (United States)

    Mercogliano, María F; De Martino, Mara; Venturutti, Leandro; Rivas, Martín A; Proietti, Cecilia J; Inurrigarro, Gloria; Frahm, Isabel; Allemand, Daniel H; Deza, Ernesto Gil; Ares, Sandra; Gercovich, Felipe G; Guzmán, Pablo; Roa, Juan C; Elizalde, Patricia V; Schillaci, Roxana

    2017-02-01

    Although trastuzumab administration improved the outcome of HER2-positive breast cancer patients, resistance events hamper its clinical benefits. We demonstrated that TNFα stimulation in vitro induces trastuzumab resistance in HER2-positive breast cancer cell lines. Here, we explored the mechanism of TNFα-induced trastuzumab resistance and the therapeutic strategies to overcome it. Trastuzumab-sensitive breast cancer cells, genetically engineered to stably overexpress TNFα, and de novo trastuzumab-resistant tumors, were used to evaluate trastuzumab response and TNFα-blocking antibodies effectiveness respectively. Immunohistochemistry and antibody-dependent cell cytotoxicity (ADCC), together with siRNA strategy, were used to explore TNFα influence on the expression and function of its downstream target, mucin 4 (MUC4). The clinical relevance of MUC4 expression was studied in a cohort of 78 HER2-positive breast cancer patients treated with adjuvant trastuzumab. TNFα overexpression turned trastuzumab-sensitive cells and tumors into resistant ones. Histopathologic findings revealed mucin foci in TNFα-producing tumors. TNFα induced upregulation of MUC4 that reduced trastuzumab binding to its epitope and impaired ADCC. Silencing MUC4 enhanced trastuzumab binding, increased ADCC, and overcame trastuzumab and trastuzumab-emtansine antiproliferative effects in TNFα-overexpressing cells. Accordingly, administration of TNFα-blocking antibodies downregulated MUC4 and sensitized de novo trastuzumab-resistant breast cancer cells and tumors to trastuzumab. In HER2-positive breast cancer samples, MUC4 expression was found to be an independent predictor of poor disease-free survival (P = 0.008). We identified TNFα-induced MUC4 expression as a novel trastuzumab resistance mechanism. We propose MUC4 expression as a predictive biomarker of trastuzumab efficacy and a guide to combination therapy of TNFα-blocking antibodies with trastuzumab. Clin Cancer Res; 23(3); 636-48.

  10. Comparative effectiveness of early-line nab-paclitaxel vs. paclitaxel in patients with metastatic breast cancer: a US community-based real-world analysis

    Directory of Open Access Journals (Sweden)

    Mahtani RL

    2018-02-01

    Full Text Available Reshma L Mahtani,1 Monika Parisi,2 Stefan Glück,3 Quanhong Ni,2 Siyeon Park,4 Corey Pelletier,2 Claudio Faria,2 Fadi Braiteh5,6 1Division of Hematology/Oncology, University of Miami, Miami, FL, 2Health Economics and Outcomes Research, Celgene Corporation, Summit, NJ, 3Global Medical Affairs, Celgene Corporation, Summit, NJ, 4School of Pharmacy, The Ohio State University, Columbus, OH, 5Department of Hematology/Oncology, University of Nevada School of Medicine, Las Vegas, NV, 6Department of Hematology/Oncology, Comprehensive Cancer Centers of Nevada, Las Vegas, NV, USA Background: Real-world analyses of treatments for patients with metastatic breast cancer are limited. We evaluated the comparative effectiveness of nab-paclitaxel vs. paclitaxel in patients with metastatic breast cancer using data from an electronic medical record database from community practices across the USA.Methods: We performed a retrospective cohort study using fully de-identified data from an independent US electronic medical record platform of patients with metastatic breast cancer initiating single-agent nab-paclitaxel or paclitaxel as a first- or second-line treatment from December 1, 2010 to October 6, 2014. The clinical efficacy objectives were time to treatment discontinuation (TTD and time to next treatment (TTNT. Subgroup analyses were performed in patients with 2 types of metastatic breast cancer as follows: 1 hormone receptor-positive and human epidermal growth factor receptor 2 negative, and 2 triple-negative disease. Results: This analysis included 925 patients. Patients receiving nab-paclitaxel vs. paclitaxel had significantly longer TTD (median 4.2 vs. 2.8 months, P<0.0001 and TTNT (median 6.0 vs. 4.2 months, P<0.0001; similar outcomes were observed for patients with hormone receptor-positive/human epidermal growth factor receptor 2 negative disease. Compared with paclitaxel, nab-paclitaxel was associated with significantly longer TTD in patients with triple

  11. Gastrointestinal permeability in ovarian cancer and breast cancer patients treated with paclitaxel and platinum

    International Nuclear Information System (INIS)

    Melichar, Bohuslav; Hyšpler, Radomír; Dragounová, Emanuela; Dvořák, Josef; Kalábová, Hana; Tichá, Alena

    2007-01-01

    Combination of platinum derivatives with paclitaxel is currently the standard front line regimen for patients with epithelial ovarian carcinoma, and represents also an active regimen in patients with metastatic breast or unknown primary carcinomas. Measurement of intestinal permeability represents one of the potential methods of noninvasive laboratory assessment of gastrointestinal mucositis induced by chemotherapy, but little is known about intestinal permeability in patients treated with paclitaxel or platinum. Intestinal permeability was assessed in 36 breast and ovarian cancer patients treated with paclitaxel/platinum combination by measuring, using capillary gas chromatography, urinary sucrose, lactulose, xylose and mannitol after oral challenge. The significance of differences during the therapy compared to pre-treatment values was studied by Wilcoxon paired test. The differences between groups of patient were studied by Mann-Whitney U test. Fisher exact test was used to compare the frequency in different subgroups. After administration of the first dose, a significant (p < 0.05) decrease in xylose absorption and increased lactulose/mannitol, sucrose/mannitol, lactulose/xylose and sucrose/xylose ratios were observed, but these parameters returned subsequently to pre-treatment levels. Patients who experienced serious (grade 3 or 4) toxicity had at baseline significantly lower percentages of xylose, mannitol and sucrose, and higher lactulose/mannitol ratio. Nine of 13 (69%) patients with baseline lactulose/mannitol ratio 0.070 or above experienced serious toxicity compared to 4 out of 23 patients (17%) with the ratio below 0.070 (p = 0.002). Post-treatment lactulose, lactulose/mannitol, sucrose/mannitol and lactulose/xylose ratios were significantly increased in patients with serious toxicity. A transient significant increase in lactulose/monosaccharide and sucrose/monosaccharide ratios was observed in ovarian and breast cancer patients treated with paclitaxel

  12. Patient-reported (EORTC QLQ-CIPN20) versus physician-reported (CTCAE) quantification of oxaliplatin- and paclitaxel/carboplatin-induced peripheral neuropathy in NCCTG/Alliance clinical trials

    NARCIS (Netherlands)

    Le-Rademacher, J.; Kanwar, R.; Seisler, D.; Pachman, D.R.; Qin, R.; Abyzov, A.; Ruddy, K.J.; Banck, M.S.; Lavoie Smith, E.M.; Dorsey, S.G.; Aaronson, N.K.; Sloan, J.; Loprinzi, C.L.; Beutler, A.S.

    2017-01-01

    PURPOSE: Clinical practice guidelines on chemotherapy-induced peripheral neuropathy (CIPN) use the NCI Common Terminology Criteria for Adverse Events (CTCAE), while recent clinical trials employ a potentially superior measure, the European Organization for Research and Treatment of Cancer Quality of

  13. Silvicultural Attempts to Induce Browse Resistance in Conifer Seedlings

    Directory of Open Access Journals (Sweden)

    Bruce A. Kimball

    2011-01-01

    Full Text Available A multiyear study was conducted to determine if soil amendment combined with topical application of elemental sulfur could be employed to reduce deer browse damage to four conifer species. Fertilizer and sulfur were applied to conifer seedlings at seven sites near Corvallis, OR. Growth and browse damage data were collected for all seedlings over a period of 17 months. Additionally, foliar concentrations of monoterpenes and simple carbohydrates were assessed in western redcedar (Thuja plicata seedlings over a period of three years. Fertilization and sulfur treatments had a moderate impact on growth and no influence on browse damage or the chemical responses. Over the course of the study, browse damage diminished while foliar monoterpene concentrations increased in redcedar. It appears that silvicultural manipulation via sulfur application and/or soil amendment cannot accelerate or alter the ontogenetical changes that may naturally defend seedlings against mammalian herbivores. In a brief trial with captive deer, redcedar browse resistance was influenced by seedling maturation, but not monoterpene content. Other maturation effects may yield significant browse protection to young seedlings.

  14. Chemical products induce resistance to Xanthomonas perforans in tomato

    Directory of Open Access Journals (Sweden)

    Adriana Terumi Itako

    2015-09-01

    Full Text Available The bacterial spot of tomato, caused by Xanthomonas spp., is a very important disease, especially in the hot and humid periods of the year. The chemical control of the disease has not been very effective for a number of reasons. This study aimed to evaluate, under greenhouse conditions, the efficacy of leaf-spraying chemicals (acibenzolar-S-methyl (ASM (0.025 g.L−1, fluazinam (0.25 g.L−1, pyraclostrobin (0.08 g.L−1, pyraclostrobin + methiran (0.02 g.L−1 + 2.2 g.L−1, copper oxychloride (1.50 g.L−1, mancozeb + copper oxychloride (0.88 g.L−1 + 0.60 g.L−1, and oxytetracycline (0.40 g.L−1 on control of bacterial spot. Tomatoes Santa Clara and Gisele cultivars were pulverized 3 days before inoculation with Xanthomonas perforans. The production of enzymes associated with resistance induction (peroxidase, polyphenol oxidase, phenylalanine ammonia-lyase, β-1,3-glucanase, and protease was quantified from leaf samples collected 24 hours before and 24 hours after chemical spraying and at 1, 2, 4, 6, and 8 days after bacterial inoculation. All products tested controlled bacterial spot, but only ASM, pyraclostrobin, and pyraclostrobin + metiram increased the production of peroxidase in the leaves of the two tomato cultivars, and increased the production of polyphenol oxidase and β-1,3-glucanase in the Santa Clara cultivar.

  15. Chemical products induce resistance to Xanthomonas perforans in tomato.

    Science.gov (United States)

    Itako, Adriana Terumi; Tolentino Júnior, João Batista; Silva Júnior, Tadeu Antônio Fernandes da; Soman, José Marcelo; Maringoni, Antonio Carlos

    2015-01-01

    The bacterial spot of tomato, caused by Xanthomonas spp., is a very important disease, especially in the hot and humid periods of the year. The chemical control of the disease has not been very effective for a number of reasons. This study aimed to evaluate, under greenhouse conditions, the efficacy of leaf-spraying chemicals (acibenzolar-S-methyl (ASM) (0.025 g.L(-1)), fluazinam (0.25 g.L(-1)), pyraclostrobin (0.08 g.L(-1)), pyraclostrobin + methiran (0.02 g.L(-1) + 2.2 g.L(-1)), copper oxychloride (1.50 g.L(-1)), mancozeb + copper oxychloride (0.88 g.L(-1) + 0.60 g.L(-1)), and oxytetracycline (0.40 g.L(-1))) on control of bacterial spot. Tomatoes Santa Clara and Gisele cultivars were pulverized 3 days before inoculation with Xanthomonas perforans. The production of enzymes associated with resistance induction (peroxidase, polyphenol oxidase, phenylalanine ammonia-lyase, β-1,3-glucanase, and protease) was quantified from leaf samples collected 24 hours before and 24 hours after chemical spraying and at 1, 2, 4, 6, and 8 days after bacterial inoculation. All products tested controlled bacterial spot, but only ASM, pyraclostrobin, and pyraclostrobin + metiram increased the production of peroxidase in the leaves of the two tomato cultivars, and increased the production of polyphenol oxidase and β-1,3-glucanase in the Santa Clara cultivar.

  16. Safety and Efficacy of Low-dose Nanoparticle Albumin-bound Paclitaxel for HER2-negative Metastatic Breast Cancer.

    Science.gov (United States)

    Takashima, Tsutomu; Kawajiri, Hidemi; Nishimori, Takeo; Tei, Seika; Nishimura, Shigehiko; Yamagata, Shigehito; Tokunaga, Shinya; Mizuyama, Yoko; Sunami, Takeshi; Tezuka, Kenji; Ikeda, Katsumi; Ogawa, Yoshinari; Kashiwagi, Shinichiro; Noda, Satoru; Onoda, Naoyoshi; Ishikawa, Tetsuro; Kudoh, Shinzoh; Takada, Minoru; Hirakawa, Kosei; Ohira, Masaichi

    2018-01-01

    Nab-paclitaxel (nab-PTX) is an albumin-bound paclitaxel formulation. Although nab-PTX has shown superior efficacy compared to conventional paclitaxel (PTX) in metastatic breast cancer (MBC), chemotherapy-induced peripheral neuropathy (CIPN) was more frequently observed in nab-PTX. In this study, we aimed to estimate the feasibility of the nab-PTX 175 mg/m 2 /3weeks regimen. Patients having metastatic or inoperable HER2-negative breast cancer received 175 mg/m 2 of nab-PTX every three weeks. The primary endpoint was safety and the secondary endpoints were response and survival. Seventeen patients were enrolled with a median age of 64 years. Ten patients had estrogen receptor positive disease and seven had triple-negative disease. CIPN was observed in seven patients (41%) however, grade 3 CIPN was only seen in one patient (6%). Objective response rate was 41% and progression-free survival was 23 weeks. Nab-PTX 175 mg/m 2 /3wks regimen has a good safety profile and less frequent CIPN. This regimen can contribute to the strategy of MBC treatment. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  17. The role of autophagy in THP-1 macrophages resistance to HIV- vpr-induced apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Hua-ying, E-mail: zhouhuaying_2004@126.com; Zheng, Yu-huang; He, Yan; Chen, Zi; He, Bo

    2017-02-01

    Macrophages are resistant to cell death and are one of HIV reservoirs. HIV viral protein Vpr has the potential to promote infection of and survival of macrophages, which could be a highly significant factor in the development and/or maintenance of macrophage viral reservoirs. However, the impact of vpr on macrophages resistance to apoptosis is yet to be comprehended. Autophagy is a cell survival mechanism under stress state. In this study, we investigated whether autophagy is involved in macrophages resistant to vpr-induced apoptosis. Using the THP1 macrophages, we studied the interconnection between macrophages resistance to apoptosis and autophagy. We found that vpr is able to trigger autophagy in transfected THP-1 macrophages confirmed by electron microscopy (EM) and western blot analysis, and inhibition of autophagy with 3MA increased vpr-induced apoptosis. The results indicate that autophagy may be responsible for maintenance of macrophage HIV reservoirs. - Highlights: • HIV Vpr is able to trigger autophagy in transfected THP-1 macrophages. • Autophagy inhibition increases vpr-transfected THP1-macrophages apoptosis. • Autophagy is involved in THP-1 macrophages resistant to vpr-induced apoptosis.

  18. A phase I clinical trial of bavituximab and paclitaxel in patients with HER2 negative metastatic breast cancer

    International Nuclear Information System (INIS)

    Chalasani, Pavani; Marron, Marilyn; Roe, Denise; Clarke, Kathryn; Iannone, Maria; Livingston, Robert B; Shan, Joseph S; Stopeck, Alison T

    2015-01-01

    Bavituximab is a chimeric monoclonal antibody that targets phosphatidylserine (PS). PS is externalized on cells in the tumor microenvironment when exposed to hypoxia and/or other physiological stressors. On attaching to PS, bavituximab is thought to promote antitumor immunity through its effects on PS receptors in monocytes, and myeloid-derived suppressor cells, as well as trigger antitumor effects by inducing an antibody-dependent cellular cytotoxicity on tumor-associated endothelial cells. We conducted a phase I clinical trial of bavituximab in combination with paclitaxel in patients with HER2-negative metastatic breast cancer. Patients were treated with weekly paclitaxel (80 mg/m 2 for 3/4 weeks) and weekly bavituximab (3 mg/kg for 4/4 weeks). Correlative studies included the measurement of circulating microparticles, endothelial cells, and apoptotic tumor cells by flow cytometry. Fourteen patients with metastatic breast cancer were enrolled; all were evaluable for toxicity and 13 were evaluable for response. Treatment resulted in an overall response rate (RR) of 85% with a median progression-free survival (PFS) of 7.3 months. Bone pain, fatigue, headache, and neutropenia were the most common adverse effects. Infusion-related reactions were the most common adverse event related to bavituximab therapy. Correlative studies showed an increase in the PS-expressing apoptotic circulating tumor cells in response to bavituximab, but not with paclitaxel. No changes in the number of circulating endothelial cells or apoptotic endothelial cells were observed with therapy. Platelet and monocyte-derived microparticles decreased after initiation of bavituximab. Bavituximab in combination with paclitaxel is well tolerated for treatment of patients with metastatic breast cancer with promising results observed in terms of clinical RRs and PFS. The toxicity profile of bavituximab is notable for manageable infusion-related reactions with no evidence for increased thrombogenicity

  19. Unaltered Prion Pathogenesis in a Mouse Model of High-Fat Diet-Induced Insulin Resistance.

    Directory of Open Access Journals (Sweden)

    Caihong Zhu

    Full Text Available Epidemiological, clinical, and experimental animal studies suggest a strong correlation between insulin resistance and Alzheimer's disease. In fact, type-2 diabetes is considered an important risk factor of developing Alzheimer's disease. In addition, impaired insulin signaling in the Alzheimer's disease brain may promote Aβ production, impair Aβ clearance and induce tau hyperphosphorylation, thereby leading to deterioration of the disease. The pathological prion protein, PrPSc, deposits in the form of extracellular aggregates and leads to dementia, raising the question as to whether prion pathogenesis may also be affected by insulin resistance. We therefore established high-fat diet-induced insulin resistance in tga20 mice, which overexpress the prion protein. We then inoculated the insulin-resistant mice with prions. We found that insulin resistance in tga20 mice did not affect prion disease progression, PrPSc deposition, astrogliosis or microglial activation, and had no effect on survival. Our study demonstrates that in a mouse model, insulin resistance does not significantly contribute to prion pathogenesis.

  20. Ghrelin- and GH-induced insulin resistance: no association with retinol-binding protein-4

    DEFF Research Database (Denmark)

    Vestergaard, Esben Thyssen; Krag, Morten B; Poulsen, Morten M

    2013-01-01

    Supraphysiological levels of ghrelin and GH induce insulin resistance. Serum levels of retinol-binding protein-4 (RBP4) correlate inversely with insulin sensitivity in patients with type 2 diabetes. We aimed to determine whether ghrelin and GH affect RBP4 levels in human subjects....

  1. Induced disease resistance of satsuma mandarings against penicillium digitatum by gamma irradiation

    International Nuclear Information System (INIS)

    Jeong, Rae Dong

    2017-01-01

    Gamma irradiation, which is a type of ionizing radiation, can be used as a fruit inducible factor. In the present study, the effects of gamma irradiation on the resistance of mandarin fruits against Penicillium digitatum, the causal agent of postharvest green mold disease, were investigated. Pretreatment of a low dose of gamma irradiation effectively reduced the disease incidence and lesion diameter of mandarin fruits inoculated with P. digatatum during storage for 14 d. Interestingly, exposed to 400 Gy of gamma irradiation significantly maintained firmness and stimulated the synthesis of defense-related enzymes, (e.g., β-1,3-glucanase, phenylalanine, peroxidase, and polyphenol oxidase) and pathogenesis-related (PR) genes (e.g., PR-1 and PR-2). Therefore, the gamma irradiation-induced resistance against P. digatatum involves both changes of phenolic compounds and the induction of expression of defense-related genes. In addition, scanning electron microscopy analysis revealed that induced disease resistance by gamma irradiation signifcantly inhibits the growth of P. digatatum in mandarin fruits. These results suggest that the exposure of gamma irradiation is a potential methods for inducing the disease resistance of fruit to postharvest fungal pathogens and for extending the postharvest life of mandarin fruit

  2. Bio-based resistance inducers for sustainable plant protection against pathogens

    Czech Academy of Sciences Publication Activity Database

    Burketová, Lenka; Trdá, Lucie; Ott, P.G.; Valentová, O.

    2015-01-01

    Roč. 33, č. 6 (2015), s. 994-1004 ISSN 0734-9750 R&D Projects: GA MŠk(CZ) LD14056 Institutional support: RVO:61389030 Keywords : Induced resistance * Elicitor * Chitosan Subject RIV: GF - Plant Pathology, Vermin, Weed, Plant Protection Impact factor: 9.848, year: 2015

  3. Model of parameters controlling resistance of pipeline steels to hydrogen-induced cracking

    KAUST Repository

    Traidia, Abderrazak; El-Sherik, A. M.; Duval, Sé bastien; Lubineau, Gilles; El Yagoubi, Jalal

    2014-01-01

    NACE MR0175/ISO 15156-2 standard provides test conditions and acceptance criteria to evaluate the resistance of carbon and low-alloy steels to hydrogen-induced cracking (HIC). The second option proposed by this standard offers a large flexibility

  4. Continuous administration of an elemental diet induces insulin resistance in neonatal pigs

    Science.gov (United States)

    We previously showed that total parenteral nutrition (TPN) compared to intermittent enteral feeding of a milk-based formula induces insulin resistance and hepatic steatosis in neonatal pigs. We hypothesized that intravenous (IV) feeding rather than the nature of the diet (elemental vs polymeric) or ...

  5. Induced disease resistance of satsuma mandarings against penicillium digitatum by gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Rae Dong [Dept. of Applied Biology, Institute of Environmentally Friendly Agriculture, Chonnam National University, Gwangju (Korea, Republic of)

    2017-06-15

    Gamma irradiation, which is a type of ionizing radiation, can be used as a fruit inducible factor. In the present study, the effects of gamma irradiation on the resistance of mandarin fruits against Penicillium digitatum, the causal agent of postharvest green mold disease, were investigated. Pretreatment of a low dose of gamma irradiation effectively reduced the disease incidence and lesion diameter of mandarin fruits inoculated with P. digatatum during storage for 14 d. Interestingly, exposed to 400 Gy of gamma irradiation significantly maintained firmness and stimulated the synthesis of defense-related enzymes, (e.g., β-1,3-glucanase, phenylalanine, peroxidase, and polyphenol oxidase) and pathogenesis-related (PR) genes (e.g., PR-1 and PR-2). Therefore, the gamma irradiation-induced resistance against P. digatatum involves both changes of phenolic compounds and the induction of expression of defense-related genes. In addition, scanning electron microscopy analysis revealed that induced disease resistance by gamma irradiation signifcantly inhibits the growth of P. digatatum in mandarin fruits. These results suggest that the exposure of gamma irradiation is a potential methods for inducing the disease resistance of fruit to postharvest fungal pathogens and for extending the postharvest life of mandarin fruit.

  6. Effect of Glucocorticoid-Induced Insulin Resistance on Follicle Development and Ovulation1

    Science.gov (United States)

    Hackbart, Katherine S.; Cunha, Pauline M.; Meyer, Rudelle K.; Wiltbank, Milo C.

    2013-01-01

    ABSTRACT Polycystic ovarian syndrome (PCOS) is characterized by hyperandrogenemia, polycystic ovaries, and menstrual disturbance and a clear association with insulin resistance. This research evaluated whether induction of insulin resistance, using dexamethasone (DEX), in a monovular animal model, the cow, could produce an ovarian phenotype similar to PCOS. In all of these experiments, DEX induced insulin resistance in cows as shown by increased glucose, insulin, and HOMA-IR (homeostasis model assessment of insulin resistance). Experiment 1: DEX induced anovulation (zero of five DEX vs. four of four control cows ovulated) and decreased circulating estradiol (E2). Experiment 2: Gonadotropin-releasing hormone (GnRH) was administered to determine pituitary and follicular responses during insulin resistance. GnRH induced a luteinizing hormone (LH) surge and ovulation in both DEX (seven of seven) and control (seven of seven) cows. Experiment 3: E2 was administered to determine hypothalamic responsiveness after induction of an E2 surge in DEX (eight of eight) and control (eight of eight) cows. An LH surge was induced in control (eight of eight) but not DEX (zero of eight) cows. All control (eight of eight) but only two of eight DEX cows ovulated within 60 h of E2 administration. Experiment 4: Short-term DEX was initiated 24 h after induced luteal regression to determine if DEX could acutely block ovulation before peak insulin resistance was induced, similar to progesterone (P4). All control (five of five), no P4-treated (zero of six), and 50% of DEX-treated (three of six) cows ovulated by 96 h after luteal regression. All anovular cows had reduced circulating E2. These data are consistent with DEX creating a lesion in hypothalamic positive feedback to E2 without altering pituitary responsiveness to GnRH or ovulatory responsiveness of follicles to LH. It remains to be determined if the considerable insulin resistance and the reduced follicular E2 production induced by DEX

  7. Study on the effect of paclitaxel nanostructure lipid carrier cooperated with radiation on the KB Cells

    International Nuclear Information System (INIS)

    Liu Min; Li Zhihui; Xu Yujie

    2011-01-01

    Objective: To investigate the cytotoxicity effect of paclitaxel nanostructure lipid carrier (TAX-NLC) cooperated with radiation treatment on the KB cells. Methods: The cytotoxicity effect of TAX-NLC compared with free paclitaxel (TAX) on the KB cells was measured by MTT assay, and the cell cycle distribution was analyzed by flow cytometry. Results: The cytotoxicity effect of TAX-NLC was stronger than that of the free TAX. And the cooperative effect between the TAX-NLC and ionized radiation were observed, the cooperative effect of TAX-NLC was stronger than that of the free TAX. Flow cytometric analysis indicated that the rearrangement of cell cycle in KB cells were induced by TAX-NLC. The more G2/M phase cells were observed in KB cells treated by TAX-NLC compared with free TAX. The effect of TAX-NLC in the rearrangement of cell cycle was stronger than that of the free TAX. Conclusion: The cytotoxicity effect of TAX-NLC is stronger than that of the free TAX. And the cooperative effect of TAX-NLC is stronger than that of the free TAX. (authors)

  8. Alterations in tumor necrosis factor signaling pathways are associated with cytotoxicity and resistance to taxanes: a study in isogenic resistant tumor cells

    Science.gov (United States)

    2012-01-01

    Introduction The taxanes paclitaxel and docetaxel are widely used in the treatment of breast, ovarian, and other cancers. Although their cytotoxicity has been attributed to cell-cycle arrest through stabilization of microtubules, the mechanisms by which tumor cells die remains unclear. Paclitaxel has been shown to induce soluble tumor necrosis factor alpha (sTNF-α) production in macrophages, but the involvement of TNF production in taxane cytotoxicity or resistance in tumor cells has not been established. Our study aimed to correlate alterations in the TNF pathway with taxane cytotoxicity and the acquisition of taxane resistance. Methods MCF-7 cells or isogenic drug-resistant variants (developed by selection for surviving cells in increasing concentrations of paclitaxel or docetaxel) were assessed for sTNF-α production in the absence or presence of taxanes by enzyme-linked immunosorbent assay (ELISA) and for sensitivity to docetaxel or sTNF-α by using a clonogenic assay (in the absence or presence of TNFR1 or TNFR2 neutralizing antibodies). Nuclear factor (NF)-κB activity was also measured with ELISA, whereas gene-expression changes associated with docetaxel resistance in MCF-7 and A2780 cells were determined with microarray analysis and quantitative reverse transcription polymerase chain reaction (RTqPCR). Results MCF-7 and A2780 cells increased production of sTNF-α in the presence of taxanes, whereas docetaxel-resistant variants of MCF-7 produced high levels of sTNF-α, although only within a particular drug-concentration threshold (between 3 and 45 nM). Increased production of sTNF-α was NF-κB dependent and correlated with decreased sensitivity to sTNF-α, decreased levels of TNFR1, and increased survival through TNFR2 and NF-κB activation. The NF-κB inhibitor SN-50 reestablished sensitivity to docetaxel in docetaxel-resistant MCF-7 cells. Gene-expression analysis of wild-type and docetaxel-resistant MCF-7, MDA-MB-231, and A2780 cells identified changes

  9. Hypoxia-induced resistance to doxorubicin and methotrexate in human melanoma cell lines in vitro.

    Science.gov (United States)

    Sanna, K; Rofstad, E K

    1994-07-15

    Rodent cell lines can develop resistance to doxorubicin and methotrexate during hypoxic stress. This has so far not been observed in human tumor cell lines. The purpose of our communication is to show that doxorubicin and methotrexate resistance can also develop in human melanoma cells during exposure to hypoxia. Four cell lines (BEX-c, COX-c, SAX-c, WIX-c) have been studied. Cells were exposed to hypoxia (O2 concentration WIX-c. BEX-c and SAX-c were sensitive to methotrexate without hypoxia pre-treatment, whereas COX-c and WIX-c were resistant initially. Hypoxia-induced drug resistance was present immediately after reoxygenation and tended to decrease with time but remained statistically significant even 42 hr after reoxygenation.

  10. Combined doxorubicin and paclitaxel in advanced breast cancer

    DEFF Research Database (Denmark)

    Gehl, J; Boesgaard, M; Paaske, T

    1996-01-01

    -550). The main toxicities were neutropenia, parestesia, nausea/vomiting, alopecia, myalgia and cardiotoxicity. Fifteen patients (50%) had reductions of left ventricular ejection fraction of below normal levels and 6 of these patients (20%) developed congestive heart failure. CONCLUSION: The combination...... of doxorubicin and paclitaxel is highly active, but is accompanied by the dose-limiting toxic effects of neutropenia, neuropathy and cardiotoxicity....

  11. Polyelectrolyte stabilized multilayered liposomes for oral delivery of paclitaxel

    DEFF Research Database (Denmark)

    Jain, Sanyog; Kumar, Dinesh; Swarnakar, Nitin K

    2012-01-01

    Paclitaxel (PTX) loaded layersome formulations were prepared using layer-by-layer assembly of the polyelectrolytes over liposomes. Stearyl amine was utilized to provide positive charge to the liposomes, which were subsequently coated with anionic polymer polyacrylic acid (PAA) followed by coating...

  12. Induced systemic resistance in cucumber and Arabidopsis thaliana by the combination of Trichoderma harzianum Tr6 and Pseudomonas sp.

    NARCIS (Netherlands)

    Alizadeh, H.; Behboudi, K.; Amadzadeh, M.; Javan-Nikkhah, M.; Zamioudis, C; Pieterse, C.M.J.; Bakker, P.A.H.M.

    2013-01-01

    Trichoderma species and fluorescent Pseudomonas spp. have been reported to induce systemic resistance in plants. In this study the effectiveness of a combination of these biological control agents on the efficacy of induced resistance was investigated in cucumber and the model plant Arabidopsis

  13. Pomegranate seed oil, a rich source of punicic acid, prevents diet-induced obesity and insulin resistance in mice

    NARCIS (Netherlands)

    Vroegrijk, Irene O. C. M.; van Diepen, Janna A.; van den Berg, Sjoerd; Westbroek, Irene; Keizer, Hiskias; Gambelli, Luisa; Hontecillas, Raquel; Bassaganya-Riera, Josep; Zondag, Gerben C. M.; Romijn, Johannes A.; Havekes, Louis M.; Voshol, Peter J.

    2011-01-01

    Pomegranate seed oil has been shown to protect against diet induced obesity and insulin resistance. To characterize the metabolic effects of punicic acid on high fat diet induced obesity and insulin resistance. High-fat diet or high-fat diet with 1% Pomegranate seed oil (PUA) was fed for 12weeks to

  14. Pomegranate seed oil, a rich source of punicic acid, prevents diet-induced obesity and insulin resistance in mice.

    NARCIS (Netherlands)

    Vroegrijk, I.O.; Diepen, J.A. van; Berg, S.; Westbroek, I.; Keizer, H.; Gambelli, L.; Hontecillas, R.; Bassaganya-Riera, J.; Zondag, G.C.; Romijn, J.A.; Havekes, L.M.; Voshol, P.J.

    2011-01-01

    BACKGROUND: Pomegranate seed oil has been shown to protect against diet induced obesity and insulin resistance. OBJECTIVE: To characterize the metabolic effects of punicic acid on high fat diet induced obesity and insulin resistance. DESIGN: High-fat diet or high-fat diet with 1% Pomegranate seed

  15. Acute and long-term administration of palmitoylcarnitine induces muscle-specific insulin resistance in mice.

    Science.gov (United States)

    Liepinsh, Edgars; Makrecka-Kuka, Marina; Makarova, Elina; Volska, Kristine; Vilks, Karlis; Sevostjanovs, Eduards; Antone, Unigunde; Kuka, Janis; Vilskersts, Reinis; Lola, Daina; Loza, Einars; Grinberga, Solveiga; Dambrova, Maija

    2017-09-10

    Acylcarnitine accumulation has been linked to perturbations in energy metabolism pathways. In this study, we demonstrate that long-chain (LC) acylcarnitines are active metabolites involved in the regulation of glucose metabolism in vivo. Single-dose administration of palmitoylcarnitine (PC) in fed mice induced marked insulin insensitivity, decreased glucose uptake in muscles, and elevated blood glucose levels. Increase in the content of LC acylcarnitine induced insulin resistance by impairing Akt phosphorylation at Ser473. The long-term administration of PC using slow-release osmotic minipumps induced marked hyperinsulinemia, insulin resistance, and glucose intolerance, suggesting that the permanent accumulation of LC acylcarnitines can accelerate the progression of insulin resistance. The decrease of acylcarnitine content significantly improved glucose tolerance in a mouse model of diet-induced glucose intolerance. In conclusion, we show that the physiological increase in content of acylcarnitines ensures the transition from a fed to fasted state in order to limit glucose metabolism in the fasted state. In the fed state, the inability of insulin to inhibit LC acylcarnitine production induces disturbances in glucose uptake and metabolism. The reduction of acylcarnitine content could be an effective strategy to improve insulin sensitivity. © 2017 BioFactors, 43(5):718-730, 2017. © 2017 The Authors BioFactors published by Wiley Periodicals, Inc. on behalf of International Union of Biochemistry and Molecular Biology.

  16. Gefitinib or carboplatin-paclitaxel in pulmonary adenocarcinoma.

    Science.gov (United States)

    Mok, Tony S; Wu, Yi-Long; Thongprasert, Sumitra; Yang, Chih-Hsin; Chu, Da-Tong; Saijo, Nagahiro; Sunpaweravong, Patrapim; Han, Baohui; Margono, Benjamin; Ichinose, Yukito; Nishiwaki, Yutaka; Ohe, Yuichiro; Yang, Jin-Ji; Chewaskulyong, Busyamas; Jiang, Haiyi; Duffield, Emma L; Watkins, Claire L; Armour, Alison A; Fukuoka, Masahiro

    2009-09-03

    Previous, uncontrolled studies have suggested that first-line treatment with gefitinib would be efficacious in selected patients with non-small-cell lung cancer. In this phase 3, open-label study, we randomly assigned previously untreated patients in East Asia who had advanced pulmonary adenocarcinoma and who were nonsmokers or former light smokers to receive gefitinib (250 mg per day) (609 patients) or carboplatin (at a dose calculated to produce an area under the curve of 5 or 6 mg per milliliter per minute) plus paclitaxel (200 mg per square meter of body-surface area) (608 patients). The primary end point was progression-free survival. The 12-month rates of progression-free survival were 24.9% with gefitinib and 6.7% with carboplatin-paclitaxel. The study met its primary objective of showing the noninferiority of gefitinib and also showed its superiority, as compared with carboplatin-paclitaxel, with respect to progression-free survival in the intention-to-treat population (hazard ratio for progression or death, 0.74; 95% confidence interval [CI], 0.65 to 0.85; P<0.001). In the subgroup of 261 patients who were positive for the epidermal growth factor receptor gene (EGFR) mutation, progression-free survival was significantly longer among those who received gefitinib than among those who received carboplatin-paclitaxel (hazard ratio for progression or death, 0.48; 95% CI, 0.36 to 0.64; P<0.001), whereas in the subgroup of 176 patients who were negative for the mutation, progression-free survival was significantly longer among those who received carboplatin-paclitaxel (hazard ratio for progression or death with gefitinib, 2.85; 95% CI, 2.05 to 3.98; P<0.001). The most common adverse events were rash or acne (in 66.2% of patients) and diarrhea (46.6%) in the gefitinib group and neurotoxic effects (69.9%), neutropenia (67.1%), and alopecia (58.4%) in the carboplatin-paclitaxel group. Gefitinib is superior to carboplatin-paclitaxel as an initial treatment for

  17. Tetradecylthioacetic acid prevents high fat diet induced adiposity and insulin resistance

    DEFF Research Database (Denmark)

    Madsen, Lise; Guerre-Millo, Michéle; Flindt, Esben N

    2002-01-01

    Tetradecylthioacetic acid (TTA) is a non-beta-oxidizable fatty acid analog, which potently regulates lipid homeostasis. Here we evaluate the ability of TTA to prevent diet-induced and genetically determined adiposity and insulin resistance. In Wistar rats fed a high fat diet, TTA administration...... completely prevented diet-induced insulin resistance and adiposity. In genetically obese Zucker (fa/fa) rats TTA treatment reduced the epididymal adipose tissue mass and improved insulin sensitivity. All three rodent peroxisome proliferator-activated receptor (PPAR) subtypes were activated by TTA...... that a TTA-induced increase in hepatic fatty acid oxidation and ketogenesis drains fatty acids from blood and extrahepatic tissues and that this contributes significantly to the beneficial effects of TTA on fat mass accumulation and peripheral insulin sensitivity....

  18. Nicotine induces resistance to chemotherapy by modulating mitochondrial signaling in lung cancer.

    Science.gov (United States)

    Zhang, Jingmei; Kamdar, Opal; Le, Wei; Rosen, Glenn D; Upadhyay, Daya

    2009-02-01

    Continued smoking causes tumor progression and resistance to therapy in lung cancer. Carcinogens possess the ability to block apoptosis, and thus may induce development of cancers and resistance to therapy. Tobacco carcinogens have been studied widely; however, little is known about the agents that inhibit apoptosis, such as nicotine. We determine whether mitochondrial signaling mediates antiapoptotic effects of nicotine in lung cancer. A549 cells were exposed to nicotine (1 muM) followed by cisplatin (35 muM) plus etoposide (20 muM) for 24 hours. We found that nicotine prevented chemotherapy-induced apoptosis, improved cell survival, and caused modest increases in DNA synthesis. Inhibition of mitogen-activated protein kinase (MAPK) and Akt prevented the antiapoptotic effects of nicotine and decreased chemotherapy-induced apoptosis. Small interfering RNA MAPK kinase-1 blocked antiapoptotic effects of nicotine, whereas small interfering RNA MAPK kinase-2 blocked chemotherapy-induced apoptosis. Nicotine prevented chemotherapy-induced reduction in mitochondrial membrane potential and caspase-9 activation. Antiapoptotic effects of nicotine were blocked by mitochondrial anion channel inhibitor, 4,4'diisothiocyanatostilbene-2,2'disulfonic acid. Chemotherapy enhanced translocation of proapoptotic Bax to the mitochondria, whereas nicotine blocked these effects. Nicotine up-regulated Akt-mediated antiapoptotic X-linked inhibitor of apoptosis protein and phosphorylated proapoptotic Bcl2-antagonist of cell death. The A549-rho0 cells, which lack mitochondrial DNA, demonstrated partial resistance to chemotherapy-induced apoptosis, but blocked the antiapoptotic effects of nicotine. Accordingly, we provide evidence that nicotine modulates mitochondrial signaling and inhibits chemotherapy-induced apoptosis in lung cancer. The mitochondrial regulation of nicotine imposes an important mechanism that can critically impair the treatment of lung cancer, because many cancer

  19. Coconut Oil Aggravates Pressure Overload-Induced Cardiomyopathy without Inducing Obesity, Systemic Insulin Resistance, or Cardiac Steatosis.

    Science.gov (United States)

    Muthuramu, Ilayaraja; Amin, Ruhul; Postnov, Andrey; Mishra, Mudit; Jacobs, Frank; Gheysens, Olivier; Van Veldhoven, Paul P; De Geest, Bart

    2017-07-18

    Studies evaluating the effects of high-saturated fat diets on cardiac function are most often confounded by diet-induced obesity and by systemic insulin resistance. We evaluated whether coconut oil, containing C12:0 and C14:0 as main fatty acids, aggravates pressure overload-induced cardiomyopathy induced by transverse aortic constriction (TAC) in C57BL/6 mice. Mortality rate after TAC was higher ( p coconut oil diet-fed mice than in standard chow-fed mice (hazard ratio 2.32, 95% confidence interval 1.16 to 4.64) during eight weeks of follow-up. The effects of coconut oil on cardiac remodeling occurred in the absence of weight gain and of systemic insulin resistance. Wet lung weight was 1.76-fold ( p coconut oil mice than in standard chow mice. Myocardial capillary density ( p coconut oil mice than in standard chow mice. Myocardial glucose uptake was 1.86-fold ( p coconut oil mice and was accompanied by higher myocardial pyruvate dehydrogenase levels and higher acetyl-CoA carboxylase levels. The coconut oil diet increased oxidative stress. Myocardial triglycerides and free fatty acids were lower ( p coconut oil mice. In conclusion, coconut oil aggravates pressure overload-induced cardiomyopathy.

  20. Suppression of Ghrelin Exacerbates HFCS-Induced Adiposity and Insulin Resistance.

    Science.gov (United States)

    Ma, Xiaojun; Lin, Ligen; Yue, Jing; Wu, Chia-Shan; Guo, Cathy A; Wang, Ruitao; Yu, Kai-Jiang; Devaraj, Sridevi; Murano, Peter; Chen, Zheng; Sun, Yuxiang

    2017-06-19

    High fructose corn syrup (HFCS) is widely used as sweetener in processed foods and soft drinks in the United States, largely substituting sucrose (SUC). The orexigenic hormone ghrelin promotes obesity and insulin resistance; ghrelin responds differently to HFCS and SUC ingestion. Here we investigated the roles of ghrelin in HFCS- and SUC-induced adiposity and insulin resistance. To mimic soft drinks, 10-week-old male wild-type (WT) and ghrelin knockout ( Ghrelin -/- ) mice were subjected to ad lib. regular chow diet supplemented with either water (RD), 8% HFCS (HFCS), or 10% sucrose (SUC). We found that SUC-feeding induced more robust increases in body weight and body fat than HFCS-feeding. Comparing to SUC-fed mice, HFCS-fed mice showed lower body weight but higher circulating glucose and insulin levels. Interestingly, we also found that ghrelin deletion exacerbates HFCS-induced adiposity and inflammation in adipose tissues, as well as whole-body insulin resistance. Our findings suggest that HFCS and SUC have differential effects on lipid metabolism: while sucrose promotes obesogenesis, HFCS primarily enhances inflammation and insulin resistance, and ghrelin confers protective effects for these metabolic dysfunctions.

  1. Suppression of Ghrelin Exacerbates HFCS-Induced Adiposity and Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Xiaojun Ma

    2017-06-01

    Full Text Available High fructose corn syrup (HFCS is widely used as sweetener in processed foods and soft drinks in the United States, largely substituting sucrose (SUC. The orexigenic hormone ghrelin promotes obesity and insulin resistance; ghrelin responds differently to HFCS and SUC ingestion. Here we investigated the roles of ghrelin in HFCS- and SUC-induced adiposity and insulin resistance. To mimic soft drinks, 10-week-old male wild-type (WT and ghrelin knockout (Ghrelin−/− mice were subjected to ad lib. regular chow diet supplemented with either water (RD, 8% HFCS (HFCS, or 10% sucrose (SUC. We found that SUC-feeding induced more robust increases in body weight and body fat than HFCS-feeding. Comparing to SUC-fed mice, HFCS-fed mice showed lower body weight but higher circulating glucose and insulin levels. Interestingly, we also found that ghrelin deletion exacerbates HFCS-induced adiposity and inflammation in adipose tissues, as well as whole-body insulin resistance. Our findings suggest that HFCS and SUC have differential effects on lipid metabolism: while sucrose promotes obesogenesis, HFCS primarily enhances inflammation and insulin resistance, and ghrelin confers protective effects for these metabolic dysfunctions.

  2. Nuclear technique for inducing new genetical sources of powdery mildew resistant mutants of wheat

    International Nuclear Information System (INIS)

    Shi Jinguo; Hu Xiaoyuan; Fan Qingxia; Wang Linqing; Hong Jisong

    1996-01-01

    Three varieties of winter wheat were treated with γ-rays, electron-beams, NaN 3 , EMS with various doses and intermittent irradiation of γ-rays respectively. 16 pure varieties and 12 hybrids were irradiated by γ-rays with appropriate doses (250∼300 Gy) for inducing mutation resistant to powdery mildew in winter wheat. γ-rays, electron-beams, NaN 3 and EMS were effective mutagens for inducing powdery mildew resistant mutants. The latter two were more effective than the former. It showed that the appropriate doses were as follows: γ-rays 300∼350 Gy, electron-beams 100∼200 Gy, NaN 3 1∼3 mmol/L, EMS about 0.3%. It also showed that the intermittent irradiation of γ-rays was more effective than the continuous irradiation for inducing powdery mildew resistant mutants. Irradiating hybrids were more effective materials than pure varieties for this purpose. 86 mutants with resistance to powdery mildew were obtained

  3. Edible Bird’s Nest Prevents High Fat Diet-Induced Insulin Resistance in Rats

    Directory of Open Access Journals (Sweden)

    Zhang Yida

    2015-01-01

    Full Text Available Edible bird’s nest (EBN is used traditionally in many parts of Asia to improve wellbeing, but there are limited studies on its efficacy. We explored the potential use of EBN for prevention of high fat diet- (HFD- induced insulin resistance in rats. HFD was given to rats with or without simvastatin or EBN for 12 weeks. During the intervention period, weight measurements were recorded weekly. Blood samples were collected at the end of the intervention and oral glucose tolerance test conducted, after which the rats were sacrificed and their liver and adipose tissues collected for further studies. Serum adiponectin, leptin, F2-isoprostane, insulin, and lipid profile were estimated, and homeostatic model assessment of insulin resistance computed. Effects of the different interventions on transcriptional regulation of insulin signaling genes were also evaluated. The results showed that HFD worsened metabolic indices and induced insulin resistance partly through transcriptional regulation of the insulin signaling genes. Additionally, simvastatin was able to prevent hypercholesterolemia but promoted insulin resistance similar to HFD. EBN, on the other hand, prevented the worsening of metabolic indices and transcriptional changes in insulin signaling genes due to HFD. The results suggest that EBN may be used as functional food to prevent insulin resistance.

  4. X-ray irradiation induced reversible resistance change in Pt/TiO2/Pt cells.

    Science.gov (United States)

    Chang, Seo Hyoung; Kim, Jungho; Phatak, Charudatta; D'Aquila, Kenneth; Kim, Seong Keun; Kim, Jiyoon; Song, Seul Ji; Hwang, Cheol Seong; Eastman, Jeffrey A; Freeland, John W; Hong, Seungbum

    2014-02-25

    The interaction between X-rays and matter is an intriguing topic for both fundamental science and possible applications. In particular, synchrotron-based brilliant X-ray beams have been used as a powerful diagnostic tool to unveil nanoscale phenomena in functional materials. However, it has not been widely investigated how functional materials respond to the brilliant X-rays. Here, we report the X-ray-induced reversible resistance change in 40-nm-thick TiO2 films sandwiched by Pt top and bottom electrodes, and propose the physical mechanism behind the emergent phenomenon. Our findings indicate that there exists a photovoltaic-like effect, which modulates the resistance reversibly by a few orders of magnitude, depending on the intensity of impinging X-rays. We found that this effect, combined with the X-ray irradiation induced phase transition confirmed by transmission electron microscopy, triggers a nonvolatile reversible resistance change. Understanding X-ray-controlled reversible resistance changes can provide possibilities to control initial resistance states of functional materials, which could be useful for future information and energy storage devices.

  5. Co nanoparticles induced resistive switching and magnetism for the electrochemically deposited polypyrrole composite films.

    Science.gov (United States)

    Xu, Zedong; Gao, Min; Yu, Lina; Lu, Liying; Xu, Xiaoguang; Jiang, Yong

    2014-10-22

    The resistive switching behavior of Co-nanoparticle-dispersed polypyrrole (PPy) composite films is studied. A novel design method for resistive random access memory (ReRAM) is proposed. The conducting polymer films with metal nanocrystal (NC)-dispersed carbon chains induce the spontaneous oxidization of the conducting polymer at the surface. The resistive switching behavior is achieved by an electric field controlling the oxygen ion mobility between the metal electrode and the conducting polymer film to realize the mutual transition between intrinsic conduction (low resistive state) and oxidized layer conduction (high resistive state). Furthermore, the formation process of intrinsic conductive paths can be effectively controlled in the conducting polymer ReRAM using metal NCs in films because the inner metal NCs induce electric field lines converging around them and the intensity of the electric field at the tip of NCs can greatly exceed that of the other region. Metal NCs can also bring new characteristics for ReRAM, such as magnetism by dispersing magnetic metal NCs in polymer, to obtain multifunctional electronic devices or meet some special purpose in future applications. Our works will enrich the application fields of the electromagnetic PPy composite films and present a novel material for ReRAM devices.

  6. The use of the multiple-gradient array for geoelectrical resistivity and induced polarization imaging

    Science.gov (United States)

    Aizebeokhai, Ahzegbobor P.; Oyeyemi, Kehinde D.

    2014-12-01

    The use of most conventional electrode configurations in electrical resistivity survey is often time consuming and labour intensive, especially when using manual data acquisition systems. Often, data acquisition teams tend to reduce data density so as to speed up field operation thereby reducing the survey cost; but this could significantly degrade the quality and resolution of the inverse models. In the present work, the potential of using the multiple-gradient array, a non-conventional electrode configuration, for practical cost effective and rapid subsurface resistivity and induced polarization mapping was evaluated. The array was used to conduct 2D resistivity and time-domain induced polarization imaging along two traverses in a study site at Ota, southwestern Nigeria. The subsurface was characterised and the main aquifer delineated using the inverse resistivity and chargeability images obtained. The performance of the multiple-gradient array was evaluated by correlating the 2D resistivity and chargeability images with those of the conventional Wenner array as well as the result of some soundings conducted along the same traverses using Schlumberger array. The multiple-gradient array has been found to have the advantage of measurement logistics and improved image resolution over the Wenner array.

  7. Acquisition of anoikis resistance in human osteosarcoma cells does not alter sensitivity to chemotherapeutic agents

    International Nuclear Information System (INIS)

    Díaz-Montero, C Marcela; McIntyre, Bradley W

    2005-01-01

    Chemotherapy-induced cell death can involve the induction of apoptosis. Thus, aberrant function of the pathways involved might result in chemoresistance. Since cell adhesion to the extracellular matrix acts as a survival factor that homeostatically maintains normal tissue architecture, it was tested whether acquisition of resistance to deadhesion-induced apoptosis (anoikis) in human osteosarcoma would result in resistance to chemotherapy. Osteosarcoma cell lines (SAOS-2 and TE-85) obtained from ATCC and were maintained in complete Eagle's MEM medium. Suspension culture was established by placing cells in tissue culture wells coated with poly-HEMA. Cell cytotoxicity was determined using a live/dead cytotoxicity assay. Cell cycle/apoptosis analyses were performed using propidium iodide (PI) staining with subsequent FACS analysis. Apoptosis was also assayed by Annexin-FITC/PI staining. Etoposide, adriamycin, vinblastine, cisplatin and paclitaxel were able to induce apoptosis in human osteosarcoma cells SAOS-2 regardless of their anoikis resistance phenotype or the culture conditions (adhered vs. suspended). Moreover, suspended anoikis resistant TE-85 cells (TE-85ar) retained their sensitivity to chemotherapy as well. Acquisition of anoikis resistance in human osteosarcoma cells does not result in a generalized resistance to all apoptotic stimuli, including chemotherapy. Moreover, our results suggest that the pathways regulating anoikis resistance and chemotherapy resistance might involve the action of different mediators

  8. Acquisition of anoikis resistance in human osteosarcoma cells does not alter sensitivity to chemotherapeutic agents

    Directory of Open Access Journals (Sweden)

    McIntyre Bradley W

    2005-04-01

    Full Text Available Abstract Background Chemotherapy-induced cell death can involve the induction of apoptosis. Thus, aberrant function of the pathways involved might result in chemoresistance. Since cell adhesion to the extracellular matrix acts as a survival factor that homeostatically maintains normal tissue architecture, it was tested whether acquisition of resistance to deadhesion-induced apoptosis (anoikis in human osteosarcoma would result in resistance to chemotherapy. Methods Osteosarcoma cell lines (SAOS-2 and TE-85 obtained from ATCC and were maintained in complete Eagle's MEM medium. Suspension culture was established by placing cells in tissue culture wells coated with poly-HEMA. Cell cytotoxicity was determined using a live/dead cytotoxicity assay. Cell cycle/apoptosis analyses were performed using propidium iodide (PI staining with subsequent FACS analysis. Apoptosis was also assayed by Annexin-FITC/PI staining. Results Etoposide, adriamycin, vinblastine, cisplatin and paclitaxel were able to induce apoptosis in human osteosarcoma cells SAOS-2 regardless of their anoikis resistance phenotype or the culture conditions (adhered vs. suspended. Moreover, suspended anoikis resistant TE-85 cells (TE-85ar retained their sensitivity to chemotherapy as well. Conclusion Acquisition of anoikis resistance in human osteosarcoma cells does not result in a generalized resistance to all apoptotic stimuli, including chemotherapy. Moreover, our results suggest that the pathways regulating anoikis resistance and chemotherapy resistance might involve the action of different mediators.

  9. Polychlorinated biphenyls exposure-induced insulin resistance is mediated by lipid droplet enlargement through Fsp27.

    Science.gov (United States)

    Kim, Hye Young; Kwon, Woo Young; Kim, Yeon A; Oh, Yoo Jin; Yoo, Seung Hee; Lee, Mi Hwa; Bae, Ju Yong; Kim, Jong-Min; Yoo, Young Hyun

    2017-06-01

    Although epidemiological and experimental studies demonstrated that polychlorinated biphenyls (PCBs) lead to insulin resistance, the mechanism underlying PCBs-induced insulin resistance has remained unsolved. In this study, we examined in vitro and in vivo effects of PCB-118 (dioxin-like PCB) and PCB-138 (non-dioxin-like PCB) on adipocyte differentiation, lipid droplet growth, and insulin action. 3T3-L1 adipocytes were incubated with PCB-118 or PCB-138 during adipocyte differentiation. For in vivo studies, C57BL/6 mice were administered PCB-118 or PCB-138 (37.5 mg/kg) by intraperitoneal injection and we examined adiposity and whole-body insulin action. PCB-118 and PCB-138 significantly promoted adipocyte differentiation and increased the lipid droplet (LD) size in 3T3-L1 adipocytes. In mice, both PCBs increased adipose mass and adipocyte size. Furthermore, both PCBs induced insulin resistance in vitro and in vivo. Expression of fat-specific protein 27 (Fsp27), which is localized to LD contact sites, was increased in PCB-treated 3T3-L1 adipocytes and mice. Depletion of Fsp27 by siRNA resulted in the inhibition of LD enlargement and attenuation of insulin resistance in PCB-treated 3T3-L1 adipocytes. An anti-diabetic drug, metformin, attenuated insulin resistance in PCB-treated 3T3-L1 adipocytes through the reduced expression of Fsp27 protein and LD size. This study suggests that PCB exposure-induced insulin resistance is mediated by LD enlargement through Fsp27.

  10. Lifestyle-induced metabolic inflexibility and accelerated ageing syndrome: insulin resistance, friend or foe?

    Directory of Open Access Journals (Sweden)

    Bell Jimmy D

    2009-04-01

    Full Text Available Abstract The metabolic syndrome may have its origins in thriftiness, insulin resistance and one of the most ancient of all signalling systems, redox. Thriftiness results from an evolutionarily-driven propensity to minimise energy expenditure. This has to be balanced with the need to resist the oxidative stress from cellular signalling and pathogen resistance, giving rise to something we call 'redox-thriftiness'. This is based on the notion that mitochondria may be able to both amplify membrane-derived redox growth signals as well as negatively regulate them, resulting in an increased ATP/ROS ratio. We suggest that 'redox-thriftiness' leads to insulin resistance, which has the effect of both protecting the individual cell from excessive growth/inflammatory stress, while ensuring energy is channelled to the brain, the immune system, and for storage. We also suggest that fine tuning of redox-thriftiness is achieved by hormetic (mild stress signals that stimulate mitochondrial biogenesis and resistance to oxidative stress, which improves metabolic flexibility. However, in a non-hormetic environment with excessive calories, the protective nature of this system may lead to escalating insulin resistance and rising oxidative stress due to metabolic inflexibility and mitochondrial overload. Thus, the mitochondrially-associated resistance to oxidative stress (and metabolic flexibility may determine insulin resistance. Genetically and environmentally determined mitochondrial function may define a 'tipping point' where protective insulin resistance tips over to inflammatory insulin resistance. Many hormetic factors may induce mild mitochondrial stress and biogenesis, including exercise, fasting, temperature extremes, unsaturated fats, polyphenols, alcohol, and even metformin and statins. Without hormesis, a proposed redox-thriftiness tipping point might lead to a feed forward insulin resistance cycle in the presence of excess calories. We therefore suggest

  11. Mechanisms of methicillin-resistant Staphylococcus aureus pneumonia-induced intestinal epithelial apoptosis.

    Science.gov (United States)

    Perrone, Erin E; Jung, Enjae; Breed, Elise; Dominguez, Jessica A; Liang, Zhe; Clark, Andrew T; Dunne, W Michael; Burd, Eileen M; Coopersmith, Craig M

    2012-07-01

    Methicillin-resistant Staphylococcus aureus (MRSA) pneumonia-induced sepsis is a common cause of morbidity in the intensive care unit. Although pneumonia is initiated in the lungs, extrapulmonary manifestations occur commonly. In light of the key role the intestine plays in the pathophysiology of sepsis, we sought to determine whether MRSA pneumonia induces intestinal injury. FVB/N mice were subjected to MRSA or sham pneumonia and killed 24 h later. Septic animals had a marked increase in intestinal epithelial apoptosis by both hematoxylin-eosin and active caspase 3 staining. Methicillin-resistant S. aureus-induced intestinal apoptosis was associated with an increase in the expression of the proapoptotic proteins Bid and Bax and the antiapoptotic protein Bcl-xL in the mitochondrial pathway. In the receptor-mediated pathway, MRSA pneumonia induced an increase in Fas ligand but decreased protein levels of Fas, FADD, pFADD, TNF-R1, and TRADD. To assess the functional significance of these changes, MRSA pneumonia was induced in mice with genetic manipulations in proteins in either the mitochondrial or receptor-mediated pathways. Both Bid-/- mice and animals with intestine-specific overexpression of Bcl-2 had decreased intestinal apoptosis compared with wild-type animals. In contrast, Fas ligand-/- mice had no alterations in apoptosis. To determine if these findings were organism-specific, similar experiments were performed in mice subjected to Pseudomonas aeruginosa pneumonia. Pseudomonas aeruginosa induced gut apoptosis, but unlike MRSA, this was associated with increased Bcl-2 and TNF-R1 and decreased Fas. Methicillin-resistant S. aureus pneumonia thus induces organism-specific changes in intestinal apoptosis via changes in both the mitochondrial and receptor-mediated pathways, although the former may be more functionally significant.

  12. Extracellular matrix metalloproteinase inducer enhances host resistance against pseudomonas aeruginosa infection through MAPK signaling pathway

    OpenAIRE

    Li, Yongwei; Chen, Lu; Wang, Chunxia; Chen, Jianshe; Zhang, Xiaoqian; Hu, Yue; Niu, Xiaobin; Pei, Dongxu; He, Zhiqiang; Bi, Yongyi

    2016-01-01

    This study aims to explore the role of extra-cellular matrix metalloproteinase inducer (EMMPRIN) in the drug resistance of the pseudomonas aeruginosa (PA). The BALB/c mice were transfected with PA, then the mice were infected with the siRNA of EMMPRIN to silence the EMMPRIN gene. The EMMPRIN mRNA and protein were detected by using RT-PCR and western blot, respectively. In order to examine the function of EMMPRIN in drug resistance of PA, the BALB/c and C57BL/6 mice were treated with EMMPRIN s...

  13. Reversal of diet-induced obesity and insulin resistance by inducible genetic ablation of GRK2

    NARCIS (Netherlands)

    Vila-Bedmar, Rocio; Cruces-Sande, Marta; Lucas, Elisa; Willemen, Hanneke L D M; Heijnen, Cobi J; Kavelaars, Annemieke; Mayor, Federico; Murga, Cristina

    2015-01-01

    Insulin resistance is a common feature of obesity and predisposes individuals to various prevalent pathological conditions. G protein (heterotrimeric guanine nucleotide-binding protein)-coupled receptor kinase 2 (GRK2) integrates several signal transduction pathways and is emerging as a

  14. Inducible clindamycin and methicillin resistant Staphylococcus aureus in a tertiary care hospital, Kathmandu, Nepal.

    Science.gov (United States)

    Adhikari, R P; Shrestha, S; Barakoti, A; Amatya, R

    2017-07-11

    Staphylococcus aureus, an important nosocomial pathogen, is frequently associated with infections in human. The management of the infections by it especially methicillin resistant ones is often difficult because methicillin resistant S. aureus is usually resistant to multiple antibiotics. Macrolide-lincosamide streptogramin B family of antibiotics is commonly used to treat such infections as an alternative to vancomycin. This study was conducted over the period of one and half year from November 2013-April 2015 in Microbiology laboratory of Nepal Medical College and Teaching Hospital, Kathmandu, Nepal to find the incidence of different phenotypes of MLS B resistance among S. aureus from clinical samples and their association with methicillin resistance. Two hundred seventy isolates of S. aureus were included in the study. Methicillin resistance was detected by cefoxitin disc diffusion method and inducible clindamycin resistance by erythromycin and clindamycin disc approximation test (D-test). Of the 270 clinical isolates of S. aureus, 25.1% (68/270) were MRSA. Erythromycin and clindamycin resistance was seen in 54.4% (147/270) and 41.8% (113/270) isolates respectively. Resistance to erythromycin and clindamycin were higher in MRSA as compared to MSSA (erythromycin-resistance: 88.2% Vs 39.1% and clindamycin-resistance: 79.4% Vs 41.8%). The overall prevalence of i MLS B and c MLS B phenotype was 11.48% (31/270) and 29.25% (79/270) respectively. Both i MLS B and c MLS B phenotypes predominated in MRSA strains. Detection rate of MRSA in our study shows the necessity to improve in healthcare practices and to formulate new policy for the control of MRSA infections. Clindamycin resistance in the form of i MLS B and c MLS B especially among MRSA emphasizes the need of D-test to be performed routinely in our set up while using clindamycin as an alternative choice to anti-staphylococcal antibiotics like vancomycin and linezolid in the treatment of staphylococcal infections.

  15. Molecular and biochemical characterization of an induced mutation conferring imidazolinone resistance in sunflower.

    Science.gov (United States)

    Sala, Carlos A; Bulos, Mariano; Echarte, Mariel; Whitt, Sherry R; Ascenzi, Robert

    2008-12-01

    A partially dominant nuclear gene conferring resistance to the imidazolinone herbicides was previously identified in the cultivated sunflower (Helianthus annuus L.) line CLHA-Plus developed by seed mutagenesis. The objective of this study was to characterize this resistant gene at the phenotypic, biochemical and molecular levels. CLHA-Plus showed a complete susceptibility to sulfonylureas (metsulfuron, tribenuron and chlorsulfuron) but, on the other hand, it showed a complete resistance to imidazolinones (imazamox, imazapyr and imazapic) at two rates of herbicide application. This pattern was in close association with the AHAS-inhibition kinetics of protein extracts of CLHA-Plus challenged with different doses of imazamox and chlorsulfuron. Nucleotide and deduced amino acid sequence comparisons between resistant and susceptible lines indicated that the imidazolinone-resistant AHAS of CLHA-Plus has a threonine codon (ACG) at position 122 (relative to the Arabidopsis thaliana AHAS sequence), whereas the herbicide-susceptible enzyme from BTK47 has an alanine residue (GCG) at this position. Since the resistance genes to AHAS-inhibiting herbicides so far characterized in sunflower code for the catalytic (large) subunit of AHAS, we propose to redesignate the wild type allele as ahasl1 and the incomplete dominant resistant alleles as Ahasl1-1 (previously Imr1 or Ar ( pur )), Ahasl1-2 (previously Ar ( kan )) and Ahasl1-3 (for the allele present in CLHA-Plus). The higher tolerance level to imidazolinones and the lack of cross-resistance to other AHAS-inhibiting herbicides of Ahasl1-3 indicate that this induced mutation can be used to develop commercial hybrids with superior levels of tolerance and, at the same time, to assist weed management where control of weedy common sunflower is necessary.

  16. [Study of the relationship among expression of Survivin and MRP and the drug resistance in human nasopharyngeal carcinoma].

    Science.gov (United States)

    Yang, Ning; Zhu, Lepan; Tan, Tan; Hou, Chunyan

    2015-02-01

    This study aimed to explore the relationship among expression of Survivin and MRP and drug resistance in NPC. Expression of Survivin were detected by immunohistochemistry method in 45 cases of NPC and 24 cases of normal mucous membrane of nasopharynx (NMMN). The relationship between expression of Survivin and pathological factors in NPC were analysized. Expression of Survivin and MRP were detected in 31 patients of NPC with paclitaxel resistance and 20 patients of NPC without paclitaxel resistance. The relation- ship among the expression of Survivin or MRP and paclitaxel resistance in NPC were analysized. The paclitaxel resistance cell line, 5-8F-PTX(+); was established by a step-increased method. The expression of Survivin and MRP were detected by western blot in 5-8F-PTX(+) and 5-8F. The positive were 71. 1% (32/45) in NPC and 8.33% (2/24) in NMMN. And there were significantly differences between them (P MRP were 87.1% (27/31) in NPC patients with paclitaxel resistance and 40.0% (8/20) in NPC patients without paclitaxel resistance, respectively. There were significantly differences between them (P MRP in NPC patients with Paclitaxel resistance. The expression of Survivin and MRP were higher in 5-8F-PTX(+) than in 5-8F. The IC50 of paclitaxel, cDDP, 5-FU and Vincristine were significantly higher in 5-8F-PTX(+) than in 5-8F. There were relationship among the expression of Survivin and difference, metastasis and TNM stages of NPC. Survivin may serves as a molecular marker for development and progress in NPC. There were relationship among the high expression of Survivin and MRP and increasing of drug resistance in NPC.

  17. Photo-induced current transient spectroscopy for high-resistivity neutron-transmutation-doped silicon

    International Nuclear Information System (INIS)

    Tokuda, Yutaka; Inoue, Yajiro; Usami, Akira

    1987-01-01

    Defects in high-resistivity neutron-transmutation-doped (NTD) silicon prior to annealing were studied by photo-induced current transient spectroscopy (PICTS). The thermal-neutron fluence was 9.5 x 10 17 cm -2 to give a resistivity of about 30 Ω after annealing, and the fast-neutron fluence was 9.5 x 10 16 cm -2 . Four traps with thermal emission activation energies of 0.15, 0.41. 0.47 and 0.50 eV were observed in NTD silicon. A trap with the thermal emission activation energy of 0.15 eV was considered to correspond to the divacancy. Although the clustered nature of the defects was observed, PICTS measurements suggest that the material state of high-resistivity NTD silicon is still crystalline and not amorphous. (author)

  18. Fluxon induced surface resistance and field emission in niobium films at 1.5 GHz

    CERN Document Server

    Benvenuti, Cristoforo; Darriulat, Pierre; Peck, M A; Valente, A M; Van't Hof, C A

    2001-01-01

    The surface resistance of superconducting niobium films induced by the presence of trapped magnetic flux, presumably in the form of a pinned fluxon lattice, is shown to be modified by the presence of a field emitting impurity or defect. The modification takes the form of an additional surface resistance proportional to the density of the fluxon lattice and increasing linearly with the amplitude of the microwave above a threshold significantly lower than the field emission threshold. Such an effect, a precursor of electron emission, is observed for the first time in a study using radiofrequency cavities operating at their fundamental 1.5 GHz frequency. The measured properties of the additional surface resistance severely constrain possible explanations of the observed effect. (23 refs).

  19. Evaluation of induced mutants of wheat for resistance to fungal diseases

    International Nuclear Information System (INIS)

    Barriga B, P.; Fuentes P, R.; Andrade S, N.; Seeman F, P.

    1990-01-01

    Evaluation of induced mutants of wheat for resistance to fungal diseases. Seeds of spring wheat cultivars Austral and Huenufen were exposed to gamma radiation in doses of 0.10 and 0.25 KGy with the objective of producing genotypes resistant to the main fungal diseases, with a high protein content and grain yield, for the southern region of Chile (39 sup(o)-44 sup(o) Latitude south). The selection process and evaluation up to the generation M sub(8) has made possible to identify mutants with a higher protein content and grain yield. Progress made in improving resistance to Puccinia striiformis and tolerance to Septoria spp., has also been important. Some selected mutants, conditioned to their future performance, could be directly used as commercial varieties and other mutants, on crosses with regionally adapted cultivars. (author)

  20. Studies on productivity lodge resistance of radiation induced mutants of syrian local durum wheat

    Energy Technology Data Exchange (ETDEWEB)

    Elfares, A M; Ghazal, H M [Dep. of Radiation Agriculture, Syrian Atomic Energy Commision, Damascus, P.O. Box 6091, (Syrian Arab Republic)

    1995-10-01

    The aim of the research was to induce mutations characterized by lodging resistant and high yielding ability in two syrian local durum wheat land races. This research was carried out at two periods during 1983-1987 and from 1991-1993. At the first period, Kernels of Hourani and Senatore Cappelle were treated with 10, 15, 20, 25 and 30 K rad of gamma rays at the Laboratory of the commission of Syrian Atomic Energy to induce mutations. The treated Kernels were planted in 1983/1984 season. After that, selection were practicised on plants which characterized by good performance and lodging resistant. During the successive seasons, screening were made on mutant lines to keep out only lines which show adaptability to intensive cultivation. Second period includes testing of selected lines at two govern orates of syria (Raqqa and Aleppo) during three successive seasons; 1991/1992 and 1992/1993 under intensive cultivation conditions (fertilization, irrigation, stands, etc.).

  1. INDUCING RESISTANCE IN COTTON AGAINST COLLETOTRICHUM GOSSYPII VAR. CEPHALOSPORIOIDES WITH ESSENTIAL OILS

    Directory of Open Access Journals (Sweden)

    B. T. Santos

    2016-11-01

    Full Text Available This study aimed to evaluate the potential of essential oils of rosemary (Rosmarinus officinalis, baccharis (Baccharis trimera, lemon grass (Cymbopogon citratus, basil (Ocimum basilicum and eucalyptus (Corymbia citriodora in inducing resistance in cotton plants against C. gossypii var. cephalosporioides. The inductive effect of the essential oils was evaluated in plants growing in pots in the environment, which were treated with 1% essential oil at 47 days of age. 24 hours after elicitor treatment the plants were inoculated with a suspension of 1.5 x 105 conidia mL-1 of C. gossypii var. cephalosporioides. Five evaluations were performed disease and calculated the area under the disease progress curve. All essential oils showed potential for inducing resistance against cotton C. gossypii var. cephalosporioides.

  2. Imidacloprid does not induce Cyp genes involved in insecticide resistance of a mutant Drosophila melanogaster line.

    Science.gov (United States)

    Kalajdzic, Predrag; Markaki, Maria; Oehler, Stefan; Savakis, Charalambos

    2013-10-01

    Certain xenobiotics have the capacity to induce the expression of genes involved in various biological phenomena, including insecticide resistance. The induction potential of different chemicals, among them different insecticides, has been documented for a number of insect species. In this study, we have analyzed the induction potential of Imidacloprid, a widely used member of the neonicotinoid insecticide family. Genes Cyp6g1 and Cyp6a2, known to be involved in the resistance of mutant Drosophila melanogaster line MiT[W⁻]3R2 to Imidacloprid and DDT were included in the analyzed sample. We find that Imidacloprid does not induce expression of the analyzed genes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Root-Expressed Maize Lipoxygenase 3 Negatively Regulates Induced Systemic Resistance to Colletotrichum graminicola in Shoots

    Directory of Open Access Journals (Sweden)

    Nasie eConstantino

    2013-12-01

    Full Text Available We have previously reported that disruption of a maize root-expressed 9-lipoxygenase (9-LOX gene, ZmLOX3, results in dramatic increase in resistance to diverse leaf and stalk pathogens. Despite evident economic significance of these findings, the mechanism behind this increased resistance remained elusive. In this study, we show that increased resistance of the lox3-4 mutants is due to constitutive activation of induced systemic resistance (ISR signaling. We showed that ZmLOX3 lacked expression in leaves in response to anthracnose leaf blight pathogen Colletotrichum graminicola, but was expressed constitutively in the roots, thus prompting our hypothesis: the roots of lox3-4 mutants are the source of increased resistance in leaves. Supporting this hypothesis, treatment of wild-type plants (WT with xylem sap of lox3-4 mutant induced resistance to C. graminicola to the levels comparable to those observed in lox3-4 mutant. Moreover, treating mutants with the sap collected from WT plants partially restored the susceptibility to C. graminicola. lox3-4 mutants showed primed defense responses upon infection, which included earlier and greater induction of defense-related PAL and GST genes compared to WT. In addition to the greater expression of the octadecanoid pathway genes, lox3-4 mutant responded earlier and with a greater accumulation of H2O2 in response to C. graminicola infection or treatment with alamethicin. These findings suggest that lox3-4 mutants display constitutive ISR-like signaling. In support of this idea, root colonization by Trichoderma virens strain GV29-8 induced the same level of disease resistance in WT as the treatment with the mutant sap, but had no additional resistance effect in lox3-4 mutant. While treatment with T. virens GV29 strongly and rapidly suppressed ZmLOX3 expression in hydroponically grown WT roots, T. virens Δsml mutant, which is deficient in ISR induction, was unable to suppress expression of ZmLOX3, thus

  4. Molecular Detection of Inducible Clindamycin Resistance among Staphylococcal Strains Isolated from Hospital Patients

    Directory of Open Access Journals (Sweden)

    Shadiyeh Abdollahi

    2013-04-01

    Full Text Available Background & Objectives: Macrolide, lincosamide and streptogramin B (MLSB antimicrobial agents are used in the treatment of staphylococcal infections. They prevent the microbial protein synthesis system through binding to 23 S rRNA. The aim of this study was to apply molecular methods to detect inducible clindamycin resistance genes among staphylococcal strains isolated from clinical specimens.   Methods : Two hundred staphylococcus strains were isolated from nose and throat swabs of patients in Toohid and Besat hospitals in Sanandaj . Antimicrobial susceptibilities of isolates were determined using disc diffusion method, agar screen test and D-Test. A multiplex PCR was performed using primers specific for erm (A, B, C, TR genes.   Results: Out of 200 isolates, 18.5 % were MRSA and 32% were MRCNS (methicillin resistant coagulase negative staphylococci. Of 80 erythromycin resistant isolates, 48 were coagulase negative and 32 were S. aureus. Among the 48 coagulase negative staphylococci (CONS isolates, 11.63% expressed the MLSB-inducible phenotypes. Using PCR, the frequency of different genes in the collection of isolates were as follows: ermA 5.41 % , erm B 5.41 % , and erm C 3.13%. The ermTR gene was negative in all isolates. Among the 32 S. aureus isolates, 9.38% expressed the MLSB-nducible phenotype. Using PCR, these isolates harbored erm A (2.22%, ermB (2.22%, ermC (2.22% and ermTR (2.22% .   Conclusion: This is the first study to show the rate of inducible clindamycin clinical isolates of staphylococci harboring erm genes in Sananadaj. It also demonstrated the frequency of erm genes was higher among CONS isolates than S. aureus. This data suggested the transfer of resistance gene from nonpathogenic to pathogenic strains is likely to happen. Therefore, screening and control of these resistance genes is recommended at clinical laboratories.

  5. High Uric Acid Induces Insulin Resistance in Cardiomyocytes In Vitro and In Vivo.

    Directory of Open Access Journals (Sweden)

    Li Zhi

    Full Text Available Clinical studies have shown hyperuricemia strongly associated with insulin resistance as well as cardiovascular disease. Direct evidence of how high uric acid (HUA affects insulin resistance in cardiomyocytes, but the pathological mechanism of HUA associated with cardiovascular disease remains to be clarified. We aimed to examine the effect of HUA on insulin sensitivity in cardiomyocytes and on insulin resistance in hyperuricemic mouse model. We exposed primary cardiomyocytes and a rat cardiomyocyte cell line, H9c2 cardiomyocytes, to HUA, then quantified glucose uptake with a fluorescent glucose analog, 2-NBDG, after insulin challenge and detected reactive oxygen species (ROS production. Western blot analysis was used to examine the levels of insulin receptor (IR, phosphorylated insulin receptor substrate 1 (IRS1, Ser307 and phospho-Akt (Ser473. We monitored the impact of HUA on insulin resistance, insulin signaling and IR, phospho-IRS1 (Ser307 and phospho-Akt levels in myocardial tissue of an acute hyperuricemia mouse model established by potassium oxonate treatment. HUA inhibited insulin-induced glucose uptake in H9c2 and primary cardiomyocytes. It increased ROS production; pretreatment with N-acetyl-L-cysteine (NAC, a ROS scavenger, reversed HUA-inhibited glucose uptake induced by insulin. HUA exposure directly increased the phospho-IRS1 (Ser307 response to insulin and inhibited that of phospho-Akt in H9C2 cardiomyocytes, which was blocked by NAC. Furthermore, the acute hyperuricemic mice model showed impaired glucose tolerance and insulin tolerance accompanied by increased phospho-IRS1 (Ser307 and inhibited phospho-Akt response to insulin in myocardial tissues. HUA inhibited insulin signaling and induced insulin resistance in cardiomyocytes in vitro and in vivo, which is a novel potential mechanism of hyperuricemic-related cardiovascular disease.

  6. Carbon-Starvation Induces Cross-Resistance to Thermal, Acid, and Oxidative Stress in Serratia marcescens

    Science.gov (United States)

    Pittman, Joseph R.; Kline, La’Kesha C.; Kenyon, William J.

    2015-01-01

    The broad host-range pathogen Serratia marcescens survives in diverse host and non-host environments, often enduring conditions in which the concentration of essential nutrients is growth-limiting. In such environments, carbon and energy source starvation (carbon-starvation) is one of the most common forms of stress encountered by S. marcescens. Related members of the family Enterobacteriaceae are known to undergo substantial changes in gene expression and physiology in response to the specific stress of carbon-starvation, enabling non-spore-forming cells to survive periods of prolonged starvation and exposure to other forms of stress (i.e., starvation-induced cross-resistance). To determine if carbon-starvation also results in elevated levels of cross-resistance in S. marcescens, both log-phase and carbon-starved cultures, depleted of glucose before the onset of high cell-density stationary-phase, were grown in minimal media at either 30 °C or 37 °C and were then challenged for resistance to high temperature (50 °C), low pH (pH 2.8), and oxidative stress (15 mM H2O2). In general, carbon-starved cells exhibited a higher level of resistance to thermal stress, acid stress, and oxidative stress compared to log-phase cells. The extent of carbon-starvation-induced cross-resistance was dependent on incubation temperature and on the particular strain of S. marcescens. In addition, strain- and temperature-dependent variations in long-term starvation survival were also observed. The enhanced stress-resistance of starved S. marcescens cells could be an important factor in their survival and persistence in many non-host environments and within certain host microenvironments where the availability of carbon sources is suboptimal for growth. PMID:27682115

  7. Carbon-Starvation Induces Cross-Resistance to Thermal, Acid, and Oxidative Stress in Serratia marcescens

    Directory of Open Access Journals (Sweden)

    Joseph R. Pittman

    2015-10-01

    Full Text Available The broad host-range pathogen Serratia marcescens survives in diverse host and non-host environments, often enduring conditions in which the concentration of essential nutrients is growth-limiting. In such environments, carbon and energy source starvation (carbon-starvation is one of the most common forms of stress encountered by S. marcescens. Related members of the family Enterobacteriaceae are known to undergo substantial changes in gene expression and physiology in response to the specific stress of carbon-starvation, enabling non-spore-forming cells to survive periods of prolonged starvation and exposure to other forms of stress (i.e., starvation-induced cross-resistance. To determine if carbon-starvation also results in elevated levels of cross-resistance in S. marcescens, both log-phase and carbon-starved cultures, depleted of glucose before the onset of high cell-density stationary-phase, were grown in minimal media at either 30 °C or 37 °C and were then challenged for resistance to high temperature (50 °C, low pH (pH 2.8, and oxidative stress (15 mM H2O2. In general, carbon-starved cells exhibited a higher level of resistance to thermal stress, acid stress, and oxidative stress compared to log-phase cells. The extent of carbon-starvation-induced cross-resistance was dependent on incubation temperature and on the particular strain of S. marcescens. In addition, strain- and temperature-dependent variations in long-term starvation survival were also observed. The enhanced stress-resistance of starved S. marcescens cells could be an important factor in their survival and persistence in many non-host environments and within certain host microenvironments where the availability of carbon sources is suboptimal for growth.

  8. Long-term characterization of the diet-induced obese and diet-resistant rat model

    DEFF Research Database (Denmark)

    Madsen, Andreas Nygaard; Hansen, Gitte; Paulsen, Sarah Juel

    2010-01-01

    , namely the selectively bred diet-induced obese (DIO) and diet-resistant (DR) rat strains. We show that they constitute useful models of the human obesity syndrome. DIO and DR rats were fed either a high-energy (HE) or a standard chow (Chow) diet from weaning to 9 months of age. Metabolic characterization......, the results underscore the effectiveness of GLP-1 mimetics both as anti-diabetes and anti-obesity agents....

  9. Influence of resistivity on energetic trapped particle-induced internal kink modes

    International Nuclear Information System (INIS)

    Biglari, H.; Chen, L.

    1986-01-01

    The influence of resistivity on energetic trapped particle-induced internal kink modes, dubbed ''fishbones'' in the literature, is explored. A general dispersion relation, which recovers the ideal theory in its appropriate limit, is derived and analyzed. An important implication of the theory for present generation fusion devices such as the Joint European Torus [Plasma Physics and Controlled Nuclear Fusion Research (IAEA, London, 1984), Vol I, p.11] is that they will be stable to fishbone activity

  10. The effect of spin induced magnetization on Jeans instability of viscous and resistive quantum plasma

    International Nuclear Information System (INIS)

    Sharma, Prerana; Chhajlani, R. K.

    2014-01-01

    The effect of spin induced magnetization and electrical resistivity incorporating the viscosity of the medium is examined on the Jeans instability of quantum magnetoplasma. Formulation of the system is done by using the quantum magnetohydrodynamic model. The analysis of the problem is carried out by normal mode analysis theory. The general dispersion relation is derived from set of perturbed equations to analyse the growth rate and condition of self-gravitational Jeans instability. To discuss the influence of resistivity, magnetization, and viscosity parameters on Jeans instability, the general dispersion relation is reduced for both transverse and longitudinal mode of propagations. In the case of transverse propagation, the gravitating mode is found to be affected by the viscosity, magnetization, resistivity, and magnetic field strength whereas Jeans criterion of instability is modified by the magnetization and quantum parameter. In the longitudinal mode of propagation, the gravitating mode is found to be modified due to the viscosity and quantum correction in which the Jeans condition of instability is influenced only by quantum parameter. The other non-gravitating Alfven mode in this direction is affected by finite electrical resistivity, spin induced magnetization, and viscosity. The numerical study for the growth rate of Jeans instability is carried out for both in the transverse and longitudinal direction of propagation to the magnetic field. The effect of various parameters on the growth rate of Jeans instability in quantum plasma is analysed

  11. Host-Induced Silencing of Pathogenicity Genes Enhances Resistance to Fusarium oxysporum Wilt in Tomato.

    Science.gov (United States)

    Bharti, Poonam; Jyoti, Poonam; Kapoor, Priya; Sharma, Vandana; Shanmugam, V; Yadav, Sudesh Kumar

    2017-08-01

    This study presents a novel approach of controlling vascular wilt in tomato by RNAi expression directed to pathogenicity genes of Fusarium oxysporum f. sp. lycopersici. Vascular wilt of tomato caused by Fusarium oxysporum f. sp. lycopersici leads to qualitative and quantitative loss of the crop. Limitation in the existing control measures necessitates the development of alternative strategies to increase resistance in the plants against pathogens. Recent findings paved way to RNAi, as a promising method for silencing of pathogenicity genes in fungus and provided effective resistance against fungal pathogens. Here, two important pathogenicity genes FOW2, a Zn(II)2Cys6 family putative transcription regulator, and chsV, a putative myosin motor and a chitin synthase domain, were used for host-induced gene silencing through hairpinRNA cassettes of these genes against Fusarium oxysporum f. sp. lycopersici. HairpinRNAs were assembled in appropriate binary vectors and transformed into tomato plant targeting FOW2 and chsV genes, for two highly pathogenic strains of Fusarium oxysporum viz. TOFOL-IHBT and TOFOL-IVRI. Transgenic tomatoes were analyzed for possible attainment of resistance in transgenic lines against fungal infection. Eight transgenic lines expressing hairpinRNA cassettes showed trivial disease symptoms after 6-8 weeks of infection. Hence, the host-induced posttranscriptional gene silencing of pathogenicity genes in transgenic tomato plants has enhanced their resistance to vascular wilt disease caused by Fusarium oxysporum.

  12. Transient, heat-induced thermal resistance in the small intestine of mouse

    International Nuclear Information System (INIS)

    Hume, S.P.; Marigold, J.C.L.

    1980-01-01

    Heat-induced thermal resistance has been investigated in mouse jejunum by assaying crypt survival 24 h after treatment. Hyperthermia was achieved by immersing an exteriorized loop of intestine in a bath of Krebs-Ringer solution. Two approaches have been used. In the first, thermal survival curves were obtained following single hyperthermal treatments at temperatures in the range 42 to 44 0 C. Transient thermal resistance, inducted by a plateau in the crypt survival curve, developed during heating at temperatures around 42.5 0 C after 60 to 80 min. In the second series of experiments, a priming heat treatment (40.0, 41.0, 41.5, or 42.0 0 C for 60 min) was followed at varying intervals by a test treatment at 43.0 0 C. A transient resistance to the second treatment was induced, the extent and time of development being dependent upon the priming treatment. Crypt survival curves for thermally resistant intestine showed an increase in thermal D 0 and a decrease in n compared with curves from previously unheated intestine

  13. Odontella aurita-enriched diet prevents high fat diet-induced liver insulin resistance.

    Science.gov (United States)

    Amine, Hamza; Benomar, Yacir; Haimeur, Adil; Messaouri, Hafida; Meskini, Nadia; Taouis, Mohammed

    2016-01-01

    The beneficial effect of polyunsaturated omega-3 fatty acid (w-3 FA) consumption regarding cardiovascular diseases, insulin resistance and inflammation has been widely reported. Fish oil is considered as the main source of commercialized w-3 FAs, and other alternative sources have been reported such as linseed or microalgae. However, despite numerous reports, the underlying mechanisms of action of w-3 FAs on insulin resistance are still not clearly established, especially those from microalgae. Here, we report that Odontella aurita, a microalga rich in w-3 FAs eicosapentaenoic acid, prevents high fat diet-induced insulin resistance and inflammation in the liver of Wistar rats. Indeed, a high fat diet (HFD) increased plasma insulin levels associated with the impairment of insulin receptor signaling and the up-regulation of toll-like receptor 4 (TLR4) expressions. Importantly, Odontella aurita-enriched HFD (HFOA) reduces body weight and plasma insulin levels and maintains normal insulin receptor expression and responsiveness. Furthermore, HFOA decreased TLR4 expression, JNK/p38 phosphorylation and pro-inflammatory factors. In conclusion, we demonstrate for the first time, to our knowledge, that diet supplementation with whole Ondontella aurita overcomes HFD-induced insulin resistance through the inhibition of TLR4/JNK/p38 MAP kinase signaling pathways. © 2016 Society for Endocrinology.

  14. The tobacco smoke component acrolein induces glucocorticoid resistant gene expression via inhibition of histone deacetylase.

    Science.gov (United States)

    Randall, Matthew J; Haenen, Guido R M M; Bouwman, Freek G; van der Vliet, Albert; Bast, Aalt

    2016-01-05

    Chronic obstructive pulmonary disease (COPD) is the leading cause of cigarette smoke-related death worldwide. Acrolein, a crucial reactive electrophile found in cigarette smoke mimics many of the toxic effects of cigarette smoke-exposure in the lung. In macrophages, cigarette smoke is known to hinder histone deacetylases (HDACs), glucocorticoid-regulated enzymes that play an important role in the pathogenesis of glucocorticoid resistant inflammation, a common feature of COPD. Thus, we hypothesize that acrolein plays a role in COPD-associated glucocorticoid resistance. To examine the role of acrolein on glucocorticoid resistance, U937 monocytes, differentiated with PMA to macrophage-like cells were treated with acrolein for 0.5h followed by stimulation with hydrocortisone for 8h, or treated simultaneously with LPS and hydrocortisone for 8h without acrolein. GSH and nuclear HDAC activity were measured, or gene expression was analyzed by qPCR. Acrolein-mediated TNFα gene expression was not suppressed by hydrocortisone whereas LPS-induced TNFα expression was suppressed. Acrolein also significantly inhibited nuclear HDAC activity in macrophage-like cells. Incubation of recombinant HDAC2 with acrolein led to the formation of an HDAC2-acrolein adduct identified by mass spectrometry. Therefore, these results suggest that acrolein-induced inflammatory gene expression is resistant to suppression by the endogenous glucocorticoid, hydrocortisone. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. Different Proteomics of Ca2+ on SA-induced Resistance to Botrytis cinerea in Tomato

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    Linlin Li

    2016-05-01

    Full Text Available This study aims to comprehensively study the effects of Ca2+ on the SA-induced resistance Botrytis cinerea in tomato through proteomics analysis. A proteomic approach was used to uncover the inducible proteins of tomato in the susceptible tomato cultivars ‘L402’ against Botrytis cinerea after salicylic acid (SA and a combination treatment of CaCl2 and SA. The results showed that the use of combination treatment of CaCl2 and SA significantly enhanced tomato resistance against Botrytis cinerea. In total, 46 differentially expressed protein spots from 2-DE gel maps were detected, of which 41 were identified by mass spectrometry. All the identified proteins were categorized into eight groups according to their putative functions: defense response (14.00%, antioxidative protein (9.75%, photosynthesis (24.39%, molecular chaperone (4.88%, energy (17.01%, metabolism (21.95%, protein synthesis (4.88% and signal transduction (0.2%. Of the proteins in the eight function groups, the effect of stress/defense and reactive oxygen species on Ca2+-regulated SA-induced resistance may be the most important one in induced resistance by RT-PCR. The expression level of pathogenesis-related proteins (PRs and chitinase was upregulated by a combination treatment of CaCl2 and SA. The characterization of these proteins greatly helped to reveal the induced proteins involved in the regulation of Ca2+ on SA-induced resistance to Botrytis cinerea. In the combination treatment of CaCl2 and SA, the defense response and antioxidative protein were clearly upregulated much more than SA alone or the control treatment by the method of proteomics and RT-PCR. The present findings suggest that susceptible tomato cultivars treated by the combination treatment of CaCl2 and SA might possess a more sensitive SA signaling system or effective pathway than SA treatment alone. In addition, results indicated that SA could coordinate other cellular activities linked with photosynthesis and

  16. Nab-paclitaxel, docetaxel, or solvent-based paclitaxel in metastatic breast cancer: a cost-utility analysis from a Chinese health care perspective

    Directory of Open Access Journals (Sweden)

    Dranitsaris G

    2015-05-01

    Full Text Available George Dranitsaris,1 Bo Yu,2 Jennifer King,3 Satyin Kaura,3 Adams Zhang3 1Augmentium Pharma Consulting Inc., Toronto, ON, Canada; 2Fudan University Shanghai Cancer Center, Shanghai, People's Republic of China; 3Celgene Corporation, Summit, NJ, USA Background: Paclitaxel and docetaxel are commonly used for metastatic breast cancer in the People’s Republic of China. To improve the safety and efficacy of paclitaxel, an albumin-bound formulation (nab is now available in the People's Republic of China (Abraxane®. To provide health economic data for the key stakeholders, a cost-utility analysis comparing nab-paclitaxel to docetaxel, both as alternatives to paclitaxel, was conducted. Methods: A meta-analysis of clinical outcomes Phase III trials comparing nab-paclitaxel (260 mg/m2 every [q] 3 weeks or branded docetaxel (100 mg/m2 q 3 weeks, to solvent-based branded paclitaxel (175 mg/m2 q 3 weeks was undertaken to provide safety and clinical data. Resource use data for the delivery of anticancer therapy and for the treatment of grade 3/4 toxicity was collected from a time and motion study conducted in three Chinese cancer centers and from a survey of clinicians. Using the Time Trade-Off technique, health utility estimates were derived from interviewing 28 breast cancer patients from one cancer center in the People's Republic of China. All costs were reported in 2014 US dollars. Results: Nab-paclitaxel had the most favorable safety profile, characterized with the lowest incidence of grade 3/4 neutropenia, febrile neutropenia, anemia, and stomatitis. When the median number of cycles delivered from the clinical trials was applied, nab-paclitaxel had a cost per course of $19,752 compared with $8,940 and $13,741 for paclitaxel and docetaxel, respectively. As an alternative to paclitaxel, the cost per quality-adjusted life-year (QALY gained with nab-paclitaxel suggested better value than with docetaxel ($57,900 vs $130,600. Conclusion: Nab-paclitaxel

  17. Analysis of Clonostachys rosea-induced resistance to tomato gray mold disease in tomato leaves.

    Directory of Open Access Journals (Sweden)

    Liana Dalcantara Ongouya Mouekouba

    Full Text Available Tomato gray mold disease, caused by Botrytis cinerea, is a serious disease in tomato. Clonostachys rosea is an antagonistic microorganism to B. cinerea. To investigate the induced resistance mechanism of C. rosea, we examined the effects of these microorganisms on tomato leaves, along with changes in the activities of three defense enzymes (PAL, PPO, GST, second messengers (NO, H2O2, O2(- and phytohormones (IAA, ABA, GA3, ZT, MeJA, SA and C2H4. Compared to the control, all treatments induced higher levels of PAL, PPO and GST activity in tomato leaves and increased NO, SA and GA3 levels. The expression of WRKY and MAPK, two important transcription factors in plant disease resistance, was upregulated in C. rosea- and C. rosea plus B. cinerea-treated samples. Two-dimensional gel electrophoresis analysis showed that two abundant proteins were present in the C. rosea plus B. cinerea-treated samples but not in the other samples. These proteins were determined (by mass spectrum analysis to be LEXYL2 (β-xylosidase and ATP synthase CF1 alpha subunit. Therefore, C. rosea plus B. cinerea treatment induces gray mold resistance in tomato. This study provides a basis for elucidating the mechanism of C. rosea as a biocontrol agent.

  18. Celastrol Protects against Antimycin A-Induced Insulin Resistance in Human Skeletal Muscle Cells

    Directory of Open Access Journals (Sweden)

    Mohamad Hafizi Abu Bakar

    2015-05-01

    Full Text Available Mitochondrial dysfunction and inflammation are widely accepted as key hallmarks of obesity-induced skeletal muscle insulin resistance. The aim of the present study was to evaluate the functional roles of an anti-inflammatory compound, celastrol, in mitochondrial dysfunction and insulin resistance induced by antimycin A (AMA in human skeletal muscle cells. We found that celastrol treatment improved insulin-stimulated glucose uptake activity of AMA-treated cells, apparently via PI3K/Akt pathways, with significant enhancement of mitochondrial activities. Furthermore, celastrol prevented increased levels of cellular oxidative damage where the production of several pro-inflammatory cytokines in cultures cells was greatly reduced. Celastrol significantly increased protein phosphorylation of insulin signaling cascades with amplified expression of AMPK protein and attenuated NF-κB and PKC θ activation in human skeletal muscle treated with AMA. The improvement of insulin signaling pathways by celastrol was also accompanied by augmented GLUT4 protein expression. Taken together, these results suggest that celastrol may be advocated for use as a potential therapeutic molecule to protect against mitochondrial dysfunction-induced insulin resistance in human skeletal muscle cells.

  19. IFN-gamma-inducible Irga6 mediates host resistance against Chlamydia trachomatis via autophagy.

    Directory of Open Access Journals (Sweden)

    Munir A Al-Zeer

    Full Text Available Chlamydial infection of the host cell induces Gamma interferon (IFNgamma, a central immunoprotector for humans and mice. The primary defense against Chlamydia infection in the mouse involves the IFNgamma-inducible family of IRG proteins; however, the precise mechanisms mediating the pathogen's elimination are unknown. In this study, we identify Irga6 as an important resistance factor against C. trachomatis, but not C. muridarum, infection in IFNgamma-stimulated mouse embryonic fibroblasts (MEFs. We show that Irga6, Irgd, Irgm2 and Irgm3 accumulate at bacterial inclusions in MEFs upon stimulation with IFNgamma, whereas Irgb6 colocalized in the presence or absence of the cytokine. This accumulation triggers a rerouting of bacterial inclusions to autophagosomes that subsequently fuse to lysosomes for elimination. Autophagy-deficient Atg5-/- MEFs and lysosomal acidification impaired cells surrender to infection. Irgm2, Irgm3 and Irgd still localize to inclusions in IFNgamma-induced Atg5-/- cells, but Irga6 localization is disrupted indicating its pivotal role in pathogen resistance. Irga6-deficient (Irga6-/- MEFs, in which chlamydial growth is enhanced, do not respond to IFNgamma even though Irgb6, Irgd, Irgm2 and Irgm3 still localize to inclusions. Taken together, we identify Irga6 as a necessary factor in conferring host resistance by remodelling a classically nonfusogenic intracellular pathogen to stimulate fusion with autophagosomes, thereby rerouting the intruder to the lysosomal compartment for destruction.

  20. Drought and flooding have distinct effects on herbivore-induced responses and resistance in Solanum dulcamara.

    Science.gov (United States)

    Nguyen, Duy; D'Agostino, Nunzio; Tytgat, Tom O G; Sun, Pulu; Lortzing, Tobias; Visser, Eric J W; Cristescu, Simona M; Steppuhn, Anke; Mariani, Celestina; van Dam, Nicole M; Rieu, Ivo

    2016-07-01

    In the field, biotic and abiotic stresses frequently co-occur. As a consequence, common molecular signalling pathways governing adaptive responses to individual stresses can interact, resulting in compromised phenotypes. How plant signalling pathways interact under combined stresses is poorly understood. To assess this, we studied the consequence of drought and soil flooding on resistance of Solanum dulcamara to Spodoptera exigua and their effects on hormonal and transcriptomic profiles. The results showed that S. exigua larvae performed less well on drought-stressed plants than on well-watered and flooded plants. Both drought and insect feeding increased abscisic acid and jasmonic acid (JA) levels, whereas flooding did not induce JA accumulation. RNA sequencing analyses corroborated this pattern: drought and herbivory induced many biological processes that were repressed by flooding. When applied in combination, drought and herbivory had an additive effect on specific processes involved in secondary metabolism and defence responses, including protease inhibitor activity. In conclusion, drought and flooding have distinct effects on herbivore-induced responses and resistance. Especially, the interaction between abscisic acid and JA signalling may be important to optimize plant responses to combined drought and insect herbivory, making drought-stressed plants more resistant to insects than well-watered and flooded plants. © 2016 John Wiley & Sons Ltd.

  1. Effects of fatigue induced damage on the longitudinal fracture resistance of cortical bone.

    Science.gov (United States)

    Fletcher, Lloyd; Codrington, John; Parkinson, Ian

    2014-07-01

    As a composite material, cortical bone accumulates fatigue microdamage through the repetitive loading of everyday activity (e.g. walking). The accumulation of fatigue microdamage is thought to contribute to the occurrence of fragility fractures in older people. Therefore it is beneficial to understand the relationship between microcrack accumulation and the fracture resistance of cortical bone. Twenty longitudinally orientated compact tension fracture specimens were machined from a single bovine femur, ten specimens were assigned to both the control and fatigue damaged groups. The damaged group underwent a fatigue loading protocol to induce microdamage which was assessed via fluorescent microscopy. Following fatigue loading, non-linear fracture resistance tests were undertaken on both the control and damaged groups using the J-integral method. The interaction of the crack path with the fatigue induced damage and inherent toughening mechanisms were then observed using fluorescent microscopy. The results of this study show that fatigue induced damage reduces the initiation toughness of cortical bone and the growth toughness within the damage zone by three distinct mechanisms of fatigue-fracture interaction. Further analysis of the J-integral fracture resistance showed both the elastic and plastic component were reduced in the damaged group. For the elastic component this was attributed to a decreased number of ligament bridges in the crack wake while for the plastic component this was attributed to the presence of pre-existing fatigue microcracks preventing energy absorption by the formation of new microcracks.

  2. Coconut Oil Aggravates Pressure Overload-Induced Cardiomyopathy without Inducing Obesity, Systemic Insulin Resistance, or Cardiac Steatosis

    Directory of Open Access Journals (Sweden)

    Ilayaraja Muthuramu

    2017-07-01

    Full Text Available Studies evaluating the effects of high-saturated fat diets on cardiac function are most often confounded by diet-induced obesity and by systemic insulin resistance. We evaluated whether coconut oil, containing C12:0 and C14:0 as main fatty acids, aggravates pressure overload-induced cardiomyopathy induced by transverse aortic constriction (TAC in C57BL/6 mice. Mortality rate after TAC was higher (p < 0.05 in 0.2% cholesterol 10% coconut oil diet-fed mice than in standard chow-fed mice (hazard ratio 2.32, 95% confidence interval 1.16 to 4.64 during eight weeks of follow-up. The effects of coconut oil on cardiac remodeling occurred in the absence of weight gain and of systemic insulin resistance. Wet lung weight was 1.76-fold (p < 0.01 higher in coconut oil mice than in standard chow mice. Myocardial capillary density (p < 0.001 was decreased, interstitial fibrosis was 1.88-fold (p < 0.001 higher, and systolic and diastolic function was worse in coconut oil mice than in standard chow mice. Myocardial glucose uptake was 1.86-fold (p < 0.001 higher in coconut oil mice and was accompanied by higher myocardial pyruvate dehydrogenase levels and higher acetyl-CoA carboxylase levels. The coconut oil diet increased oxidative stress. Myocardial triglycerides and free fatty acids were lower (p < 0.05 in coconut oil mice. In conclusion, coconut oil aggravates pressure overload-induced cardiomyopathy.

  3. Aptamer conjugated paclitaxel and magnetic fluid loaded fluorescently tagged PLGA nanoparticles for targeted cancer therapy

    Energy Technology Data Exchange (ETDEWEB)

    Aravind, Athulya; Nair, Remya; Raveendran, Sreejith; Veeranarayanan, Srivani; Nagaoka, Yutaka; Fukuda, Takahiro; Hasumura, Takahashi; Morimoto, Hisao; Yoshida, Yasuhiko; Maekawa, Toru; Sakthi Kumar, D., E-mail: sakthi@toyo.jp

    2013-10-15

    Controlled and targeted drug delivery is an essential criterion in cancer therapy to reduce the side effects caused by non-specific drug release and toxicity. Targeted chemotherapy, sustained drug release and optical imaging have been achieved using a multifunctional nanocarrier constructed from poly (D, L-lactide-co-glycolide) nanoparticles (PLGA NPs), an anticancer drug paclitaxel (PTX), a fluorescent dye Nile red (NR), magnetic fluid (MF) and aptamers (Apt, AS1411, anti-nucleolin aptamer). The magnetic fluid and paclitaxel loaded fluorescently labeled PLGA NPs (MF-PTX-NR-PLGA NPs) were synthesized by a single-emulsion technique/solvent evaporation method using a chemical cross linker bis (sulfosuccinimidyl) suberate (BS3) to enable binding of aptamer on to the surface of the nanoparticles. Targeting aptamers were then introduced to the particles through the reaction with the cross linker to target the nucleolin receptors over expressed on the cancer cell surface. Specific binding and uptake of the aptamer conjugated magnetic fluid loaded fluorescently tagged PLGA NPs (Apt-MF-NR-PLGA NPs) to the target cancer cells induced by aptamers was observed using confocal microscopy. Cytotoxicity assay conducted in two cell lines (L929 and MCF-7) confirmed that targeted MCF-7 cancer cells were killed while control cells were unharmed. In addition, aptamer mediated delivery resulting in enhanced binding and uptake to the target cancer cells exhibited increased therapeutic effect of the drug. Moreover, these aptamer conjugated magnetic polymer vehicles apart from actively transporting drugs into specifically targeted tumor regions can also be used to induce hyperthermia or for facilitating magnetic guiding of particles to the tumor regions. - Highlights: • Aptamer escorted, theranostic biodegradable PLGA carriers were developed. • Can target cancer cells, control drug release, image and magnetically guide. • Highly specific to the targeted cancer cells thus delivering

  4. Glaucarubinone sensitizes KB cells to paclitaxel by inhibiting ABC transporters via ROS-dependent and p53-mediated activation of apoptotic signaling pathways.

    Science.gov (United States)

    Karthikeyan, Subburayan; Hoti, Sugeerappa Laxmanappa; Nazeer, Yasin; Hegde, Harsha Vasudev

    2016-07-05

    Multidrug resistance (MDR) is considered to be the major contributor to failure of chemotherapy in oral squamous cell carcinoma (SCC). This study was aimed to explore the effects and mechanisms of glaucarubinone (GLU), one of the major quassinoids from Simarouba glauca DC, in potentiating cytotoxicity of paclitaxel (PTX), an anticancer drug in KB cells. Our data showed that the administration of GLU pre-treatment significantly enhanced PTX anti-proliferative effect in ABCB1 over-expressing KB cells. The Rh 123 drug efflux studies revealed that there was a significant transport function inhibition by GLU-PTX treatment. Interestingly, it was also found that this enhanced anticancer efficacy of GLU was associated with PTX-induced cell arrest in the G2/M phase of cell cycle. Further, the combined treatment of GLU-PTX had significant decrease in the expression levels of P-gp, MRPs, and BCRP in resistant KB cells at both mRNA and protein levels. Furthermore, the combination treatments showed significant reactive oxygen species (ROS) production, chromatin condensation and reduced mitochondrial membrane potential in resistant KB cells. The results from DNA fragmentation analysis also demonstrated the GLU induced apoptosis in KB cells and its synergy with PTX. Importantly, GLU and/or PTX triggered apoptosis through the activation of pro-apoptotic proteins such as p53, Bax, and caspase-9. Our findings demonstrated for the first time that GLU causes cell death in human oral cancer cells via the ROS-dependent suppression of MDR transporters and p53-mediated activation of the intrinsic mitochondrial pathway of apoptosis. Additionally, the present study also focussed on investigation of the protective effect of GLU and combination drugs in human normal blood lymphocytes. Normal blood lymphocytes assay indicated that GLU is able to induce selective toxicity in cancer cells and in silico molecular docking studies support the choice of GLU as ABC inhibitor to enhance PTX efficacy

  5. Infection dynamics of vancomycin and inducible clindamycin resistant Enterococcus faecalis in an Indian teaching hospital

    Directory of Open Access Journals (Sweden)

    Debasmita Dubey

    2015-06-01

    Full Text Available Objective: To do surveillance for vancomycin and inducible clindamycin resistance of Enterococcus faecalis (E. faecalis, a Gram-positive bacterium in a teaching hospital. Methods: E. faecalis strains isolated from clinical samples were screened for vancomycin and inducible clindamycin resistance, i.e., D-test positivity, using vancomycin screen agar and blood agar plates, respectively. For the D-test screening, erythromycin resistant (Er-r and clindamycin sensitive (Cd-s strain were used. Results: Of 265 isolated E. faecalis strains, 159 (60% were vancomycin resistant Enterococcus (VRE and 106 were vancomycin sensitive Enterococcus (VSE. Of 265 strains, 42 were constitutively resistant to clindamycin and erythromycin and of 148 Er-r and Cd-s strains, 87 (32.83% had D-test positivity, while the rest 61 strains were D-test negatives. D-test results examined with 6 hospital factors as bivalents, only 2 factors, the VSE/VRE and the presence/absence of prior antibiotic use > 90 days bivalent were statistically significant. A VRE strain with D-test positivity would be picked up 0.570 2 times more frequently than a strain with VSE and D-test positivity. Also, patients with prior antibiotic use > 90 days had 3.737 5 times more chance of picking up D-test positive strains than patients without any prior antibiotic use. Resistance pattern of E. faecalis strains to individual 14 antibiotics were recorded; the maximum values of resistance were against ampicillin 10 μg/disc and linezolid 30 μg/disc. Student’s t-test for hospital acquired and community acquired data revealed that drug resistant strains were equally prevalent in both sources. Conclusions: Prevalence of 60% VRE in both hospital and adjoining community creates consternation. In total 87 (32.83% strains had D-test positivity; patients who had used antibiotics within the last 90 days have got an ample chance of picking of D-test positive E. faecalis. D-test protocol should be followed with

  6. Deciphering the hormonal signalling network behind the systemic resistance induced by Trichoderma harzianum in tomato

    Science.gov (United States)

    Martínez-Medina, Ainhoa; Fernández, Iván; Sánchez-Guzmán, María J.; Jung, Sabine C.; Pascual, Jose A.; Pozo, María J.

    2013-01-01

    Root colonization by selected Trichoderma isolates can activate in the plant a systemic defense response that is effective against a broad-spectrum of plant pathogens. Diverse plant hormones play pivotal roles in the regulation of the defense signaling network that leads to the induction of systemic resistance triggered by beneficial organisms [induced systemic resistance (ISR)]. Among them, jasmonic acid (JA) and ethylene (ET) signaling pathways are generally essential for ISR. However, Trichoderma ISR (TISR) is believed to involve a wider variety of signaling routes, interconnected in a complex network of cross-communicating hormone pathways. Using tomato as a model, an integrative analysis of the main mechanisms involved in the systemic resistance induced by Trichoderma harzianum against the necrotrophic leaf pathogen Botrytis cinerea was performed. Root colonization by T. harzianum rendered the leaves more resistant to B. cinerea independently of major effects on plant nutrition. The analysis of disease development in shoots of tomato mutant lines impaired in the synthesis of the key defense-related hormones JA, ET, salicylic acid (SA), and abscisic acid (ABA), and the peptide prosystemin (PS) evidenced the requirement of intact JA, SA, and ABA signaling pathways for a functional TISR. Expression analysis of several hormone-related marker genes point to the role of priming for enhanced JA-dependent defense responses upon pathogen infection. Together, our results indicate that although TISR induced in tomato against necrotrophs is mainly based on boosted JA-dependent responses, the pathways regulated by the plant hormones SA- and ABA are also required for successful TISR development. PMID:23805146

  7. Effect of vitamin D on stress-induced hyperglycaemia and insulin resistance in critically ill patients.

    Science.gov (United States)

    Alizadeh, N; Khalili, H; Mohammadi, M; Abdollahi, A; Ala, S

    2016-05-01

    Effects of vitamin D supplementation on the glycaemic indices and insulin resistance in diabetic and non-diabetic patients were studied. In this study, effects of vitamin D supplementation on stress-induced hyperglycaemia and insulin resistance were evaluated in non-diabetic surgical critically ill patients. Adult surgical patients with stress-induced hyperglycaemia within the first 24 h of admission to the ICU were recruited. The patients randomly assigned to receive either vitamin D or placebo. Patients in the vitamin D group received a single dose of 600,000 IU vitamin D3 as intramuscular injection at time of recruitment. Besides demographic and clinical characteristics of the patients, plasma glucose, insulin, 25(OH) D and adiponectin levels were measured at the time of ICU admission and day 7. Homoeostasis model assessment for insulin resistance (HOMA-IR) and homestasis model assessment adiponectin (HOMA-AD) ratio were considered at the times of assessment. Comparing with the baseline, plasma 25(OH) D level significantly increased in the subjects who received vitamin D (p = 0.04). Improvement in fasting plasma glucose levels was detected in day 7 of the study compared with the baseline status in both groups. HOMA-IR showed a decrement pattern in vitamin D group (p = 0.09). Fasting plasma adiponectin levels increased significantly in the vitamin D group (p = 0.007), but not in the placebo group (p = 0.38). Finally, changes in HOMA-AD ratio were not significant in the both groups. Vitamin D supplementation showed positive effect on plasma adiponectin level, as a biomarker of insulin sensitivity in surgical critically ill patients with stress-induced hyperglycaemia. However, effects of vitamin D supplementation on HOMA-IR and HOMA-AD as indicators of insulin resistance were not significant. © 2016 John Wiley & Sons Ltd.

  8. [Molecular mechanism for ET-1-induced insulin resistance in skeletal muscle cells].

    Science.gov (United States)

    Horinouchi, Takahiro; Mazaki, Yuichi; Terada, Koji; Miwa, Soichi

    2018-01-01

    Insulin resistance is a condition where the sensitivity to insulin of the tissues expressing insulin receptor (InsR) is decreased due to a functional disturbance of InsR-mediated intracellular signaling. Insulin promotes the entry of glucose into the tissues and skeletal muscle is the most important tissue responsible for the insulin's action of decreasing blood glucose levels. Endothelin-1 (ET-1), a potent vasoconstrictor and pro-inflammatory peptide, induces insulin resistance through a direct action on skeletal muscle. However, the signaling pathways of ET-1-induced insulin resistance in skeletal muscle remain unclear. Here we show molecular mechanism underlying the inhibitory effect of ET-1 on insulin-stimulated Akt phosphorylation and glucose uptake in myotubes of rat L6 skeletal muscle cell line. mRNA expression levels of differentiation marker genes, MyoD and myogenin, were increased during L6 myoblasts differentiation into myotubes. Some of myotubes possessed the ability to spontaneously contract. In myotubes, insulin promoted Akt phosphorylation at Thr 308 and Ser 473 , and [ 3 H]-labelled 2-deoxy-D-glucose ([ 3 H]2-DG) uptake. The insulin-facilitated Akt phosphorylation and [ 3 H]2-DG uptake were inhibited by ET-1. The inhibitory effect of ET-1 was counteracted by blockade of ET type A receptor (ET A R), inhibition of G q/11 protein, and siRNA knockdown of G protein-coupled receptor kinase 2 (GRK2). The exogenously overexpressed GRK2 directly bound to endogenous Akt and their association was facilitated by ET-1. In summary, activation of ET A R with ET-1 inhibits insulin-induced Akt phosphorylation and [ 3 H]2-DG uptake in a G q/11 protein- and GRK2-dependent manner in skeletal muscle. These findings indicate that ET A R and GRK2 are potential targets for insulin resistance.

  9. Inhibition of Notch1 increases paclitaxel sensitivity to human breast cancer

    Institute of Scientific and Technical Information of China (English)

    Zhao Li; Ma Yongjie; Gu Feng; Fu Li

    2014-01-01

    Background Paclitaxel (PAC) is the first-line chemotherapy drug for most breast cancer patients,but clinical studies showed that some breast cancer patients were insensitive to PAC,which led to chemotherapy failure.It was reported that Notch1 signaling participated in drug resistance of breast cancer.Here,we show whether Notch1 expression is related to PAC sensitivity of breast cancer.Methods We employed Notch1 siRNA and Notch1 inhibitor,N-[N-(3,5-difluorophenacetyl)-1-alanyl]-S-phenylglycine t-butylester (DAPT),to down regulate Notch1 expression in human breast cancer cells MDA-MB-231,and detected the inhibition effect by Western blotting and reverse trans cription-polymerase chain reaction,respectively.After 24 hours exposure to different concentration of PAC (0,1,5,10,15,20,and 25 μg/ml),the viability of the control group and experimental group cells was tested by MTT.We also examined the expression of Notch1 in PAC sensitive and nonsensitive breast cancer patients,respectively by immunohistochemistry (IHC).The PAC sensitivity of breast cancer patients were identified by collagen gel droplet embedded culture-drug sensitivity test (CD-DST).Results Down regulation of Notch1 expression by Notch1siRNA interference or Notch1 inhibitor increased the PAC sensitivity in MDA-MB-231 cells (P <0.05).Also,the expression of Notch1 in PAC sensitive patients was much lower than that of PAC non-sensitive patients (P <0.01).Conclusion Notch1 expression has an effect on PAC sensitivity in breast cancer patients,and the inhibition of Notch1 increases paclitaxel sensitivity to human breast cancer.

  10. High sugar-induced insulin resistance in Drosophila relies on the lipocalin Neural Lazarillo.

    Directory of Open Access Journals (Sweden)

    Matthieu Y Pasco

    Full Text Available In multicellular organisms, insulin/IGF signaling (IIS plays a central role in matching energy needs with uptake and storage, participating in functions as diverse as metabolic homeostasis, growth, reproduction and ageing. In mammals, this pleiotropy of action relies in part on a dichotomy of action of insulin, IGF-I and their respective membrane-bound receptors. In organisms with simpler IIS, this functional separation is questionable. In Drosophila IIS consists of several insulin-like peptides called Dilps, activating a unique membrane receptor and its downstream signaling cascade. During larval development, IIS is involved in metabolic homeostasis and growth. We have used feeding conditions (high sugar diet, HSD that induce an important change in metabolic homeostasis to monitor possible effects on growth. Unexpectedly we observed that HSD-fed animals exhibited severe growth inhibition as a consequence of peripheral Dilp resistance. Dilp-resistant animals present several metabolic disorders similar to those observed in type II diabetes (T2D patients. By exploring the molecular mechanisms involved in Drosophila Dilp resistance, we found a major role for the lipocalin Neural Lazarillo (NLaz, a target of JNK signaling. NLaz expression is strongly increased upon HSD and animals heterozygous for an NLaz null mutation are fully protected from HSD-induced Dilp resistance. NLaz is a secreted protein homologous to the Retinol-Binding Protein 4 involved in the onset of T2D in human and mice. These results indicate that insulin resistance shares common molecular mechanisms in flies and human and that Drosophila could emerge as a powerful genetic system to study some aspects of this complex syndrome.

  11. IL6 induces TAM resistance via kinase-specific phosphorylation of ERα in OVCA cells.

    Science.gov (United States)

    Wang, Yue; Niu, Xiu Long; Guo, Xiao Qin; Yang, Jing; Li, Ling; Qu, Ye; Xiu Hu, Cun; Mao, Li Qun; Wang, Dan

    2015-06-01

    About 40-60% of ovarian cancer (OVCA) cases express ERα, but only a small proportion of patients respond clinically to anti-estrogen treatment with estrogen receptor (ER) antagonist tamoxifen (TAM). The mechanism of TAM resistance in the course of OVCA progression remains unclear. However, IL6 plays a critical role in the development and progression of OVCA. Our recent results indicated that IL6 secreted by OVCA cells may promote the resistance of these cells to TAM via ER isoforms and steroid hormone receptor coactivator-1. Here we demonstrate that both exogenous (a relatively short period of treatment with recombinant IL6) and endogenous IL6 (generated as a result of transfection with a plasmid encoding sense IL6) increases expression of pERα-Ser118 and pERα-Ser167 in non-IL6-expressing A2780 cells, while deleting endogenous IL6 expression in IL6-overexpressing CAOV-3 cells (by transfection with a plasmid encoding antisense IL6) reduces expression of pERα-Ser118 and pERα-Ser167, indicating that IL6-induced TAM resistance may also be associated with increased expression of pERα-Ser118 and pERα-Ser167 in OVCA cells. Results of further investigation indicate that IL6 phosphorylates ERα at Ser118 and Ser167 by triggering activation of MEK/ERK and phosphotidylinositol 3 kinase/Akt signaling, respectively, to activate the ER pathway and thereby induce OVCA cells resistance to TAM. These results indicate that IL6 secreted by OVCA cells may also contribute to the refractoriness of these cells to TAM via the crosstalk between ER and IL6-mediated intracellular signal transduction cascades. Overexpression of IL6 not only plays an important role in OVCA progression but also promotes TAM resistance. Our results indicate that TAM-IL6-targeted adjunctive therapy may lead to a more effective intervention than TAM alone. © 2015 Society for Endocrinology.

  12. A pilot study of minocycline for the prevention of paclitaxel-associated neuropathy: ACCRU study RU221408I.

    Science.gov (United States)

    Pachman, Deirdre R; Dockter, Travis; Zekan, Patricia J; Fruth, Briant; Ruddy, Kathryn J; Ta, Lauren E; Lafky, Jacqueline M; Dentchev, Todor; Le-Lindqwister, Nguyet Anh; Sikov, William M; Staff, Nathan; Beutler, Andreas S; Loprinzi, Charles L

    2017-11-01

    Paclitaxel is associated with both an acute pain syndrome (P-APS) and chronic chemotherapy-induced peripheral neuropathy (CIPN). Given that extensive animal data suggest that minocycline may prevent chemotherapy-induced neurotoxicity, the purpose of this pilot study was to investigate the efficacy of minocycline for the prevention of CIPN and the P-APS. Patients with breast cancer were enrolled prior to initiating neoadjuvant or adjuvant weekly paclitaxel for 12 weeks and were randomized to receive minocycline 200 mg on day 1 followed by 100 mg twice daily or a matching placebo. Patients completed (1) an acute pain syndrome questionnaire daily during chemotherapy to measure P-APS and (2) the EORTC QLQ-CIPN20 questionnaire at baseline, prior to each dose of paclitaxel, and monthly for 6 months post treatment, to measure CIPN. Forty-seven patients were randomized. There were no remarkable differences noted between the minocycline and placebo groups for the overall sensory neuropathy score of the EORTC QLQ-CIPN20 or its individual components, which evaluate tingling, numbness and shooting/burning pain in hands and feet. However, patients taking minocycline had a significant reduction in the daily average pain score attributed to P-APS (p = 0.02). Not only were no increased toxicities reported with minocycline, but there was a significant reduction in fatigue (p = 0.02). Results of this pilot study do not support the use of minocycline to prevent CIPN, but suggest that it may reduce P-APS and decrease fatigue; further study of the impact of this agent on those endpoints may be warranted.

  13. First line treatment of advanced non-small-cell lung cancer – specific focus on albumin bound paclitaxel

    Directory of Open Access Journals (Sweden)

    Gupta N

    2013-12-01

    Full Text Available Neha Gupta, Hassan Hatoum, Grace K DyDepartment of Medicine, Roswell Park Cancer Institute, Buffalo, NY, USAAbstract: Lung cancer is the leading cause of cancer mortality worldwide in both men and women. Non-small-cell lung cancer (NSCLC is the most common type of lung cancer, accounting for more than 80% of cases. Paclitaxel has a broad spectrum of activity against various malignancies, including NSCLC. Paclitaxel is poorly soluble in water and thus, until recently, its commercially available preparations contained a non-ionic solvent Cremophor EL®. Cremophor EL® improves the solubility of paclitaxel and allows its intravenous administration. However, certain side-effects associated with paclitaxel, such as hypersensitivity reactions, myelosuppression, and peripheral neuropathy, are known to be worsened by Cremophor®. Nanoparticle albumin-bound paclitaxel ([nab-paclitaxel] ABRAXANE® ABI-007 is a new generation formulation of paclitaxel that obviates the need for Cremophor®, resulting in a safer and faster infusion without requiring the use of premedications to avoid hypersensitivity. Albumin-binding receptor-mediated delivery and lack of sequestering Cremophor® micelles allow higher intratumoral concentration of pharmacologically active paclitaxel. Multiple clinical trials have demonstrated a superior tolerability profile of nab-paclitaxel in comparison to solvent-bound paclitaxel (sb-paclitaxel. A recent Phase III trial compared the effects of weekly nab-paclitaxel in combination with carboplatin versus sb-paclitaxel in combination with carboplatin given every 3 weeks for first line treatment of NSCLC. This trial highlights the weekly nab-paclitaxel combination as an alternate treatment option for NSCLC, with higher response rate in squamous cell NSCLC and longer survival in elderly patients. This review will focus on the properties of nab-paclitaxel and its use in the first line treatment of NSCLC.Keywords: ABI-007, Abraxane, nab-paclitaxel

  14. The co-solvent Cremophor EL limits absorption of orally administered paclitaxel in cancer patients.

    Science.gov (United States)

    Malingré, M M; Schellens, J H; Van Tellingen, O; Ouwehand, M; Bardelmeijer, H A; Rosing, H; Koopman, F J; Schot, M E; Ten Bokkel Huinink, W W; Beijnen, J H

    2001-11-16

    The purpose of this study was to investigate the effect of the co-solvents Cremophor EL and polysorbate 80 on the absorption of orally administered paclitaxel. 6 patients received in a randomized setting, one week apart oral paclitaxel 60 mg m(-2) dissolved in polysorbate 80 or Cremophor EL. For 3 patients the amount of Cremophor EL was 5 ml m(-2), for the other three 15 ml m(-2). Prior to paclitaxel administration patients received 15 mg kg(-1) oral cyclosporin A to enhance the oral absorption of the drug. Paclitaxel formulated in polysorbate 80 resulted in a significant increase in the maximal concentration (C(max)) and area under the concentration-time curve (AUC) of paclitaxel in comparison with the Cremophor EL formulations (P = 0.046 for both parameters). When formulated in Cremophor EL 15 ml m(-2), paclitaxel C(max) and AUC values were 0.10 +/- 0.06 microM and 1.29 +/- 0.99 microM h(-1), respectively, whereas these values were 0.31 +/- 0.06 microM and 2.61 +/- 1.54 microM h(-1), respectively, when formulated in polysorbate 80. Faecal data revealed a decrease in excretion of unchanged paclitaxel for the polysorbate 80 formulation compared to the Cremophor EL formulations. The amount of paclitaxel excreted in faeces was significantly correlated with the amount of Cremophor EL excreted in faeces (P = 0.019). When formulated in Cremophor EL 15 ml m(-2), paclitaxel excretion in faeces was 38.8 +/- 13.0% of the administered dose, whereas this value was 18.3 +/-15.5% for the polysorbate 80 formulation. The results show that the co-solvent Cremophor EL is an important factor limiting the absorption of orally administered paclitaxel from the intestinal lumen. They highlight the need for designing a better drug formulation in order to increase the usefulness of the oral route of paclitaxel

  15. Susceptibility to radiation-induced mammary carcinoma in genetically resistant Copenhagen rats

    International Nuclear Information System (INIS)

    Kamiya, Kenji; Nitta, Yumiko; Gould, M.N.

    2000-01-01

    The objective of this experiment was to compare the cellular basis of mammary cancer induction by a chemical carcinogen with induction by ionizing radiation in three strains of rats (inbred that have different genetic susceptibilities: COP rats, F344 rats, and WF rats). Rats were given a single intraperitoneal injection of 50 mg MNU/kg body weight as a mammary-tumor-inducing chemical carcinogen and were irradiated with a 3.0 Gy dose of 60 Co gamma rays at a dose rate of 26.58±1.19 cGy/min. The rats were inspected weekly, and they were killed and necropsied whenever palpable tumors were detected or they became moribund. The histopathological and immunohistochemical characteristics of the mammary tumors were investigated. A transplantation experiment using selected primary mammary tumors that developed in COP rats exposed to gamma rays was also performed to investigate the transplantability of mammary tumors induced by ionizing radiation. The sensitivity of the WF and F344 rats and the resistance of the COP rats to mammary carcinoma induction by the chemical carcinogen MNU was confirmed. In contrast to the chemical carcinogens, no difference in susceptibility to radiation induction of mammary carcinomas was detected among the three strains of rats, and immunohistochemical examination indicated that the radiation-induced carcinomas consisted of more highly differentiated cells than the MNU-induced cancers. The results of the experiment appear to support the hypothesis that differentiated mammary gland tissue is more resistant to chemical carcinogens than to cancer induction by radiation. The authors conclude that radiation-induced cancers in rats may develop via different pathways or from different cell populations than chemically induced cancers. (K.H.)

  16. Susceptibility to radiation-induced mammary carcinoma in genetically resistant Copenhagen rats

    Energy Technology Data Exchange (ETDEWEB)

    Kamiya, Kenji; Nitta, Yumiko [Hiroshima Univ. (Japan). Research Inst. for Radiation Biology and Medicine; Gould, M.N.

    2000-07-01

    The objective of this experiment was to compare the cellular basis of mammary cancer induction by a chemical carcinogen with induction by ionizing radiation in three strains of rats (inbred that have different genetic susceptibilities: COP rats, F344 rats, and WF rats). Rats were given a single intraperitoneal injection of 50 mg MNU/kg body weight as a mammary-tumor-inducing chemical carcinogen and were irradiated with a 3.0 Gy dose of {sup 60} Co gamma rays at a dose rate of 26.58{+-}1.19 cGy/min. The rats were inspected weekly, and they were killed and necropsied whenever palpable tumors were detected or they became moribund. The histopathological and immunohistochemical characteristics of the mammary tumors were investigated. A transplantation experiment using selected primary mammary tumors that developed in COP rats exposed to gamma rays was also performed to investigate the transplantability of mammary tumors induced by ionizing radiation. The sensitivity of the WF and F344 rats and the resistance of the COP rats to mammary carcinoma induction by the chemical carcinogen MNU was confirmed. In contrast to the chemical carcinogens, no difference in susceptibility to radiation induction of mammary carcinomas was detected among the three strains of rats, and immunohistochemical examination indicated that the radiation-induced carcinomas consisted of more highly differentiated cells than the MNU-induced cancers. The results of the experiment appear to support the hypothesis that differentiated mammary gland tissue is more resistant to chemical carcinogens than to cancer induction by radiation. The authors conclude that radiation-induced cancers in rats may develop via different pathways or from different cell populations than chemically induced cancers. (K.H.)

  17. Development of resistance to serotonin-induced itch in bile duct ligated mice.

    Science.gov (United States)

    Ostadhadi, Sattar; Haddadi, Nazgol-Sadat; Foroutan, Arash; Azimi, Ehsan; Elmariah, Sarina; Dehpour, Ahmad-Reza

    2017-06-01

    Cholestatic itch can be severe and significantly impair the quality of life of patients. The serotonin system is implicated in cholestatic itch; however, the pruritogenic properties of serotonin have not been evaluated in cholestatic mice. Here, we investigated the serotonin-induced itch in cholestatic mice which was induced by bile duct ligation (BDL). Serotonin, sertraline or saline were administered intradermally to the rostral back area in BDL and sham operated (SHAM) mice, and the scratching behaviour was videotaped for 1 hour. Bile duct ligated mice had significantly increased scratching responses to saline injection on the seventh day after surgery. Additionally, serotonin or sertraline significantly induced scratching behaviour in BDL mice compared to saline at day 7 after surgery, while it did not induce itch at day 5. The scratching behaviour induced by serotonin or sertraline was significantly less in BDL mice compared to SHAM mice. Likewise, the locomotor activity of BDL or SHAM mice was not significantly different from unoperated (UNOP) mice on the fifth and seventh day, suggesting that the scratching behaviour was not affected by motor dysfunctions. Our data suggest that despite the potentiation of evoked itch, a resistance to serotonin-induced itch is developed in cholestatic mice. © 2017 John Wiley & Sons Australia, Ltd.

  18. Mapping geological structures in bedrock via large-scale direct current resistivity and time-domain induced polarization tomography

    DEFF Research Database (Denmark)

    Rossi, Matteo; Olsson, Per-Ivar; Johansson, Sara

    2017-01-01

    -current resistivity distribution of the subsoil and the phase of the complex conductivity using a constant-phase angle model. The joint interpretation of electrical resistivity and induced-polarization models leads to a better understanding of complex three-dimensional subsoil geometries. The results have been......An investigation of geological conditions is always a key point for planning infrastructure constructions. Bedrock surface and rock quality must be estimated carefully in the designing process of infrastructures. A large direct-current resistivity and time-domain induced-polarization survey has......, there are northwest-trending Permian dolerite dykes that are less deformed. Four 2D direct-current resistivity and time-domain induced-polarization profiles of about 1-km length have been carefully pre-processed to retrieve time-domain induced polarization responses and inverted to obtain the direct...

  19. The necrotic signal induced by mycophenolic acid overcomes apoptosis-resistance in tumor cells.

    Directory of Open Access Journals (Sweden)

    Gwendaline Guidicelli

    Full Text Available BACKGROUND: The amount of inosine monophosphate dehydrogenase (IMPDH, a pivotal enzyme for the biosynthesis of the guanosine tri-phosphate (GTP, is frequently increased in tumor cells. The anti-viral agent ribavirin and the immunosuppressant mycophenolic acid (MPA are potent inhibitors of IMPDH. We recently showed that IMPDH inhibition led to a necrotic signal requiring the activation of Cdc42. METHODOLOGY/PRINCIPAL FINDINGS: Herein, we strengthened the essential role played by this small GTPase in the necrotic signal by silencing Cdc42 and by the ectopic expression of a constitutive active mutant of Cdc42. Since resistance to apoptosis is an essential step for the tumorigenesis process, we next examined the effect of the MPA-mediated necrotic signal on different tumor cells demonstrating various mechanisms of resistance to apoptosis (Bcl2-, HSP70-, Lyn-, BCR-ABL-overexpressing cells. All tested cells remained sensitive to MPA-mediated necrotic signal. Furthermore, inhibition of IMPDH activity in Chronic Lymphocytic Leukemia cells was significantly more efficient at eliminating malignant cells than apoptotic inducers. CONCLUSIONS/SIGNIFICANCE: These findings indicate that necrosis and apoptosis are split signals that share few if any common hub of signaling. In addition, the necrotic signaling pathway induced by depletion of the cellular amount of GTP/GDP would be of great interest to eliminate apoptotic-resistant tumor cells.

  20. Tribbles 3 Mediates Endoplasmic Reticulum Stress-Induced Insulin Resistance in Skeletal Muscle

    Science.gov (United States)

    Koh, Ho-Jin; Toyoda, Taro; Didesch, Michelle M.; Lee, Min-Young; Sleeman, Mark W.; Kulkarni, Rohit N.; Musi, Nicolas; Hirshman, Michael F.; Goodyear, Laurie J.

    2013-01-01

    Endoplasmic Reticulum (ER) stress has been linked to insulin resistance in multiple tissues but the role of ER stress in skeletal muscle has not been explored. ER stress has also been reported to increase tribbles 3 (TRB3) expression in multiple cell lines. Here, we report that high fat feeding in mice, and obesity and type 2 diabetes in humans significantly increases TRB3 and ER stress markers in skeletal muscle. Overexpression of TRB3 in C2C12 myotubes and mouse tibialis anterior muscles significantly impairs insulin signaling. Incubation of C2C12 cells and mouse skeletal muscle with ER stressors thapsigargin and tunicamycin increases TRB3 and impairs insulin signaling and glucose uptake, effects reversed in cells overexpressing RNAi for TRB3 and in muscles from TRB3 knockout mice. Furthermore, TRB3 knockout mice are protected from high fat diet-induced insulin resistance in skeletal muscle. These data demonstrate that TRB3 mediates ER stress-induced insulin resistance in skeletal muscle. PMID:23695665

  1. Arginine- and Polyamine-Induced Lactic Acid Resistance in Neisseria gonorrhoeae.

    Directory of Open Access Journals (Sweden)

    Zheng Gong

    Full Text Available Microbe-derived lactic acid protects women from pathogens in their genital tract. The purpose of this study was to determine lactic acid susceptibility of Neisseria gonorrhoeae, and identify potential acid resistance mechanisms present in this pathogen. Tested in vitro, lactic acid killed all 10 gonococcal strains analyzed in a low pH-dependent manner. Full inactivation occurred at pH 4.5. At low pH, lactic acid treatment resulted in the entry of the DNA-binding fluorochrome propidium iodide into the microbial cells, suggesting that hydrogen ions from lactic acid compromise the integrity of the bacterial cell wall/membrane. Most likely, hydrogen ions also inactivate intracellular proteins since arginine rendered significant protection against lactic acid presumably through action of the gonococcal arginine decarboxylase, an enzyme located in the bacterial cytoplasm. Surprisingly, arginine also lessened lactic acid-mediated cell wall/membrane disruption. This effect is probably mediated by agmatine, a triamine product of arginine decarboxylase, since agmatine demonstrated a stronger protective effect on GC than arginine at equal molar concentration. In addition to agmatine, diamines cadaverine and putrescine, which are generated by bacterial vaginosis-associated microbes, also induced significant resistance to lactic acid-mediated GC killing and cell wall/membrane disruption. These findings suggest that the arginine-rich semen protects gonococci through both neutralization-dependent and independent mechanisms, whereas polyamine-induced acid resistance contributes to the increased risk of gonorrhea in women with bacterial vaginosis.

  2. Isolation of Mycorrhizal Rhizoctonia as resistance inducer of Dendrobium macrophyllum to drought

    Science.gov (United States)

    Soelistijono, R.; Daryanti; Handayani, M. T.

    2018-03-01

    One of the obstacles encountered in the cultivation of orchids Dendrobium macrophyllum is difficult to cultivate in areas with high drought due to the slow absorption of nutrients. Based on previous research, the mycorrhizal binucleate Rhizoctonia (BNR) has the ability to increase the resistance of vanilla (Vanilla planifolia Andrews) to drought, but it has never been tried on orchid Dendrobium macrophyllum. The objectives of this study was to isolate resistance inducer organisms by induced resistance techniques on orchids against drought. It is expected that the administration of mycorrhizal Rhizoctonia can increase the absorption of nutrients in D. macrophyllum which is exposed to high water stress. Each treatment consisted of 3 replications of 3 potted plants. The characterization of mycorrhizal Rhizoctonia isolate from D. macrophyllum root from Surakarta, Kopeng, Magelang, and Yogyakarta did not different morphologically. Character equations are in colony color, cell length and number of cores, while character differences are present in cell width and all isolates are capable of forming a peloton structure.

  3. Transit through the flea vector induces a pretransmission innate immunity resistance phenotype in Yersinia pestis.

    Directory of Open Access Journals (Sweden)

    Viveka Vadyvaloo

    2010-02-01

    Full Text Available Yersinia pestis, the agent of plague, is transmitted to mammals by infected fleas. Y. pestis exhibits a distinct life stage in the flea, where it grows in the form of a cohesive biofilm that promotes transmission. After transmission, the temperature shift to 37 degrees C induces many known virulence factors of Y. pestis that confer resistance to innate immunity. These factors are not produced in the low-temperature environment of the flea, however, suggesting that Y. pestis is vulnerable to the initial encounter with innate immune cells at the flea bite site. In this study, we used whole-genome microarrays to compare the Y. pestis in vivo transcriptome in infective fleas to in vitro transcriptomes in temperature-matched biofilm and planktonic cultures, and to the previously characterized in vivo gene expression profile in the rat bubo. In addition to genes involved in metabolic adaptation to the flea gut and biofilm formation, several genes with known or predicted roles in resistance to innate immunity and pathogenicity in the mammal were upregulated in the flea. Y. pestis from infected fleas were more resistant to phagocytosis by macrophages than in vitro-grown bacteria, in part attributable to a cluster of insecticidal-like toxin genes that were highly expressed only in the flea. Our results suggest that transit through the flea vector induces a phenotype that enhances survival and dissemination of Y. pestis after transmission to the mammalian host.

  4. Riboflavin-Induced Disease Resistance Requires the Mitogen-Activated Protein Kinases 3 and 6 in Arabidopsis thaliana.

    Science.gov (United States)

    Nie, Shengjun; Xu, Huilian

    2016-01-01

    As a resistance elicitor, riboflavin (vitamin B2) protects plants against a wide range of pathogens. At molecular biological levels, it is important to elucidate the signaling pathways underlying the disease resistance induced by riboflavin. Here, riboflavin was tested to induce resistance against virulent Pseudomonas syringae pv. Tomato DC3000 (Pst DC3000) in Arabidopsis. Results showed that riboflavin induced disease resistance based on MAPK-dependent priming for the expression of PR1 gene. Riboflavin induced transient expression of PR1 gene. However, following Pst DC3000 inoculation, riboflavin potentiated stronger PR1 gene transcription. Further was suggested that the transcript levels of mitogen-activated protein kinases, MPK3 and MPK6, were primed under riboflavin. Upon infection by Pst DC3000, these two enzymes were more strongly activated. The elevated activation of both MPK3 and MPK6 was responsible for enhanced defense gene expression and resistance after riboflavin treatment. Moreover, riboflavin significantly reduced the transcript levels of MPK3 and MPK6 by application of AsA and BAPTA, an H2O2 scavenger and a calcium (Ca2+) scavenger, respectively. In conclusion, MPK3 and MPK6 were responsible for riboflavin-induced resistance, and played an important role in H2O2- and Ca2+-related signaling pathways, and this study could provide a new insight into the mechanistic study of riboflavin-induced defense responses.

  5. Resistive Switching and Voltage Induced Modulation of Tunneling Magnetoresistance in Nanosized Perpendicular Organic Spin Valves

    Science.gov (United States)

    Schmidt, Georg; Goeckeritz, Robert; Homonnay, Nico; Mueller, Alexander; Fuhrmann, Bodo

    Resistive switching has already been reported in organic spin valves (OSV), however, its origin is still unclear. We have fabricated nanosized OSV based on La0.7Sr0.3MnO3/Alq3/Co. These devices show fully reversible resistive switching of up to five orders of magnitude. The magnetoresistance (MR) is modulated during the switching process from negative (-70%) to positive values (+23%). The results are reminiscent of experiments claiming magnetoelectric coupling in LSMO based tunneling structures using ferroelectric barriers. By analyzing the I/V characteristics of the devices we can show that transport is dominated by tunneling through pinholes. The resistive switching is caused by voltage induced creation and motion of oxygen vacancies at the LSMO surface, however, the resulting tunnel barrier is complemented by a second adjacent barrier in the organic semiconductor. Our model shows that the barrier in the organic material is constant, causing the initial MR while the barrier in the LMSO can be modulated by the voltage resulting in the resistive switching and the modulation of the MR as the coupling to the states in the LSMO changes. A switching caused by LSMO only is also supported by the fact that replacing ALQ3 by H2PC yields almost identical results. Supported by the DFG in the SFB762.

  6. Pharmacological TLR4 Inhibition Protects against Acute and Chronic Fat-Induced Insulin Resistance in Rats.

    Science.gov (United States)

    Zhang, Ning; Liang, Hanyu; Farese, Robert V; Li, Ji; Musi, Nicolas; Hussey, Sophie E

    2015-01-01

    To evaluate whether pharmacological TLR4 inhibition protects against acute and chronic fat-induced insulin resistance in rats. For the acute experiment, rats received a TLR4 inhibitor [TAK-242 or E5564 (2x5 mg/kg i.v. bolus)] or vehicle, and an 8-h Intralipid (20%, 8.5 mg/kg/min) or saline infusion, followed by a two-step hyperinsulinemic-euglycemic clamp. For the chronic experiment, rats were subcutaneously implanted with a slow-release pellet of TAK-242 (1.5 mg/d) or placebo. Rats then received a high fat diet (HFD) or a low fat control diet (LFD) for 10 weeks, followed by a two-step insulin clamp. Acute experiment; the lipid-induced reduction (18%) in insulin-stimulated glucose disposal (Rd) was attenuated by TAK-242 and E5564 (the effect of E5564 was more robust), suggesting improved peripheral insulin action. Insulin was able to suppress hepatic glucose production (HGP) in saline- but not lipid-treated rats. TAK-242, but not E5564, partially restored this effect, suggesting improved HGP. Chronic experiment; insulin-stimulated Rd was reduced ~30% by the HFD, but completely restored by TAK-242. Insulin could not suppress HGP in rats fed a HFD and TAK-242 had no effect on HGP. Pharmacological TLR4 inhibition provides partial protection against acute and chronic fat-induced insulin resistance in vivo.

  7. Loss of Smad4 in colorectal cancer induces resistance to 5-fluorouracil through activating Akt pathway.

    Science.gov (United States)

    Zhang, B; Zhang, B; Chen, X; Bae, S; Singh, K; Washington, M K; Datta, P K

    2014-02-18

    Higher frequency of Smad4 inactivation or loss of expression is observed in metastasis of colorectal cancer (CRC) leading to unfavourable survival and contributes to chemoresistance. However, the molecular mechanism of how Smad4 regulates chemosensitivity of CRC is unknown. We evaluated how the loss of Smad4 in CRC enhanced chemoresistance to 5-fluorouracil (5-FU) using two CRC cell lines in vitro and in vivo. Immunoblotting with cell and tumour lysates and immunohistochemical analyses with tissue microarray were performed. Knockdown or loss of Smad4 induced tumorigenicity, migration, invasion, angiogenesis, metastasis, and 5-FU resistance. Smad4 expression in mouse tumours regulated cell-cycle regulatory proteins leading to Rb phosphorylation. Loss of Smad4 activated Akt pathway that resulted in upregulation of anti-apoptotic proteins, Bcl-2 and Bcl-w, and Survivin. Suppression of phosphatidylinositol-3-kinase (PI3K)/Akt pathway by LY294002 restored chemosensitivity of Smad4-deficient cells to 5-FU. Vascular endothelial growth factor-induced angiogenesis in Smad4-deficient cells might also lead to chemoresistance. Low levels of Smad4 expression in CRC tissues correlated with higher levels of Bcl-2 and Bcl-w and with poor overall survival as observed in immunohistochemical staining of tissue microarrays. Loss of Smad4 in CRC patients induces resistance to 5-FU-based therapy through activation of Akt pathway and inhibitors of this pathway may sensitise these patients to 5-FU.

  8. Clinical efficacy of paclitaxel in the treatment of mid-stage and ...

    African Journals Online (AJOL)

    Conclusion: Paclitaxel has a significant effect when used to treat mid-stage and advanced gastric cancer. Moreover, additional nursing not only enhances the therapeutic effect but also improves prognosis and quality-of-life. Keywords: Paclitaxel, Mid-stage/advanced cancer, Gastric cancer, Nursing efficacy, Karnofsky ...

  9. A Liposomal Formulation Able to Incorporate a High Content of Paclitaxel and Exert Promising Anticancer Effect

    Directory of Open Access Journals (Sweden)

    Pei Kan

    2011-01-01

    Full Text Available A liposome formulation for paclitaxel was developed in this study. The liposomes, composed of naturally unsaturated and hydrogenated phosphatidylcholines, with significant phase transition temperature difference, were prepared and characterized. The liposomes exhibited a high content of paclitaxel, which was incorporated within the segregated microdomains coexisting on phospholipid bilayer of liposomes. As much as 15% paclitaxel to phospholipid molar ratio were attained without precipitates observed during preparation. In addition, the liposomes remained stable in liquid form at 4∘C for at least 6 months. The special composition of liposomal membrane which could reduce paclitaxel aggregation could account for such a capacity and stability. The cytotoxicity of prepared paclitaxel liposomes on the colon cancer C-26 cell culture was comparable to Taxol. Acute toxicity test revealed that LD50 for intravenous bolus injection in mice exceeded by 40 mg/kg. In antitumor efficacy study, the prepared liposomal paclitaxel demonstrated the increase in the efficacy against human cancer in animal model. Taken together, the novel formulated liposomes can incorporate high content of paclitaxel, remaining stable for long-term storage. These animal data also demonstrate that the liposomal paclitaxel is promising for further clinical use.

  10. In-vitro release of anti-proliferative paclitaxel from novel balloon-expandable polycaprolactone stents

    International Nuclear Information System (INIS)

    Liu, Shih-Jung; Hsiao, Chao-Ying; Chen, Jan-Kan; Liu, Kuo-Sheng; Lee, Cheng-Hung

    2011-01-01

    This report investigated the in-vitro release characteristics of paclitaxel from novel balloon-expandable polycaprolactone stents. Polycaprolactone stents were first manufactured by a lab-made micro-injection molding machine. Paclitaxel and polylactide-polyglycolide (PLGA) copolymer were dissolved in acetonitrile and were coated onto the surface of the stents by a spray coating device, which was designed and built especially for this study. An elution method was utilized to characterize the in-vitro release characteristics of paclitaxel. The high performance liquid chromatography (HPLC) analysis showed that biodegradable stents could provide sustained release of paclitaxel for more than 70 days. Various process parameters that controlled the release rate of paclitaxel were studied. The experimental results suggested that the total period of drug release could be prolonged by adopting 75:25 PLGA copolymers, employing multi-layer coatings, and increasing the drug loading. In addition, the effectiveness of eluted paclitaxel on cell behavior was examined. The results showed that the eluted drug could effectively inhibit the proliferation of smooth muscle cells. - Research Highlights: → We investigate the in-vitro release characteristics of paclitaxel from polycaprolactone stents. → Biodegradable stents provide sustained release of paclitaxel for more than 70 days. → The eluted drug effectively inhibits the proliferation of smooth muscle cells.

  11. Paclitaxel prodrugs, method for preparation as well as their use in selective chemotherapy

    NARCIS (Netherlands)

    de Bont, Hendricus BA; Leenders, Ruben GG; Scheeren, Johan W; Haisma, Hidde J; de Vos, Dick

    1998-01-01

    A paclitaxel prodrug has a paclitaxel portion coupled to a cleavable N-(aliphatic or aromatic)-O-glycosyl carbamate spacer group, and can be administered orally, topically or by injection to provide an anti-tumor effect, the prodrug being activated by a hydrolizing enzyme, an endogeneous enzyme or

  12. Induced mutation aiming at obtaining lodging resistance in wheat C V.Omid(Triticum Aestivum)

    International Nuclear Information System (INIS)

    Majd, F.; Rezazadeh, M.; Ghohari, A.

    1993-01-01

    Mutation breeding has been an important part breeding research for solving some of the existing problems related to wheat. A locally adopted wheat cultivar 'Omid' which is a traditionally tall wheat mostly cultivated in regions with a continental climate and is susceptible to lodging was chosen as research material. The nuclear research department for agriculture of Atomic Energy Organization of Iran initiated a mutation breeding program for creating genetic variability in wheat using this local cultivar. Seeds of this variety was irradiated with gamma radiation (50-150 Gy) to induce short straw mutants with greater lodging resistance and yield potential. from a total of about 20000 irradiated seeds 1500 plants showing promising agronomic character were isolated as potential mutants. Following progeny tests and selection 18 mutants lines entered preliminary yield trail. Further field trails at different locations gave two promising lines which are characterized by higher yield, lodging resistance and early maturity. (author). 3 tabs

  13. Improved resistance of chemically-modified nanocellulose against thermally-induced depolymerization.

    Science.gov (United States)

    Agustin, Melissa B; Nakatsubo, Fumiaki; Yano, Hiroyuki

    2017-05-15

    The study demonstrated the improvement in the resistance of nanocellulose against thermally-induced depolymerization by esterification with benzoyl (BNZ) and pivaloyl (PIV). The change in the degree of polymerization (DP) and molecular weight distribution (MWD) after thermal treatment in nitrogen and in air was investigated using viscometry and gel permeation chromatography. BNZ and PIV nanocellulose esters without α-hydrogens gave higher DP and narrower MWD than pure bacterial cellulose; and the acetyl and myristoyl esters, which possess α-hydrogens. Results also showed that when depolymerization is suppressed, thermal discoloration is also reduced. Resistance against depolymerization inhibits the formation of reducing ends which can be active sites for thermal discoloration. Finally, the findings suggest that benzoylation and pivaloylation can be an excellent modification technique to improve the thermal stability of nanocellulose. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Application of Glycerol for Induced Powdery Mildew Resistance in Triticum aestivum L.

    Science.gov (United States)

    Li, Yinghui; Song, Na; Zhao, Chuanzhi; Li, Feng; Geng, Miaomiao; Wang, Yuhui; Liu, Wanhui; Xie, Chaojie; Sun, Qixin

    2016-01-01

    Previous work has demonstrated that glycerol-3-phosphate (G3P) and oleic acid (18:1) are two important signal molecules associated with plant resistance to fungi. In this article, we provide evidence that a 3% glycerol spray application 1-2 days before powdery mildew infection and subsequent applications once every 4 days was sufficient to stimulate the plant defense responses without causing any significant damage to wheat leaves. We found that G3P and oleic acid levels were markedly induced by powdery mildew infection. In addition, TaGLI1 (encoding a glycerol kinase) and TaSSI2 (encoding a stearoylacyl carrier protein fatty acid desaturase), two genes associated with the glycerol and fatty acid (FA) pathways, respectively, were induced by powdery mildew infection, and their promoter regions contain some fungal response elements. Moreover, exogenous application of glycerol increased the G3P level and decreased the level of oleic acid (18:1). Glycerol application induced the expression of pathogenesis-related ( PR ) genes ( TaPR-1, TaPR-2, TaPR-3, TaPR-4 , and TaPR-5 ), induced the generation of reactive oxygen species (ROS) before powdery mildew infection, and induced salicylic acid (SA) accumulation in wheat leaves. Further, we sprayed glycerol in a wheat field and found that it significantly ( p powdery mildew disease and lessened disease-associated kernel weight loss, all without causing any noticeable degradation in wheat seed quality.

  15. Vorinostat-induced autophagy switches from a death-promoting to a cytoprotective signal to drive acquired resistance.

    Science.gov (United States)

    Dupéré-Richer, D; Kinal, M; Ménasché, V; Nielsen, T H; Del Rincon, S; Pettersson, F; Miller, W H

    2013-02-07

    Histone deacetylase inhibitors (HDACi) have shown promising activity against hematological malignancies in clinical trials and have led to the approval of vorinostat for the treatment of cutaneous T-cell lymphoma. However, de novo or acquired resistance to HDACi therapy is inevitable, and their molecular mechanisms are still unclear. To gain insight into HDACi resistance, we developed vorinostat-resistant clones from the hematological cell lines U937 and SUDHL6. Although cross-resistant to some but not all HDACi, the resistant cell lines exhibit dramatically increased sensitivity toward chloroquine, an inhibitor of autophagy. Consistent with this, resistant cells growing in vorinostat show increased autophagy. Inhibition of autophagy in vorinostat-resistant U937 cells by knockdown of Beclin-1 or Lamp-2 (lysosome-associated membrane protein 2) restores sensitivity to vorinostat. Interestingly, autophagy is also activated in parental U937 cells by de novo treatment with vorinostat. However, in contrast to the resistant cells, inhibition of autophagy decreases sensitivity to vorinostat. These results indicate that autophagy can switch from a proapoptotic signal to a prosurvival function driving acquired resistance. Moreover, inducers of autophagy (such as mammalian target of rapamycin inhibitors) synergize with vorinostat to induce cell death in parental cells, whereas the resistant cells remain insensitive. These data highlight the complexity of the design of combination strategies using modulators of autophagy and HDACi for the treatment of hematological malignancies.

  16. 2-deoxy-D-glucose-induced metabolic stress enhances resistance to Listeria monocytogenes infection in mice

    Science.gov (United States)

    Miller, E. S.; Bates, R. A.; Koebel, D. A.; Fuchs, B. B.; Sonnenfeld, G.

    1998-01-01

    Exposure to different forms of psychological and physiological stress can elicit a host stress response, which alters normal parameters of neuroendocrine homeostasis. The present study evaluated the influence of the metabolic stressor 2-deoxy-D-glucose (2-DG; a glucose analog, which when administered to rodents, induces acute periods of metabolic stress) on the capacity of mice to resist infection with the facultative intracellular bacterial pathogen Listeria monocytogenes. Female BDF1 mice were injected with 2-DG (500 mg/kg b. wt.) once every 48 h prior to, concurrent with, or after the onset of a sublethal dose of virulent L. monocytogenes. Kinetics of bacterial growth in mice were not altered if 2-DG was applied concurrently or after the start of the infection. In contrast, mice exposed to 2-DG prior to infection demonstrated an enhanced resistance to the listeria challenge. The enhanced bacterial clearance in vivo could not be explained by 2-DG exerting a toxic effect on the listeria, based on the results of two experiments. First, 2-DG did not inhibit listeria replication in trypticase soy broth. Second, replication of L. monocytogenes was not inhibited in bone marrow-derived macrophage cultures exposed to 2-DG. Production of neopterin and lysozyme, indicators of macrophage activation, were enhanced following exposure to 2-DG, which correlated with the increased resistance to L. monocytogenes. These results support the contention that the host response to 2-DG-induced metabolic stress can influence the capacity of the immune system to resist infection by certain classes of microbial pathogens.

  17. The nitrogen availability interferes with mycorrhiza-induced resistance against Botrytis cinerea in tomato

    Directory of Open Access Journals (Sweden)

    Paloma Sanchez-Bel

    2016-10-01

    Full Text Available Mycorrhizal plants are generally quite efficient in coping with environmental challenges. It has been shown that the symbiosis with arbuscular mycorrhizal fungi (AMF can confer resistance against root and foliar pathogens, although the molecular mechanisms underlying such mycorrhiza-induced resistance (MIR are poorly understood. Tomato plants colonized with the AMF Rhizophagus irregularis display enhanced resistance against the necrotrophic foliar pathogen Botrytis cinerea. Leaves from arbuscular mycorrhizal (AM plants develop smaller necrotic lesions, mirrored also by a reduced levels of fungal biomass. A plethora of metabolic changes takes place in AMF colonized plants upon infection. Certain changes located in the oxylipin pathway indicate that several intermediaries are over-accumulated in the AM upon infection. AM plants react by accumulating higher levels of the vitamins folic acid and riboflavin, indolic derivatives and phenolic compounds such as ferulic acid and chlorogenic acid. Transcriptional analysis support the key role played by the LOX pathway in the shoots associated with MIR against B. cinerea.Interestingly, plants that have suffered a short period of nitrogen starvation appear to react by reprogramming their metabolic and genetic responses by prioritizing abiotic stress tolerance. Consequently, plants subjected to a transient nitrogen depletion become more susceptible to B. cinerea. Under these experimental conditions, MIR is severely affected although still functional. Many metabolic and transcriptional responses which are accumulated or activated by MIR such NRT2 transcript induction and OPDA and most Trp and indolic derivatives accumulation during MIR were repressed or reduced when tomato plants were depleted of N for 48 h prior infection. These results highlight the beneficial roles of AMF in crop protection by promoting induced resistance not only under optimal nutritional conditions but also buffering the susceptibility

  18. Diet-induced obesity causes ghrelin resistance in reward processing tasks.

    Science.gov (United States)

    Lockie, Sarah H; Dinan, Tara; Lawrence, Andrew J; Spencer, Sarah J; Andrews, Zane B

    2015-12-01

    Diet-induced obesity (DIO) causes ghrelin resistance in hypothalamic Agouti-related peptide (AgRP) neurons. However, ghrelin promotes feeding through actions at both the hypothalamus and mesolimbic dopamine reward pathways. Therefore, we hypothesized that DIO would also establish ghrelin resistance in the ventral tegmental area (VTA), a major site of dopaminergic cell bodies important in reward processing. We observed reduced sucrose and saccharin consumption in Ghrelin KO vs Ghrelin WT mice. Moreover, DIO reduced saccharin consumption relative to chow-fed controls. These data suggest that the deletion of ghrelin and high fat diet both cause anhedonia. To assess if these are causally related, we tested whether DIO caused ghrelin resistance in a classic model of drug reward, conditioned place preference (CPP). Chow or high fat diet (HFD) mice were conditioned with ghrelin (1mg/kg in 10ml/kg ip) in the presence or absence of food in the conditioning chamber. We observed a CPP to ghrelin in chow-fed mice but not in HFD-fed mice. HFD-fed mice still showed a CPP for cocaine (20mg/kg), indicating that they maintained the ability to develop conditioned behaviour. The absence of food availability during ghrelin conditioning sessions induced a conditioned place aversion, an effect that was still present in both chow and HFD mice. Bilateral intra-VTA ghrelin injection (0.33μg/μl in 0.5μl) robustly increased feeding in both chow-fed and high fat diet (HFD)-fed mice; however, this was correlated with body weight only in the chow-fed mice. Our results suggest that DIO causes ghrelin resistance albeit not directly in the VTA. We suggest there is impaired ghrelin sensitivity in upstream pathways regulating reward pathways, highlighting a functional role for ghrelin linking appropriate metabolic sensing with reward processing. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Informed herbivore movement and interplant communication determine the effects of induced resistance in an individual-based model.

    Science.gov (United States)

    Rubin, Ilan N; Ellner, Stephen P; Kessler, André; Morrell, Kimberly A

    2015-09-01

    1. Plant induced resistance to herbivory affects the spatial distribution of herbivores, as well as their performance. In recent years, theories regarding the benefit to plants of induced resistance have shifted from ideas of optimal resource allocation towards a more eclectic set of theories that consider spatial and temporal plant variability and the spatial distribution of herbivores among plants. However, consensus is lacking on whether induced resistance causes increased herbivore aggregation or increased evenness, as both trends have been experimentally documented. 2. We created a spatial individual-based model that can describe many plant-herbivore systems with induced resistance, in order to analyse how different aspects of induced resistance might affect herbivore distribution, and the total damage to a plant population, during a growing season. 3. We analyse the specific effects on herbivore aggregation of informed herbivore movement (preferential movement to less-damaged plants) and of information transfer between plants about herbivore attacks, in order to identify mechanisms driving both aggregation and evenness. We also investigate how the resulting herbivore distributions affect the total damage to plants and aggregation of damage. 4. Even, random and aggregated herbivore distributions can all occur in our model with induced resistance. Highest levels of aggregation occurred in the models with informed herbivore movement, and the most even distributions occurred when the average number of herbivores per plant was low. With constitutive resistance, only random distributions occur. Damage to plants was spatially correlated, unless plants recover very quickly from damage; herbivore spatial autocorrelation was always weak. 5. Our model and results provide a simple explanation for the apparent conflict between experimental results, indicating that both increased aggregation and increased evenness of herbivores can result from induced resistance. We

  20. Advanced ovarian cancer: phase III randomized study of sequential cisplatin-topotecan and carboplatin-paclitaxel vs carboplatin-paclitaxel.

    Science.gov (United States)

    Hoskins, P; Vergote, I; Cervantes, A; Tu, D; Stuart, G; Zola, P; Poveda, A; Provencher, D; Katsaros, D; Ojeda, B; Ghatage, P; Grimshaw, R; Casado, A; Elit, L; Mendiola, C; Sugimoto, A; D'Hondt, V; Oza, A; Germa, J R; Roy, M; Brotto, L; Chen, D; Eisenhauer, E A

    2010-10-20

    Topotecan has single-agent activity in recurrent ovarian cancer. It was evaluated in a novel combination compared with standard frontline therapy. Women aged 75 years or younger with newly diagnosed stage IIB or greater ovarian cancer, Eastern Cooperative Oncology Group Performance Status of 1 or less, were stratified by type of primary surgery and residual disease, treatment center, and age; then randomly assigned to one of the two 21-day intravenous regimens. Patients in arm 1 (n = 409) were administered four cycles of cisplatin 50 mg/m(2) on day 1 and topotecan 0.75 mg/m(2) on days 1-5, then four cycles of paclitaxel 175 mg/m(2) over 3 hours on day 1 followed by carboplatin (area under the curve = 5) on day 1. Patients in arm 2 (n = 410) were given paclitaxel plus carboplatin as in arm 1 for eight cycles. We compared progression-free survival (PFS), overall survival, and cancer antigen-125 normalization rates in the two treatment arms. A stratified log-rank test was used to assess the primary endpoint, PFS. All statistical tests were two-sided. A total of 819 patients were randomly assigned. At baseline, the median age of the patients was 57 years (range = 28-78); 81% had received debulking surgery, and of these, 55% had less than 1 cm residual disease; 66% of patients were stage III and 388 (47.4%) patients had measurable disease. After a median follow-up of 43 months, 650 patients had disease progression or died without documented progression and 406 had died. Patients in arm 1 had more hematological toxicity and hospitalizations than patients in arm 2; PFS was 14.6 months in arm 1 vs 16.2 months in arm 2 (hazard ratio = 1.10, 95% confidence interval = 0.94 to 1.28, P = .25). Among patients with elevated baseline cancer antigen-125, fewer in arm 1 than in arm 2 had levels return to normal by 3 months after random assignment (51.6% vs 63.3%, P = .007) Topotecan and cisplatin, followed by carboplatin and paclitaxel, were more toxic than carboplatin and

  1. Curcumin induces apoptosis and protective autophagy in castration-resistant prostate cancer cells through iron chelation

    Directory of Open Access Journals (Sweden)

    Yang C

    2017-02-01

    Full Text Available Chunguang Yang,1,* Xueyou Ma,1,* Zhihua Wang,1 Xing Zeng,1 Zhiquan Hu,1 Zhangqun Ye,1 Guanxin Shen2 1Department of Urology, Tongji Hospital, 2Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People’s Republic of China *These authors contributed equally to this work Background: Curcumin induces apoptosis and autophagy in different cancer cells. Moreover, chemical and biological experiments have evidenced that curcumin is a biologically active iron chelator and induces cytotoxicity through iron chelation. We thus hypothesized that curcumin may induce apoptosis and autophagy in castration-resistant prostate cancer (CRPC cells through its iron-chelating properties.Materials and methods: CRPC cells were loaded with curcumin alone or in combination with ferric ammonium citrate (FAC. Cytotoxicity was measured by 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay. Apoptosis was assessed by flow cytometry, terminal deoxynucleotidyl transferase nick end labeling (TUNEL assay and caspase activity. Autophagy status was analyzed by the detection of autophagosomes and light chain 3-II (LC3-II using transmission electron microscopy and Western blot. Iron-binding activity of curcumin was assessed by spectrophotometry and MTT assay. The expression levels of transferrin receptor 1 (TfR1 and iron regulatory protein 1 (IRP1 were examined by Western blot.Results: Curcumin induced apoptosis and autophagy in CRPC cells. Combining curcumin with autophagy inhibitors (3-methyladenine [3-MA] synergized the apoptotic effect of curcumin. Moreover, curcumin bound to FAC at a ratio of ~1:1, as assessed by spectrophotometry and MTT assay. Apoptosis and autophagy induced by curcumin were counteracted by equal amounts of FAC. At apoptosis- and autophagy-inducing concentrations, curcumin enhanced the expression levels of TfR1 and IRP1, indicative of iron deprivation induced by curcumin

  2. Severe hypoxia induces chemo-resistance in clinical cervical tumors through MVP over-expression.

    Science.gov (United States)

    Lara, Pedro C; Lloret, Marta; Clavo, Bernardino; Apolinario, Rosa M; Henríquez-Hernández, Luis Alberto; Bordón, Elisa; Fontes, Fausto; Rey, Agustín

    2009-08-06

    Oxygen molecule modulates tumour response to radiotherapy. Higher radiation doses are required under hypoxic conditions to induce cell death. Hypoxia may inhibit the non-homologous end-joining DNA repair through down regulating Ku70/80 expression. Hypoxia induces drug resistance in clinical tumours, although the mechanism is not clearly elucidated. Vaults are ribonucleoprotein particles with a hollow barrel-like structure composed of three proteins: major vault protein (MVP), vault poly(ADP-ribose) polymerase, and telomerase associated protein-1 and small untranslated RNA. Over-expression of MVP has been associated with chemotherapy resistance. Also, it has been related to poor outcome in patients treated with radiotherapy alone. The aim of the present study was to assess the relation of Major Vault Protein expression and tumor hypoxia in clinical cervical tumors. MVP, p53 and angiogenesis, together with tumor oxygenation, were determined in forty-three consecutive patients suffering from localized cervix carcinoma. High MVP expression was related to severe hypoxia compared to low MVP expressing tumors (p = 0.022). Tumors over-expressing MVP also showed increased angiogenesis (p = 0.003). Besides it, in this study we show for the first time that severe tumor hypoxia is associated with high MVP expression in clinical cervical tumors. Up-regulation of MVP by hypoxia is of critical relevance as chemotherapy is currently a standard treatment for those patients. From our results it could be suggested that hypoxia not only induces increased genetic instability, oncogenic properties and metastatization, but through the correlation observed with MVP expression, another pathway of chemo and radiation resistance could be developed.

  3. Severe hypoxia induces chemo-resistance in clinical cervical tumors through MVP over-expression

    International Nuclear Information System (INIS)

    Lara, Pedro C; Lloret, Marta; Clavo, Bernardino; Apolinario, Rosa M; Henríquez-Hernández, Luis Alberto; Bordón, Elisa; Fontes, Fausto; Rey, Agustín

    2009-01-01

    Oxygen molecule modulates tumour response to radiotherapy. Higher radiation doses are required under hypoxic conditions to induce cell death. Hypoxia may inhibit the non-homologous end-joining DNA repair through down regulating Ku70/80 expression. Hypoxia induces drug resistance in clinical tumours, although the mechanism is not clearly elucidated. Vaults are ribonucleoprotein particles with a hollow barrel-like structure composed of three proteins: major vault protein (MVP), vault poly(ADP-ribose) polymerase, and telomerase associated protein-1 and small untranslated RNA. Over-expression of MVP has been associated with chemotherapy resistance. Also, it has been related to poor outcome in patients treated with radiotherapy alone. The aim of the present study was to assess the relation of Major Vault Protein expression and tumor hypoxia in clinical cervical tumors. MVP, p53 and angiogenesis, together with tumor oxygenation, were determined in forty-three consecutive patients suffering from localized cervix carcinoma. High MVP expression was related to severe hypoxia compared to low MVP expressing tumors (p = 0.022). Tumors over-expressing MVP also showed increased angiogenesis (p = 0.003). Besides it, in this study we show for the first time that severe tumor hypoxia is associated with high MVP expression in clinical cervical tumors. Up-regulation of MVP by hypoxia is of critical relevance as chemotherapy is currently a standard treatment for those patients. From our results it could be suggested that hypoxia not only induces increased genetic instability, oncogenic properties and metastatization, but through the correlation observed with MVP expression, another pathway of chemo and radiation resistance could be developed

  4. Obestatin regulates adipocyte function and protects against diet-induced insulin resistance and inflammation.

    Science.gov (United States)

    Granata, Riccarda; Gallo, Davide; Luque, Raul M; Baragli, Alessandra; Scarlatti, Francesca; Grande, Cristina; Gesmundo, Iacopo; Córdoba-Chacón, Jose; Bergandi, Loredana; Settanni, Fabio; Togliatto, Gabriele; Volante, Marco; Garetto, Stefano; Annunziata, Marta; Chanclón, Belén; Gargantini, Eleonora; Rocchietto, Stefano; Matera, Lina; Datta, Giacomo; Morino, Mario; Brizzi, Maria Felice; Ong, Huy; Camussi, Giovanni; Castaño, Justo P; Papotti, Mauro; Ghigo, Ezio

    2012-08-01

    The metabolic actions of the ghrelin gene-derived peptide obestatin are still unclear. We investigated obestatin effects in vitro, on adipocyte function, and in vivo, on insulin resistance and inflammation in mice fed a high-fat diet (HFD). Obestatin effects on apoptosis, differentiation, lipolysis, and glucose uptake were determined in vitro in mouse 3T3-L1 and in human subcutaneous (hSC) and omental (hOM) adipocytes. In vivo, the influence of obestatin on glucose metabolism was assessed in mice fed an HFD for 8 wk. 3T3-L1, hSC, and hOM preadipocytes and adipocytes secreted obestatin and showed specific binding for the hormone. Obestatin prevented apoptosis in 3T3-L1 preadipocytes by increasing phosphoinositide 3-kinase (PI3K)/Akt and extracellular signal-regulated kinase (ERK)1/2 signaling. In both mice and human adipocytes, obestatin inhibited isoproterenol-induced lipolysis, promoted AMP-activated protein kinase phosphorylation, induced adiponectin, and reduced leptin secretion. Obestatin also enhanced glucose uptake in either the absence or presence of insulin, promoted GLUT4 translocation, and increased Akt phosphorylation and sirtuin 1 (SIRT1) protein expression. Inhibition of SIRT1 by small interfering RNA reduced obestatin-induced glucose uptake. In HFD-fed mice, obestatin reduced insulin resistance, increased insulin secretion from pancreatic islets, and reduced adipocyte apoptosis and inflammation in metabolic tissues. These results provide evidence of a novel role for obestatin in adipocyte function and glucose metabolism and suggest potential therapeutic perspectives in insulin resistance and metabolic dysfunctions.

  5. Direct current (DC) resistivity and Induced Polarization (IP) monitoring of active layer dynamics at high temporal resolution

    DEFF Research Database (Denmark)

    Doetsch, J.; Fiandaca, G.; Ingeman-Nielsen, Thomas

    2015-01-01

    With permafrost thawing and changes in active layer dynamics induced by climate change, interactions between biogeochemical and thermal processes in the ground are of great importance. Here, active layer dynamics have been monitored using direct current (DC) resistivity and induced polarization (IP...... the soil freezing as a strong increase in resistivity. While the freezing horizon generally moves deeper with time, some variations in the freezing depth are observed along the profile. Comparison with depth-specific soil temperature indicates an exponential relationship between resistivity and below...

  6. Direct current (DC) resistivity and induced polarization (IP) monitoring of active layer dynamics at high temporal resolution

    DEFF Research Database (Denmark)

    Doetsch, Joseph; Ingeman-Nielsen, Thomas; Christiansen, Anders V.

    2015-01-01

    With permafrost thawing and changes in active layer dynamics induced by climate change, interactions between biogeochemical and thermal processes in the ground are of great importance. Here, active layer dynamics have been monitored using direct current (DC) resistivity and induced polarization (IP...... in resistivity. While the freezing horizon generally moves deeper with time, some variations in the freezing depth are observed along the profile. Comparison with depth-specific soil temperature indicates an exponential relationship between resistivity and below-freezing temperature. Time-lapse inversions...

  7. Resistance to diet-induced obesity and associated metabolic perturbations in haploinsufficient monocarboxylate transporter 1 mice.

    OpenAIRE

    Lengacher Sylvain; Nehiri-Sitayeb Touria; Steiner Nadia; Carneiro Lionel; Favrod Céline; Preitner Frédéric; Thorens Bernard; Stehle Jean-Christophe; Dix Laure; Pralong François; Magistretti Pierre J; Pellerin Luc

    2013-01-01

    The monocarboxylate transporter 1 (MCT1 or SLC16A1) is a carrier of short-chain fatty acids, ketone bodies, and lactate in several tissues. Genetically modified C57BL/6J mice were produced by targeted disruption of the mct1 gene in order to understand the role of this transporter in energy homeostasis. Null mutation was embryonically lethal, but MCT1(+/-) mice developed normally. However, when fed high fat diet (HFD), MCT1(+/-) mice displayed resistance to development of diet-induced obesity ...

  8. Attempts to induce mutations for resistance of wheat to mildew, stem rust and leaf rust

    International Nuclear Information System (INIS)

    Kiraly, Z.; Barabas, Z.

    1983-01-01

    Research carried out between 1971 and 1981 is summarized. Attempts to find induced mutants with full resistance to pathotype mixtures of the three pathogens were not successful. Reasons are discussed. Studies on wheat lines tolerant to stem rust infection led to the conclusion that this disease reaction may be often accompanied by a reduced number of infection sites and a longer lag period resulting in reduced spore production. Various selection methods have been evaluated. Selecting for the multigenic 'non race specific' way is promising. (author)

  9. Passive measurement of flux nucleation in the current-induced resistive state of type I superconductors

    International Nuclear Information System (INIS)

    Selig, K.P.; Chimenti, D.E.; Huebener, R.P.

    1978-01-01

    Flux-tube nucleation rates have been measured in the current-induced resistive state of type I superconducting In films between 1.5 and 2.0 K by a completely passive technique. Indication of periodic nucleation is observed only in narrow regions of sample voltage drop, whose position is a sensitive function of temperature. Frequency bandwidth measurements of the nucleation rate yield a spectral purity of one part in 10 4 within the narrow regions where an experimental signal can be detected. (orig.) [de

  10. Results of induction chemotherapy followed by three-dimensional conformal radiotherapy and concurrent weekly paclitaxel for stage III non-small cell lung cancer

    International Nuclear Information System (INIS)

    Wang Weihua; Bao Yong; Chen Ming; Zhang Li; Xu Guangchuan; Li Kaixin

    2008-01-01

    Objective: To evaluate the toxicity and efficacy of induction chemotherapy (ICT) followed by three-dimensional conformal radiotherapy (3DCRT) plus concurrent weekly paclitaxel for inoperable non-small cell lung cancer (NSCLC). Methods: Patients with stage III NSCLC in favorable conditions were treated with 2 to 4 cycles of carboplatin (AUC=5-6, d1) combined with paclitaxel (175 mg/m 2 , d1), then followed by weekly paclitaxel (40 mg/m 2 ) and concurrent 3DCRT within 34 weeks. The prescription dose of radiotherapy was given as high as possible while total lung V 20 ≤31% and total dose of the spinal cord ≤50 Gy. Results: ICT was well tolerated. During the concurrent chemoradiotherapy,the treatment of 4 patients was ended ahead of the schedule because of severe pulmonary and cardiac toxicities; the treatment of 2 patients was delayed for 7 and 12 days because of fatigue. Leucopenia(33/56) was in grade 1-2 except 1 patient in grade 3. Lymphocytopenia was severe (54/56,42 in grade 3). Three patients developed grade 3 acute radiation-induced esophagitis, and 3 developed grade 3-4 radiation-induced pneumonitis. There was one patients each who developed grade 2,3, and 4 late esophageal damage, respectively. Nine developed grade 2 pulmonary fibrosis. The overall response rate was 69.7%. The 1-year overall survival rate was 72.3%. The 1-year local progression-free survival rate was 62.7%. Conclusions: The schedule of ICT followed by weekly paclitaxel and concurrent 3DCRT can be well tolerated by most of the favorable patients with stage III NSCLC, and the toxicity is tolerable. Results of this study are encouraging, though long-term results should be followed up. (authors)

  11. Understanding the molecular mechanism(s) of hepatitis C virus (HCV) induced interferon resistance.

    Science.gov (United States)

    Qashqari, Hanadi; Al-Mars, Amany; Chaudhary, Adeel; Abuzenadah, Adel; Damanhouri, Ghazi; Alqahtani, Mohammed; Mahmoud, Maged; El Sayed Zaki, Maysaa; Fatima, Kaneez; Qadri, Ishtiaq

    2013-10-01

    Hepatitis C virus (HCV) is one of the foremost causes of chronic liver disease affecting over 300 million globally. HCV contains a positive-stranded RNA of ~9600 nt and is surrounded by the 5' and 3'untranslated regions (UTR). The only successful treatment regimen includes interferon (IFN) and ribavirin. Like many other viruses, HCV has also evolved various mechanisms to circumvent the IFN response by blocking (1) downstream signaling actions via STAT1, STAT2, IRF9 and JAK-STAT pathways and (2) repertoire of IFN Stimulatory Genes (ISGs). Several studies have identified complex host demographic and genetic factors as well as viral genetic heterogeneity associated with outcomes of IFN therapy. The genetic predispositions of over 2000 ISGS may render the patients to become resistant, thus identification of such parameters within a subset of population are necessary for management corollary. The ability of various HCV genotypes to diminish IFN antiviral responses plays critical role in the establishment of chronic infection at the acute stage of infection, thus highlighting importance of the resistance in HCV treated groups. The recently defined role of viral protein such as C, E2, NS3/NS4 and NS5A proteins in inducing the IFN resistance are discussed in this article. How the viral and host genetic composition and epistatic connectivity among polymorphic genomic sites synchronizes the evolutionary IFN resistance trend remains under investigation. However, these signals may have the potential to be employed for accurate prediction of therapeutic outcomes. In this review article, we accentuate the significance of host and viral components in IFN resistance with the aim to determine the successful outcome in patients. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Src mediates cigarette smoke-induced resistance to tyrosine kinase inhibitors in NSCLC cells.

    Science.gov (United States)

    Filosto, Simone; Baston, David S; Chung, Samuel; Becker, Cathleen R; Goldkorn, Tzipora

    2013-08-01

    The EGF receptor (EGFR) is a proto-oncogene commonly dysregulated in several cancers including non-small cell lung carcinoma (NSCLC) and, thus, is targeted for treatment using tyrosine kinase inhibitors (TKI) such as erlotinib. However, despite the efficacy observed in patients with NSCLC harboring oncogenic variants of the EGFR, general ineffectiveness of TKIs in patients with NSCLC who are current and former smokers necessitates identification of novel mechanisms to overcome this phenomenon. Previously, we showed that NSCLC cells harboring either wild-type (WT) EGFR or oncogenic mutant (MT) L858R EGFR become resistant to the effects of TKIs when exposed to cigarette smoke, evidenced by their autophosphorylation and prolonged downstream signaling. Here, we present Src as a target mediating cigarette smoke-induced resistance to TKIs in both WT EGFR- and L858R MT EGFR-expressing NSCLC cells. First, we show that cigarette smoke exposure of A549 cells leads to time-dependent activation of Src, which then abnormally binds to the WT EGFR causing TKI resistance, contrasting previous observations of constitutive binding between inactive Src and TKI-sensitive L858R MT EGFR. Next, we show that Src inhibition restores TKI sensitivity in cigarette smoke-exposed NSCLC cells, preventing EGFR autophosphorylation in the presence of erlotinib. Furthermore, we show that overexpression of a dominant-negative Src (Y527F/K295R) restores TKI sensitivity to A549 exposed to cigarette smoke. Importantly, the TKI resistance that emerges even in cigarette smoke-exposed L858R EGFR-expressing NSCLC cells could be eliminated with Src inhibition. Together, these findings offer new rationale for using Src inhibitors for treating TKI-resistant NSCLC commonly observed in smokers.

  13. Current-induced forces: a new mechanism to induce negative differential resistance and current-switching effect in molecular junctions

    Science.gov (United States)

    Gu, Lei; Fu, Hua-Hua

    2015-12-01

    Current-induced forces can excite molecules, polymers and other low-dimensional materials, which in turn leads to an effective gate voltage through Holstein interaction. Here, by taking a short asymmetric DNA junction as an example, and using the Langevin approach, we find that when suppression of charge transport by the effective gate voltage surpasses the current increase from an elevated voltage bias, the current-voltage (I-V) curves display strong negative differential resistance (NDR) and perfect current-switching characteristics. The asymmetric DNA chain differs in mechanical stability under inverse voltages and the I-V curve is asymmetric about inverse biases, which can be used to understand recent transport experiments on DNA chains, and meanwhile provides a new strategy to realize NDR in molecular junctions and other low-dimensional quantum systems.

  14. Current-induced forces: a new mechanism to induce negative differential resistance and current-switching effect in molecular junctions

    International Nuclear Information System (INIS)

    Gu, Lei; Fu, Hua-Hua

    2015-01-01

    Current-induced forces can excite molecules, polymers and other low-dimensional materials, which in turn leads to an effective gate voltage through Holstein interaction. Here, by taking a short asymmetric DNA junction as an example, and using the Langevin approach, we find that when suppression of charge transport by the effective gate voltage surpasses the current increase from an elevated voltage bias, the current-voltage (I–V) curves display strong negative differential resistance (NDR) and perfect current-switching characteristics. The asymmetric DNA chain differs in mechanical stability under inverse voltages and the I–V curve is asymmetric about inverse biases, which can be used to understand recent transport experiments on DNA chains, and meanwhile provides a new strategy to realize NDR in molecular junctions and other low-dimensional quantum systems. (paper)

  15. Skeletal Muscle TRIB3 Mediates Glucose Toxicity in Diabetes and High- Fat Diet–Induced Insulin Resistance

    Science.gov (United States)

    Wu, Mengrui; Kim, Teayoun; Jariwala, Ravi H.; Garvey, W. John; Luo, Nanlan; Kang, Minsung; Ma, Elizabeth; Tian, Ling; Steverson, Dennis; Yang, Qinglin; Fu, Yuchang

    2016-01-01

    In the current study, we used muscle-specific TRIB3 overexpressing (MOE) and knockout (MKO) mice to determine whether TRIB3 mediates glucose-induced insulin resistance in diabetes and whether alterations in TRIB3 expression as a function of nutrient availability have a regulatory role in metabolism. In streptozotocin diabetic mice, TRIB3 MOE exacerbated, whereas MKO prevented, glucose-induced insulin resistance and impaired glucose oxidation and defects in insulin signal transduction compared with wild-type (WT) mice, indicating that glucose-induced insulin resistance was dependent on TRIB3. In response to a high-fat diet, TRIB3 MOE mice exhibited greater weight gain and worse insulin resistance in vivo compared with WT mice, coupled with decreased AKT phosphorylation, increased inflammation and oxidative stress, and upregulation of lipid metabolic genes coupled with downregulation of glucose metabolic genes in skeletal muscle. These effects were prevented in the TRIB3 MKO mice relative to WT mice. In conclusion, TRIB3 has a pathophysiological role in diabetes and a physiological role in metabolism. Glucose-induced insulin resistance and insulin resistance due to diet-induced obesity both depend on muscle TRIB3. Under physiological conditions, muscle TRIB3 also influences energy expenditure and substrate metabolism, indicating that the decrease and increase in muscle TRIB3 under fasting and nutrient excess, respectively, are critical for metabolic homeostasis. PMID:27207527

  16. Down-regulation of HSP27 sensitizes TRAIL-resistant tumor cell to TRAIL-induced apoptosis

    DEFF Research Database (Denmark)

    Zhuang, Hongqin; Jiang, Weiwei; Cheng, Wei

    2010-01-01

    Tumor necrosis factor-alpha-related apoptosis-inducing ligand (TRAIL) has recently emerged as a cancer therapeutic agent because it preferentially induces apoptosis in human cancer over normal cells. Most tumor cells, including lung cancer cell line A549, unfortunately, are resistant to TRAIL tre...

  17. Co-delivery of paclitaxel and cetuximab by nanodiamond enhances mitotic catastrophe and tumor inhibition.

    Science.gov (United States)

    Lin, Yu-Wei; Raj, Emmanuel Naveen; Liao, Wei-Siang; Lin, Johnson; Liu, Kuang-Kai; Chen, Ting-Hua; Cheng, Hsiao-Chun; Wang, Chi-Ching; Li, Lily Yi; Chen, Chinpiao; Chao, Jui-I

    2017-08-29

    The poor intracellular uptake and non-specific binding of anticancer drugs into cancer cells are the bottlenecks in cancer therapy. Nanocarrier platforms provide the opportunities to improve the drug efficacy. Here we show a carbon-based nanomaterial nanodiamond (ND) that carried paclitaxel (PTX), a microtubule inhibitor, and cetuximab (Cet), a specific monoclonal antibody against epidermal growth factor receptor (EGFR), inducing mitotic catastrophe and tumor inhibition in human colorectal cancer (CRC). ND-PTX blocked the mitotic progression, chromosomal separation, and induced apoptosis in the CRC cells; however, NDs did not induce these effects. Conjugation of ND-PTX with Cet (ND-PTX-Cet) was specifically binding to the EGFR-positive CRC cells and enhanced the mitotic catastrophe and apoptosis induction. Besides, ND-PTX-Cet markedly decreased tumor size in the xenograft EGFR-expressed human CRC tumors of nude mice. Moreover, ND-PTX-Cet induced the mitotic marker protein phospho-histone 3 (Ser10) and apoptotic protein active-caspase 3 for mitotic catastrophe and apoptosis. Taken together, this study demonstrated that the co-delivery of PTX and Cet by ND enhanced the effects of mitotic catastrophe and apoptosis in vitro and in vivo, which may be applied in the human CRC therapy.

  18. Effect of gender on lipid-induced insulin resistance in obese subjects

    DEFF Research Database (Denmark)

    Vistisen, Bodil; Hellgren, Lars; Vadset, T.

    2008-01-01

    Objective: In obese subjects, chronically elevated plasma concentrations of non-esterified fatty acids (NEFAs) exert a marked risk to contract insulin resistance and subsequently type 2 diabetes. When NEFA is acutely increased due to i.v. infusion of lipid, glucose disposal during...... a hyperinsulinemic-euglycemic clamp is reduced. This effect has been explained by a NEFA-induced decrease in skeletal muscle insulin sensitivity caused by accumulation of the lipid intermediates Such as ceramide and diacylglycerol in the myocytes. However, neither the lipid-induced reduction of glucose disposal nor...... the clamp was similar in females and males (46+/-10 and 60+/-4%,, respectively, NS). However, whole-body insulin sensitivity as well as non-oxidative glucose disposal was higher in obese females compared with obese males both during lipid and saline infusion (P...

  19. Flurbiprofen ameliorated obesity by attenuating leptin resistance induced by endoplasmic reticulum stress.

    Science.gov (United States)

    Hosoi, Toru; Yamaguchi, Rie; Noji, Kikuko; Matsuo, Suguru; Baba, Sachiko; Toyoda, Keisuke; Suezawa, Takahiro; Kayano, Takaaki; Tanaka, Shinpei; Ozawa, Koichiro

    2014-03-01

    Endoplasmic reticulum (ER) stress, caused by the accumulation of unfolded proteins, is involved in the development of obesity. We demonstrated that flurbiprofen, a nonsteroidal anti-inflammatory drug (NSAID), exhibited chaperone activity, which reduced protein aggregation and alleviated ER stress-induced leptin resistance, characterized by insensitivity to the actions of the anti-obesity hormone leptin. This result was further supported by flurbiprofen attenuating high-fat diet-induced obesity in mice. The other NSAIDs tested did not exhibit such effects, which suggested that this anti-obesity action is mediated independent of NSAIDs. Using ferriteglycidyl methacrylate beads, we identified aldehyde dehydrogenase as the target of flurbiprofen, but not of the other NSAIDs. These results suggest that flurbiprofen may have unique pharmacological properties that reduce the accumulation of unfolded proteins and may represent a new class of drug for the fundamental treatment of obesity.

  20. Hypothalamic CaMKKβ mediates glucagon anorectic effect and its diet-induced resistance

    Science.gov (United States)

    Quiñones, Mar; Al-Massadi, Omar; Gallego, Rosalía; Fernø, Johan; Diéguez, Carlos; López, Miguel; Nogueiras, Ruben

    2015-01-01

    Objective Glucagon receptor antagonists and humanized glucagon antibodies are currently studied as promising therapies for obesity and type II diabetes. Among its variety of actions, glucagon reduces food intake, but the molecular mechanisms mediating this effect as well as glucagon resistance are totally unknown. Methods Glucagon and adenoviral vectors were administered in specific hypothalamic nuclei of lean and diet-induced obese rats. The expression of neuropeptides controlling food intake was performed by in situ hybridization. The regulation of factors of the glucagon signaling pathway was assessed by western blot. Results The central injection of glucagon decreased feeding through a hypothalamic pathway involving protein kinase A (PKA)/Ca2+-calmodulin-dependent protein kinase kinase β (CaMKKβ)/AMP-activated protein kinase (AMPK)-dependent mechanism. More specifically, the central injection of glucagon increases PKA activity and reduces protein levels of CaMKKβ and its downstream target phosphorylated AMPK in the hypothalamic arcuate nucleus (ARC). Consistently, central glucagon significantly decreased AgRP expression. Inhibition of PKA and genetic activation of AMPK in the ARC blocked glucagon-induced anorexia in lean rats. Genetic down-regulation of glucagon receptors in the ARC stimulates fasting-induced hyperphagia. Although glucagon was unable to decrease food intake in DIO rats, glucagon sensitivity was restored after inactivation of CaMKKβ, specifically in the ARC. Thus, glucagon decreases food intake acutely via PKA/CaMKKβ/AMPK dependent pathways in the ARC, and CaMKKβ mediates its obesity-induced hypothalamic resistance. Conclusions This work reveals the molecular underpinnings by which glucagon controls feeding that may lead to a better understanding of disease states linked to anorexia and cachexia. PMID:26909312

  1. Hibiscus sabdariffa calyx palliates insulin resistance, hyperglycemia, dyslipidemia and oxidative rout in fructose-induced metabolic syndrome rats.

    Science.gov (United States)

    Ajiboye, Taofeek O; Raji, Hikmat O; Adeleye, Abdulwasiu O; Adigun, Nurudeen S; Giwa, Oluwayemisi B; Ojewuyi, Oluwayemisi B; Oladiji, Adenike T

    2016-03-30

    The effect of Hibiscus sabdariffa calyx extract was evaluated in high-fructose-induced metabolic syndrome rats. Insulin resistance, hyperglycemia, dyslipidemia and oxidative rout were induced in rats using high-fructose diet. High-fructose diet-fed rats were administered 100 and 200 mg kg(-1) body weight of H. sabdariffa extract for 3 weeks, starting from week 7 of high-fructose diet treatment. High-fructose diet significantly (P Hibiscus extract. Overall, aqueous extract of H. sabdariffa palliates insulin resistance, hyperglycemia, dyslipidemia and oxidative rout in high-fructose-induced metabolic syndrome rats. © 2015 Society of Chemical Industry.

  2. Differential effectiveness of Serratia plymuthica IC1270-induced systemic resistance against hemibiotrophic and necrotrophic leaf pathogens in rice

    Directory of Open Access Journals (Sweden)

    Höfte Monica M

    2009-01-01

    Full Text Available Abstract Background Induced resistance is a state of enhanced defensive capacity developed by a plant reacting to specific biotic or chemical stimuli. Over the years, several forms of induced resistance have been characterized, including systemic acquired resistance, which is induced upon localized infection by an avirulent necrotizing pathogen, and induced systemic resistance (ISR, which is elicited by selected strains of nonpathogenic rhizobacteria. However, contrary to the relative wealth of information on inducible defense responses in dicotyledoneous plants, our understanding of the molecular mechanisms underlying induced resistance phenomena in cereal crops is still in its infancy. Using a combined cytomolecular and pharmacological approach, we analyzed the host defense mechanisms associated with the establishment of ISR in rice by the rhizobacterium Serratia plymuthica IC1270. Results In a standardized soil-based assay, root treatment with IC1270 rendered foliar tissues more resistant to the hemibiotrophic pathogen Magnaporthe oryzae, causal agent of the devastating rice blast disease. Analysis of the cytological and biochemical alterations associated with restriction of fungal growth in IC1270-induced plants revealed that IC1270 primes rice for enhanced attacker-induced accumulation of reactive oxygen species (ROS and autofluorescent phenolic compounds in and near epidermal cells displaying dense cytoplasmic granulation. Similar, yet more abundant, phenotypes of hypersensitively dying cells in the vicinity of fungal hyphae were evident in a gene-for-gene interaction with an avirulent M. oryzae strain, suggesting that IC1270-inducible ISR and R protein conditioned effector-triggered immunity (ETI target similar defense mechanisms. Yet, this IC1270-inducible ISR response seems to act as a double-edged sword within the rice defense network as induced plants displayed an increased vulnerability to the necrotrophic pathogens Rhizoctonia

  3. Schedule-dependent interaction of paclitaxel (taxol[reg]) and irradiation in vitro

    International Nuclear Information System (INIS)

    Plasswilm, Ludwig; Cordes, Nils

    1996-01-01

    /ethanol: 90%). No significant difference between concentrations varied from 2 to 50 nmol was observed. Single dose irradiation (1x10Gy) leads to clonogenic survival of 5%. Single dose paclitaxel (1x10nmol) plus single dose irradiation (1x10Gy) lead to clonogenic survival of 9% (cremophor/ethanol: 11%). Fractionated radiation (2 Gy/d, day 1-5) shows an average clonogenic survival of 41%. Fractionated Taxol[reg] treatment (2 nmol/d, day 1-5) leads to an average clonogenic survival of 57% (cremophor/ethanol: 58%). The combination of fractionated Taxol[reg] administration (2 nmol/day, day 1 to day 5) plus fractionated irradiation (2 Gy/day, day 1 to day 5) leads to an average clonogenic survival of 12% (cremophor/ethanol: 23%). Thus, the data of fractionated treatment schedule demonstrate an enhancement ratio of 2.0 compared to single dose schedule. No significant difference of a 1-hour or 9-hour interval between Taxol[reg] administration and irradiation was detected. Flow cytometric measurements did not indicate any significant alterations in cell cycle DNA distribution. Conclusion: The data demonstrate a potential beneficial effect by combining fractionated Taxol[reg] administration with fractionated irradiation without evidence for G 2 /M arrest in DNA analysis. In contrast, an antagonistic effect was observed with single dose administration of Taxol[reg] 1-hour or 9-hours delivered before irradiation. The detailed mechanism of this different paclitaxel-induced interaction is not clear. There was a remarkable cytotoxicity after the administration of the solvent cremophor/ethanol alone

  4. Sensitivity to ionizing radiation and chemotherapeutic agents in gemcitabine-resistant human tumor cell lines

    NARCIS (Netherlands)

    van Bree, Chris; Castro Kreder, Natasja; Loves, Willem J. P.; Franken, Nicolaas A. P.; Peters, Godefridus J.; Haveman, Jaap

    2002-01-01

    Purpose: To determine cross-resistance to anti-tumor treatments in 2',2'difluorodeoxycytidine (dFdC, gemcitabine)-resistant human tumor cells. Methods and Materials: Human lung carcinoma cells SW-1573 (SWp) were made resistant to dFdC (SWg). Sensitivity to cisplatin (cDDP), paclitaxel,

  5. Coffee induces breast cancer resistance protein expression in Caco-2 cells.

    Science.gov (United States)

    Isshiki, Marina; Umezawa, Kazuo; Tamura, Hiroomi

    2011-01-01

    Coffee is a beverage that is consumed world-wide on a daily basis and is known to induce a series of metabolic and pharmacological effects, especially in the digestive tract. However, little is known concerning the effects of coffee on transporters in the gastrointestinal tract. To elucidate the effect of coffee on intestinal transporters, we investigated its effect on expression of the breast cancer resistance protein (BCRP/ABCG2) in a human colorectal cancer cell line, Caco-2. Coffee induced BCRP gene expression in Caco-2 cells in a coffee-dose dependent manner. Coffee treatment of Caco-2 cells also increased the level of BCRP protein, which corresponded to induction of gene expression, and also increased cellular efflux activity, as judged by Hoechst33342 accumulation. None of the major constituents of coffee tested could induce BCRP gene expression. The constituent of coffee that mediated this induction was extractable with ethyl acetate and was produced during the roasting process. Dehydromethylepoxyquinomicin (DHMEQ), an inhibitor of nuclear factor (NF)-κB, inhibited coffee-mediated induction of BCRP gene expression, suggesting involvement of NF-κB in this induction. Our data suggest that daily consumption of coffee might induce BCRP expression in the gastrointestinal tract and may affect the bioavailability of BCRP substrates.

  6. The Efficacy of Dandelion Root Extract in Inducing Apoptosis in Drug-Resistant Human Melanoma Cells

    Directory of Open Access Journals (Sweden)

    S. J. Chatterjee

    2011-01-01

    Full Text Available Notoriously chemoresistant melanoma has become the most prevalent form of cancer for the 25–29 North American age demographic. Standard treatment after early detection involves surgical excision (recurrence is possible, and metastatic melanoma is refractory to immuno-, radio-, and most harmful chemotherapies. Various natural compounds have shown efficacy in killing different cancers, albeit not always specifically. In this study, we show that dandelion root extract (DRE specifically and effectively induces apoptosis in human melanoma cells without inducing toxicity in noncancerous cells. Characteristic apoptotic morphology of nuclear condensation and phosphatidylserine flipping to the outer leaflet of the plasma membrane of A375 human melanoma cells was observed within 48 hours. DRE-induced apoptosis activates caspase-8 in A375 cells early on, demonstrating employment of an extrinsic apoptotic pathway to kill A375 cells. Reactive Oxygen Species (ROS generated from DRE-treated isolated mitochondria indicates that natural compounds in DRE can also directly target mitochondria. Interestingly, the relatively resistant G361 human melanoma cell line responded to DRE when combined with the metabolism interfering antitype II diabetic drug metformin. Therefore, treatment with this common, yet potent extract of natural compounds has proven novel in specifically inducing apoptosis in chemoresistant melanoma, without toxicity to healthy cells.

  7. Cdk2-Null Mice Are Resistant to ErbB-2-Induced Mammary Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Dipankar Ray

    2011-05-01

    Full Text Available The concept of targeting G1 cyclin-dependent kinases (CDKs in breast cancer treatments is supported by the fact that the genetic ablation of Cdk4 had minimal impacts on normal cell proliferation in majority of cell types, resulting in near-normal mouse development, whereas such loss of Cdk4 completely abrogated ErbB-2/neu-induced mammary tumorigenesis in mice. In most human breast cancer tissues, another G1-regulatory CDK, CDK2, is also hyperactivated by various mechanisms and is believed to be an important therapeutic target. In this report, we provide genetic evidence that CDK2 is essential for proliferation and oncogenesis of murine mammary epithelial cells. We observed that 87% of Cdk2-null mice were protected from ErbB-2-induced mammary tumorigenesis. Mouse embryonic fibroblasts isolated from Cdk2-null mouse showed resistance to various oncogene-induced transformation. Previously, we have reported that hemizygous loss of Cdc25A, the major activator of CDK2, can also protect mice from ErbB-2-induced mammary tumorigenesis [Cancer Res (2007 67(14: 6605–11]. Thus, we propose that CDC25A-CDK2 pathway is critical for the oncogenic action of ErbB-2 in mammary epithelial cells, in a manner similar to Cyclin D1/CDK4 pathway.

  8. Curcumin reverses the depressive-like behavior and insulin resistance induced by chronic mild stress.

    Science.gov (United States)

    Shen, Ji-Duo; Wei, Yu; Li, Yu-Jie; Qiao, Jing-Yi; Li, Yu-Cheng

    2017-08-01

    Increasing evidence has demonstrated that patients with depression have a higher risk of developing type 2 diabetes. Insulin resistance has been identified as the key mechanism linking depression and diabetes. The present study established a rat model of depression complicated by insulin resistance using a 12-week exposure to chronic mild stress (CMS) and investigated the therapeutic effects of curcumin. Sucrose intake tests were used to evaluate depressive-like behaviors, and oral glucose tolerance tests (OGTT) and intraperitoneal insulin tolerance tests (IPITT) were performed to evaluate insulin sensitivity. Serum parameters were detected using commercial kits. Real-time quantitative PCR was used to examine mRNA expression. CMS rats exhibited reduced sucrose consumption, increased serum glucose, insulin, triglyceride (TG), low density lipoprotein-cholesterol (LDL-C), non-esterified fatty acid (NEFA), glucagon, leptin, and corticosterone levels, as well as impaired insulin sensitivity. Curcumin upregulated the phosphorylation of insulin receptor substrate (IRS)-1 and protein kinase B (Akt) in the liver, enhanced insulin sensitivity, and reversed the metabolic abnormalities and depressive-like behaviors mentioned above. Moreover, curcumin increased the hepatic glycogen content by inhibiting glycogen synthase kinase (GSK)-3β and prevented gluconeogenesis by inhibiting phosphoenolpyruvate carboxykinase (PEPCK) and glucose 6-phosphatase (G6Pase). These results suggest that curcumin not only exerted antidepressant-like effects, but also reversed the insulin resistance and metabolic abnormalities induced by CMS. These data may provide evidence to support the potential use of curcumin against depression and/or metabolic disorders.

  9. Imipenem Treatment Induces Expression of Important Genes and Phenotypes in a Resistant Acinetobacter baumannii Isolate.

    Science.gov (United States)

    Dhabaan, Ghulam Nasser; AbuBakar, Sazaly; Cerqueira, Gustavo Maia; Al-Haroni, Mohammed; Pang, Sui Ping; Hassan, Hamimah

    2015-12-14

    Acinetobacter baumannii has emerged as a notorious multidrug-resistant pathogen, and development of novel control measures is of the utmost importance. Understanding the factors that play a role in drug resistance may contribute to the identification of novel therapeutic targets. Pili are essential for A. baumannii adherence to and biofilm formation on abiotic surfaces as well as virulence. In the present study, we found that biofilm formation was significantly induced in an imipenem-resistant (Imp(r)) strain treated with a subinhibitory concentration of antibiotic compared to that in an untreated control and an imipenem-susceptible (Imp(s)) isolate. Using microarray and quantitative PCR analyses, we observed that several genes responsible for the synthesis of type IV pili were significantly upregulated in the Imp(r) but not in the Imp(s) isolate. Notably, this finding is corroborated by an increase in the motility of the Imp(r) strain. Our results suggest that the ability to overproduce colonization factors in response to imipenem treatment confers biological advantage to A. baumannii and may contribute to clinical success. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  10. Resistance to reinfection in rats induced by irradiated metacercariae of Clonorchis sinensis

    Directory of Open Access Journals (Sweden)

    Fu Shi Quan

    2005-08-01

    Full Text Available A study was made to observe the association between the resistance to reinfection induced by irradiated metacercariae (MC of Clonorchis sinensis and antigen specific Th1- and Th2-type cytokine productions in rats. Rats were infected with 20 MC of C. sinensis, previously exposed to a single dose of gamma irradiation, which varied from 0 to 100 Gy. All of them, single dose of 12 Gy showed higher IgG antibody titer with lowest worm recovery. Thus, 50 MC were used to challenge infection in rats previously infected with 20 MC irradiated at 12 Gy and the highest resistance to challenge infection was observed. The results of lymphocyte proliferation with specific antigen, ES Ag were shown no difference of proliferative responses as compared with primary and challenge infection at 12 Gy irradiation dose. In the case of cytokines production were observed that interferon (IFN-gamma and interlukin (IL-2 were significantly enhanced, while IL-4 and IL-10 was almost unchanged to make comparison between primary and secondary infection at 12 Gy irradiation dose. In conclusion, the single dose of 12 Gy could be adopted for induction of the highest resistance to challenge infection. Up-regulation of Th1 type cytokines, IFN-gamma and IL-2 may be affected to develop vaccine by irradiated MC.

  11. Neratinib Plus Paclitaxel vs Trastuzumab Plus Paclitaxel in Previously Untreated Metastatic ERBB2-Positive Breast Cancer: The NEfERT-T Randomized Clinical Trial.

    Science.gov (United States)

    Awada, Ahmad; Colomer, Ramon; Inoue, Kenichi; Bondarenko, Igor; Badwe, Rajendra A; Demetriou, Georgia; Lee, Soo-Chin; Mehta, Ajay O; Kim, Sung-Bae; Bachelot, Thomas; Goswami, Chanchal; Deo, Suryanarayan; Bose, Ron; Wong, Alvin; Xu, Feng; Yao, Bin; Bryce, Richard; Carey, Lisa A

    2016-12-01

    Efficacious ERBB2 (formerly HER2 or HER2/neu)-directed treatments, in addition to trastuzumab and lapatinib, are needed. To determine whether neratinib, an irreversible pan-ERBB tyrosine kinase inhibitor, plus paclitaxel improves progression-free survival compared with trastuzumab plus paclitaxel in the first-line treatment of recurrent and/or metastatic ERBB2-positive breast cancer. In the randomized, controlled, open-label NEfERT-T trial conducted from August 2009 to December 2014 at 188 centers in 34 countries in Europe, Asia, Africa, and North America, 479 women with previously untreated recurrent and/or metastatic ERBB2-positive breast cancer were randomized to 1 of 2 treatment arms (neratinib-paclitaxel [n = 242] or trastuzumab-paclitaxel [n = 237]). Women with asymptomatic central nervous system metastases were eligible, and randomization was stratified by prior trastuzumab and lapatinib exposure, hormone-receptor status, and region. Women received neratinib (240 mg/d orally) or trastuzumab (4 mg/kg then 2 mg/kg weekly), each combined with paclitaxel (80 mg/m2 on days 1, 8, and 15 every 28 days). Primary prophylaxis for diarrhea was not mandatory. The primary outcome was progression-free survival. Secondary end points were response rate, clinical benefit rate, duration of response, frequency, and time to symptomatic and/or progressive central nervous system lesions, and safety. The intent-to-treat population comprised 479 women 18 years or older (neratinib-paclitaxel, n = 242; trastuzumab-paclitaxel, n = 237) randomized and stratified in their respective treatment arms by prior trastuzumab and lapatinib exposure, hormone-receptor status, and region. Median progression-free survival was 12.9 months (95% CI, 11.1-14.9) with neratinib-paclitaxel and 12.9 months (95% CI, 11.1-14.8) with trastuzumab-paclitaxel (hazard ratio [HR], 1.02; 95% CI, 0.81-1.27; P =.89). With neratinib-paclitaxel, the incidence of central nervous system recurrences was

  12. Biocontrol agent Bacillus amyloliquefaciens LJ02 induces systemic resistance against cucurbits powdery mildew.

    Science.gov (United States)

    Li, Yunlong; Gu, Yilin; Li, Juan; Xu, Mingzhu; Wei, Qing; Wang, Yuanhong

    2015-01-01

    Powdery mildew is a fungal disease found in a wide range of plants and can significantly reduce crop yields. Bacterial strain LJ02 is a biocontrol agent (BCA) isolated from a greenhouse in Tianjin, China. In combination of morphological, physiological, biochemical and phylogenetic analyses, strain LJ02 was classified as a new member of Bacillus amyloliquefaciens. Greenhouse trials showed that LJ02 fermentation broth (LJ02FB) can effectively diminish the occurrence of cucurbits powdery mildew. When treated with LJ02FB, cucumber seedlings produced significantly elevated production of superoxide dismutase, peroxidase, polyphenol oxidase and phenylalanine ammonia lyase as compared to that of the control. We further confirmed that the production of free salicylic acid (SA) and expression of one pathogenesis-related (PR) gene PR-1 in cucumber leaves were markedly elevated after treating with LJ02FB, suggesting that SA-mediated defense response was stimulated. Moreover, LJ02FB-treated cucumber leaves could secrete resistance-related substances into rhizosphere that inhibit the germination of fungi spores and the growth of pathogens. Finally, we separated bacterium and its fermented substances to test their respective effects and found that both components have SA-inducing activity and bacterium plays major roles. Altogether, we identified a BCA against powdery mildew and its mode of action by inducing systemic resistance such as SA signaling pathway.

  13. Induced systemic resistance against Botrytis cinerea by Micromonospora strains isolated from root nodules

    Directory of Open Access Journals (Sweden)

    Pilar eMartínez-Hidalgo

    2015-09-01

    Full Text Available Micromonospora is a Gram positive bacterium that can be isolated from nitrogen fixing nodules from healthy leguminous plants, where they could be beneficial to the plant. Their plant growth promoting activity in legume and non-legume plants has been previously demonstrated. The present study explores the ability of Micromonospora strains to control fungal pathogens and to stimulate plant immunity. Micromonospora strains isolated from surface sterilized nodules of alfalfa showed in vitro antifungal activity against several pathogenic fungi. Moreover, root inoculation of tomato plants with these Micromonospora strains effectively reduced leaf infection by the fungal pathogen Botrytis cinerea, despite spatial separation between both microorganisms. This induced systemic resistance, confirmed in different tomato cultivars, is long lasting. Gene expression analyses evidenced that Micromonospora stimulates the plant capacity to activate defense mechanisms upon pathogen attack. The defensive response of tomato plants inoculated with Micromonospora spp. differs from that of non-inoculated plants, showing a stronger induction of jasmonate-regulated defenses when the plant is challenged with a pathogen. The hypothesis of jasmonates playing a key role in this defense priming effect was confirmed using defense-impaired tomato mutants, since the JA-deficient line def1 was unable to display a long term induced resistance upon Micromonospora spp. inoculation.In conclusion, nodule isolated Micromonospora strains should be considered excellent candidates as biocontrol agents as they combine both direct antifungal activity against plant pathogens and the ability to prime plant immunity.

  14. Electric-field-induced extremely large change in resistance in graphene ferromagnets

    Science.gov (United States)

    Song, Yu

    2018-01-01

    A colossal magnetoresistance (˜100×10^3% ) and an extremely large magnetoresistance (˜1×10^6% ) have been previously explored in manganite perovskites and Dirac materials, respectively. However, the requirement of an extremely strong magnetic field (and an extremely low temperature) makes them not applicable for realistic devices. In this work, we propose a device that can generate even larger changes in resistance in a zero-magnetic field and at a high temperature. The device is composed of graphene under two strips of yttrium iron garnet (YIG), where two gate voltages are applied to cancel the heavy charge doping in the YIG-induced half-metallic ferromagnets. By calculations using the Landauer-Büttiker formalism, we demonstrate that, when a proper gate voltage is applied on the free ferromagnet, changes in resistance up to 305×10^6% (16×10^3% ) can be achieved at the liquid helium (nitrogen) temperature and in a zero magnetic field. We attribute such a remarkable effect to a gate-induced full-polarization reversal in the free ferromagnet, which results in a metal-state to insulator-state transition in the device. We also find that the proposed effect can be realized in devices using other magnetic insulators, such as EuO and EuS. Our work should be helpful for developing a realistic switching device that is energy saving and CMOS-technology compatible.

  15. Resistance training controls arterial blood pressure in rats with L-NAME- induced hypertension.

    Science.gov (United States)

    Araujo, Ayslan Jorge Santos de; Santos, Anne Carolline Veríssimo dos; Souza, Karine dos Santos; Aires, Marlúcia Bastos; Santana-Filho, Valter Joviniano; Fioretto, Emerson Ticona; Mota, Marcelo Mendonça; Santos, Márcio Roberto Viana

    2013-04-01

    Arterial hypertension is a multifactorial chronic condition caused by either congenital or acquired factors. To evaluate the effects of Resistance Training (RT) on arterial pressure, and on vascular reactivity and morphology, of L-NAME-treated hypertensive rats. Male Wistar rats (200 - 250 g) were allocated into Sedentary Normotensive (SN), Sedentary Hypertensive (SH) and Trained Hypertensive (TH) groups. Hypertension was induced by adding L-NAME (40 mg/Kg) to the drinking water for four weeks. Arterial pressure was evaluated before and after RT. RT was performed using 50% of 1RM, 3 sets of 10 repetitions, 3 times per week for four weeks. Vascular reactivity was measured in rat mesenteric artery rings by concentration-response curves to sodium nitroprusside (SNP); phenylephrine (PHE) was also used for histological and stereological analysis. Resistance training inhibited the increase in mean and diastolic arterial pressures. Significant reduction was observed in Rmax (maximal response) and pD2 (potency) of PHE between SH and TH groups. Arteries demonstrated normal intima, media and adventitia layers in all groups. Stereological analysis demonstrated no significant difference in luminal, tunica media, and total areas of arteries in the SH and TH groups when compared to the SN group. Wall-to-lumen ratio of SH arteries was significantly different compared to SN arteries (parteries. RT was able to prevent an increase in blood pressure under the conditions in this study. This appears to involve a vasoconstrictor regulation mechanism and maintenance of luminal diameter in L-NAME induced hypertensive rats.

  16. Biodistribution imaging of a paclitaxel-hyaluronan bioconjugate

    Energy Technology Data Exchange (ETDEWEB)

    Banzato, Alessandra; Rondina, Maria [Department of Oncology and Surgical Sciences, University of Padua, I-35128 Padova (Italy); Melendez-Alafort, Laura; Zangoni, Elena; Nadali, Anna [Department of Pharmaceutical Sciences, University of Padua, Padova (Italy); Renier, Davide [Fidia Farmaceutici, Abano Terme (Italy); Moschini, Giuliano [Department of Physics, University of Padua, Padova (Italy); Mazzi, Ulderico [Department of Pharmaceutical Sciences, University of Padua, Padova (Italy); Zanovello, Paola [Department of Oncology and Surgical Sciences, University of Padua, I-35128 Padova (Italy); Istituto Oncologico Veneto, IOV-IRCCS, Padova (Italy); Rosato, Antonio [Department of Oncology and Surgical Sciences, University of Padua, I-35128 Padova (Italy); Istituto Oncologico Veneto, IOV-IRCCS, Padova (Italy)], E-mail: antonio.rosato@unipd.it

    2009-07-15

    Introduction: Gamma-ray detectors represent sensitive and noninvasive instruments to evaluate in vivo the metabolic trapping of radiopharmaceuticals. This study aimed to assess the imaging biodistribution of a [{sup 99m}Tc]-radiolabelled new prototype bioconjugate composed of paclitaxel linked to hyaluronan (ONCOFID-P). Methods: A small gamma camera providing high-resolution images was employed. Imaging of biodistribution following intravenous, intraperitoneal, intravesical and oral administration was carried out for a 2-h period in anesthetized mice receiving [{sup 99m}Tc]ONCOFID-P. At the end of the observation time, radioactivity in organs was directly measured. As a control, groups of mice were treated with free [{sup 3}H]paclitaxel given according to the same administration routes, and organ biodistribution of the drug was assessed after 2 h. Results: Intravenous inoculation of [{sup 99m}Tc]ONCOFID-P was followed by a rapid and strong liver uptake. In fact, almost 80% of the imaging signal was detected in this organ 10 min after injection and such value remained constant thereafter, thus indicating that the bioconjugate given through the intravenous route could be well suited to targeting primary or metastatic liver neoplasias. Imaging of the bladder, abdomen and gastrointestinal tract after local administration disclosed that the radiolabelled compound remained confined to the cavities, suggesting a potential regional application for transitional bladder cell carcinomas, ovarian cancers and gastric tumors, respectively. Free [{sup 3}H]paclitaxel biodistribution profoundly differed from that of [{sup 99m}Tc]ONCOFID-P. Conclusions: Conjugation of drugs with polymers results in new chemical entities characterized by a modified biodistribution pattern. Therefore, preclinical studies based on imaging analysis of such new compounds can suggest novel therapeutic applications.

  17. PGBR extract ameliorates TNF-α induced insulin resistance in hepatocytes

    Directory of Open Access Journals (Sweden)

    Fu-Chih Chen

    2018-01-01

    Full Text Available Pre-germinated brown rice (PGBR could ameliorate metabolic syndrome, however, not much research estimates the effect of PGBR extract on insulin resistance. The aim of this study is to examine the effects of PGBR extract in TNF-α induced insulin resistance. HepG2 cells, hepatocytes, were cultured in DMEM medium and added with 5 μM insulin or with insulin and 30 ng/ml TNF-α or with insulin, TNF-α and PGBR extract (50, 100, 300 μg/ml. The glucose levels of the medium were decreased by insulin, demonstrating insulin promoted glucose uptake into cell. However, TNF-α inhibited glucose uptake into cells treated with insulin. Moreover, insulin increased the protein expressions of AMP-activated protein kinase (AMPK, insulin receptor substrate-1 (IRS-1, phosphatidylinositol-3-kinase-α (PI3K-α, serine/threonine kinase PI3K-linked protein kinase B (Akt/PKB, glucose transporter-2 (GLUT-2, glucokinase (GCK, peroxisome proliferator activated receptor-α (PPAR-α and PPAR-γ. TNF-α activated p65 and MAPKs (JNK1/2 and ERK1/2 which worsened the expressions of AMPK, IRS-1, PI3K-α, Akt/PKB, GLUT-2, GCK, glycogen synthase kinase-3 (GSK-3, PPAR-α and PPAR-γ. Once this relationship was established, we added PGBR extract to cell with insulin and TNF-α. We found glucose levels of medium were lowered and that the protein expressions of AMPK, IRS-1, PI3K-α, Akt/PKB, GLUT-2, GCK, GSK-3, PPAR-α, PPAR-γ and p65, JNK1/2 were also recovered. In conclusion, this study found that TNF-α inhibited insulin stimulated glucose uptake and aggravated related proteins expressions, suggesting that it might cause insulin resistance. PGBR extract was found to ameliorate this TNF-α induced insulin resistance, suggesting that it might be used in the future to help control insulin resistance.

  18. Excel-Based Tool for Pharmacokinetically Guided Dose Adjustment of Paclitaxel.

    Science.gov (United States)

    Kraff, Stefanie; Lindauer, Andreas; Joerger, Markus; Salamone, Salvatore J; Jaehde, Ulrich

    2015-12-01

    Neutropenia is a frequent and severe adverse event in patients receiving paclitaxel chemotherapy. The time above a paclitaxel threshold concentration of 0.05 μmol/L (Tc > 0.05 μmol/L) is a strong predictor for paclitaxel-associated neutropenia and has been proposed as a target pharmacokinetic (PK) parameter for paclitaxel therapeutic drug monitoring and dose adaptation. Up to now, individual Tc > 0.05 μmol/L values are estimated based on a published PK model of paclitaxel by using the software NONMEM. Because many clinicians are not familiar with the use of NONMEM, an Excel-based dosing tool was developed to allow calculation of paclitaxel Tc > 0.05 μmol/L and give clinicians an easy-to-use tool. Population PK parameters of paclitaxel were taken from a published PK model. An Alglib VBA code was implemented in Excel 2007 to compute differential equations for the paclitaxel PK model. Maximum a posteriori Bayesian estimates of the PK parameters were determined with the Excel Solver using individual drug concentrations. Concentrations from 250 patients were simulated receiving 1 cycle of paclitaxel chemotherapy. Predictions of paclitaxel Tc > 0.05 μmol/L as calculated by the Excel tool were compared with NONMEM, whereby maximum a posteriori Bayesian estimates were obtained using the POSTHOC function. There was a good concordance and comparable predictive performance between Excel and NONMEM regarding predicted paclitaxel plasma concentrations and Tc > 0.05 μmol/L values. Tc > 0.05 μmol/L had a maximum bias of 3% and an error on precision of 0.05 μmol/L values between both programs was 1%. The Excel-based tool can estimate the time above a paclitaxel threshold concentration of 0.05 μmol/L with acceptable accuracy and precision. The presented Excel tool allows reliable calculation of paclitaxel Tc > 0.05 μmol/L and thus allows target concentration intervention to improve the benefit-risk ratio of the drug. The easy use facilitates therapeutic drug monitoring in

  19. Deciphering the hormonal signalling network behind the systemic resistance induced by Trichoderma harzianum in tomato

    Directory of Open Access Journals (Sweden)

    Ainhoa eMartinez-Medina

    2013-06-01

    Full Text Available Root colonization by selected Trichoderma isolates can activate in the plant a systemic defence response that is effective against a broad spectrum of plant pathogens. Diverse plant hormones play pivotal roles in the regulation of the defence signalling network that leads to the induction of systemic resistance triggered by beneficial organisms (ISR. Among them, jasmonic acid (JA and ethylene (ET signalling pathways are generally essential for ISR. However, Trichoderma ISR (TISR is believed to involve a wider variety of signalling routes, interconnected in a complex network of cross-communicating hormone pathways. Using tomato as a model, an integrative analysis of the main mechanisms involved in the systemic resistance induced by Trichoderma harzianum against the necrotrophic leaf pathogen Botrytis cinerea was performed. Root colonization by T. harzianum rendered the leaves more resistant to B. cinerea independently of major effects on plant nutrition. The analysis of disease development in shoots of tomato mutant lines impaired in the synthesis of the key defence related hormones JA, ET, salicylic acid (SA and abscisic acid (ABA and the peptide prosystemin (PS evidenced the requirement of intact JA, SA and ABA signalling pathways for a functional TISR. Expression analysis of several hormone related marker genes point to the role of priming for enhanced JA-dependent defence responses upon pathogen infection. Together, our results indicate that although TISR induced in tomato against the necrotrophs is mainly based on boosted JA-dependent responses, the pathways regulated by the plant hormones SA- and ABA are also required for successful TISR development

  20. Impact of Microbiota on Resistance to Ocular Pseudomonas aeruginosa-Induced Keratitis.

    Directory of Open Access Journals (Sweden)

    Abirami Kugadas

    2016-09-01

    Full Text Available The existence of the ocular microbiota has been reported but functional analyses to evaluate its significance in regulating ocular immunity are currently lacking. We compared the relative contribution of eye and gut commensals in regulating the ocular susceptibility to Pseudomonas aeruginosa-induced keratitis. We find that in health, the presence of microbiota strengthened the ocular innate immune barrier by significantly increasing the concentrations of immune effectors in the tear film, including secretory IgA and complement proteins. Consistent with this view, Swiss Webster (SW mice that are typically resistant to P. aeruginosa-induced keratitis become susceptible due to the lack of microbiota. This was exemplified by increased corneal bacterial burden and elevated pathology of the germ free (GF mice when compared to the conventionally maintained SW mice. The protective immunity was found to be dependent on both eye and gut microbiota with the eye microbiota having a moderate, but significant impact on the resistance to infection. These events were IL-1ß-dependent as corneal IL-1ß levels were decreased in the infected GF and antibiotic-treated mice when compared to the SPF controls, and neutralization of IL-1ß increased the ocular bacterial burden in the SPF mice. Monocolonizing GF mice with Coagulase Negative Staphylococcus sp. isolated from the conjunctival swabs was sufficient to restore resistance to infection. Cumulatively, these data underline a previously unappreciated role for microbiota in regulating susceptibility to ocular keratitis. We predict that these results will have significant implications for contact lens wearers, where alterations in the ocular commensal communities may render the ocular surface vulnerable to infections.

  1. A mucoadhesive in situ gel delivery system for paclitaxel

    OpenAIRE

    Jauhari, Saurabh; Dash, Alekha K.

    2006-01-01

    MUC1 gene encodes a transmembrane mucin glycoprotein that is overexpressed in human breast cancer and colon cancer. The objective of this study was to develop an in situ gel delivery system containing paclitaxel (PTX) and mucoadhesives for sustained and targeted delivery of anticancer drugs. The delivery system consisted of chitosan and glyceryl monooleate (GMO) in 0.33M citric acid containing PTX. The in vitro release of PTX from the gel was performed in presence and absence of Tween 80 at d...

  2. Microwave-assisted efficient conjugation of nanodiamond and paclitaxel.

    Science.gov (United States)

    Hsieh, Yi-Han; Liu, Kuang-Kai; Sulake, Rohidas S; Chao, Jui-I; Chen, Chinpiao

    2015-01-01

    Nanodiamond has recently received considerable attention due to the various possible applications in medical field such as drug delivery and bio-labeling. For this purpose suitable and effective surface functionalization of the diamond material are required. A versatile and reproducible surface modification method of nanoscale diamond is essential for functionalization. We introduce the input of microwave energy to assist the functionalization of nanodiamond surface. The feasibility of such a process is illustrated by comparing the biological assay of ND-paclitaxel synthesized by conventional and microwave irradiating. Using a microwave we manage to have approximately doubled grafted molecules per nanoparticle of nanodiamond. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Angiotensin II receptor blocker ameliorates stress-induced adipose tissue inflammation and insulin resistance.

    Directory of Open Access Journals (Sweden)

    Motoharu Hayashi

    Full Text Available A strong causal link exists between psychological stress and insulin resistance as well with hypertension. Meanwhile, stress-related responses play critical roles in glucose metabolism in hypertensive patients. As clinical trials suggest that angiotensin-receptor blocker delays the onset of diabetes in hypertensive patients, we investigated the effects of irbesartan on stress-induced adipose tissue inflammation and insulin resistance. C57BL/6J mice were subjected to 2-week intermittent restraint stress and orally treated with vehicle, 3 and 10 mg/kg/day irbesartan. The plasma concentrations of lipid and proinflammatory cytokines [Monocyte Chemoattractant Protein-1 (MCP-1, tumor necrosis factor-α, and interleukin-6] were assessed with enzyme-linked immunosorbent assay. Monocyte/macrophage accumulation in inguinal white adipose tissue (WAT was observed with CD11b-positive cell counts and mRNA expressions of CD68 and F4/80 using immunohistochemistry and RT-PCR methods respectively. The mRNA levels of angiotensinogen, proinflammatory cytokines shown above, and adiponectin in WAT were also assessed with RT-PCR method. Glucose metabolism was assessed by glucose tolerance tests (GTTs and insulin tolerance tests, and mRNA expression of insulin receptor substrate-1 (IRS-1 and glucose transporter 4 (GLUT4 in WAT. Restraint stress increased monocyte accumulation, plasma free fatty acids, expression of angiotensinogen and proinflammatory cytokines including MCP-1, and reduced adiponectin. Irbesartan reduced stress-induced monocyte accumulation in WAT in a dose dependent manner. Irbesartan treatment also suppressed induction of adipose angiotensinogen and proinflammatory cytokines in WAT and blood, and reversed changes in adiponectin expression. Notably, irbesartan suppressed stress-induced reduction in adipose tissue weight and free fatty acid release, and improved insulin tolerance with restoration of IRS-1 and GLUT4 mRNA expressions in WAT. The results

  4. Field Trials of the Multi-Source Approach for Resistivity and Induced Polarization Data Acquisition

    Science.gov (United States)

    LaBrecque, D. J.; Morelli, G.; Fischanger, F.; Lamoureux, P.; Brigham, R.

    2013-12-01

    Implementing systems of distributed receivers and transmitters for resistivity and induced polarization data is an almost inevitable result of the availability of wireless data communication modules and GPS modules offering precise timing and instrument locations. Such systems have a number of advantages; for example, they can be deployed around obstacles such as rivers, canyons, or mountains which would be difficult with traditional 'hard-wired' systems. However, deploying a system of identical, small, battery powered, transceivers, each capable of injecting a known current and measuring the induced potential has an additional and less obvious advantage in that multiple units can inject current simultaneously. The original purpose for using multiple simultaneous current sources (multi-source) was to increase signal levels. In traditional systems, to double the received signal you inject twice the current which requires you to apply twice the voltage and thus four times the power. Alternatively, one approach to increasing signal levels for large-scale surveys collected using small, battery powered transceivers is it to allow multiple units to transmit in parallel. In theory, using four 400 watt transmitters on separate, parallel dipoles yields roughly the same signal as a single 6400 watt transmitter. Furthermore, implementing the multi-source approach creates the opportunity to apply more complex current flow patterns than simple, parallel dipoles. For a perfect, noise-free system, multi-sources adds no new information to a data set that contains a comprehensive set of data collected using single sources. However, for realistic, noisy systems, it appears that multi-source data can substantially impact survey results. In preliminary model studies, the multi-source data produced such startling improvements in subsurface images that even the authors questioned their veracity. Between December of 2012 and July of 2013, we completed multi-source surveys at five sites

  5. Cell death induced by taxanes in breast cancer cells: cytochrome C is released in resistant but not in sensitive cells

    Czech Academy of Sciences Publication Activity Database

    Ehrlichová, Marie; Koc, Michal; Truksa, Jaroslav; Naďová, Zuzana; Václavíková, R.; Kovář, Jan

    2005-01-01

    Roč. 25, 6B (2005), s. 4215-4224 ISSN 0250-7005 R&D Projects: GA MZd(CZ) NL7567 Institutional research plan: CEZ:AV0Z50520514 Keywords : paclitaxel * cell death * breast cancer cells Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.604, year: 2005

  6. Bcl-2 silencing attenuates hypoxia-induced apoptosis resistance in pulmonary microvascular endothelial cells.

    Science.gov (United States)

    Cao, Yongmei; Jiang, Zhen; Zeng, Zhen; Liu, Yujing; Gu, Yuchun; Ji, Yingying; Zhao, Yupeng; Li, Yingchuan

    2016-01-01

    Pulmonary arterial hypertension (PAH) is a life-threatening disorder that ultimately causes heart failure. While the underlying causes of this condition are not well understood, previous studies suggest that the anti-apoptotic nature of pulmonary microvascular endothelial cells (PMVECs) in hypoxic environments contributes to PAH pathogenesis. In this study, we focus on the contribution of Bcl-2 and hypoxia response element (HRE) to apoptosis-resistant endothelial cells and investigate the mechanism. PMVECs obtained from either normal rats or apoptosis-resistant PMVECs obtained from PAH rats were transduced with recombinant lentiviral vectors carrying either Bcl-2-shRNA or HRE combined Bcl-2-shRNA, and then cultured these cells for 24 h under hypoxic (5% O2) or normoxic (21% O2) conditions. In normal PMVECs, Bcl-2-shRNA or HRE combined with Bcl-2-shRNA transduction successfully decreased Bcl-2 expression, while increasing apoptosis as well as caspase-3 and P53 expression in a normoxic environment. In a hypoxic environment, the effects of Bcl-2-shRNA treatment on cell apoptosis, and on Bcl-2, caspase-3, P53 expression were significantly suppressed. Conversely, HRE activation combined with Bcl-2-shRNA transduction markedly enhanced cell apoptosis and upregulated caspase-3 and P53 expression, while decreasing Bcl-2 expression. Furthermore, in apoptosis-resistant PMVECs, HRE-mediated Bcl-2 silencing effectively enhanced cell apoptosis and caspase-3 activity. The apoptosis rate was significantly depressed when Lv-HRE-Bcl-2-shRNA was combined with Lv-P53-shRNA or Lv-caspase3-shRNA transduction in a hypoxic environment. These results suggest that HRE-mediated Bcl-2 inhibition can effectively attenuate hypoxia-induced apoptosis resistance in PMVECs by downregulating Bcl-2 expression and upregulating caspase-3 and P53 expression. This study therefore reveals critical insight into potential therapeutic targets for treating PAH.

  7. New Real-Time PCR Assays for Detection of Inducible and Acquired Clarithromycin Resistance in the Mycobacterium abscessus Group.

    Science.gov (United States)

    Shallom, Shamira J; Moura, Natalia S; Olivier, Kenneth N; Sampaio, Elizabeth P; Holland, Steven M; Zelazny, Adrian M

    2015-11-01

    Members of the Mycobacterium abscessus group (MAG) cause lung, soft tissue, and disseminated infections. The oral macrolides clarithromycin and azithromycin are commonly used for treatment. MAG can display clarithromycin resistance through the inducible erm(41) gene or via acquired mutations in the rrl (23S rRNA) gene. Strains harboring a truncation or a T28C substitution in erm(41) lose the inducible resistance trait. Phenotypic detection of clarithromycin resistance requires extended incubation (14 days), highlighting the need for faster methods to detect resistance. Two real-time PCR-based assays were developed to assess inducible and acquired clarithromycin resistance and tested on a total of 90 clinical and reference strains. A SYBR green assay was designed to distinguish between a full-length and truncated erm(41) gene by temperature shift in melting curve analysis. Single nucleotide polymorphism (SNP) allele discrimination assays were developed to distinguish T or C at position 28 of erm(41) and 23S rRNA rrl gene mutations at position 2058 and/or 2059. Truncated and full-size erm(41) genes were detected in 21/90 and 69/90 strains, respectively, with 64/69 displaying T at nucleotide position 28 and 5/69 containing C at that position. Fifteen isolates showed rrl mutations conferring clarithromycin resistance, including A2058G (11 isolates), A2058C (3 isolates), and A2059G (1 isolate). Targeted sequencing and phenotypic assessment of resistance concurred with molecular assay results. Interestingly, we also noted cooccurring strains harboring an active erm(41), inactive erm(41), and/or acquired mutational resistance, as well as slowly growing MAG strains and also strains displaying an inducible resistance phenotype within 5 days, long before the recommended 14-day extended incubation. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  8. Modeling and inversion Matlab algorithms for resistivity, induced polarization and seismic data

    Science.gov (United States)

    Karaoulis, M.; Revil, A.; Minsley, B. J.; Werkema, D. D.

    2011-12-01

    M. Karaoulis (1), D.D. Werkema (3), A. Revil (1,2), A., B. Minsley (4), (1) Colorado School of Mines, Dept. of Geophysics, Golden, CO, USA. (2) ISTerre, CNRS, UMR 5559, Université de Savoie, Equipe Volcan, Le Bourget du Lac, France. (3) U.S. EPA, ORD, NERL, ESD, CMB, Las Vegas, Nevada, USA . (4) USGS, Federal Center, Lakewood, 10, 80225-0046, CO. Abstract We propose 2D and 3D forward modeling and inversion package for DC resistivity, time domain induced polarization (IP), frequency-domain IP, and seismic refraction data. For the resistivity and IP case, discretization is based on rectangular cells, where each cell has as unknown resistivity in the case of DC modelling, resistivity and chargeability in the time domain IP modelling, and complex resistivity in the spectral IP modelling. The governing partial-differential equations are solved with the finite element method, which can be applied to both real and complex variables that are solved for. For the seismic case, forward modeling is based on solving the eikonal equation using a second-order fast marching method. The wavepaths are materialized by Fresnel volumes rather than by conventional rays. This approach accounts for complicated velocity models and is advantageous because it considers frequency effects on the velocity resolution. The inversion can accommodate data at a single time step, or as a time-lapse dataset if the geophysical data are gathered for monitoring purposes. The aim of time-lapse inversion is to find the change in the velocities or resistivities of each model cell as a function of time. Different time-lapse algorithms can be applied such as independent inversion, difference inversion, 4D inversion, and 4D active time constraint inversion. The forward algorithms are benchmarked against analytical solutions and inversion results are compared with existing ones. The algorithms are packaged as Matlab codes with a simple Graphical User Interface. Although the code is parallelized for multi

  9. The involvement of topoisomerases and DNA polymerase I in the mechanism of induced thermal and radiation resistance in yeast

    International Nuclear Information System (INIS)

    Boreham, D.R.; Trivedi, A.; Weinberger, P.; Mitchel, R.E.

    1990-01-01

    Either an ionizing radiation exposure or a heat shock is capable of inducing both thermal tolerance and radiation resistance in yeast. Yeast mutants, deficient in topoisomerase I, in topoisomerase II, or in DNA polymerase I, were used to investigate the mechanism of these inducible resistances. The absence of either or both topoisomerase activities did not prevent induction of either heat or radiation resistance. However, if both topoisomerase I and II activities were absent, the sensitivity of yeast to become thermally tolerant (in response to a heat stress) was markedly increased. The absence of only topoisomerase I activity (top1) resulted in the constitutive expression of increased radiation resistance equivalent to that induced by a heat shock in wild-type cells, and the topoisomerase I-deficient cells were not further inducible by heat. This heat-inducible component of radiation resistance (or its equivalent constitutive expression in top1 cells) was, in turn, only a portion of the full response inducible by radiation. The absence of polymerase I activity had no detectable effect on either response. Our results indicate that the actual systems that confer resistance to heat or radiation are independent of either topoisomerase activity or DNA polymerase function, but suggest that topoisomerases may have a regulatory role during the signaling of these mechanisms. The results of our experiments imply that maintenance of correct DNA topology prevents induction of the heat-shock response, and that heat-shock induction of a component of the full radiation resistance in yeast may be the consequence of topoisomerase I inactivation

  10. Intrinsic mechanism of estradiol-induced apoptosis in breast cancer cells resistant to estrogen deprivation.

    Science.gov (United States)

    Lewis, Joan S; Meeke, Kathleen; Osipo, Clodia; Ross, Eric A; Kidawi, Noman; Li, Tianyu; Bell, Eric; Chandel, Navdeep S; Jordan, V Craig

    2005-12-07

    We previously developed an estrogen receptor (ER)-positive breast cancer cell line (MCF-7:5C) that is resistant to long-term estrogen deprivation and undergoes rapid and complete apoptosis in the presence of physiologic concentrations of 17beta-estradiol. Here, we investigated the role of the mitochondrial apoptotic pathway in this process. Apoptosis in MCF-7:5C cells treated with estradiol, fulvestrant, or vehicle (control) was investigated by annexin V-propidium iodide double staining and 4',6-diamidino-2-phenylindole (DAPI) staining. Apoptosis was also analyzed in MCF-7:5C cells transiently transfected with small interfering RNAs (siRNAs) to apoptotic pathway components. Expression of apoptotic pathway intermediates was measured by western blot analysis. Mitochondrial transmembrane potential (psim) was determined by rhodamine-123 retention assay. Mitochondrial pathway activity was determined by cytochrome c release and cleavage of poly(ADP-ribose) polymerase (PARP) protein. Tumorigenesis was studied in ovariectomized athymic mice that were injected with MCF-7:5C cells. Differences between the treatment groups and control group were determined by two-sample t test or one-factor analysis of variance. All statistical tests were two-sided. MCF-7:5C cells treated with estradiol underwent apoptosis and showed increased expression of proapoptotic proteins, decreased psim, enhanced cytochrome c release, and PARP cleavage compared with cells treated with fulvestrant or vehicle. Blockade of Bax, Bim, and p53 mRNA expression by siRNA reduced estradiol-induced apoptosis relative to control by 76% [95% confidence interval (CI) = 73% to 79%, P estradiol-induced apoptosis in long-term estrogen-deprived breast cancer cells. Physiologic concentrations of estradiol could potentially be used to induce apoptosis and tumor regression in tumors that have developed resistance to aromatase inhibitors.

  11. Development of New Lipid-Based Paclitaxel Nanoparticles Using Sequential Simplex Optimization

    Science.gov (United States)

    Dong, Xiaowei; Mattingly, Cynthia A.; Tseng, Michael; Cho, Moo; Adams, Val R.; Mumper, Russell J.

    2008-01-01

    The objective of these studies was to develop Cremophor-free lipid-based paclitaxel (PX) nanoparticle formulations prepared from warm microemulsion precursors. To identify and optimize new nanoparticles, experimental design was performed combining Taguchi array and sequential simplex optimization. The combination of Taguchi array and sequential simplex optimization efficiently directed the design of paclitaxel nanoparticles. Two optimized paclitaxel nanoparticles (NPs) were obtained: G78 NPs composed of glyceryl tridodecanoate (GT) and polyoxyethylene 20-stearyl ether (Brij 78), and BTM NPs composed of Miglyol 812, Brij 78 and D-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS). Both nanoparticles successfully entrapped paclitaxel at a final concentration of 150 μg/ml (over 6% drug loading) with particle sizes less than 200 nm and over 85% of entrapment efficiency. These novel paclitaxel nanoparticles were stable at 4°C over three months and in PBS at 37°C over 102 hours as measured by physical stability. Release of paclitaxel was slow and sustained without initial burst release. Cytotoxicity studies in MDA-MB-231 cancer cells showed that both nanoparticles have similar anticancer activities compared to Taxol®. Interestingly, PX BTM nanocapsules could be lyophilized without cryoprotectants. The lyophilized powder comprised only of PX BTM NPs in water could be rapidly rehydrated with complete retention of original physicochemical properties, in-vitro release properties, and cytotoxicity profile. Sequential Simplex Optimization has been utilized to identify promising new lipid-based paclitaxel nanoparticles having useful attributes. PMID:19111929

  12. Acoustically active lipospheres containing paclitaxel: a new therapeutic ultrasound contrast agent.

    Science.gov (United States)

    Unger, E C; McCreery, T P; Sweitzer, R H; Caldwell, V E; Wu, Y

    1998-12-01

    Paclitaxel-carrying lipospheres (MRX-552) were developed and evaluated as a new ultrasound contrast agent for chemotherapeutic drug delivery. Paclitaxel was suspended in soybean oil and added to an aqueous suspension of phospholipids in vials. The headspace of the vials was replaced with perfluorobutane gas; the vials were sealed, and they were agitated at 4200 rpm on a shaking device. The resulting lipospheres containing paclitaxel were studied for concentration, size, acute toxicity in mice, and acoustic activity and drug release with ultrasound. Lipospheres containing sudan black dye were produced to demonstrate the acoustically active liposphere (AAL)-ultrasound release concept. Acoustically active lipospheres containing paclitaxel had a mean particle count of approximately 1 x 10(9) particles per mL and a mean size of 2.9 microns. Acute toxicity studies in mice showed a 10-fold reduction in toxicity for paclitaxel in AALs compared with free paclitaxel. The AALs reflected ultrasound as a contrast agent. Increasing amounts of ultrasound energy selectively ruptured the AALs and released the paclitaxel. Acoustically active lipospheres represent a new class of acoustically active drug delivery vehicles. Future studies will assess efficacy of AALs for ultrasound-mediated drug delivery.

  13. MicroRNA-21 induces 5-fluorouracil resistance in human pancreatic cancer cells by regulating PTEN and PDCD4

    International Nuclear Information System (INIS)

    Wei, Xueju; Wang, Weibin; Wang, Lanlan; Zhang, Yuanyuan; Zhang, Xian; Chen, Mingtai; Wang, Fang; Yu, Jia; Ma, Yanni; Sun, Guotao

    2016-01-01

    Pancreatic cancer patients are often resistant to chemotherapy treatment, which results in poor prognosis. The objective of this study was to delineate the mechanism by which miR-21 induces drug resistance to 5-fluorouracil (5-FU) in human pancreatic cancer cells (PATU8988 and PANC-1). We report that PATU8988 cells resistant to 5-FU express high levels of miR-21 in comparison to sensitive primary PATU8988 cells. Suppression of miR-21 expression in 5-Fu-resistant PATU8988 cells can alleviate its 5-FU resistance. Meanwhile, lentiviral vector-mediated overexpression of miR-21 not only conferred resistance to 5-FU but also promoted proliferation, migration, and invasion of PATU8988 and PANC-1 cells. The proresistance effects of miR-21 were attributed to the attenuated expression of tumor suppressor genes, including PTEN and PDCD4. Overexpression of PTEN and PDCD4 antagonized miR-21-induced resistance to 5-FU and migration activity. Our work demonstrates that miR-21 can confer drug resistance to 5-FU in pancreatic cancer cells by regulating the expression of tumor suppressor genes, as the target genes of miR-21, PTEN and PDCD4 can rescue 5-FU sensitivity and the phenotypic characteristics disrupted by miR-21

  14. Zinc blocks SOS-induced antibiotic resistance via inhibition of RecA in Escherichia coli.

    Science.gov (United States)

    Bunnell, Bryan E; Escobar, Jillian F; Bair, Kirsten L; Sutton, Mark D; Crane, John K

    2017-01-01

    Zinc inhibits the virulence of diarrheagenic E. coli by inducing the envelope stress response and inhibiting the SOS response. The SOS response is triggered by damage to bacterial DNA. In Shiga-toxigenic E. coli, the SOS response strongly induces the production of Shiga toxins (Stx) and of the bacteriophages that encode the Stx genes. In E. coli, induction of the SOS response is accompanied by a higher mutation rate, called the mutator response, caused by a shift to error-prone DNA polymerases when DNA damage is too severe to be repaired by canonical DNA polymerases. Since zinc inhibited the other aspects of the SOS response, we hypothesized that zinc would also inhibit the mutator response, also known as hypermutation. We explored various different experimental paradigms to induce hypermutation triggered by the SOS response, and found that hypermutation was induced not just by classical inducers such as mitomycin C and the quinolone antibiotics, but also by antiviral drugs such as zidovudine and anti-cancer drugs such as 5-fluorouracil, 6-mercaptopurine, and azacytidine. Zinc salts inhibited the SOS response and the hypermutator phenomenon in E. coli as well as in Klebsiella pneumoniae, and was more effective in inhibiting the SOS response than other metals. We then attempted to determine the mechanism by which zinc, applied externally in the medium, inhibits hypermutation. Our results show that zinc interferes with the actions of RecA, and protects LexA from RecA-mediated cleavage, an early step in initiation of the SOS response. The SOS response may play a role in the development of antibiotic resistance and the effect of zinc suggests ways to prevent it.

  15. Zinc blocks SOS-induced antibiotic resistance via inhibition of RecA in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Bryan E Bunnell

    Full Text Available Zinc inhibits the virulence of diarrheagenic E. coli by inducing the envelope stress response and inhibiting the SOS response. The SOS response is triggered by damage to bacterial DNA. In Shiga-toxigenic E. coli, the SOS response strongly induces the production of Shiga toxins (Stx and of the bacteriophages that encode the Stx genes. In E. coli, induction of the SOS response is accompanied by a higher mutation rate, called the mutator response, caused by a shift to error-prone DNA polymerases when DNA damage is too severe to be repaired by canonical DNA polymerases. Since zinc inhibited the other aspects of the SOS response, we hypothesized that zinc would also inhibit the mutator response, also known as hypermutation. We explored various different experimental paradigms to induce hypermutation triggered by the SOS response, and found that hypermutation was induced not just by classical inducers such as mitomycin C and the quinolone antibiotics, but also by antiviral drugs such as zidovudine and anti-cancer drugs such as 5-fluorouracil, 6-mercaptopurine, and azacytidine. Zinc salts inhibited the SOS response and the hypermutator phenomenon in E. coli as well as in Klebsiella pneumoniae, and was more effective in inhibiting the SOS response than other metals. We then attempted to determine the mechanism by which zinc, applied externally in the medium, inhibits hypermutation. Our results show that zinc interferes with the actions of RecA, and protects LexA from RecA-mediated cleavage, an early step in initiation of the SOS response. The SOS response may play a role in the development of antibiotic resistance and the effect of zinc suggests ways to prevent it.

  16. Silymarin ameliorates fructose induced insulin resistance syndrome by reducing de novo hepatic lipogenesis in the rat.

    Science.gov (United States)

    Prakash, Prem; Singh, Vishal; Jain, Manish; Rana, Minakshi; Khanna, Vivek; Barthwal, Manoj Kumar; Dikshit, Madhu

    2014-03-15

    High dietary fructose causes insulin resistance syndrome (IRS), primarily due to simultaneous induction of genes involved in glucose, lipid and mitochondrial oxidative metabolism. The present study evaluates effect of a hepatoprotective agent, silymarin (SYM) on fructose-induced metabolic abnormalities in the rat and also assessed the associated thrombotic complications. Wistar rats were kept on high fructose (HFr) diet throughout the 12-week study duration (9 weeks of HFr feeding and subsequently 3 weeks of HFr plus SYM oral administration [once daily]). SYM treatment significantly reduced the HFr diet-induced increase expression of peroxisome proliferator-activated receptor gamma coactivator (PGC)-1α/β, peroxisome proliferator-activated receptor (PPAR)-α, forkhead box protein O1 (FOXO1), sterol regulatory element binding protein (SREBP)-1c, liver X receptor (LXR)-β, fatty acid synthase (FAS) and PPARγ genes in rat liver. SYM also reduced HFr diet mediated increase in plasma triglycerides (TG), non-esterified fatty acids (NEFA), uric acid, malondialdehyde (MDA), total nitrite and pro-inflammatory cytokines (C-reactive protein [CRP], interleukin-6 [IL-6], interferon-gamma [IFN-γ] and tumor necrosis factor [TNF]) levels. Moreover, SYM ameliorated HFr diet induced reduction in glucose utilization and endothelial dysfunction. Additionally, SYM significantly reduced platelet activation (adhesion and aggregation), prolonged ferric chloride-induced blood vessel occlusion time and protected against exacerbated myocardial ischemia reperfusion (MI-RP) injury. SYM treatment prevented HFr induced mRNA expression of hepatic PGC-1α/β and also its target transcription factors which was accompanied with recovery in insulin sensitivity and reduced propensity towards thrombotic complications and aggravated MI-RP injury. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. The Thrombospondin-1 Mimetic ABT-510 Increases the Uptake and Effectiveness of Cisplatin and Paclitaxel in a Mouse Model of Epithelial Ovarian Cancer

    Directory of Open Access Journals (Sweden)

    Nicole E. Campbell

    2010-03-01

    Full Text Available Epithelial ovarian cancer (EOC comprises approximately 90% of ovarian cancers and arises from the surface epithelium. Typical treatment of EOC involves cytoreductive surgery combined with chemotherapy. More recent therapies have targeted the tumor vasculature using antiangiogenic compounds such as thrombospondin-1 (TSP-1. TSP-1 mimetic peptides such as ABT-510 have been created and have been in various clinical trials. We have previously shown that ABT-510 reduces abnormal vasculature associated with tumor tissue and increases the presence of mature blood vessels. It has been hypothesized that treatment with antiangiogenic compounds would allow increased delivery of cytotoxic agents and enhance treatment. In this study, we evaluated the potential role of ABT-510 and various chemotherapeutics (cisplatin and paclitaxel on tumor progression, angiogenesis, and the benefits of combinational treatments on tissue uptake and perfusion using an orthotopic syngeneic mouse model of EOC. Animals were treated with ABT-510 (100 mg/kg per day alone or in combination with cisplatin (2 mg/kg per 3 days or paclitaxel (10 mg/kg per 2 days at 60 days after tumor induction. Radiolabeled and fluorescently labeled paclitaxel demonstrated a significant increase in tumor uptake after ABT-510 treatment. Combined treatment with ABT-510 and cisplatin or paclitaxel resulted in a significant increase in tumor cell and tumor endothelial cell apoptosis and a resultant decrease in ovarian tumor size. Combined treatment also regressed secondary lesions and eliminated the presence of abdominal ascites. The results from this study show that through vessel normalization, ABT-510 increases uptake of chemotherapy drugs and can induce regression of advanced ovarian cancer.

  18. Efficacy and toxicological studies of cremophor EL free alternative paclitaxel formulation.

    Science.gov (United States)

    Utreja, Puneet; Jain, Subheet; Yadav, Subodh; Khandhuja, K L; Tiwary, A K

    2011-11-01

    In the present study, Cremophor EL free paclitaxel elastic liposomal formulation consisting of soya phosphatidylcholine and biosurfactant sodium deoxycholate was developed and optimized. The toxicological profile, antitumor efficacy and hemolytic toxicity of paclitaxel elastic liposomal formulation in comparison to Cremophor EL based marketed formulation were evaluated. Paclitaxel elastic liposomal formulations were prepared and characterized in vitro, ex-vivo and in vivo. Single dose toxicity study of paclitaxel elastic liposomal and marketed formulation was carried out in dose range of 10, 20, 40, 80, 120, 160 and 200 mg/kg. Cytotoxicity of developed formulation was evaluated using small cell lung cancer cell line (A549). Antitumor activity of developed formulation was compared with the marketed formulation using Cytoselect™ 96-well cell transformation assay. In vivo administration of paclitaxel elastic liposomal formulation into mice showed 6 fold increase in Maximum Tolerated Dose (MTD) in comparison to the marketed formulation. Similarly, LD50 (141.6 mg/kg) was also found to increase significantly than the marketed formulation (16.7 mg/kg). Result of antitumor assay revealed a high reduction of tumor density with paclitaxel elastic liposomal formulation. Reduction in hemolytic toxicity was also observed with paclitaxel elastic liposomal formulation in comparison to the marketed formulation. The carrier based approach for paclitaxel delivery demonstrated significant reduction in toxicity as compared to the Cremophor EL based marketed formulation following intra-peritoneal administration in mice model. The reduced toxicity and enhanced anti-cancer activity of elastic liposomal formulation strongly indicate its potential for safe and effective delivery of paclitaxel.

  19. A preliminary report on the effects of paclitaxel-impregnated stents on sheep nasal mucosa.

    Science.gov (United States)

    Herrmann, Brian W; Citardi, Martin J; Vogler, George; Gardner, Laura; Smith, Greg; Javer, Amin R; Burt, Helen M; Jackson, John; Kuhn, Frederick A

    2004-01-01

    Traditional frontal sinus stents serve only as mechanical devices. It has been proposed that stents also may serve as drug-delivery systems for the topical application of drugs that minimize postoperative scarring. Paclitaxel (Taxol), which has recognized antiscarring effects, may be incorporated via a polymeric formulation into standard rubber stents. The impact of topically applied paclitaxel on the morphology of the nasal mucosa is unknown. An adult sheep model was used for this study. A modified rubber T-tube stent (incorporating paclitaxel at varying dosages) was secured to each side of the septum in four animals (eight sides). An unmodified T-tube was placed on each side of one animal, a T-tube with the drug carrier (but no paclitaxel) was placed on each side of the second animal, and T-tubes with varying paclitaxel were placed on each side of the final two animals. After 4 weeks, animals were killed and the nasal mucosa was harvested. The nasal mucosa was sectioned and stained with hematoxylin and eosin. A pathologist then assessed the nasal mucosa for vascular congestion, glandular atrophy, chronic inflammation, mucosal metaplasia, and mucosal ulceration. No consistent histopathological differences were noted in the specimens. All specimens showed varying degrees of vascular congestion, glandular atrophy, chronic inflammation, and mucosal metaplasia; the paclitaxel-impregnated stents were not consistently associated with more severe mucosal injury. Finally, mucosal ulceration was noted to be very rare in all specimens. This preliminary report describes the impact of paclitaxel-impregnated stents on sheep nasal mucosa, which tolerated these stents very well. Because paclitaxel minimizes scarring reactions at very low concentrations, paclitaxel-impregnated stents may prove useful in clinical situations in which frontal sinus stenting is deemed necessary. Additional investigations with animal models, as well as clinical trials, may be warranted.

  20. Application of Osthol Induces a Resistance Response Against Powdery Mildew in Pumpkin Leave

    Directory of Open Access Journals (Sweden)

    Yong Jian Fan

    2007-09-01

    Full Text Available Plants can defend themselves against fungal infection by natural means inducedby biotic and abiotic elicitors. Osthol is a natural compound extracted from dried fruits ofCnidii Monnieri Fructus. In this study, it has been shown to not only be a fungicide withacceptable curative properties (control efficacy of 68.72, but it also showed a significantprophylactic effect (with control efficacy of 77.36 against pumpkin powdery mildew at aconcentration of 100 μg·mL-1. In pumpkin leaves with/or without inoculation ofSphaerotheca fuliginea, osthol treatment induced the accumulation of chitinase andperoxidase and enhanced the transcription of chitinase gene in non-inoculated leaves. Thepotentiation of phenylalanine amonia-lyase activity in leaves by osthol application andfollowing inoculation was absent in that with inoculation or osthol treatment, indicatingthat induced PAL in osthol-pretreated plants was inoculation-mediated. In conclusion, thisnatural compound could induce resistance response in the plant against powdery mildew.

  1. Targeted delivery and controlled release of Paclitaxel for the treatment of lung cancer using single-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Yu, Baodan; Tan, Li; Zheng, Runhui; Tan, Huo; Zheng, Lixia

    2016-01-01

    A new type of drug delivery system (DDS) based on single-walled carbon nanotubes (SWNTs) for controlled-release of the anti-cancer drug Paclitaxel (PTX) was constructed in this study. Chitosan (CHI) was non-covalently attached to the SWNTs to improve biocompatibility. Biocompatible hyaluronan was also combined to the outer CHI layer to realise the specific targeting property. The results showed that the release of PTX was pH-triggered and was better at lower pH (pH 5.5). The modified SWNTs showed a significant improvement in intracellular reactive oxygen species (ROS), which may have enhanced mitogen-activated protein kinase activation and further promoted cell apoptosis. The results of western blotting indicated that the apoptosis-related proteins were abundantly expressed in A549 cells. Lactate dehydrogenase (LDH) release assay and cell viability assay demonstrated that PTX-loaded SWNTs could destroy cell membrane integrity, thus inducing lower cell viability of the A549 cells. Thus, this targeting DDS could effectively inhibit cell proliferation and kill A549 cells, is a promising system for cancer therapy. - Highlights: • Chitosan and hyaluronan modified single-walled carbon nanotubes (SWNTs) were prepared for delivery of Paclitaxel (PTX). • Morphology, drug loading efficiency and drug release amount of the nanotubes were studied. • Cell viability, LDH, intracellular ROS levels and western blotting were evaluated. • The drug delivery system could effectively inhibit A549 cells proliferation.

  2. Targeted delivery and controlled release of Paclitaxel for the treatment of lung cancer using single-walled carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Baodan; Tan, Li; Zheng, Runhui; Tan, Huo, E-mail: tanhuo.2008@163.com; Zheng, Lixia, E-mail: 66593953@qq.com

    2016-11-01

    A new type of drug delivery system (DDS) based on single-walled carbon nanotubes (SWNTs) for controlled-release of the anti-cancer drug Paclitaxel (PTX) was constructed in this study. Chitosan (CHI) was non-covalently attached to the SWNTs to improve biocompatibility. Biocompatible hyaluronan was also combined to the outer CHI layer to realise the specific targeting property. The results showed that the release of PTX was pH-triggered and was better at lower pH (pH 5.5). The modified SWNTs showed a significant improvement in intracellular reactive oxygen species (ROS), which may have enhanced mitogen-activated protein kinase activation and further promoted cell apoptosis. The results of western blotting indicated that the apoptosis-related proteins were abundantly expressed in A549 cells. Lactate dehydrogenase (LDH) release assay and cell viability assay demonstrated that PTX-loaded SWNTs could destroy cell membrane integrity, thus inducing lower cell viability of the A549 cells. Thus, this targeting DDS could effectively inhibit cell proliferation and kill A549 cells, is a promising system for cancer therapy. - Highlights: • Chitosan and hyaluronan modified single-walled carbon nanotubes (SWNTs) were prepared for delivery of Paclitaxel (PTX). • Morphology, drug loading efficiency and drug release amount of the nanotubes were studied. • Cell viability, LDH, intracellular ROS levels and western blotting were evaluated. • The drug delivery system could effectively inhibit A549 cells proliferation.

  3. Biocatalysis of a Paclitaxel Analogue: Conversion of Baccatin III to N-Debenzoyl-N-(2-furoyl)paclitaxel and Characterization of an Amino Phenylpropanoyl CoA Transferase.

    Science.gov (United States)

    Thornburg, Chelsea K; Walter, Tyler; Walker, Kevin D

    2017-11-07

    In this study, we demonstrate an enzyme cascade reaction using a benzoate CoA ligase (BadA), a modified nonribosomal peptide synthase (PheAT), a phenylpropanoyltransferase (BAPT), and a benzoyltransferase (NDTNBT) to produce an anticancer paclitaxel analogue and its precursor from the commercially available biosynthetic intermediate baccatin III. BAPT and NDTNBT are acyltransferases on the biosynthetic pathway to the antineoplastic drug paclitaxel in Taxus plants. For this study, we addressed the recalcitrant expression of BAPT by expressing it as a soluble maltose binding protein fusion (MBP-BAPT). Further, the preparative-scale in vitro biocatalysis of phenylisoserinyl CoA using PheAT enabled thorough kinetic analysis of MBP-BAPT, for the first time, with the cosubstrate baccatin III. The turnover rate of MBP-BAPT was calculated for the product N-debenzoylpaclitaxel, a key intermediate to various bioactive paclitaxel analogues. MBP-BAPT also converted, albeit more slowly, 10-deacetylbaccatin III to N-deacyldocetaxel, a precursor of the pharmaceutical docetaxel. With PheAT available to make phenylisoserinyl CoA and kinetic characterization of MBP-BAPT, we used Michaelis-Menten parameters of the four enzymes to adjust catalyst and substrate loads in a 200-μL one-pot reaction. This multienzyme network produced a paclitaxel analogue N-debenzoyl-N-(2-furoyl)paclitaxel (230 ng) that is more cytotoxic than paclitaxel against certain macrophage cell types. Also in this pilot reaction, the versatile N-debenzoylpaclitaxel intermediate was made at an amount 20-fold greater than the N-(2-furoyl) product. This reaction network has great potential for optimization to scale-up production and is attractive in its regioselective O- and N-acylation steps that remove protecting group manipulations used in paclitaxel analogue synthesis.

  4. Formulation and pharmacokinetic evaluation of a paclitaxel nanosuspension for intravenous delivery

    Directory of Open Access Journals (Sweden)

    Wang YL

    2011-07-01

    Full Text Available Yonglu Wang1,4, Xueming Li1,2*, Liyao Wang3, Yuanlong Xu1, Xiaodan Cheng1, Ping Wei41College of Pharmacy, Nanjing University of Technology, Nanjing; 2State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing University of Technology, Nanjing; 3College of Life Science, Anhui Agricultural University, Hefei; 4College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, Nanjing, People’s Republic of China *These authors contributed equally to this work.Abstract: Paclitaxel is a diterpenoid isolated from Taxus brevifolia. It is effective for various cancers, especially ovarian and breast cancer. Due to its aqueous insolubility, it is administered dissolved in ethanol and Cremophor® EL (BASF, Ludwigshafen, Germany, which can cause serious allergic reactions. In order to eliminate Cremophor EL, paclitaxel was formulated as a nanosuspension by high-pressure homogenization. The nanosuspension was lyophilized to obtain the dry paclitaxel nanoparticles (average size, 214.4 ± 15.03 nm, which enhanced both the physical and chemical stability of paclitaxel nanoparticles. Paclitaxel dissolution was also enhanced by the nanosuspension. Differential scanning calorimetry showed that the crystallinity of paclitaxel was preserved during the high-pressure homogenization process. The pharmacokinetics and tissue distribution of paclitaxel were compared after intravenous administration of paclitaxel nanosuspension and paclitaxel injection. In rat plasma, paclitaxel nanosuspension exhibited a significantly (P < 0.01 reduced area under the concentration curve (AUC0–∞ (20.343 ± 9.119 µg · h · mL−1 vs 5.196 ± 1.426 µg · h · mL−1, greater clearance (2.050 ± 0.616 L · kg−1 · h−1 vs 0.556 ± 0.190 L · kg−1 · h−1, and shorter elimination half-life (5.646 ± 2.941 vs 3.774 ± 1.352 hours compared with the paclitaxel solution. In contrast, the paclitaxel nanosuspension resulted in a

  5. Induced resistance in tomato fruit by γ-aminobutyric acid for the control of alternaria rot caused by Alternaria alternata.

    Science.gov (United States)

    Yang, Jiali; Sun, Cui; Zhang, Yangyang; Fu, Da; Zheng, Xiaodong; Yu, Ting

    2017-04-15

    The study investigated the effect of γ-aminobutyric acid (GABA) on the control of alternaria rot in tomato fruit and the possible mechanism involved. Our results showed exogenous GABA could stimulate remarkable resistance to the alternaria rot, while it had no direct antifungal activity against Alternaria alternata. Moreover, the activities of antioxidant enzymes, including peroxidase, superoxide dismutase and catalase, along with the expression of these corresponding genes, were significantly induced in the GABA treatment. The obtained data suggested GABA induced resistance against the necrotrophic pathogen A. alternata, at least in part by activating antioxidant enzymes, restricting the levels of cell death caused by reactive oxygen species. Meanwhile, the key enzyme genes of GABA shunt, GABA transaminase and succinic-semialdehyde dehydrogenase, were found up-regulated in the GABA treatment. The activation of the GABA shunt might play a vital role in the resistance mechanism underpinning GABA-induced plant immunity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Plasmid-Mediated Resistance to Thrombin-Induced Platelet Microbicidal Protein in Staphylococci: Role of the qacA Locus

    OpenAIRE

    Kupferwasser, Leon Iri; Skurray, Ronald A.; Brown, Melissa H.; Firth, Neville; Yeaman, Michael R