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Sample records for promising chemotherapeutic agents

  1. Microencapsulation of chemotherapeutic agents

    International Nuclear Information System (INIS)

    Byun, Hong Sik

    1993-01-01

    Mixing various amounts of chemotherapeutic agents such as cisplatinum, 5-fluorouracil, mitomycin-C, and adriamycin with polymers such as poly-d, 1-lactide, ethylhydroxyethylcellulose, and polycaprolactone, several kinds of microcapsules were made. Among them, microcapsule made from ethylhydroxyethylcellulose showed best yield. Under light microscopy, the capsules were observed as particles with refractive properties. For the basic toxicity test, intraarterial administration of cisplatinum was done in 6 adult mongrel dogs. Follow-up angiography was accomplished in 2 wk intervals for 6 wks. Despite no significant difference in the histopathological examination between the embolized and normal kidneys, follow-up angiogram showed atrophy of renal cortex and diminished numbers of arterial branches in the embolized kidneys. In order to identify the structural properties of microcapsules, and to determine the drug content and the rate of release, further experiment is thought to be necessary. (Author)

  2. Alternative chemotherapeutic agents: nitrosoureas, cisplatin, irinotecan.

    Science.gov (United States)

    Carrillo, Jose A; Munoz, Claudia A

    2012-04-01

    Irinotecan, cisplatin, and nitrosoureas have a long history of use in brain tumors, with demonstrated efficacy in the adjuvant treatment of malignant gliomas. In the era of temozolomide with concurrent radiotherapy given as the standard of care, their use has shifted to treatment at progression or recurrence. Now with the widespread use of bevacizumab in the recurrent setting, irinotecan and other chemotherapies are seeing increased use in combination with bevacizumab and alone in the recurrent setting. The activity of these chemotherapeutic agents in brain tumors will likely ensure a place in the armamentarium of neuro-oncologists for many years. Published by Elsevier Inc.

  3. Chemotherapeutic agent and tracer composition and use thereof

    International Nuclear Information System (INIS)

    Babb, A. L.

    1985-01-01

    A therapeutic composition suitable for extracorporeal treatment of whole blood comprises a dialyzable chemotherapeutic agent and a dialyzable fluorescable tracer means. The removal rate of the fluorescable tracer compound from treated blood during hemodialysis is a function of the removal rate of unreacted chemotherapeutic agent present. The residual chemotherapeutic agent concentration after hemodialysis is ascertained by measuring the concentration of the fluorescable tracer compound in a dialysate using fluorometric techniques

  4. Effect of Anti-Parasite Chemotherapeutic Agents on Immune Reactions.

    Science.gov (United States)

    1980-08-01

    observations). Similar effects of a number of other alkylating agents have been noticed (9, and personal observa- tions). Similarly, corticosteroids inhibit...Wellham, L. L., and Sigel, M. M. Ef- fect of anti-cancer chemotherapeutic agents on immune reactions of mice. I. Comparison of two nitrosoureas . J...7 D-Ri138 852 EFFECT OF ANTI-PARASITE CHEMOTHERAPEUTIC AGENTS ON i/i IMMUNE REACTIONS(U) SOUTH CAROLINA UNIV COLUMBIA DEPT OF MICROBIOLOGY AND

  5. Pharmacokinetically guided dosing of (high-dose) chemotherapeutic agents

    NARCIS (Netherlands)

    Attema-de Jonge, M.E. (Milly Ellen)

    2004-01-01

    Due to variation in drug distribution, metabolism and elimination processes between patients, systemic exposure to chemotherapeutic agents may be highly variable from patient to patient after administration of similar doses. This pharmacokinetic variability may explain in part the large variability

  6. Lung Damage due to Chemotherapeutic Agents

    Directory of Open Access Journals (Sweden)

    Serdar Kalemci

    2014-12-01

    Full Text Available Chemotherapeutic drug-induced pulmonary toxicity not only emerges in cumulative doses, but also can be observed even at low dosages. Combined administration of many drugs, concurrent radiotherapy applications, opportunistic infections, lymphangitic tumor extension and pleural metastases complicate the disease diagnosis.

  7. Radiation Chemistry Studies on Chemotherapeutic Agents

    DEFF Research Database (Denmark)

    Gohn, M.; Getoff, N.; Bjergbakke, Erling

    1977-01-01

    Adrenalin has been studied as a model radiation protective agent by means of pulse radiolysis in aqueous solutions. The rate constants for the reactions of adrenalin with e–aq and OH were determined : k(e–aq+ adr—NH+2)= 7.5 × 108 dm3 mol–1 s–1, k(e–aq+ adr—NH)= 2.5 × 108 dm3 mol–1 s–1, and k......(OH + adr)= 2.2 × 1010 dm3 mol–1 s–1(pH = 9.2). e–aq attacks the amino group by splitting off methylamine, whereas OH and O–aq lead to the formation of the corresponding adducts of the cyclohexadienyl type. OH radicals can also abstract an electron from an O– group at pH > 8....

  8. Radiation chemistry studies on chemotherapeutic agents

    International Nuclear Information System (INIS)

    Gohn, M.; Getoff, N.; Bjergbakke, E.

    1977-01-01

    Adrenalin has been studied as a model radiation protective agent by means of pulse radiolysis in aqueous solutions. The rate constants for the reactions of adrenalin with e - sub(aq) and OH were determined: k(e - sub(aq) + adr -NH + 2 ) = 7.5 x 10 8 dm 3 mol -1 s -1 , k(e - sub(aq) + adr - NH) = 2.5 x 10 8 dm 3 mol -1 s -1 , and k(OH + adr) = 2.2 x 10 -10 dm 3 mol -1 s -1 (pH = 9.2). e - sub(aq) attacks the amino group by splitting off methylamine, whereas OH and O - sub(aq) lead to the formation of the corresponding adducts of the cyclohexadienyl type. OH radicals can also abstract an electron from an 0 - group at pH > 8. (author)

  9. Comparison of the oncogenic potential of several chemotherapeutic agents

    International Nuclear Information System (INIS)

    Miller, R.C.; Hall, E.J.; Osmak, R.S.

    1981-01-01

    Several chemotherapeutic drugs that have been routinely used in cancer treatment were tested for their carcinogenic potential. Two antitumor antibiotics (adriamycin and vincristine), an alkalating agent (melphalan), 5-azacytidine and the bifunctional agent cis-platinum that mimics alkylating agents and/or binds Oxygen-6 or Nitrogen-7 atoms of quanine were tested. Cell killing and cancer induction was assessed using in vitro transformation system. C3H/10T 1/2 cells, while normally exhibiting contact inhibition, can undergo transformation from normal contact inhibited cells to tumorgenic cells when exposed to chemical carcinogens. These cells have been used in the past by this laboratory to study oncogenic transformation of cells exposed to ionizing radiation and electron affinic compounds that sensitize hypoxic cells to x-rays. The endpoints of cell killing and oncogenic transformation presented here give an estimate of the carcinogenic potential of these agents

  10. The slow cell death response when screening chemotherapeutic agents.

    Science.gov (United States)

    Blois, Joseph; Smith, Adam; Josephson, Lee

    2011-09-01

    To examine the correlation between cell death and a common surrogate of death used in screening assays, we compared cell death responses to those obtained with the sulforhodamine B (SRB) cell protein-based "cytotoxicity" assay. With the SRB assay, the Hill equation was used to obtain an IC50 and final cell mass, or cell mass present at infinite agent concentrations, with eight adherent cell lines and four agents (32 agent/cell combinations). Cells were treated with high agent concentrations (well above the SRB IC50) and the death response determined as the time-dependent decrease in cells failing to bind both annexin V and vital fluorochromes by flow cytometry. Death kinetics were categorized as fast (5/32) (similar to the reference nonadherent Jurkat line), slow (17/32), or none (10/32), despite positive responses in the SRB assay in all cases. With slow cell death, a single exposure to a chemotherapeutic agent caused a slow, progressive increase in dead (necrotic) and dying (apoptotic) cells for at least 72 h. Cell death (defined by annexin and/or fluorochrome binding) did not correlate with the standard SRB "cytotoxicity" assay. With the slow cell death response, a single exposure to an agent caused a slow conversion from vital to apoptotic and necrotic cells over at least 72 h (the longest time point examined). Here, increasing the time of exposure to agent concentrations modestly above the SRB IC50 provides a method of maximizing cell kill. If tumors respond similarly, sustained low doses of chemotherapeutic agents, rather than a log-kill, maximum tolerated dose strategy may be an optimal strategy of maximizing tumor cell death.

  11. Current Research and Development of Chemotherapeutic Agents for Melanoma

    Directory of Open Access Journals (Sweden)

    Kyaw Minn Hsan

    2010-04-01

    Full Text Available Cutaneous malignant melanoma is the most lethal form of skin cancer and an increasingly common disease worldwide. It remains one of the most treatment-refractory malignancies. The current treatment options for patients with metastatic melanoma are limited and in most cases non-curative. This review focuses on conventional chemotherapeutic drugs for melanoma treatment, by a single or combinational agent approach, but also summarizes some potential novel phytoagents discovered from dietary vegetables or traditional herbal medicines as alternative options or future medicine for melanoma prevention. We explore the mode of actions of these natural phytoagents against metastatic melanoma.

  12. PET studies of potential chemotherapeutic agents: Pt. 10

    International Nuclear Information System (INIS)

    Conway, T.; Diksic, M.; McGill Univ., Montreal, PQ

    1991-01-01

    Carbon-11-labeled HECNU [1-(2-chloroethyl)-1-nitroso-3-(2-hydroxyethyl) urea] a potential chemotherapeutic agent, has been prepared by the nitrosation of the corresponding carbon-11-labeled urea, HECU, [1-(2-chloroethyl)-3-(2-hydroxyethyl) urea]. The isomeric byproduct of nitrosation, 1-(2-chloroethyl)-3-nitroso-3-(2-hydroxyethyl) urea can be efficiently removed by preparative scale HPLC on a Partisil column. ( 11 C)-HECU was prepared by reacting ethanolamine with ( 11 C)-2-chloroethyl-isocyanate which was itself prepared by reacting ( 11 C)-phosgene with 2-chloroethylamine hydrochloride suspended in dioxane at 60-65 o C. This synthesis yielded ( 11 C)-HECNU with an average radiochemical purity of 98% in an average radiochemical yield of 18% relative to the radioactivity measured at the end of the 11 C-phosgene introduction. (author)

  13. Plant-Derived Urease Inhibitors as Alternative Chemotherapeutic Agents.

    Science.gov (United States)

    Hassan, Sherif T S; Žemlička, Milan

    2016-07-01

    Inhibition of the metalloenzyme urease has important pharmacologic applications in the field of antiulcer and antigastric cancer agents. Urease is involved in many serious infections caused by Helicobacter pylori in the gastric tract as well as by Proteus and related species in the urinary tract. Although numerous studies have described several novel urease inhibitors (UIs) used for the treatment of gastric and urinary infections, all these compounds have exhibited severe side effects, toxicity, and instability. Therefore, to overcome such problems, it is necessary to search for new sources of UIs, such as natural products, that provide reduced side effects, low toxicity, greater stability, and bioavailability. As limited studies have been conducted on plant-derived UIs, this paper aims to highlight and summarize the most promising compounds isolated and identified from plants, such as terpenoids, phenolic compounds, alkaloids, and other substances with inhibitory activities against plant and bacterial ureases; these are in vitro and in vivo studies with an emphasis on structure-activity relationship studies and types of inhibition that show high and promising levels of anti-urease activity. This will aid medicinal chemists in the design and synthesis of novel and pharmacologically potent UIs useful for the development of antiulcer drugs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. APC selectively mediates response to chemotherapeutic agents in breast cancer

    International Nuclear Information System (INIS)

    VanKlompenberg, Monica K.; Bedalov, Claire O.; Soto, Katia Fernandez; Prosperi, Jenifer R.

    2015-01-01

    The Adenomatous Polyposis Coli (APC) tumor suppressor is mutated or hypermethylated in up to 70 % of sporadic breast cancers depending on subtype; however, the effects of APC mutation on tumorigenic properties remain unexplored. Using the Apc Min/+ mouse crossed to the Polyoma middle T antigen (PyMT) transgenic model, we identified enhanced breast tumorigenesis and alterations in genes critical in therapeutic resistance independent of Wnt/β-catenin signaling. Apc mutation changed the tumor histopathology from solid to squamous adenocarcinomas, resembling the highly aggressive human metaplastic breast cancer. Mechanistic studies in tumor-derived cell lines demonstrated that focal adhesion kinase (FAK)/Src/JNK signaling regulated the enhanced proliferation downstream of Apc mutation. Despite this mechanistic information, the role of APC in mediating breast cancer chemotherapeutic resistance is currently unknown. We have examined the effect of Apc loss in MMTV-PyMT mouse breast cancer cells on gene expression changes of ATP-binding cassette transporters and immunofluorescence to determine proliferative and apoptotic response of cells to cisplatin, doxorubicin and paclitaxel. Furthermore we determined the added effect of Src or JNK inhibition by PP2 and SP600125, respectively, on chemotherapeutic response. We also used the Aldefluor assay to measure the population of tumor initiating cells. Lastly, we measured the apoptotic and proliferative response to APC knockdown in MDA-MB-157 human breast cancer cells after chemotherapeutic treatment. Cells obtained from MMTV-PyMT;Apc Min/+ tumors express increased MDR1 (multidrug resistance protein 1), which is augmented by treatment with paclitaxel or doxorubicin. Furthermore MMTV-PyMT;Apc Min/+ cells are more resistant to cisplatin and doxorubicin-induced apoptosis, and show a larger population of ALDH positive cells. In the human metaplastic breast cancer cell line MDA-MB-157, APC knockdown led to paclitaxel and cisplatin

  15. Targeting cancer chemotherapeutic agents by use of lipiodol contrast medium

    International Nuclear Information System (INIS)

    Konno, T.

    1990-01-01

    Arterially administered Lipiodol Ultrafluid contrast medium selectively remained in various malignant solid tumors because of the difference in time required for the removal of Lipiodol contrast medium from normal capillaries and tumor neovasculature. Although blood flow was maintained in the tumor, even immediately after injection Lipiodol contrast medium remained in the neovasculature of the tumor. To target anti-cancer agents to tumors by using Lipiodol contrast medium as a carrier, the characteristics of the agents were examined. Anti-cancer agents had to be soluble in Lipiodol, be stable in it, and separate gradually from it so that the anti-cancer agents would selectively remain in the tumor. These conditions were found to be necessary on the basis of the measurement of radioactivity in VX2 tumors implanted in the liver of 16 rabbits that received arterial injections of 14C-labeled doxorubicin. Antitumor activities and side effects of arterial injections of two types of anti-cancer agents were compared in 76 rabbits with VX2 tumors. Oily anti-cancer agents that had characteristics essential for targeting were compared with simple mixtures of anti-cancer agents with Lipiodol contrast medium that did not have these essential characteristics. Groups of rabbits that received oily anti-cancer agents responded significantly better than groups that received simple mixtures, and side effects were observed more frequently in the groups that received the simple mixtures. These results suggest that targeting of the anti-cancer agent to the tumor is important for treatment of solid malignant tumors

  16. The Herb Medicine Formula “Chong Lou Fu Fang” Increases the Cytotoxicity of Chemotherapeutic Agents and Down-Regulates the Expression of Chemotherapeutic Agent Resistance-Related Genes in Human Gastric Cancer Cells In Vitro

    Directory of Open Access Journals (Sweden)

    Yongping Liu

    2011-01-01

    Full Text Available The herb medicine formula “Chong Lou Fu Fang” (CLFF has efficacy in inhibiting the proliferation of human gastric cancer in vitro and in vivo. To explore the potentially useful combination of CLFF with chemotherapeutic agents commonly used in gastric cancer therapy, we assess the interaction between CLFF and these chemotherapeutic agents in both SGC-7901 cell lines and BGC-823 cell lines using a median effect analysis and apoptosis analysis, and we also investigate the influence of CLFF on chemotherapeutic agent-associated gene expression. The synergistic analysis indicated that CLFF had a synergistic effect on the cytotoxicity of 5-fluorouracil (5-FU in a relative broad dose inhibition range (20–95% fraction affected in SGC-7901cell lines and 5–65% fraction affected in BGC-823 cell lines, while the synergistic interaction between CLFF and oxaliplatin or docetaxel only existed in a low dose inhibition range (≤50% fraction affected in both cell lines. Combination of CLFF and chemotherapeutic agents could also induce apoptosis in a synergistic manner. After 24 h, CLFF alone or CLFF combination with chemotherapeutic agents could significantly suppress the levels of expression of chemotherapeutic agent resistance related genes in gastric cancer cells. Our findings indicate that there are useful synergistic interactions between CLFF and chemotherapeutic agents in gastric cancer cells, and the possible mechanisms might be partially due to the down-regulation of chemotherapeutic agent resistance related genes and the synergistic apoptotic effect.

  17. Induction of cell death by chemotherapeutic methylating agents

    International Nuclear Information System (INIS)

    Quiros Barrantes, Steve

    2012-01-01

    The mechanism of cell death induced by O 6 MeG has been investigated and inhibition of homologous recombination as a strategy for sensitization of tumor cells against methylating agents S N 1. Dependence of the cell cycle was determined toxic responses triggered by O''6 MeG and evaluated by proliferation assays if apoptotic cells have originated exclusively from the second post-treatment cycle. Dependence of O''6 MeG was found at DSB formation. The activation of the control points of the cell cycle and induction of apoptosis is generated during the second cell cycle. Additionally, a portion of the cells has been determined that triggers apoptosis in subsequent generations in the second cell cycle. Inhibition of homologous recombination has been a reasonable strategy to increase S N 1 alkylating agent effectiveness. Evidence has been provided in NHEJ dependent inhibition of DNA-PK that not significantly sensitizes the glioblastoma cells against temozolomide [es

  18. Hypertension induced by chemotherapeutic and immunosuppresive agents: a new challenge.

    Science.gov (United States)

    Abi Aad, Simon; Pierce, Matthew; Barmaimon, Guido; Farhat, Fadi S; Benjo, Alexandre; Mouhayar, Elie

    2015-01-01

    Hypertension is a common adverse effect of certain anti neoplastic therapy. The incidence and severity of hypertension are dependent mainly on the type and the dose of the drug. We reviewed the literature for studies that reported the effect of anti neoplastic agents on blood pressure in patients with malignancies. The medical databases of PubMed, MEDLINE and EMBASE were searched for articles published in English between 1955 and June 2012. The effects of specific agents on blood pressure were analyzed. Hypertension is a prevalent adverse effect of many of the new chemotherapy agents such as VEGF inhibitors. Approximately 30% of patients treated for cancer will have concomitant hypertension, and crucial chemotherapy can sometimes be stopped due to new onset or worsening severe hypertension. The importance of a timely diagnosis and optimal management of HTN in this group of patients is related to the facts that HTN is a well established risk factor for chemotherapy-induced cardiotoxicity and if left untreated, can alter cancer management and result in dose reductions or termination of anti-cancer treatments as well as life-threatening end organ damage. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  19. Effect of the nitroimidazole Ro 03-8799 on the activity of chemotherapeutic agents against a murine tumour in vivo.

    OpenAIRE

    Sheldon, P. W.; Gibson, P.

    1984-01-01

    The effect of the 2-nitroimidazole Ro 03-8799 (8799) on the activity of 11 chemotherapeutic agents against the anaplastic MT tumour in mice has been determined by soft agar cloning. The 8799, whilst producing little cytotoxicity by itself, potentiated the cytotoxic actions of the alkylating agents melphalan and cyclophosphamide, and the nitrosoureas BCNU, CCNU and MeCCNU. This potentiation was influenced by the time interval between the administration of 8799 and the chemotherapeutic agents, ...

  20. Polymeric Micelles with Ionic Cores Containing Biodegradable Crosslinks for Delivery of Chemotherapeutic Agents

    OpenAIRE

    Kim, Jong Oh; Sahay, Gaurav; Kabanov, Alexander V.; Bronich, Tatiana K.

    2010-01-01

    Novel functional polymeric nanocarriers with ionic cores containing biodegradable cross-links were developed for delivery of chemotherapeutic agents. Block ionomer complexes (BIC) of poly(ethylene oxide)-b-poly(methacylic acid) (PEO-b-PMA) and divalent metal cations (Ca2+) were utilized as templates. Disulfide bonds were introduced into the ionic cores by using cystamine as a biodegradable cross-linker. The resulting cross-linked micelles with disulfide bonds represented soft, hydrogel-like n...

  1. Effects of cytotoxic chemotherapeutic agents on split-dose repair in intestinal crypt cells

    International Nuclear Information System (INIS)

    Phillips, Theodore L.; Ross, Glenda Y.

    1997-01-01

    Purpose: Many cancer chemotherapeutic agents interact with radiation to enhance the amount of radiation damage observed in both tumor and normal tissues. It is important to predict this interaction and to determine the effect of drug on sublethal damage repair. To evaluate for effects in rapid renewing normal tissues, the intestinal crypt cell in vivo assay is an excellent one to employ. These studies investigate the effect of eleven cancer chemotherapeutic drugs on split-dose repair in the intestinal crypt cell of the mouse. Methods and Materials: LAF1 male mice, age 10-12 weeks, were exposed to whole-body irradiation with orthovoltage x-rays delivered as a single dose or as equally divided doses delivered with intervals between the two exposures of 2 to 24 h. In the experimental group, the cancer chemotherapeutic agent was administered intraperitoneally 2 h before the first radiation dose. At 3.6 days after the second irradiation, the mice were sacrificed; the jejunum was removed, fixed, and sectioned for light microscopy. The number of regenerating crypts were counted and corrected to represent the number of surviving cells per circumference. Results: Of the eleven drugs tested, only carmustine eliminated split-dose repair. Cisplatin delayed repair, and methotrexate caused marked synchronization obliterating the observation of split-dose repair. Conclusions: Most cytotoxic chemotherapeutic agents do not inhibit sublethal damage repair in intestinal crypt cells when given 2 h before the first radiation exposure. Absence of the initial increase in survival seen with split-dose radiation is noted with carmustine and high-dose methotrexate

  2. Interactions of radiation with novel chemotherapeutic agents: Taxanes and nucleoside analogs

    International Nuclear Information System (INIS)

    Milas, Luka

    1997-01-01

    The combination of chemotherapeutic agents and radiotherapy is an appealing approach to improving the results of cancer treatment. By their independent action or interactive action chemotherapeutic drugs reduce cell burden in tumors undergoing radiotherapy, thereby increasing the chances of tumor control. In addition, the drugs may spatially cooperate with radiotherapy through their systemic action on metastatic disease. Recently, a number of new chemotherapeutic agents have been introduced for cancer treatment, which in addition have high potential to increase therapeutic ratio of radiotherapy. These agents include taxanes (paclitaxel and docetaxel) and the nucleoside analogs fludarabine and gemcitabine. Paclitaxel is a natural product isolated from the bark of Taxus brevifolia and taxotere is a semisynthetic analogue of paclitaxel prepared from needle extracts of Taxus baccata. By binding to cellular tubulin structures, taxanes interfere with tubulin polymerization and promote microtubule assembly, resulting in accumulation of cells in the radiosensitive G2 and M phases of the cell cycle. In vivo studies have demonstrated two major mechanisms of tumor radioenhancement by taxanes: mitotic arrest and tumor reoxygenation. Fludarabine and gemcitabine inhibit DNA synthesis and the repair of radiation-induced chromosome breaks. The mechanism of their radioenhancing activity include inhibition of repair of radiation induced damage, apoptosis induction and cell cycle synchronization. Because both classes of these agents affect radioresponse of normal dose-limiting tissues much less than that of tumors, they can greatly increase therapeutic ratio of radiotherapy. The objective of this course is to overview the rationale for using these drugs as radioenhancing agents, the experimental findings in preclinical studies, the mechanisms of their interaction, and the clinical application of these agents

  3. Hormetic Effect of Berberine Attenuates the Anticancer Activity of Chemotherapeutic Agents.

    Directory of Open Access Journals (Sweden)

    Jiaolin Bao

    Full Text Available Hormesis is a phenomenon of biphasic dose response characterized by exhibiting stimulatory or beneficial effects at low doses and inhibitory or toxic effects at high doses. Increasing numbers of chemicals of various types have been shown to induce apparent hormetic effect on cancer cells. However, the underlying significance and mechanisms remain to be elucidated. Berberine, one of the major active components of Rhizoma coptidis, has been manifested with notable anticancer activities. This study aims to investigate the hormetic effect of berberine and its influence on the anticancer activities of chemotherapeutic agents. Our results demonstrated that berberine at low dose range (1.25 ~ 5 μM promoted cell proliferation to 112% ~170% of the untreated control in various cancer cells, while berberine at high dose rage (10 ~ 80 μM inhibited cell proliferation. Further, we observed that co-treatment with low dose berberine could significantly attenuate the anticancer activity of chemotherapeutic agents, including fluorouracil (5-FU, camptothecin (CPT, and paclitaxel (TAX. The hormetic effect and thereby the attenuated anticancer activity of chemotherapeutic drugs by berberine may attributable to the activated protective stress response in cancer cells triggered by berberine, as evidenced by up-regulated MAPK/ERK1/2 and PI3K/AKT signaling pathways. These results provided important information to understand the potential side effects of hormesis, and suggested cautious application of natural compounds and relevant herbs in adjuvant treatment of cancer.

  4. Genome-Wide Mutational Signature of the Chemotherapeutic Agent Mitomycin C in Caenorhabditis elegans.

    Science.gov (United States)

    Tam, Annie S; Chu, Jeffrey S C; Rose, Ann M

    2015-11-12

    Cancer therapy largely depends on chemotherapeutic agents that generate DNA lesions. However, our understanding of the nature of the resulting lesions as well as the mutational profiles of these chemotherapeutic agents is limited. Among these lesions, DNA interstrand crosslinks are among the more toxic types of DNA damage. Here, we have characterized the mutational spectrum of the commonly used DNA interstrand crosslinking agent mitomycin C (MMC). Using a combination of genetic mapping, whole genome sequencing, and genomic analysis, we have identified and confirmed several genomic lesions linked to MMC-induced DNA damage in Caenorhabditis elegans. Our data indicate that MMC predominantly causes deletions, with a 5'-CpG-3' sequence context prevalent in the deleted regions of DNA. Furthermore, we identified microhomology flanking the deletion junctions, indicative of DNA repair via nonhomologous end joining. Based on these results, we propose a general repair mechanism that is likely to be involved in the biological response to this highly toxic agent. In conclusion, the systematic study we have described provides insight into potential sequence specificity of MMC with DNA. Copyright © 2016 Tam et al.

  5. Genome-Wide Mutational Signature of the Chemotherapeutic Agent Mitomycin C in Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Annie S. Tam

    2016-01-01

    Full Text Available Cancer therapy largely depends on chemotherapeutic agents that generate DNA lesions. However, our understanding of the nature of the resulting lesions as well as the mutational profiles of these chemotherapeutic agents is limited. Among these lesions, DNA interstrand crosslinks are among the more toxic types of DNA damage. Here, we have characterized the mutational spectrum of the commonly used DNA interstrand crosslinking agent mitomycin C (MMC. Using a combination of genetic mapping, whole genome sequencing, and genomic analysis, we have identified and confirmed several genomic lesions linked to MMC-induced DNA damage in Caenorhabditis elegans. Our data indicate that MMC predominantly causes deletions, with a 5′-CpG-3′ sequence context prevalent in the deleted regions of DNA. Furthermore, we identified microhomology flanking the deletion junctions, indicative of DNA repair via nonhomologous end joining. Based on these results, we propose a general repair mechanism that is likely to be involved in the biological response to this highly toxic agent. In conclusion, the systematic study we have described provides insight into potential sequence specificity of MMC with DNA.

  6. In vitro sensitivity of Trichomonas vaginalis and Candida albicans to chemotherapeutic agents.

    Science.gov (United States)

    Lövgren, T; Salmela, I

    1978-06-01

    Strains of fresh clinical isolates of Trichomonas vaginalis and Candida albicans have been tested in vitro for their sensitivity to eight drugs used in the therapy of monilial and trichomonal vaginitis. Three of the chemotherapeutic agents, chlorchinaldol, clotrimazole and broxyquinoline were effective against both organisms. Tinidazole and metronidazole were active against T. vaginalis. The strains of C. albicans were also sensitive to trichomycin, natamycin and nystatin. Tinidazole was the most effective trichomonacide, clotrimazole and chlorchinaldol were most effective against C. albicans, while chlorchinaldol had the best in vitro effect against both organisms. The ranges of the MICs are compared to values previously reported.

  7. Measuring the Acoustic Release of a Chemotherapeutic Agent from Folate-Targeted Polymeric Micelles.

    Science.gov (United States)

    Abusara, Ayah; Abdel-Hafez, Mamoun; Husseini, Ghaleb

    2018-08-01

    In this paper, we compare the use of Bayesian filters for the estimation of release and re-encapsulation rates of a chemotherapeutic agent (namely Doxorubicin) from nanocarriers in an acoustically activated drug release system. The study is implemented using an advanced kinetic model that takes into account cavitation events causing the antineoplastic agent's release from polymeric micelles upon exposure to ultrasound. This model is an improvement over the previous representations of acoustic release that used simple zero-, first- and second-order release and re-encapsulation kinetics to study acoustically triggered drug release from polymeric micelles. The new model incorporates drug release and micellar reassembly events caused by cavitation allowing for the controlled release of chemotherapeutics specially and temporally. Different Bayesian estimators are tested for this purpose including Kalman filters (KF), Extended Kalman filters (EKF), Particle filters (PF), and multi-model KF and EKF. Simulated and experimental results are used to verify the performance of the above-mentioned estimators. The proposed methods demonstrate the utility and high-accuracy of using estimation methods in modeling this drug delivery technique. The results show that, in both cases (linear and non-linear dynamics), the modeling errors are expensive but can be minimized using a multi-model approach. In addition, particle filters are more flexible filters that perform reasonably well compared to the other two filters. The study improved the accuracy of the kinetic models used to capture acoustically activated drug release from polymeric micelles, which may in turn help in designing hardware and software capable of precisely controlling the delivered amount of chemotherapeutics to cancerous tissue.

  8. 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.

  9. Alkylating chemotherapeutic agents cyclophosphamide and melphalan cause functional injury to human bone marrow-derived mesenchymal stem cells.

    Science.gov (United States)

    Kemp, Kevin; Morse, Ruth; Sanders, Kelly; Hows, Jill; Donaldson, Craig

    2011-07-01

    The adverse effects of melphalan and cyclophosphamide on hematopoietic stem cells are well-known; however, the effects on the mesenchymal stem cells (MSCs) residing in the bone marrow are less well characterised. Examining the effects of chemotherapeutic agents on patient MSCs in vivo is difficult due to variability in patients and differences in the drug combinations used, both of which could have implications on MSC function. As drugs are not commonly used as single agents during high-dose chemotherapy (HDC) regimens, there is a lack of data comparing the short- or long-term effects these drugs have on patients post treatment. To help address these problems, the effects of the alkylating chemotherapeutic agents cyclophosphamide and melphalan on human bone marrow MSCs were evaluated in vitro. Within this study, the exposure of MSCs to the chemotherapeutic agents cyclophosphamide or melphalan had strong negative effects on MSC expansion and CD44 expression. In addition, changes were seen in the ability of MSCs to support hematopoietic cell migration and repopulation. These observations therefore highlight potential disadvantages in the use of autologous MSCs in chemotherapeutically pre-treated patients for future therapeutic strategies. Furthermore, this study suggests that if the damage caused by chemotherapeutic agents to marrow MSCs is substantial, it would be logical to use cultured allogeneic MSCs therapeutically to assist or repair the marrow microenvironment after HDC.

  10. Bacteriophages show promise as antimicrobial agents.

    Science.gov (United States)

    Alisky, J; Iczkowski, K; Rapoport, A; Troitsky, N

    1998-01-01

    The emergence of antibiotic-resistant bacteria has prompted interest in alternatives to conventional drugs. One possible option is to use bacteriophages (phage) as antimicrobial agents. We have conducted a literature review of all Medline citations from 1966-1996 that dealt with the therapeutic use of phage. There were 27 papers from Poland, the Soviet Union, Britain and the U.S.A. The Polish and Soviets administered phage orally, topically or systemically to treat a wide variety of antibiotic-resistant pathogens in both adults and children. Infections included suppurative wound infections, gastroenteritis, sepsis, osteomyelitis, dermatitis, empyemas and pneumonia; pathogens included Staphylococcus, Streptococcus, Klebsiella, Escherichia, Proteus, Pseudomonas, Shigella and Salmonella spp. Overall, the Polish and Soviets reported success rates of 80-95% for phage therapy, with rare, reversible gastrointestinal or allergic side effects. However, efficacy of phage was determined almost exclusively by qualitative clinical assessment of patients, and details of dosages and clinical criteria were very sketchy. There were also six British reports describing controlled trials of phage in animal models (mice, guinea pigs and livestock), measuring survival rates and other objective criteria. All of the British studies raised phage against specific pathogens then used to create experimental infections. Demonstrable efficacy against Escherichia, Acinetobacter, Pseudomonas and Staphylococcus spp. was noted in these model systems. Two U.S. papers dealt with improving the bioavailability of phage. Phage is sequestered in the spleen and removed from circulation. This can be overcome by serial passage of phage through mice to isolate mutants that resist sequestration. In conclusion, bacteriophages may show promise for treating antibiotic resistant pathogens. To facilitate further progress, directions for future research are discussed and a directory of authors from the reviewed

  11. Stability Studies of Certain Chemotherapeutic Agents Following Gamma Irradiation and Silver Nanoparticles Conjugation

    International Nuclear Information System (INIS)

    El-Sayyad, Gh.E.S.M.

    2014-01-01

    The Chemical stability of drug is of great importance since it becomes less effective as it undergoes degradation in case of applied of gamma irradiation process. The application of gamma irradiation for different chemotherapeutic agents Such as (ofloxacin, sodium ampicillin, sodium cefotaxime, gentamycin and amoxicillin) and studying the effect of applied doses on chemical structure and biological activity of the irradiated antibiotics compared to unirradiated ones was studied by ultraviolet-Visible spectrophotometer (UV-Visible), Fourier transform infrared spectroscopy measurements (FTIR spectra) and high performance liquid chromatography (HPLC) in addition to microbiological assay were run before and after irradiation to probe any change after irradiation. The results showed that all of the irradiated compounds remain stable and radio resistant; retaining their structure and activity unchanged up to 25 KGy. The radiation-induced AgNPs synthesis is a simple, clean which involves radiolysis of aqueous solution that provides an efficient method to reduce metal ions. Also, in this study, Bacillus megaterium was found to be an effective biological tool for the extracellular biosynthesis of stable AgNPs which are highly stable and this method has advantages over other methods as the organism used here is safe. This study would therefore lead to an easy procedure for producing silver nanoparticles with the added advantage of bio safety. The Synthesized AgNPs exhibit remarkable antimicrobial activity against both Gram-positive and Gram negative bacterial strains regardless of their drug-resistant mechanisms. The bactericidal activity have proved that AgNPs kill bacteria at such low concentrations (units of ppm), which Stability Studies of Certain Chemotherapeutic Agents Following Gamma Irradiation and Silver Nanoparticles Conjugation. do not reveal acute toxic effects on human cell, in addition to overcoming resistance, and lowering cost when compared to conventional

  12. Pyrimidine nucleoside analogues, potential chemotherapeutic agents, and substrates/inhibitors in various enzyme systems

    International Nuclear Information System (INIS)

    Kulikowski, T.; Bretner, M.; Felczak, K.; Drabikowska, A.; Shugar, D.

    1998-01-01

    Full text. Pyrimidine nucleoside analogues are an important class of compounds with antimetabolic (antitumor, antiparasitic and antiviral) properties. The synthesis of thiated nucleoside and nucleotide analogues, determination of structures, conformation and dissociation constans, their potential chemotherapeutic activities, and their substrate/inhibitor properties in various enzyme systems, with emphasis on enzymes related to chemotherapeutic activities, were investigated. In the series of thionated inhibitors of thymidylate synthase (TS), potential antitumor agents, regioselective syntheses were elaborated for 2- and 4-thio, and 2,4-dithio derivatives of 2'-deoxyuridine (dUrd), 5-fluoro-2'-deoxyuridine (FdUrd), and several other 5-fluoro-, 5-bromo- and 5-trifluoromethyl congeners, and the 2-thio derivatives of FdUrd and its α-anomer, which proved to be selective agents with high cytotoxicities correlated with the inhibitory activities vs TS of their corresponding 5'-monophosphates. Regioslective syntheses were also elaborated for 2'-deoxycytidin e and 5-fluoro-2'-deoxycitidine derivatives. Solution conformation of these nucleosides were deduced from high-resolution (500 MHz) 1 H NMR spectra. Substrate/inhibitor properties of 2-thio-2'-deoxycitidine (S 2 dCyd) and 5-fluoro-2-thio-2'-deoxycitidine ( S 2 FdCyd) with respect to human leukemic spleen deoxycytidine kinase have been examined. Both are substrates, and also good inhibitors, of phosphorylation of 2'-deoxycitidine and 2'-deoxyadenosine. Particular attention was directed to the specificity of t he NTP phosphate donor for several nucleoside kinases, and procedures have been developed for distinguishing between ATP and other NTP donors, a problem of importance in chemotherapy with nucleoside analogues. Biological properties of the newly synthetize d thiated pyrimidine 2',3'-dideoxy-3'-fluoronucleosides, S 2 ,3'-FddUrd and S 2 ,3'-FddThd, were also investigated. Thiated 3'-fluoronucleosides were moderate

  13. Agent-Based Computing: Promise and Perils

    OpenAIRE

    Jennings, N. R.

    1999-01-01

    Agent-based computing represents an exciting new synthesis both for Artificial Intelligence (AI) and, more genrally, Computer Science. It has the potential to significantly improve the theory and practice of modelling, designing and implementing complex systems. Yet, to date, there has been little systematic analysis of what makes an agent such an appealing and powerful conceptual model. Moreover, even less effort has been devoted to exploring the inherent disadvantages that stem from adoptin...

  14. Suspension culture combined with chemotherapeutic agents for sorting of breast cancer stem cells

    International Nuclear Information System (INIS)

    Li, Hai-zhi; Yi, Tong-bo; Wu, Zheng-yan

    2008-01-01

    Cancer stem cell (CSC) hypothesis has not been well demonstrated by the lack of the most convincing evidence concerning a single cell capable of giving rise to a tumor. The scarcity in quantity and improper approaches for isolation and purification of CSCs have become the major obstacles for great development in CSCs. Here we adopted suspension culture combined with anticancer regimens as a strategy for screening breast cancer stem cells (BrCSCs). BrCSCs could survive and be highly enriched in non-adherent suspension culture while chemotherapeutic agents could destroy most rapidly dividing cancer cells and spare relatively quiescent BrCSCs. TM40D murine breast cancer cells were cultured in serum-free medium. The expression of CD44 + CD24 - was measured by flow cytometry. Cells of passage 10 were treated in combination with anticancer agents pacilitaxel and epirubicin at different peak plasma concentrations for 24 hours, and then maintained under suspension culture. The rate of apoptosis was examined by flow cytometry with Annexin-V fluorescein isothiocyanate (FITC)/propidium iodide (PI) double staining method. Selected cells in different amounts were injected subcutaneously into BALB/C mice to observe tumor formation. Cells of passage 10 in suspension culture had the highest percentage of CD44 + CD24 - (about 77 percent). A single tumor cell in 0.35 PPC could generate tumors in 3 of 20 BALB/C mice. Suspension culture combined with anticancer regimens provides an effective means of isolating, culturing and purifying BrCSCs

  15. Risk factors for the leakage of chemotherapeutic agents into systemic circulation after transcatheter arterial chemoembolization of hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Ming-Yen Hsieh

    2011-10-01

    Full Text Available This prospective study was to investigate the possible risk factors for the leakage of chemotherapeutic agent into the systemic circulation after transcatheter arterial chemoembolization (TACE of hepatocellular carcinoma (HCC. Peripheral plasma concentrations of chemotherapeutic agents were determined at 1 hour and 72 hours after TACE by high-performance liquid chromatography in 53 patients. HCC were divided into three types namely single nodule (<5 cm, multiple nodules (all <5 cm, and main nodule measuring 5 cm or more. Forty-four patients (83% showed detectable chemotherapeutic concentrations within 72 hours after TACE. Patients with single nodular-type HCC had lower incidence of detectable plasma chemotherapeutic agents after TACE than the other two groups (all p<0.05. The injected doses of lipiodol, epirubicin, and mitomycin C were lower in patients without detection than in patients with detectable chemotherapeutic agents (all p<0.05. Multivariate logistic regression showed that tumor type and injected dose of lipiodol were two independent risk factors for the leakage of mitomycin C at 1 hour after TACE (all p<0.05, and the injected dose of mitomycin C was the risk factor for the leakage of epirubicin at 1 hour after TACE (p<0.05. In conclusion, multiple nodular type and large nodule measuring 5 cm or more have a risk of leakage of mitomycin C after TACE. Injected dose of lipiodol and mitomycin C as risk factor for the leakage of mitomycin C and epirubicin respectively may be because of competition of their injected volume within the limited space of target.

  16. Polymeric micelles with ionic cores containing biodegradable cross-links for delivery of chemotherapeutic agents.

    Science.gov (United States)

    Kim, Jong Oh; Sahay, Gaurav; Kabanov, Alexander V; Bronich, Tatiana K

    2010-04-12

    Novel functional polymeric nanocarriers with ionic cores containing biodegradable cross-links were developed for delivery of chemotherapeutic agents. Block ionomer complexes (BIC) of poly(ethylene oxide)-b-poly(methacylic acid) (PEO-b-PMA) and divalent metal cations (Ca(2+)) were utilized as templates. Disulfide bonds were introduced into the ionic cores by using cystamine as a biodegradable cross-linker. The resulting cross-linked micelles with disulfide bonds represented soft, hydrogel-like nanospheres and demonstrated a time-dependent degradation in the conditions mimicking the intracellular reducing environment. The ionic character of the cores allowed to achieve a very high level of doxorubicin (DOX) loading (50% w/w) into the cross-linked micelles. DOX-loaded degradable cross-linked micelles exhibited more potent cytotoxicity against human A2780 ovarian carcinoma cells as compared to micellar formulations without disulfide linkages. These novel biodegradable cross-linked micelles are expected to be attractive candidates for delivery of anticancer drugs.

  17. Immunological detection and quantification of DNA components structurally modified by alkylating carcinogens, mutagens and chemotherapeutic agents

    International Nuclear Information System (INIS)

    Rajewsky, M.F.

    1983-01-01

    The detection and quantification of defined reaction products of chemical mutagens and carcinogens (and of many cancer chemotherapeutic agents) with DNA require highly sensitive analytical techniques. The exceptional capability of immunoglobulins to recognize subtle alterations of molecular structure (especially when monoclonal antibodies are used to maximize specificity), outstanding sensitivity of immunoanalysis by high-affinity antibodies, and the fact that radioactively-labelled agents are not required suggest the utility of a radioimmunoassay to recognize and quantitate alkylated DNA products. We have recently developed a set of high-affinity monoclonal antibodies (secreted by mouse x mouse as well as by rat x rat hybridomas; antibody affinity constants, 10 9 to > 10 10 lmol) specifically directed against several DNA alkylation products with possible relevance in relation to both mutagenesis and malignant transformation of mammalian cells. These alkylation products include 0 6 -N-butyldeoxyguanosine, and 0 4 -ethyldeoxythymidine. When used in a radioimmunassay, an antibody specific for 0 6 -ethyldeoxyguanosine, for example, will detect this product at an 0 6 -ethyldeoxyguanosine/deoxyguanosine molar ratio of approx. 3 x 10 -7 in a hydrolysate of 100 ug of DNA. The limit of detection can be lowered further if the respective alkyldeoxynucleosides are separated by HPLC from the DNA hydrolysate prior to the RIA. The anti-alkyldeoxynucleoside monoclonal antibodies can also be used to visualize, by immunostaining and fluorescence microscopy combined with electronic image intensification, specific alkylation products in the nuclear DNA of individual cells, and to localize structurally modified bases in double-stranded DNA molecules by transmission electron microscopy

  18. Using a device for continuous infusion of a chemotherapeutic agent in the perception of the oncologic patient

    Directory of Open Access Journals (Sweden)

    Julianna de Freitas Siqueira

    2014-01-01

    Full Text Available This is a qualitative study whose aim was to describe the perception of an oncologic patient regarding the use of a device for continuous infusion of a chemotherapeutic agent. It was carried out with eight patients, through a semi-structured interview with this guiding question: “How do you feel about using a device for continuous infusion of a chemotherapeutic agent?”. Three categories emerged: avoiding hospitalization; unveiling the unknown; and performing activities. The patient highlights the benefit of going home and the possibility of performing activities, despite the anxiety regarding the presence of the device and the new experience in her/his daily life. The results were important to direct the guidelines related to the positive and negative aspects of this technology.

  19. Anti-cancer effects of newly developed chemotherapeutic agent, glycoconjugated palladium (II) complex, against cisplatin-resistant gastric cancer cells

    International Nuclear Information System (INIS)

    Tanaka, Mamoru; Kamiya, Takeshi; Joh, Takashi; Kataoka, Hiromi; Yano, Shigenobu; Ohi, Hiromi; Kawamoto, Keisuke; Shibahara, Takashi; Mizoshita, Tsutomu; Mori, Yoshinori; Tanida, Satoshi

    2013-01-01

    Cisplatin (CDDP) is the most frequently used chemotherapeutic agent for various types of advanced cancer, including gastric cancer. However, almost all cancer cells acquire resistance against CDDP, and this phenomenon adversely affects prognosis. Thus, new chemotherapeutic agents that can overcome the CDDP-resistant cancer cells will improve the survival of advanced cancer patients. We synthesized new glycoconjugated platinum (II) and palladium (II) complexes, [PtCl 2 (L)] and [PdCl 2 (L)]. CDDP-resistant gastric cancer cell lines were established by continuous exposure to CDDP, and gene expression in the CDDP-resistant gastric cancer cells was analyzed. The cytotoxicity and apoptosis induced by [PtCl 2 (L)] and [PdCl 2 (L)] in CDDP-sensitive and CDDP-resistant gastric cancer cells were evaluated. DNA double-strand breaks by drugs were assessed by evaluating phosphorylated histone H2AX. Xenograft tumor mouse models were established and antitumor effects were also examined in vivo. CDDP-resistant gastric cancer cells exhibit ABCB1 and CDKN2A gene up-regulation, as compared with CDDP-sensitive gastric cancer cells. In the analyses of CDDP-resistant gastric cancer cells, [PdCl 2 (L)] overcame cross-resistance to CDDP in vitro and in vivo. [PdCl 2 (L)] induced DNA double-strand breaks. These results indicate that [PdCl 2 (L)] is a potent chemotherapeutic agent for CDDP-resistant gastric cancer and may have clinical applications

  20. Activation of the human immune system by chemotherapeutic or targeted agents combined with the oncolytic parvovirus H-1

    International Nuclear Information System (INIS)

    Moehler, Markus; Sieben, Maike; Roth, Susanne; Springsguth, Franziska; Leuchs, Barbara; Zeidler, Maja; Dinsart, Christiane; Rommelaere, Jean; Galle, Peter R

    2011-01-01

    Parvovirus H-1 (H-1PV) infects and lyses human tumor cells including melanoma, hepatoma, gastric, colorectal, cervix and pancreatic cancers. We assessed whether the beneficial effects of chemotherapeutic agents or targeted agents could be combined with the oncolytic and immunostimmulatory properties of H-1PV. Using human ex vivo models we evaluated the biological and immunological effects of H-1PV-induced tumor cell lysis alone or in combination with chemotherapeutic or targeted agents in human melanoma cells +/- characterized human cytotoxic T-cells (CTL) and HLA-A2-restricted dendritic cells (DC). H-1PV-infected MZ7-Mel cells showed a clear reduction in cell viability of >50%, which appeared to occur primarily through apoptosis. This correlated with viral NS1 expression levels and was enhanced by combination with chemotherapeutic agents or sunitinib. Tumor cell preparations were phagocytosed by DC whose maturation was measured according to the treatment administered. Immature DC incubated with H-1PV-induced MZ7-Mel lysates significantly increased DC maturation compared with non-infected or necrotic MZ7-Mel cells. Tumor necrosis factor-α and interleukin-6 release was clearly increased by DC incubated with H-1PV-induced SK29-Mel tumor cell lysates (TCL) and was also high with DC-CTL co-cultures incubated with H-1PV-induced TCL. Similarly, DC co-cultures with TCL incubated with H-1PV combined with cytotoxic agents or sunitinib enhanced DC maturation to a greater extent than cytotoxic agents or sunitinib alone. Again, these combinations increased pro-inflammatory responses in DC-CTL co-cultures compared with chemotherapy or sunitinib alone. In our human models, chemotherapeutic or targeted agents did not only interfere with the pronounced immunomodulatory properties of H-1PV, but also reinforced drug-induced tumor cell killing. H-1PV combined with cisplatin, vincristine or sunitinib induced effective immunostimulation via a pronounced DC maturation, better cytokine

  1. The Promise of Neuroprotective Agents in Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    Judith ePotashkin

    2011-11-01

    Full Text Available Parkinson’s Disease is characterized by loss of dopamine neurons in the substantia nigra of the brain. Since there are limited treatment options for PD, neuroprotective agents are currently being tested as a means to slow disease progression. Agents targeting oxidative stress, mitochondrial dysfunction and inflammation are prime candidates for neuroprotection. This review identifies Rasagiline, Minocycline and creatine, as the most promising neuroprotective agents for PD, and they are all currently in phase III trials. Other agents possessing protective characteristics in delaying PD include stimulants, vitamins, supplements, and other drugs. Additionally, combination therapies also show benefits in slowing PD progression. The identification of neuroprotective agents for PD provides us with therapeutic opportunities for modifying the course of disease progression and, perhaps, reducing the risk of onset when preclinical biomarkers become available.

  2. Suppression of NRF2–ARE activity sensitizes chemotherapeutic agent-induced cytotoxicity in human acute monocytic leukemia cells

    International Nuclear Information System (INIS)

    Peng, Hui; Wang, Huihui; Xue, Peng; Hou, Yongyong; Dong, Jian; Zhou, Tong; Qu, Weidong; Peng, Shuangqing; Li, Jin; Carmichael, Paul L.; Nelson, Bud; Clewell, Rebecca; Zhang, Qiang; Andersen, Melvin E.; Pi, Jingbo

    2016-01-01

    Nuclear factor erythroid 2-related factor 2 (NRF2), a master regulator of the antioxidant response element (ARE)-dependent transcription, plays a pivotal role in chemical detoxification in normal and tumor cells. Consistent with previous findings that NRF2–ARE contributes to chemotherapeutic resistance of cancer cells, we found that stable knockdown of NRF2 by lentiviral shRNA in human acute monocytic leukemia (AML) THP-1 cells enhanced the cytotoxicity of several chemotherapeutic agents, including arsenic trioxide (As 2 O 3 ), etoposide and doxorubicin. Using an ARE-luciferase reporter expressed in several human and mouse cells, we identified a set of compounds, including isonicotinic acid amides, isoniazid and ethionamide, that inhibited NRF2–ARE activity. Treatment of THP-1 cells with ethionamide, for instance, significantly reduced mRNA expression of multiple ARE-driven genes under either basal or As 2 O 3 -challenged conditions. As determined by cell viability and cell cycle, suppression of NRF2–ARE by ethionamide also significantly enhanced susceptibility of THP-1 and U937 cells to As 2 O 3 -induced cytotoxicity. In THP-1 cells, the sensitizing effect of ethionamide on As 2 O 3 -induced cytotoxicity was highly dependent on NRF2. To our knowledge, the present study is the first to demonstrate that ethionamide suppresses NRF2–ARE signaling and disrupts the transcriptional network of the antioxidant response in AML cells, leading to sensitization to chemotherapeutic agents. - Highlights: • Identification of novel inhibitors of ARE-dependent transcription • Suppression of NRF2–ARE sensitizes THP-1 cells to chemotherapy. • Ethionamide suppresses ARE-dependent transcriptional activity. • Ethionamide and isoniazid increase the cytotoxicity of As 2 O 3 in AML cells. • Sensitization of THP-1 cells to As 2 O 3 toxicity by ethionamide is NRF2-dependent.

  3. [Relationship between sensitivity of tumor cells to chemotherapeutic agent in vivo and in vitro: experiment with mouse lymphoma cells].

    Science.gov (United States)

    Li, Chuan-gang; Li, Mo-lin; Shu, Xiao-hong; Jia, Yu-jie; Liu, Yong-ji; Li, Ming

    2007-06-12

    To study the relationship of the sensitivity of tumor cells to chemotherapeutic agent between in vivo and in vitro. Mouse lymphoma cells of the line E14 were cultured and melphalan resistant EL4 cell line (EL4/melphalan) was established by culturing EL4 cells with continuous low-concentration and intermittent gradually-increasing-concentration of melphalan in vitro. MTT assay was used to evaluate the drug sensitivity and the resistance index of the EL4/melphalan cells to melphalan was calculated. EL4/melphalan and EL4 cells of the concentration of 5 x 10(8)/L were inoculated separately into 20 C57BL/6 mice subcutaneously. 12 days later, the EL4 and EL4/melphalan tumor-bearing mice were randomly divided into 2 groups respectively, 5 mice in each group. Treatment groups were given 7.5 mg/kg melphalan intraperitoneally, and control groups were given the same volume of normal saline. The tumor size was observed every other day. Compared with the EL4 cells, the EL4/melphalan cells had no obvious changes morphologically. They could grow in RPMI 1640 medium containing 5 mg/ml melphalan. The resistance index was 2.87 against melphalan. After the treatment of melphalan of the dose 7.5 mg/kg, the tumor sizes of the treatment groups and control groups inoculated with both EL4 cells and the EL4/melphalan cells gradually decreased at the similar speed, and about one week later all tumors disappeared. However, the tumors of the control groups grew progressively and all the mice died at last. The chemotherapeutic effects of tumors in vivo have nothing to do with the effects of the chemotherapeutic agents on tumor cells in vitro. The tumor cells resistant to melphalan in vitro remain sensitive to the drug in vivo.

  4. Optimal Classes of Chemotherapeutic Agents Sensitized by Specific Small-Molecule Inhibitors of Akt In Vitro and In Vivo

    Directory of Open Access Journals (Sweden)

    Yan Shi

    2005-11-01

    Full Text Available Akt is a serine/threonine kinase that transduces survival signals from survival/growth factors. Deregulation and signal imbalance in cancer cells make them prone to apoptosis. Upregulation or activation of Akt to aid the survival of cancer cells is a common theme in human malignancies. We have developed small-molecule Akt inhibitors that are potent and specific. These Akt inhibitors can inhibit Akt activity and block phosphorylation by Akt on multiple downstream targets in cells. Synergy in apoptosis induction was observed when Akt inhibitors were combined with doxorubicin or camptothecin. Akt inhibitor-induced enhancement of topoisomerase inhibitor cytotoxicity was also evident in long-term cell survival assay. Synergy with paclitaxel in apoptosis induction was evident in cells pretreated with paclitaxel, and enhancement of tumor delay by paclitaxel was demonstrated through cotreatment with Akt inhibitor Compound A (A-443654. Combination with other classes of chemotherapeutic agents did not yield any enhancement of cytotoxicity. These findings provide important guidance in selecting appropriate classes of chemotherapeutic agents for combination with Akt inhibitors in cancer treatment.

  5. PET studies of potential chemotherapeutic agents: Pt. 10; Synthesis of ''no-carrier-added'' ( sup 11 C)-HECNU: the hydroxyethyl analog of the chemotherapeutic agent BCNU

    Energy Technology Data Exchange (ETDEWEB)

    Conway, T.; Diksic, M. (Montreal Neurological Inst. and Hospital, PQ (Canada). McConnell Brain Imaging Centre McGill Univ., Montreal, PQ (Canada). Dept. of Neurology and Neurosurgery)

    1991-01-01

    Carbon-11-labeled HECNU (1-(2-chloroethyl)-1-nitroso-3-(2-hydroxyethyl) urea) a potential chemotherapeutic agent, has been prepared by the nitrosation of the corresponding carbon-11-labeled urea, HECU, (1-(2-chloroethyl)-3-(2-hydroxyethyl) urea). The isomeric byproduct of nitrosation, 1-(2-chloroethyl)-3-nitroso-3-(2-hydroxyethyl) urea can be efficiently removed by preparative scale HPLC on a Partisil column. ({sup 11}C)-HECU was prepared by reacting ethanolamine with ({sup 11}C)-2-chloroethyl-isocyanate which was itself prepared by reacting ({sup 11}C)-phosgene with 2-chloroethylamine hydrochloride suspended in dioxane at 60-65{sup o}C. This synthesis yielded ({sup 11}C)-HECNU with an average radiochemical purity of 98% in an average radiochemical yield of 18% relative to the radioactivity measured at the end of the {sup 11}C-phosgene introduction. (author).

  6. Enterobacter and Klebsiella species isolated from fresh vegetables marketed in Valencia (Spain) and their clinically relevant resistances to chemotherapeutic agents.

    Science.gov (United States)

    Falomir, María Pilar; Rico, Hortensia; Gozalbo, Daniel

    2013-12-01

    Occurrence of antibiotic-resistant pathogenic or commensal enterobacteria in marketed agricultural foodstuffs may contribute to their incorporation into the food chain and constitutes an additional food safety concern. In this work, we have determined the clinically relevant resistances to 11 common chemotherapeutic agents in Enterobacter and Klebsiella isolates from fresh vegetables from various sources (supermarkets and greengrocers' shops in Valencia, Spain). A total of 96 isolates were obtained from 160 vegetables analyzed (50% positive samples): 68 Enterobacter isolates (59 E. cloacae, two E. aerogenes, two E. cancerogenus, one E. gergoviae, and four E. sakazakii, currently Cronobacter spp.), and 28 Klebsiella isolates (19 K. oxytoca and 9 K. pneumoniae). Only seven isolates were susceptible to all agents tested, and no resistances to ceftazidime, ciprofloxacin, gentamicin, and chloramphenicol were detected. Most isolates were resistant to amoxicillin/clavulanic acid (74 [58 Enterobacter and 16 Klebsiella]) or to ampicillin (80 [55/25]). Other resistances were less frequent: nitrofurantoin (13 isolates [12/1]), tetracycline (6 [5/1]), co-trimoxazole (3 [3/0]), cefotaxime (1 [1/0]), and streptomycin (2 [1/1]). Multiresistant isolates to two (56 [41/15]), three (10 E. cloacae isolates), four (one E. cloacae and one K. pneumoniae isolate), and five (two E. cloacae isolates) chemotherapeutic agents were also detected. The presence of potential pathogens points to marketed fresh produce, which often is eaten raw, as a risk factor for consumer health. In addition, these results support the usefulness of these bacterial species as indicators of the spreading of antibiotic resistances into the environment, particularly in the food chain, and suggest their role as carriers of resistance determinants from farms to consumers, which may constitute an additional "silent" food safety concern. Therefore, there is a need to improve the hygienic quality of marketed fresh

  7. Nanostructured nanoparticles of self-assembled lipid pro-drugs as a route to improved chemotherapeutic agents

    Energy Technology Data Exchange (ETDEWEB)

    Sagnella, Sharon M.; Gong, Xiaojuan; Moghaddam, Minoo J.; Conn, Charlotte E.; Kimpton, Kathleen; Waddington, Lynne J.; Krodkiewska, Irena; Drummond, Calum J. (CSIRO/MSE); (CSIRO/LW)

    2014-09-24

    We demonstrate that oral delivery of self-assembled nanostructured nanoparticles consisting of 5-fluorouracil (5-FU) lipid prodrugs results in a highly effective, target-activated, chemotherapeutic agent, and offers significantly enhanced efficacy over a commercially available alternative that does not self-assemble. The lipid prodrug nanoparticles have been found to significantly slow the growth of a highly aggressive mouse 4T1 breast tumour, and essentially halt the growth of a human MDA-MB-231 breast tumour in mouse xenografts. Systemic toxicity is avoided as prodrug activation requires a three-step, enzymatic conversion to 5-FU, with the third step occurring preferentially at the tumour site. Additionally, differences in the lipid prodrug chemical structure and internal nanostructure of the nanoparticle dictate the enzymatic conversion rate and can be used to control sustained release profiles. Thus, we have developed novel oral nanomedicines that combine sustained release properties with target-selective activation.

  8. Studies on uptake and distribution of chemotherapeutic agents to malignant tumors of the head and neck in rabbits, 2

    International Nuclear Information System (INIS)

    Yamada, Ryuichi

    1981-01-01

    Experiments were performed to investigate incorporation and distribution of chemotherapeutic agents into malignant tumors of the head and neck by microautoradiographic and electron microscopic-autoradiographic observations of VX2 carcinoma transplanted in the lower genial region of rabbits after injection of 3 H-Adriamycin as a tracer. The following findings were obtained. 1. On microautoradiograms, 3 H-Adriamycin was distributed predominantly in the nucleoplasm, rather than in the cytoplasm, of tumor tissues. 2. At the ultrastructural level, 3 H-Adriamycin was localized in the nuclear membrane and nucleoli within the nucleoplasm and in the rough endoplasmic reticulum and secretory granules within the cytoplasm. 3. These findings seem to indicate that Adriamycin may inhibit the synthesis of DNA and RNA in the nucleoplasm. (author)

  9. Combined Effects of Fe3O4 Nanoparticles and Chemotherapeutic Agents on Prostate Cancer Cells In Vitro

    Directory of Open Access Journals (Sweden)

    Kanako Kojima

    2018-01-01

    Full Text Available Patients with metastatic castration-resistant prostate cancer (mCRPC have poor outcomes. Docetaxel (DTX-based therapy is a current standard treatment for patients with mCRPC. Approaches combining conventional chemotherapeutic agents and nanoparticles (NPs, particularly iron oxide NPs, may overcome the serious side effects and drug resistance, resulting in the establishment of new therapeutic strategies. We previously reported the combined effects of Fe3O4 nanoparticles (Fe3O4 NPs with DTX on prostate cancer cells in vitro. In this study, we investigated the combined effects of Fe3O4 NPs and rapamycin or carboplatin on prostate cancer cells in vitro. Treatment of DU145 and PC-3 cells with Fe3O4 NPs increased intracellular reactive oxygen species (ROS levels in a concentration-dependent manner. Treatment of both cell lines with 100 μg/mL Fe3O4 NPs for 72 h resulted in significant inhibition of cell viability with a different inhibitory effect. Combination treatments with 100 µg/mL Fe3O4 NPs and 10 µM carboplatin or 10 nM rapamycin in DU145 and PC-3 cells significantly decreased cell viability. Synergistic effects on apoptosis were observed in PC-3 cells treated with Fe3O4 NPs and rapamycin and in DU145 cells with Fe3O4 NPs and carboplatin. These results suggest the possibility of combination therapy with Fe3O4 NPs and various chemotherapeutic agents as a novel therapeutic strategy for patients with mCRPC.

  10. Repurposing the FDA-approved pinworm drug pyrvinium as a novel chemotherapeutic agent for intestinal polyposis.

    Directory of Open Access Journals (Sweden)

    Bin Li

    Full Text Available Mutations in the WNT-pathway regulator ADENOMATOUS POLYPOSIS COLI (APC promote aberrant activation of the WNT pathway that is responsible for APC-associated diseases such as Familial Adenomatous Polyposis (FAP and 85% of spontaneous colorectal cancers (CRC. FAP is characterized by multiple intestinal adenomas, which inexorably result in CRC. Surprisingly, given their common occurrence, there are few effective chemotherapeutic drugs for FAP. Here we show that the FDA-approved, anti-helminthic drug Pyrvinium attenuates the growth of WNT-dependent CRC cells and does so via activation of CK1α. Furthermore, we show that Pyrvinium can function as an in vivo inhibitor of WNT-signaling and polyposis in a mouse model of FAP: APCmin mice. Oral administration of Pyrvinium, a CK1α agonist, attenuated the levels of WNT-driven biomarkers and inhibited adenoma formation in APCmin mice. Considering its well-documented safe use for treating enterobiasis in humans, our findings suggest that Pyrvinium could be repurposed for the clinical treatment of APC-associated polyposes.

  11. Suppression of NRF2–ARE activity sensitizes chemotherapeutic agent-induced cytotoxicity in human acute monocytic leukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Hui [The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States); Institute of Disease Control and Prevention, Academy of Military Medical Sciences, Beijing (China); Wang, Huihui [School of Public Health, China Medical University, 77 Puhe Road, Shenyang North New Area, Shenyang (China); Xue, Peng [The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States); Key Laboratory of the Public Health Safety, Ministry of Education, School of Public Health, Fudan University, Shanghai (China); Hou, Yongyong [School of Public Health, China Medical University, 77 Puhe Road, Shenyang North New Area, Shenyang (China); Dong, Jian [The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States); Institute of Biology and Medicine, Wuhan University of Science and Technology, Wuhan (China); Zhou, Tong [The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States); Qu, Weidong [Key Laboratory of the Public Health Safety, Ministry of Education, School of Public Health, Fudan University, Shanghai (China); Peng, Shuangqing [Institute of Disease Control and Prevention, Academy of Military Medical Sciences, Beijing (China); Li, Jin; Carmichael, Paul L. [Unilever, Safety & Environmental Assurance Centre, Colworth Science Park, Sharnbrook, Bedfordshire MK44 1LQ (United Kingdom); Nelson, Bud; Clewell, Rebecca; Zhang, Qiang; Andersen, Melvin E. [The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States); Pi, Jingbo, E-mail: jpi@mail.cmu.edu.cn [School of Public Health, China Medical University, 77 Puhe Road, Shenyang North New Area, Shenyang (China); The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC (United States)

    2016-02-01

    Nuclear factor erythroid 2-related factor 2 (NRF2), a master regulator of the antioxidant response element (ARE)-dependent transcription, plays a pivotal role in chemical detoxification in normal and tumor cells. Consistent with previous findings that NRF2–ARE contributes to chemotherapeutic resistance of cancer cells, we found that stable knockdown of NRF2 by lentiviral shRNA in human acute monocytic leukemia (AML) THP-1 cells enhanced the cytotoxicity of several chemotherapeutic agents, including arsenic trioxide (As{sub 2}O{sub 3}), etoposide and doxorubicin. Using an ARE-luciferase reporter expressed in several human and mouse cells, we identified a set of compounds, including isonicotinic acid amides, isoniazid and ethionamide, that inhibited NRF2–ARE activity. Treatment of THP-1 cells with ethionamide, for instance, significantly reduced mRNA expression of multiple ARE-driven genes under either basal or As{sub 2}O{sub 3}-challenged conditions. As determined by cell viability and cell cycle, suppression of NRF2–ARE by ethionamide also significantly enhanced susceptibility of THP-1 and U937 cells to As{sub 2}O{sub 3}-induced cytotoxicity. In THP-1 cells, the sensitizing effect of ethionamide on As{sub 2}O{sub 3}-induced cytotoxicity was highly dependent on NRF2. To our knowledge, the present study is the first to demonstrate that ethionamide suppresses NRF2–ARE signaling and disrupts the transcriptional network of the antioxidant response in AML cells, leading to sensitization to chemotherapeutic agents. - Highlights: • Identification of novel inhibitors of ARE-dependent transcription • Suppression of NRF2–ARE sensitizes THP-1 cells to chemotherapy. • Ethionamide suppresses ARE-dependent transcriptional activity. • Ethionamide and isoniazid increase the cytotoxicity of As{sub 2}O{sub 3} in AML cells. • Sensitization of THP-1 cells to As{sub 2}O{sub 3} toxicity by ethionamide is NRF2-dependent.

  12. N-cinnamoylated aminoquinolines as promising antileishmanial agents.

    Science.gov (United States)

    Vale-Costa, S; Costa-Gouveia, J; Pérez, B; Silva, T; Teixeira, C; Gomes, P; Gomes, M S

    2013-10-01

    A series of cinnamic acid conjugates of primaquine and chloroquine were evaluated for their in vitro antileishmanial activities. Although primaquine derivatives had modest activity, chloroquine conjugates exhibited potent activity against both promastigotes (50% inhibitory concentration [IC50] = 2.6 to 21.8 μM) and intramacrophagic amastigotes (IC50 = 1.2 to 9.3 μM) of Leishmania infantum. Both the high activity of these chloroquine analogues and their mild-to-low toxicity toward host cells make them promising leads for the discovery of new antileishmanial agents.

  13. Synergistic antitumor activity of oncolytic reovirus and chemotherapeutic agents in non-small cell lung cancer cells

    Directory of Open Access Journals (Sweden)

    Coffey Matthew C

    2009-07-01

    Full Text Available Abstract Background Reovirus type 3 Dearing strain (ReoT3D has an inherent propensity to preferentially infect and destroy cancer cells. The oncolytic activity of ReoT3D as a single agent has been demonstrated in vitro and in vivo against various cancers, including colon, pancreatic, ovarian and breast cancers. Its human safety and potential efficacy are currently being investigated in early clinical trials. In this study, we investigated the in vitro combination effects of ReoT3D and chemotherapeutic agents against human non-small cell lung cancer (NSCLC. Results ReoT3D alone exerted significant cytolytic activity in 7 of 9 NSCLC cell lines examined, with the 50% effective dose, defined as the initial virus dose to achieve 50% cell killing after 48 hours of infection, ranging from 1.46 ± 0.12 ~2.68 ± 0.25 (mean ± SD log10 pfu/cell. Chou-Talalay analysis of the combination of ReoT3D with cisplatin, gemcitabine, or vinblastine demonstrated strong synergistic effects on cell killing, but only in cell lines that were sensitive to these compounds. In contrast, the combination of ReoT3D and paclitaxel was invariably synergistic in all cell lines tested, regardless of their levels of sensitivity to either agent. Treatment of NSCLC cell lines with the ReoT3D-paclitaxel combination resulted in increased poly (ADP-ribose polymerase cleavage and caspase activity compared to single therapy, indicating enhanced apoptosis induction in dually treated NSCLC cells. NSCLC cells treated with the ReoT3D-paclitaxel combination showed increased proportions of mitotic and apoptotic cells, and a more pronounced level of caspase-3 activation was demonstrated in mitotically arrested cells. Conclusion These data suggest that the oncolytic activity of ReoT3D can be potentiated by taxanes and other chemotherapeutic agents, and that the ReoT3D-taxane combination most effectively achieves synergy through accelerated apoptosis triggered by prolonged mitotic arrest.

  14. Multiple repair pathways mediate tolerance to chemotherapeutic cross-linking agents in vertebrate cells.

    Science.gov (United States)

    Nojima, Kuniharu; Hochegger, Helfrid; Saberi, Alihossein; Fukushima, Toru; Kikuchi, Koji; Yoshimura, Michio; Orelli, Brian J; Bishop, Douglas K; Hirano, Seiki; Ohzeki, Mioko; Ishiai, Masamichi; Yamamoto, Kazuhiko; Takata, Minoru; Arakawa, Hiroshi; Buerstedde, Jean-Marie; Yamazoe, Mitsuyoshi; Kawamoto, Takuo; Araki, Kasumi; Takahashi, Jun A; Hashimoto, Nobuo; Takeda, Shunichi; Sonoda, Eiichiro

    2005-12-15

    Cross-linking agents that induce DNA interstrand cross-links (ICL) are widely used in anticancer chemotherapy. Yeast genetic studies show that nucleotide excision repair (NER), Rad6/Rad18-dependent postreplication repair, homologous recombination, and cell cycle checkpoint pathway are involved in ICL repair. To study the contribution of DNA damage response pathways in tolerance to cross-linking agents in vertebrates, we made a panel of gene-disrupted clones from chicken DT40 cells, each defective in a particular DNA repair or checkpoint pathway, and measured the sensitivities to cross-linking agents, including cis-diamminedichloroplatinum (II) (cisplatin), mitomycin C, and melphalan. We found that cells harboring defects in translesion DNA synthesis (TLS), Fanconi anemia complementation groups (FANC), or homologous recombination displayed marked hypersensitivity to all the cross-linking agents, whereas NER seemed to play only a minor role. This effect of replication-dependent repair pathways is distinctively different from the situation in yeast, where NER seems to play a major role in dealing with ICL. Cells deficient in Rev3, the catalytic subunit of TLS polymerase Polzeta, showed the highest sensitivity to cisplatin followed by fanc-c. Furthermore, epistasis analysis revealed that these two mutants work in the same pathway. Our genetic comprehensive study reveals a critical role for DNA repair pathways that release DNA replication block at ICLs in cellular tolerance to cross-linking agents and could be directly exploited in designing an effective chemotherapy.

  15. The clinical application of ultrasonography-guided percutaneous transhepatic injection of iodized oil containing chemotherapeutic agent for the treatment of hilar lymphatic metastasis

    International Nuclear Information System (INIS)

    Zhao Guangsheng; Zhang Yuewei; Yang Xiaohong; Li Chuang; Zhao Mu; Wang Wenqing; Wang Ruoyu

    2010-01-01

    Objective: To discuss the technique and the clinical effect of ultrasonography-guided percutaneous transhepatic injection of iodized oil containing chemotherapeutic agent for the treatment of hepatic hilar lymphatic metastasis. Methods: Under ultrasonographic guidance,percutaneous transhepatic injection of iodized oil containing chemotherapeutic agent, so-called chemo-ablation, into the diseased lymph nodes was performed in thirteen patients with hepatic hilar lymphatic metastasis. The therapeutic results were evaluated based on the post-operative imaging examinations as well as the alleviation of the clinical symptoms. Results: Percutaneous transhepatic injection of iodized oil containing chemotherapeutic agent into the diseased lymph nodes was successfully carried out in all thirteen patients. After the procedure,the patients were followed up for a mean period of 13.5 months. The therapeutic effectiveness was 100%, while the regression rate of the lesions was 76.9%. No operation-related complications occurred. Conclusion: Percutaneous transhepatic injection of iodized oil containing chemotherapeutic agent into the diseased lymph nodes under ultrasonographic guidance is an effective and safe treatment for hepatic hilar lymphatic metastasis with reliable effectiveness. (authors)

  16. Synergistic Effects of Secretory Phospholipase A2 from the Venom of Agkistrodon piscivorus piscivorus with Cancer Chemotherapeutic Agents

    Directory of Open Access Journals (Sweden)

    Jennifer Nelson

    2013-01-01

    Full Text Available Healthy cells typically resist hydrolysis catalyzed by snake venom secretory phospholipase A2. However, during various forms of programmed cell death, they become vulnerable to attack by the enzyme. This observation raises the question of whether the specificity of the enzyme for dying cells could be used as a strategy to eliminate tumor cells that have been intoxicated but not directly killed by chemotherapeutic agents. This idea was tested with S49 lymphoma cells and a broad range of antineoplastic drugs: methotrexate, daunorubicin, actinomycin D, and paclitaxel. In each case, a substantial population of treated cells was still alive yet vulnerable to attack by the enzyme. Induction of cell death by these agents also perturbed the biophysical properties of the membrane as detected by merocyanine 540 and trimethylammonium-diphenylhexatriene. These results suggest that exposure of lymphoma cells to these drugs universally causes changes to the cell membrane that render it susceptible to enzymatic attack. The data also argue that the snake venom enzyme is not only capable of clearing cell corpses but can aid in the demise of tumor cells that have initiated but not yet completed the death process.

  17. Use of the dog spleen for studying effects of irradiation and chemotherapeutic agents, with suggested uses of other organs

    International Nuclear Information System (INIS)

    Wilcox, L.D.; De Rose, G.; Cooke, D.

    1976-01-01

    The irradiation of the exteriorized spleen of the dog, with the animal lead-shielded, produced constant changes in the white blood cells. The time of recovery from the irradiation effect was determined. The normal canine spleen could handle live pneumococci injected into the splenic artery, as proven by sterile cultures of splenic vein samples. The size of the bolus used was determined by repeated trials and proved to be one billion pneumococci per pound of body weight. The capacity of the irradiated spleen to handle this number of pneumococci was impaired. It was found that whole body irradiation, nitrogen mustard, thio-tepa, cyclophosphamide, methotrexate, 5-fluorouracil, vinblastine, and azothioprine all impaired this capacity of the spleen. The dose of the chemotherapeutic agent was the same in milligrams per kilogram as that used in the cancer clinic. A method for determining the recovery time following the use of one or more agents was developed with the repeated use of the spleen model. By extending the methods used with the spleen it was found that similar use could be made, usually without surgery, of the liver, gut, and lungs

  18. Effect of mutagens, chemotherapeutic agents and defects in DNA repair genes on recombination in F' partial diploid Escherichia coli

    International Nuclear Information System (INIS)

    Norin, A.J.; Goldschmidt, E.P.

    1979-01-01

    The ability of mutagenic agents, nonmutagenic substances and defects in DNA repair to alter the genotype of F' partial diploid (F30) Escherichia coli was determined. The frequency of auxotrophic mutants and histidine requiring (His - ) haploid colonies was increased by mutagen treatment but Hfr colonies were not detected in F30 E. coli even with specific selection techniques. Genotype changes due to nonreciprocal recombination were determined by measuring the frequency of His - homogenotes, eg. F' hisC780, hisI + /hisC780, hisI + , arising from a His + heterogenote, F' hisC780 hisI + /hisC + , his1903. At least 75% of the recombinants were homozygous for histidine alleles which were present on the F' plasmid (exogenote) of the parental hetergenote rather than for histidine alleles on the chromosome. Mutagens, chemotherapeutic agents which block DNA synthesis and a defective DNA polymerase I gene, polA1, were found to increase the frequency of nonreciprocal recombination. A defect in the ability to excise thymine dimers, uvrC34, did not increase spontaneous nonreciprocal recombination. However, UV irradiation but not methyl methanesulfonate (MMS) induced greater recombination in this excision-repair defective mutant than in DNA-repair-proficient strains. (Auth.)

  19. 1 ALPHA-Hydroxyvitamin D5 as a Chemotherapeutic and Possibly Chemopreventive Agent

    Science.gov (United States)

    2004-09-01

    cancer cells. TTT TG. The primer -for the housekeeping gene G3PDH was purchased from ClonTech. The touchdown 3.2. Induction of differentiation of breast...the housekeeping gene The effects of vitamin D analogues as differentiating G3PDH (C) was identical for all the cDNAs, indicating . agents and...control housekeeping gene. "* G. Lazzaro et al. / European Journal of Cancer 36 (2000) 780-786 785 levels of VDR, do not respond to active vitamin D p53

  20. Downregulation of hPMC2 imparts chemotherapeutic sensitivity to alkylating agents in breast cancer cells.

    Science.gov (United States)

    Krishnamurthy, Nirmala; Liu, Lili; Xiong, Xiahui; Zhang, Junran; Montano, Monica M

    2015-01-01

    Triple negative breast cancer cell lines have been reported to be resistant to the cyotoxic effects of temozolomide (TMZ). We have shown previously that a novel protein, human homolog of Xenopus gene which Prevents Mitotic Catastrophe (hPMC2) has a role in the repair of estrogen-induced abasic sites. Our present study provides evidence that downregulation of hPMC2 in MDA-MB-231 and MDA-MB-468 breast cancer cells treated with temozolomide (TMZ) decreases cell survival. This increased sensitivity to TMZ is associated with an increase in number of apurinic/apyrimidinic (AP) sites in the DNA. We also show that treatment with another alkylating agent, BCNU, results in an increase in AP sites and decrease in cell survival. Quantification of western blot analyses and immunofluorescence experiments reveal that treatment of hPMC2 downregulated cells with TMZ results in an increase in γ-H2AX levels, suggesting an increase in double strand DNA breaks. The enhancement of DNA double strand breaks in TMZ treated cells upon downregulation of hPCM2 is also revealed by the comet assay. Overall, we provide evidence that downregulation of hPMC2 in breast cancer cells increases cytotoxicity of alkylating agents, representing a novel mechanism of treatment for breast cancer. Our data thus has important clinical implications in the management of breast cancer and brings forth potentially new therapeutic strategies.

  1. Increased susceptibility to chemotherapeutic alkylating agents of mice deficient in DNA repair methyltransferase.

    Science.gov (United States)

    Shiraishi, A; Sakumi, K; Sekiguchi, M

    2000-10-01

    O(6)-methylguanine-DNA methyltransferase plays vital roles in preventing induction of mutations and cancer as well as cell death related to alkylating agents. Mice defective in the MGMT: gene, encoding the methyltransferase, were used to evaluate cell death-inducing and tumorigenic activities of therapeutic agents which have alkylation potential. MGMT(-/-) mice were considerably more sensitive to dacarbazine, a monofunctional triazene, than were wild-type mice, in terms of survival. When dacarbazine was administered i.p. to 6-week-old mice and survival at 30 days was enumerated, LD(50) values of MGMT(-/-) and MGMT(+/+) mice were 20 and 450 mg/kg body wt, respectively. Increased sensitivity of MGMT(-/-) mice to 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosou rea (ACNU), a bifunctional nitrosourea, was also noted. On the other hand, there was no difference in survival of MGMT(+/+) and MGMT(-/-) mice exposed to cyclophosphamide, a bifunctional nitrogen mustard. It appears that dacarbazine and ACNU produce O(6)-alkylguanine as a major toxic lesion, while cyclophosphamide yields other types of modifications in DNA which are not subjected to the action of the methyltransferase. MGMT(-/-) mice seem to be less refractory to the tumor-inducing effect of dacarbazine than are MGMT(+/+) mice. Thus, the level of O(6)-methylguanine-DNA methyltransferase activity is an important factor when determining susceptibility to drugs with the potential for alkylation.

  2. GTP depletion synergizes the anti-proliferative activity of chemotherapeutic agents in a cell type-dependent manner

    International Nuclear Information System (INIS)

    Lin, Tao; Meng, Lingjun; Tsai, Robert Y.L.

    2011-01-01

    Highlights: → Strong synergy between mycophenolic acid (MPA) and 5-FU in MDA-MB-231 cells. → Cell type-dependent synergy between MPA and anti-proliferative agents. → The synergy of MPA on 5-FU is recapitulated by RNA polymerase-I inhibition. → The synergy of MPA on 5-FU requires the expression of nucleostemin. -- Abstract: Mycophenolic acid (MPA) depletes intracellular GTP by blocking de novo guanine nucleotide synthesis. GTP is used ubiquitously for DNA/RNA synthesis and as a signaling molecule. Here, we made a surprising discovery that the anti-proliferative activity of MPA acts synergistically with specific chemotherapeutic agents in a cell type-dependent manner. In MDA-MB-231 cells, MPA shows an extremely potent synergy with 5-FU but not with doxorubicin or etoposide. The synergy between 5-FU and MPA works most effectively against the highly tumorigenic mammary tumor cells compared to the less tumorigenic ones, and does not work in the non-breast cancer cell types that we tested, with the exception of PC3 cells. On the contrary, MPA shows the highest synergy with paclitaxel but not with 5-FU in SCC-25 cells, derived from oral squamous cell carcinomas. Mechanistically, the synergistic effect of MPA on 5-FU in MDA-MB-231 cells can be recapitulated by inhibiting the RNA polymerase-I activity and requires the expression of nucleostemin. This work reveals that the synergy between MPA and anti-proliferative agents is determined by cell type-dependent factors.

  3. The synthesis of potential chemotherapeutic agents based on leads from nature

    International Nuclear Information System (INIS)

    Brimble, M.A.

    2001-01-01

    Our research group has developed an efficient synthesis of several simpler members of pyranonaphthoquinone antibiotics using a novel annulation of a 2-acetylnaphthoquinone using 2- trimethylsilyloxyfuran to afford a furonaphthofuran ring system that then underwent oxidative rearrangement to the desired pyranonaphthoquinone ring system. This methodology was then successfully applied to the synthesis of the spiroacetal-containing pyranonaphthoquinone, griseusin A, and the C-glycosidic pyranonaphthoquinone, medermycin, which is effective against neoplastic cells in vitro, antibiotic resistant cell lines of L5178Y lymphoblastoma, and inhibits human leukaemia K 562 cells as well as platelet aggregation. The first efficient synthesis of a dimeric pyranonaphthoquinone as present in the antiviral agent, crisamycin A and γ-actinorhodin, has also been successfully effected using an efficient double furofuran-oxidative rearrangement strategy starting from a bis(2-acetyl-1,4-naphthoquinone)

  4. HFE polymorphisms influence the response to chemotherapeutic agents via induction of p16INK4A.

    Science.gov (United States)

    Lee, Sang Y; Liu, Siying; Mitchell, Ryan M; Slagle-Webb, Becky; Hong, Young-Soo; Sheehan, Jonas M; Connor, James R

    2011-11-01

    HFE is a protein that impacts cellular iron uptake. HFE gene variants are identified as risk factors or modifiers for multiple diseases. Using HFE stably transfected human neuroblastoma cells, we found that cells carrying the C282Y HFE variant do not differentiate when exposed to retinoic acid. Therefore, we hypothesized HFE variants would impact response to therapeutic agents. Both the human neuroblastoma and glioma cells that express the C282Y HFE variant are resistant to Temodar, geldanamycin and γ-radiation. A gene array analysis revealed that p16INK4A (p16) expression was increased in association with C282Y expression. Decreasing p16 protein by siRNA resulted in increased vulnerability to all of the therapeutic agents suggesting that p16 is responsible for the resistance. Decreasing HFE expression by siRNA resulted in a 85% decrease in p16 expression in the neuroblastoma cells but not the astrocytoma cells. These data suggest a potential direct relationship between HFE and p16 that may be cell specific or mediated by different pathways in the different cell types. In conclusion, the C282Y HFE variant impacts the vulnerability of cancer cells to current treatment strategies apparently by increasing expression of p16. Although best known as a tumor suppressor, there are multiple reports that p16 is elevated in some forms of cancer. Given the frequency of the HFE gene variants, as high as 10% of the Caucasian population, these data provide compelling evidence that the C282Y HFE variant should be part of a pharmacogenetic strategy for evaluating treatment efficacy in cancer cells. Copyright © 2011 UICC.

  5. [Ebola hemorrhagic fever: Properties of the pathogen and development of vaccines and chemotherapeutic agents].

    Science.gov (United States)

    Kiselev, O I; Vasin, A V; Shevyryova, M P; Deeva, E G; Sivak, K V; Egorov, V V; Tsvetkov, V B; Egorov, A Yu; Romanovskaya-Romanko, E A; Stepanova, L A; Komissarov, A B; Tsybalova, L M; Ignatjev, G M

    2015-01-01

    Ebola hemorrhagic fever (EHF) epidemic currently ongoing in West Africa is not the first among numerous epidemics in the continent. Yet it seems to be the worst EHF epidemic outbreak caused by Ebola virus Zaire since 1976 as regards its extremely large scale and rapid spread in the population. Experiments to study the agent have continued for more than 20 years. The EHF virus has a relatively simple genome with seven genes and additional reading frame resulting from RNA editing. While being of a relatively low genetic capacity, the virus can be ranked as a standard for pathogenicity with the ability to evade the host immune response in uttermost perfection. The EHF virus has similarities with retroviruses, but belongs to (-)RNA viruses of a nonretroviral origin. Genetic elements of the virus, NIRV, were detected in animal and human genomes. EHF virus glycoprotein (GP) is a class I fusion protein and shows more similarities than distinctions in tertiary structure with SIV and HIV gp41 proteins and even influenza virus hemagglutinin. EHF is an unusual infectious disease, and studying the molecular basis of its pathogenesis may contribute to new findings in therapy of severe conditions leading to a fatal outcome.

  6. Novel amidines and analogues as promising agents against intracellular parasites: a systematic review.

    Science.gov (United States)

    Soeiro, M N C; Werbovetz, K; Boykin, D W; Wilson, W D; Wang, M Z; Hemphill, A

    2013-07-01

    Parasitic protozoa comprise diverse aetiological agents responsible for important diseases in humans and animals including sleeping sickness, Chagas disease, leishmaniasis, malaria, toxoplasmosis and others. They are major causes of mortality and morbidity in tropical and subtropical countries, and are also responsible for important economic losses. However, up to now, for most of these parasitic diseases, effective vaccines are lacking and the approved chemotherapeutic compounds present high toxicity, increasing resistance, limited efficacy and require long periods of treatment. Many of these parasitic illnesses predominantly affect low-income populations of developing countries for which new pharmaceutical alternatives are urgently needed. Thus, very low research funding is available. Amidine-containing compounds such as pentamidine are DNA minor groove binders with a broad spectrum of activities against human and veterinary pathogens. Due to their promising microbicidal activity but their rather poor bioavailability and high toxicity, many analogues and derivatives, including pro-drugs, have been synthesized and screened in vitro and in vivo in order to improve their selectivity and pharmacological properties. This review summarizes the knowledge on amidines and analogues with respect to their synthesis, pharmacological profile, mechanistic and biological effects upon a range of intracellular protozoan parasites. The bulk of these data may contribute to the future design and structure optimization of new aromatic dicationic compounds as novel antiparasitic drug candidates.

  7. Modification of in vitro and in vivo BCG cell wall-induced immunosuppression by treatment with chemotherapeutic agents or indomethacin

    International Nuclear Information System (INIS)

    DeSilva, M.A.; Wepsic, H.T.; Mizushima, Y.; Nikcevich, D.A.; Larson, C.H.

    1985-01-01

    The in vitro inhibition of spleen cell blastogenesis response and the in vivo enhancement of tumor growth are phenomena associated with BCG cell wall (BCGcw) immunization. What effect treatment with chemotherapeutic agents and the prostaglandin inhibitor indomethacin would have on the in vitro and in vivo responses to BCGcw immunization was evaluated. In vitro blastogenesis studies showed that chemotherapy pretreatment prior to immunization with BCGcw resulted in a restoration of the spleen cell blastogenesis response. In blastogenesis addback studies, where BCGcw-induced irradiated splenic suppressor cells were admixed with normal cells, less inhibition of blastogenesis occurred when spleen cells were obtained from rats that had received the combined treatment of chemotherapy and BCGcw immunization versus only BCGcw immunization. The cocultivation of spleen cells from BCGcw-immunized rats with indomethacin resulted in a 30-40% restoration of the blastogenesis response. In vivo studies showed that BCGcw-mediated enhancement of intramuscular tumor growth of the 3924a ACI rat tumor could be abrogated by either pretreatment with busulfan or mitomycin or by the feeding of indomethacin

  8. 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.

  9. Validation and use of microdialysis for determination of pharmacokinetic properties of the chemotherapeutic agent mitomycin C - an experimental study

    International Nuclear Information System (INIS)

    Sørensen, Olaf; Andersen, Anders; Olsen, Harald; Alexandr, Kristian; Ekstrøm, Per Olaf; Giercksky, Karl-Erik; Flatmark, Kjersti

    2010-01-01

    Mitomycin C is a chemotherapeutic agent used in the treatment of peritoneal surface malignancies, administered as hyperthermic intraperitoneal chemotherapy after cytoreductive surgery. Pharmacokinetic studies have been based on analyses of blood, urine and abdominal perfusate, but actual tissue concentrations of the drug have never been determined. Microdialysis is an established method for continuous monitoring of low-molecular substances in tissues, and in the present study microdialysis of mitomycin C was studied in vitro and in vivo. Using in vitro microdialysis, relative recovery was determined when varying drug concentration, temperature and perfusion flow rate. In vivo microdialysis was performed in rats to verify long-term stability of relative recovery in four compartments (vein, peritoneum, extraperitoneal space and hind leg muscle). Subsequently, intravenous and intraperitoneal bolus infusion experiments were performed and pharmacokinetic parameters were calculated. In vitro, compatibility of mitomycin C and microdialysis equipment was demonstrated, and relative recovery was stable over an adequate concentration range, moderately increased by raising medium temperature and increased when flow rate was reduced, all according to theory. In vivo, stable relative recovery was observed over seven hours. Mitomycin C exhibited fast and even distribution in rat tissues, and equal bioavailability was achieved by intravenous and intraperitoneal infusion. The half-life of mitomycin C calculated after intravenous infusion was 40 minutes. Mitomycin C concentration can be reliable monitored in vivo using microdialysis, suggesting that this technique can be used in pharmacokinetic studies of this drug during hyperthermic intraperitoneal chemotherapy

  10. Tumor vascular-targeted co-delivery of anti-angiogenesis and chemotherapeutic agents by mesoporous silica nanoparticle-based drug delivery system for synergetic therapy of tumor

    Directory of Open Access Journals (Sweden)

    Li X

    2015-12-01

    Full Text Available Xiaoyu Li, Meiying Wu, Limin Pan, Jianlin Shi State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, People’s Republic of China Abstract: To overcome the drawback of drug non-selectivity in traditional chemotherapy, the construction of multifunctional targeting drug delivery systems is one of the most effective and prevailing approaches. The intratumoral anti-angiogenesis and the tumor cell-killing are two basic approaches in fighting tumors. Herein we report a novel tumor vascular-targeting multidrug delivery system using mesoporous silica nanoparticles as carrier to co-load an antiangiogenic agent (combretastatin A4 and a chemotherapeutic drug (doxorubicin and conjugate with targeting molecules (iRGD peptide for combined anti-angiogenesis and chemotherapy. Such a dual-loaded drug delivery system is capable of delivering the two agents at tumor vasculature and then within tumors through a differentiated drug release strategy, which consequently results in greatly improved antitumor efficacy at a very low doxorubicin dose of 1.5 mg/kg. The fast release of the antiangiogenic agent at tumor vasculatures led to the disruption of vascular structure and had a synergetic effect with the chemotherapeutic drug slowly released in the following delivery of chemotherapeutic drug into tumors. Keywords: mesoporous silica nanoparticles, drug delivery, tumor vasculatures targeting, antiangiogenic agent

  11. Promising oncolytic agents for metastatic breast cancer treatment

    Directory of Open Access Journals (Sweden)

    Cody JJ

    2015-06-01

    Full Text Available James J Cody,1 Douglas R Hurst2 1ImQuest BioSciences, Frederick, MD, 2Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA Abstract: New therapies for metastatic breast cancer patients are urgently needed. The long-term survival rates remain unacceptably low for patients with recurrent disease or disseminated metastases. In addition, existing therapies often cause a variety of debilitating side effects that severely impact quality of life. Oncolytic viruses constitute a developing therapeutic modality in which interest continues to build due to their ability to spare normal tissue while selectively destroying tumor cells. A number of different viruses have been used to develop oncolytic agents for breast cancer, including herpes simplex virus, adenovirus, vaccinia virus, measles virus, reovirus, and others. In general, clinical trials for several cancers have demonstrated excellent safety records and evidence of efficacy. However, the impressive tumor responses often observed in preclinical studies have yet to be realized in the clinic. In order for the promise of oncolytic virotherapy to be fully realized for breast cancer patients, effectiveness must be demonstrated in metastatic disease. This review provides a summary of oncolytic virotherapy strategies being developed to target metastatic breast cancer. Keywords: oncolytic virus, virotherapy, breast cancer, metastasis 

  12. Reações tegumentares adversas relacionadas aos agentes antineoplásicos: parte II Adverse mucocutaneous reactions related to chemotherapeutic agents: part II

    Directory of Open Access Journals (Sweden)

    Paulo Ricardo Criado

    2010-10-01

    Full Text Available Os eventos e reações envolvendo quimioterapia são frequentes na prática oncológica. Agentes quimioterápicos são uma modalidade de tratamento amplamente utilizada. Efeitos colaterais podem variar de frequência e também ser confundidos com outras manifestações tegumentares do tratamento oncológico. Este artigo objetiva expor as informações sobre reações cutâneas à quimioterapia, em especial, aqueles para os quais o dermatologista é requisitado a emitir parecer e a comentar sobre a segurança e a viabilidade da readministração de uma droga específica. Os autores descrevem os aspectos associados a esses eventos, fazendo uma análise detalhada de cada um deles.Events and reactions involving chemotherapy are common in clinical oncology. Chemotherapeutic agents are widely used in therapy. Side effects range from the common to the rare and may be confused with other mucocutaneous manifestations resulting from the oncological treatment. The objective of this paper was to present data on skin reactions to chemotherapy, particularly those cases in which the dermatologist is requested to issue a report and asked to comment on the safety and viability of readministration of a specific drug. The authors describe aspects associated with these events, presenting a detailed analysis of each one of them.

  13. Environmental and chemotherapeutic agents induce breakage at genes involved in leukemia-causing gene rearrangements in human hematopoietic stem/progenitor cells

    Energy Technology Data Exchange (ETDEWEB)

    Thys, Ryan G., E-mail: rthys@wakehealth.edu [Department of Cancer Biology, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157-1016 (United States); Lehman, Christine E., E-mail: clehman@wakehealth.edu [Department of Cancer Biology, Wake Forest School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157-1016 (United States); Pierce, Levi C.T., E-mail: Levipierce@gmail.com [Human Longevity, Inc., San Diego, California 92121 (United States); Wang, Yuh-Hwa, E-mail: yw4b@virginia.edu [Department of Biochemistry and Molecular Genetics, University of Virginia, 1340 Jefferson Park Avenue, Charlottesville, VA 22908-0733 (United States)

    2015-09-15

    Highlights: • Environmental/chemotherapeutic agents cause DNA breakage in MLL and CBFB in HSPCs. • Diethylnitrosamine-induced DNA breakage at MLL and CBFB shown for the first time. • Chemical-induced DNA breakage occurs at topoisomerase II cleavage sites. • Chemical-induced DNA breaks display a pattern similar to those in leukemia patients. • Long-term exposures suggested to generate DNA breakage at leukemia-related genes. - Abstract: Hematopoietic stem and progenitor cells (HSPCs) give rise to all of the cells that make up the hematopoietic system in the human body, making their stability and resilience especially important. Damage to these cells can severely impact cell development and has the potential to cause diseases, such as leukemia. Leukemia-causing chromosomal rearrangements have largely been studied in the context of radiation exposure and are formed by a multi-step process, including an initial DNA breakage and fusion of the free DNA ends. However, the mechanism for DNA breakage in patients without previous radiation exposure is unclear. Here, we investigate the role of non-cytotoxic levels of environmental factors, benzene, and diethylnitrosamine (DEN), and chemotherapeutic agents, etoposide, and doxorubicin, in generating DNA breakage at the patient breakpoint hotspots of the MLL and CBFB genes in human HSPCs. These conditions represent exposure to chemicals encountered daily or residual doses from chemotherapeutic drugs. Exposure of HSPCs to non-cytotoxic levels of environmental chemicals or chemotherapeutic agents causes DNA breakage at preferential sites in the human genome, including the leukemia-related genes MLL and CBFB. Though benzene, etoposide, and doxorubicin have previously been linked to leukemia formation, this is the first study to demonstrate a role for DEN in the generation of DNA breakage at leukemia-specific sites. These chemical-induced DNA breakpoints coincide with sites of predicted topoisomerase II cleavage. The

  14. Environmental and chemotherapeutic agents induce breakage at genes involved in leukemia-causing gene rearrangements in human hematopoietic stem/progenitor cells

    International Nuclear Information System (INIS)

    Thys, Ryan G.; Lehman, Christine E.; Pierce, Levi C.T.; Wang, Yuh-Hwa

    2015-01-01

    Highlights: • Environmental/chemotherapeutic agents cause DNA breakage in MLL and CBFB in HSPCs. • Diethylnitrosamine-induced DNA breakage at MLL and CBFB shown for the first time. • Chemical-induced DNA breakage occurs at topoisomerase II cleavage sites. • Chemical-induced DNA breaks display a pattern similar to those in leukemia patients. • Long-term exposures suggested to generate DNA breakage at leukemia-related genes. - Abstract: Hematopoietic stem and progenitor cells (HSPCs) give rise to all of the cells that make up the hematopoietic system in the human body, making their stability and resilience especially important. Damage to these cells can severely impact cell development and has the potential to cause diseases, such as leukemia. Leukemia-causing chromosomal rearrangements have largely been studied in the context of radiation exposure and are formed by a multi-step process, including an initial DNA breakage and fusion of the free DNA ends. However, the mechanism for DNA breakage in patients without previous radiation exposure is unclear. Here, we investigate the role of non-cytotoxic levels of environmental factors, benzene, and diethylnitrosamine (DEN), and chemotherapeutic agents, etoposide, and doxorubicin, in generating DNA breakage at the patient breakpoint hotspots of the MLL and CBFB genes in human HSPCs. These conditions represent exposure to chemicals encountered daily or residual doses from chemotherapeutic drugs. Exposure of HSPCs to non-cytotoxic levels of environmental chemicals or chemotherapeutic agents causes DNA breakage at preferential sites in the human genome, including the leukemia-related genes MLL and CBFB. Though benzene, etoposide, and doxorubicin have previously been linked to leukemia formation, this is the first study to demonstrate a role for DEN in the generation of DNA breakage at leukemia-specific sites. These chemical-induced DNA breakpoints coincide with sites of predicted topoisomerase II cleavage. The

  15. A rapid method for testing in vivo the susceptibility of different strains of Trypanosoma cruzi to active chemotherapeutic agents

    Directory of Open Access Journals (Sweden)

    Leny S. Filardi

    1984-06-01

    Full Text Available A method is described which permits to determine in vivo an in a short period of time (4-6 hours the sensitivity of T. cruzo strains to known active chemotherapeutic agents. By using resistant- and sensitive T. cruzi stains a fairly good correlation was observed between the results obtained with this rapid method (which detects activity against the circulating blood forms and those obtained with long-term schedules which involve drug adminstration for at least 20 consecutive days and a prolonged period of assessment. This method may be used to characterize susceptibility to active drugs used clinically, provide infomation on the specific action against circulating trypomastigotes and screen active compounds. Differences in the natural susceptibility of Trypanosoma cruzi strains to active drugs have been already reported using different criteria, mostly demanding long-term study of the animal (Hauschka, 1949; Bock, Gonnert & Haberkorn, 1969; Brener, Costa & Chiari, 1976; Andrade & Figueira, 1977; Schlemper, 1982. In this paper we report a method which detects in 4-6 hours the effect of drugs on bloodstream forms in mice with established T. cruzi infections. The results obtained with this method show a fairly good correlation with those obtained by prolonged treatment schedules used to assess the action of drugs in experimental Chagas' disease and may be used to study the sensitivity of T. cruzi strains to active drugs.No presente trabalho descreve-se um metodo que permite determinar in vivo e em curto espaço de tempo (4-6 horas a sensibilidade de cepas de T. cruzi a agentes terapeuticos ativos na doença de Chagas. Usando-se cepas sensíveis e resistentes aos medicamentos foi possível observar uma boa correlação entre os resultados obtidos com o método rápido (que detecta atividade contra as formas circulantes do parasita e aqueles obtidos com esquema de acao prolongada que envolve a administração da droga por 20 dias e posterior avalia

  16. Effects of repeated administration of chemotherapeutic agents tamoxifen, methotrexate, and 5-fluorouracil on the acquisition and retention of a learned response in mice

    Science.gov (United States)

    Foley, John J.; Clark-Vetri, Rachel; Raffa, Robert B.

    2011-01-01

    Rationale A number of cancer chemotherapeutic agents have been associated with a loss of memory in breast cancer patients although little is known of the causality of this effect. Objectives To assess the potential cognitive effects of repeated exposure to chemotherapeutic agents, we administered the selective estrogen receptor modulator tamoxifen or the antimetabolite chemotherapy, methotrexate, and 5-fluorouracil, alone and in combination to mice and tested them in a learning and memory assay. Methods Swiss-Webster male mice were injected with saline, 32 mg/kg tamoxifen, 3.2 or 32 mg/kg methotrexate, 75 mg/kg 5-fluorouracil, 3.2 or 32 mg/kg methotrexate in combination with 75 mg/kg 5-fluorouracil once per week for 3 weeks. On days 23 and 24, mice were tested for acquisition and retention of a nose-poke response in a learning procedure called autoshaping. In addition, the acute effects of tamoxifen were assessed in additional mice in a similar procedure. Results The chemotherapeutic agents alone and in combination reduced body weight relative to saline treatment over the course of 4 weeks. Repeated treatment with tamoxifen produced both acquisition and retention effects relative to the saline-treated group although acute tamoxifen was without effect except at a behaviorally toxic dose. Repeated treatment with methotrexate in combination with 5-fluorouracil produced effects on retention, but the magnitude of these changes depended on the methotrexate dose. Conclusions These data demonstrate that repeated administration of tamoxifen or certain combination of methotrexate and 5-fluorouracil may produce deficits in the acquisition or retention of learned responses which suggest potential strategies for prevention or remediation might be considered in vulnerable patient populations. PMID:21537942

  17. 1,3-Bis(2-chloroethyl)-1-nitrosourea-loaded bovine serum albumin nanoparticles with dual magnetic resonance-fluorescence imaging for tracking of chemotherapeutic agents.

    Science.gov (United States)

    Wei, Kuo-Chen; Lin, Feng-Wei; Huang, Chiung-Yin; Ma, Chen-Chi M; Chen, Ju-Yu; Feng, Li-Ying; Yang, Hung-Wei

    To date, knowing how to identify the location of chemotherapeutic agents in the human body after injection is still a challenge. Therefore, it is urgent to develop a drug delivery system with molecular imaging tracking ability to accurately understand the distribution, location, and concentration of a drug in living organisms. In this study, we developed bovine serum albumin (BSA)-based nanoparticles (NPs) with dual magnetic resonance (MR) and fluorescence imaging modalities (fluorescein isothiocyanate [FITC]-BSA-Gd/1,3-bis(2-chloroethyl)-1-nitrosourea [BCNU] NPs) to deliver BCNU for inhibition of brain tumor cells (MBR 261-2). These BSA-based NPs are water dispersible, stable, and biocompatible as confirmed by XTT cell viability assay. In vitro phantoms and in vivo MR and fluorescence imaging experiments show that the developed FITC-BSA-Gd/BCNU NPs enable dual MR and fluorescence imaging for monitoring cellular uptake and distribution in tumors. The T1 relaxivity (R1) of FITC-BSA-Gd/BCNU NPs was 3.25 mM(-1) s(-1), which was similar to that of the commercial T1 contrast agent (R1 =3.36 mM(-1) s(-1)). The results indicate that this multifunctional drug delivery system has potential bioimaging tracking of chemotherapeutic agents ability in vitro and in vivo for cancer therapy.

  18. Antibody mimetics: promising complementary agents to animal-sourced antibodies.

    Science.gov (United States)

    Baloch, Abdul Rasheed; Baloch, Abdul Wahid; Sutton, Brian J; Zhang, Xiaoying

    2016-01-01

    Despite their wide use as therapeutic, diagnostic and detection agents, the limitations of polyclonal and monoclonal antibodies have inspired scientists to design the next generation biomedical agents, so-called antibody mimetics that offer many advantages over conventional antibodies. Antibody mimetics can be constructed by protein-directed evolution or fusion of complementarity-determining regions through intervening framework regions. Substantial progress in exploiting human, butterfly (Pieris brassicae) and bacterial systems to design and select mimetics using display technologies has been made in the past 10 years, and one of these mimetics [Kalbitor® (Dyax)] has made its way to market. Many challenges lie ahead to develop mimetics for various biomedical applications, especially those for which conventional antibodies are ineffective, and this review describes the current characteristics, construction and applications of antibody mimetics compared to animal-sourced antibodies. The possible limitations of mimetics and future perspectives are also discussed.

  19. Modified Gadonanotubes as a Promising Novel MRI Contrasting Agent

    OpenAIRE

    Rouzbeh Jahanbakhsh; Fatemeh Atyabi; Saeed Shanehsazzadeh; Zahra Sobhani; Mohsen Adeli; Rassoul Dinarvand

    2013-01-01

    Background and purpose of the study Carbon nanotubes (CNTs) are emerging drug and imaging carrier systems which show significant versatility. One of the extraordinary characteristics of CNTs as Magnetic Resonance Imaging (MRI) contrasting agent is the extremely large proton relaxivities when loaded with gadolinium ion (Gdn 3+) clusters. Methods In this study equated Gdn 3+ clusters were loaded in the sidewall defects of oxidized multiwalled (MW) CNTs. The amount of loaded gadolinium ion into ...

  20. Deoxypodophyllotoxin: a promising therapeutic agent from herbal medicine.

    Science.gov (United States)

    Khaled, Meyada; Jiang, Zhen-Zhou; Zhang, Lu-Yong

    2013-08-26

    Recently, biologically active compounds isolated from plants used in herbal medicine have been the center of interest. Deoxypodophyllotoxin (DPT), structurally closely related to the lignan podophyllotoxin, is a potent antitumor and anti-inflammatory agent. However, DPT has not been used clinically yet. Also, DPT from natural sources seems to be unavailable. Hence, it is important to establish alternative resources for the production of such lignan; especially that it is used as a precursor for the semi-synthesis of the cytostatic drugs etoposide phosphate and teniposide. The update paper provides an overview of DPT as an effective anticancer natural compound and a leader for cytotoxic drugs synthesis and development in order to highlight the gaps in our knowledge and explore future research needs. The present review covers the literature available from 1877 to 2012. The information was collected via electronic search using Chinese papers and the major scientific databases including PubMed, Sciencedirect, Web of Science and Google Scholar using the keywords. All abstracts and full-text articles reporting database on the history and current status of DPT were gathered and analyzed. Plants containing DPT have played an important role in traditional medicine. In light of the in vitro pharmacological investigations, DPT is a high valuable medicinal agent that has anti-tumor, anti-proliferative, anti-inflammatory and anti-allergic properties. Further, DPT is an important precursor for the cytotoxic aryltetralin lignan, podophyllotoxin, which is used to obtain semisynthetic derivatives like etoposide and teniposide used in cancer therapy. However, most studies have focused on the in vitro data. Therefore, DPT has not been used clinically yet. DPT has emerged as a potent chemical agent from herbal medicine. Therefore, in vivo studies are needed to carry out clinical trials in humans and enable the development of new anti-cancer agents. In addition, DPT from commercial

  1. Effect of time intervals between irradiation and chemotherapeutic agents on the normal tissue damage. Comparison between in vivo and in vitro experiments

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hisao; Nakayama, Toshitake; Hashimoto, Shozo (Keio Univ., Tokyo (Japan). School of Medicine)

    1989-05-01

    Experiments have been carried out to determine the effect on the cell survivals at different time intervals between irradiation and chemotherapeutic agents (BLM, cisDDP, ADM and ACNU) in either the in vivo or the in vitro system. The intestinal epithelial assay was applied on the in vivo system. The clonogenic cell survivals of V/sub 79/ cells, both in the proliferative and the plateau phases, were determined in the in vitro system. The V/sub 79/ cells in the plateau phase were more sensitive to BLM, cisDDP and ACNU than those in the proliferative phase, however, the result was reverse with ADM. When BLM, cisDDP or ACNU was combined with irradiation at different time intervals, the response of the plateau phase V/sub 79/ cells to combination therapies were very similar to those of the intestinal epithelial cells. On the other hand, V/sub 79/ cells in the proliferative phase, which were treated with ADM and irradiation, showed the similar response as the intestinal cells. These results suggest that studies of chemo-radiotherapy with cultured cells which are sensitive to chemotherapeutic agents might be suitable to expect the in vivo damage of the normal tissue. (author).

  2. Alkanediamide-Linked Bisbenzamidines Are Promising Antiparasitic Agents

    Directory of Open Access Journals (Sweden)

    Jean J. Vanden Eynde

    2016-04-01

    Full Text Available A series of 15 alkanediamide-linked bisbenzamidines and related analogs was synthesized and tested in vitro against two Trypanosoma brucei (T.b. subspecies: T.b. brucei and T.b. rhodesiense, Trypanosoma cruzi, Leishmania donovani and two Plasmodium falciparum subspecies: a chloroquine-sensitive strain (NF54 and a chloroquine-resistant strain (K1. The in vitro cytotoxicity was determined against rat myoblast cells (L6. Seven compounds (5, 6, 10, 11, 12, 14, 15 showed high potency against both strains of T. brucei and P. falciparum with the inhibitory concentrations for 50% (IC50 in the nanomolar range (IC50 = 1–96 nM. None of the tested derivatives was significantly active against T. cruzi or L. donovani. Three of the more potent compounds (5, 6, 11 were evaluated in vivo in mice infected with the drug-sensitive (Lab 110 EATRO and KETRI 2002 or drug-resistant (KETRI 2538 and KETRI 1992 clinical isolates of T. brucei. Compounds 5 and 6 were highly effective in curing mice infected with the drug-sensitive strains, including a drug-resistant strain KETRI 2538, but were ineffective against KETRI 1992. Thermal melting of DNA and molecular modeling studies indicate AT-rich DNA sequences as possible binding sites for these compounds. Several of the tested compounds are suitable leads for the development of improved antiparasitic agents.

  3. TTFields alone and in combination with chemotherapeutic agents effectively reduce the viability of MDR cell sub-lines that over-express ABC transporters

    International Nuclear Information System (INIS)

    Schneiderman, Rosa S; Shmueli, Esther; Kirson, Eilon D; Palti, Yoram

    2010-01-01

    Exposure of cancer cells to chemotherapeutic agents may result in reduced sensitivity to structurally unrelated agents, a phenomenon known as multidrug resistance, MDR. The purpose of this study is to investigate cell growth inhibition of wild type and the corresponding MDR cells by Tumor Treating Fields - TTFields, a new cancer treatment modality that is free of systemic toxicity. The TTFields were applied alone and in combination with paclitaxel and doxorubicin. Three pairs of wild type/MDR cell lines, having resistivity resulting from over-expression of ABC transporters, were studied: a clonal derivative (C11) of parental Chinese hamster ovary AA8 cells and their emetine-resistant sub-line Emt R1 ; human breast cancer cells MCF-7 and their mitoxantrone-resistant sub lines MCF-7/Mx and human breast cancer cells MDA-MB-231 and their doxorubicin resistant MDA-MB-231/Dox cells. TTFields were applied for 72 hours with and without the chemotherapeutic agents. The numbers of viable cells in the treated cultures and the untreated control groups were determined using the XTT assay. Student t-test was applied to asses the significance of the differences between results obtained for each of the three cell pairs. TTFields caused a similar reduction in the number of viable cells of wild type and MDR cells. Treatments by TTFields/drug combinations resulted in a similar increased reduction in cell survival of wild type and MDR cells. TTFields had no effect on intracellular doxorubicin accumulation in both wild type and MDR cells. The results indicate that TTFields alone and in combination with paclitaxel and doxorubicin effectively reduce the viability of both wild type and MDR cell sub-lines and thus can potentially be used as an effective treatment of drug resistant tumors

  4. 1,3-Bis(2-chloroethyl-1-nitrosourea-loaded bovine serum albumin nanoparticles with dual magnetic resonance–fluorescence imaging for tracking of chemotherapeutic agents

    Directory of Open Access Journals (Sweden)

    Wei KC

    2016-08-01

    Full Text Available Kuo-Chen Wei,1 Feng-Wei Lin,2 Chiung-Yin Huang,1 Chen-Chi M Ma,3 Ju-Yu Chen,1 Li-Ying Feng,1 Hung-Wei Yang2 1Department of Neurosurgery, Chang Gung Memorial Hospital, School of Medicine, Chang Gung University, Taoyuan, 2Institute of Medical Science and Technology, National Sun Yat-sen University, Kaohsiung, 3Department of Chemical Engineering, National Tsing Hua University, Hsinchu, Taiwan, Republic of China Abstract: To date, knowing how to identify the location of chemotherapeutic agents in the human body after injection is still a challenge. Therefore, it is urgent to develop a drug delivery system with molecular imaging tracking ability to accurately understand the distribution, location, and concentration of a drug in living organisms. In this study, we developed bovine serum albumin (BSA-based nanoparticles (NPs with dual magnetic resonance (MR and fluorescence imaging modalities (fluorescein isothiocyanate [FITC]-BSA-Gd/1,3-bis(2-chloroethyl-1-nitrosourea [BCNU] NPs to deliver BCNU for inhibition of brain tumor cells (MBR 261-2. These BSA-based NPs are water dispersible, stable, and biocompatible as confirmed by XTT cell viability assay. In vitro phantoms and in vivo MR and fluorescence imaging experiments show that the developed FITC-BSA-Gd/BCNU NPs enable dual MR and fluorescence imaging for monitoring cellular uptake and distribution in tumors. The T1 relaxivity (R1 of FITC-BSA-Gd/BCNU NPs was 3.25 mM-1 s-1, which was similar to that of the commercial T1 contrast agent (R1 =3.36 mM-1 s-1. The results indicate that this multifunctional drug delivery system has potential bioimaging tracking of chemotherapeutic agents ability in vitro and in vivo for cancer therapy. Keywords: drug tracking, fluorescence imaging, MR imaging, BSA nanoparticles, cancer therapy

  5. Diethylglyoxal bis(guanylhydrazone): a novel highly potent inhibitor of S-adenosylmethionine decarboxylase with promising properties for potential chemotherapeutic use.

    Science.gov (United States)

    Elo, H; Mutikainen, I; Alhonen-Hongisto, L; Laine, R; Jänne, J

    1988-07-01

    Diethylglyoxal bis(guanylhydrazone) (DEGBG), a novel analog of the antileukemic agent methylglyoxal bis(guanylhydrazone) (MGBG) was synthesized. It was found to be the most powerful inhibitor of yeast S-adenosylmethionine decarboxylase (AdoMetDC) so far studied (Ki approx. 9 nM). This property, together with the finding that the compound is a weaker inhibitor of intestinal diamine oxidase than are MGBG and its glyoxal, ethylglyoxal and ethylmethylglyoxal analogs, makes the compound a promising candidate as a polyamine antimetabolite for chemotherapy studies. DEGBG was also found to potentiate the antiproliferative effect of the ornithine decarboxylase inhibitor alpha-difluoromethyl ornithine against mouse L1210 leukemia cells in vitro. DEGBG increased several-fold the intracellular putrescine concentration of cultured L1210 cells, just as MGBG and its ethylglyoxal analog are known to do. The results strongly suggest that DEGBG is worth further studies. Combined with previous studies, they also made possible the construction of some empirical rules concerning the structure-activity relationships of bis(guanylhydrazone) type inhibitors of AdoMetDC. The identity of DEGBG was confirmed by a single-crystal X-ray analysis and by 1H- and 13C-NMR spectroscopy. It consisted of the same isomer as MGBG and several of its analogs are known to consist of.

  6. Studies on uptake and distribution of chemotherapeutic agents to malignant tumors of the head and neck in rabbits, 2. /sup 3/H-Adriamycin

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, R. (Gifu Univ. (Japan). Faculty of Medicine)

    1981-09-01

    Experiments were performed to investigate incorporation and distribution of chemotherapeutic agents into malignant tumors of the head and neck by microautoradiographic and electron microscopic-autoradiographic observations of VX2 carcinoma transplanted in the lower genial region of rabbits after injection of /sup 3/H-Adriamycin as a tracer. The following findings were obtained. 1. On microautoradiograms, /sup 3/H-Adriamycin was distributed predominantly in the nucleoplasm, rather than in the cytoplasm, of tumor tissues. 2. At the ultrastructural level, /sup 3/H-Adriamycin was localized in the nuclear membrane and nucleoli within the nucleoplasm and in the rough endoplasmic reticulum and secretory granules within the cytoplasm. 3. These findings seem to indicate that Adriamycin may inhibit the synthesis of DNA and RNA in the nucleoplasm.

  7. Utilization of a selective tumour artery catheterization technique for the intra-arterial delivery of chemotherapeutic agents and radiopharmaceuticals in a combined chemotherapy-radiotherapy clinical research programme

    International Nuclear Information System (INIS)

    Wiley, A.L. Jr.; Wirtanen, G.W.; Holden, J.E.; Polcyn, R.E.

    1977-01-01

    Combined intra-arterial chemotherapeutic agents (principally actinomycin-D) and radiation therapy has been utilized in the treatment of 35 patients with massive unresectable malignancies. The goals may be separated into three distinct categories. An attempt has been made to convert unresectable malignancies to surgical resectability, to provide a definitive therapy for massive tumours in patients who either refuse surgery or are not surgery candidates, and to provide palliation. Twelve of 15 initially unresectable tumours treated with actinomycin-D became surgically resectable (no resection was attempted in the other four because they either developed metastasis during therapy or did not complete the therapy), 4 of 6 massive tumours treated definitively have remained locally controlled from 18 to 108 months, and 7 of 9 patients treated palliatively were significantly benefited by the therapy. Impressive responses were also achieved in several patients treated with intra-arterial 5-fluorouracil and 5-iodo-2'-deoxyuridine. The authors therefore consider combined, concurrent radiation therapy and intra-arterially administered chemotherapeutic agents worthy of further clinical investigation as a means of treating massive malignancies. They also suggest that the best chance of optimizing the therapeutic ratio of such therapy is dependent primarily on a proper understanding of clinical tumour vascularity and of its subsequent effect on drug and oxygen distributions within the radiation treatment volume. Accordingly, tumour vascularity has been clinically evaluated by the use of intra-arterially administered radiopharmaceuticals. Such clinical data, in conjunction with radiobiological data, might in the future be utilized to optimize both low and high LET combined therapy by allowing for correction of the physical isodose for drug and oxygen concentration variations. (author)

  8. Nitric oxide donors attenuate clongenic potential in rat C6 glioma cells treated with alkylating chemotherapeutic agents.

    Science.gov (United States)

    Yang, Jir-Jei; Yin, Jiu-Haw; Yang, Ding-I

    2007-05-11

    1,3-Bis(2-chloroethyl)-1-nitrosourea (BCNU) kills tumor cells via multiple actions including alkylation and carbamoylation. Previously, we have reported that formation of S-nitrosoglutathione (GSNO) in glioma cells overexpressing inducible nitric oxide synthase (iNOS) contributed to nitric oxide (NO)-dependent carbamoylating chemoresistance against BCNU. To further characterize the effects of NO on alkylating cytotoxicity, colony formation assay was applied to evaluate the effects of various NO donors on rat C6 glioma cells challenged with alkylating agents. We demonstrate that NO donors including GSNO, diethylamine NONOate (DEA/NO), and sodium nitroprusside (SNP) substantially reduced the extent of colony formation in glioma cells treated with alkylating agents, namely methyl methanesulfonate (MMS), N-methyl-N-nitrosourea (MNU), and N-ethyl-N-nitrosourea (ENU). Without alkylating agents these NO-releasing agents alone had no effects on clongenic potential of rat C6 glioma cells. Among these three NO donors used, the effectiveness in potentiating alkylating cytotoxicity is in the order of "GSNO>DEA/NO>SNP" when applied at the same dosages. GSNO also exerted similar synergistic actions reducing the extents of colony formation when co-administrated with 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)-hydrazine (compound #1), another alkylating agent that mimics the chloroethylating action of BCNU. Together with our previous findings, we propose that NO donors may be used as adjunct chemotherapy with alkylating agents for such malignant brain tumors as glioblastoma multiforme (GBM). In contrast, production of NO as a result of iNOS induction, such as that occurring after surgical resection of brain tumors, may compromise the efficacy of carbamoylating chemotherapy.

  9. Design, synthesis, molecular docking and biological evaluation of new dithiocarbamates substituted benzimidazole and chalcones as possible chemotherapeutic agents.

    Science.gov (United States)

    Bacharaju, Keerthana; Jambula, Swathi Reddy; Sivan, Sreekanth; Jyostnatangeda, Saritha; Manga, Vijjulatha

    2012-05-01

    A series of novel dithiocarbamates with benzimidazole and chalcone scaffold have been designed synthesised and evaluated for their antimitotic activity. Compounds 4c and 9d display the most promising antimitotic activity with IC(50) of 1.66 μM and 1.52 μM respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. FANCD2 re-expression is associated with glioma grade and chemical inhibition of the Fanconi Anaemia pathway sensitises gliomas to chemotherapeutic agents

    Science.gov (United States)

    Patil, Abhijit A.; Sayal, Parag; Depondt, Marie-Lise; Beveridge, Ryan D.; Roylance, Anthony; Kriplani, Deepti H.; Myers, Katie N.; Cox, Angela; Jellinek, David; Fernando, Malee; Carroll, Thomas A.; Collis, Spencer J.

    2014-01-01

    Brain tumours kill more children and adults under 40 than any other cancer. Around half of primary brain tumours are glioblastoma multiforme (GBMs) where treatment remains a significant challenge. GBM survival rates have improved little over the last 40 years, thus highlighting an unmet need for the identification/development of novel therapeutic targets and agents to improve GBM treatment. Using archived and fresh glioma tissue, we show that in contrast to normal brain or benign schwannomas GBMs exhibit re-expression of FANCD2, a key protein of the Fanconi Anaemia (FA) DNA repair pathway, and possess an active FA pathway. Importantly, FANCD2 expression levels are strongly associated with tumour grade, revealing a potential exploitable therapeutic window to allow inhibition of the FA pathway in tumour cells, whilst sparing normal brain tissue. Using several small molecule inhibitors of the FA pathway in combination with isogenic FA-proficient/deficient glioma cell lines as well as primary GBM cultures, we demonstrate that inhibition of the FA pathway sensitises gliomas to the chemotherapeutic agents Temozolomide and Carmustine. Our findings therefore provide a strong rationale for the development of novel and potent inhibitors of the FA pathway to improve the treatment of GBMs, which may ultimately impact on patient outcome. PMID:25071006

  11. Characterization of the response of a human breast carcinoma cell line (T-47D) to radiation and chemotherapeutic agents

    International Nuclear Information System (INIS)

    Prager, A.; Ben-Hur, E.; Riklis, E.

    1981-01-01

    The response of a human breast carcinoma cell line (T-47D) to various antitumour agents, gamma irradiation, UV light and heat was studied, using the colony-forming ability technique. Combinations of radiation with drugs and heat were also tested. The resulting survival curves corresponded to one of five patterns: simple exponential, biphasic exponential, threshold exponential, exponential plateau and ineffectual. Whereas the cells were particularly sensitive to gamma irradiation, the response to UV light was normal. The patient from whom this cell line originated did not respond to METHOTREXATEsup(R) therapy. The in vitro results correlated with this observation. (author)

  12. A robust and rapid xenograft model to assess efficacy of chemotherapeutic agents for human acute myeloid leukemia

    International Nuclear Information System (INIS)

    Saland, E; Boutzen, H; Castellano, R; Pouyet, L; Griessinger, E; Larrue, C; Toni, F de; Scotland, S; David, M; Danet-Desnoyers, G; Vergez, F; Barreira, Y; Collette, Y; Récher, C; Sarry, J-E

    2015-01-01

    Relevant preclinical mouse models are crucial to screen new therapeutic agents for acute myeloid leukemia (AML). Current in vivo models based on the use of patient samples are not easy to establish and manipulate in the laboratory. Our objective was to develop robust xenograft models of human AML using well-characterized cell lines as a more accessible and faster alternative to those incorporating the use of patient-derived AML cells. Five widely used AML cell lines representing various AML subtypes were transplanted and expanded into highly immunodeficient non-obese diabetic/LtSz-severe combined immunodeficiency IL2Rγ c null mice (for example, cell line-derived xenografts). We show here that bone marrow sublethal conditioning with busulfan or irradiation has equal efficiency for the xenotransplantation of AML cell lines. Although higher number of injected AML cells did not change tumor engraftment in bone marrow and spleen, it significantly reduced the overall survival in mice for all tested AML cell lines. On the basis of AML cell characteristics, these models also exhibited a broad range of overall mouse survival, engraftment, tissue infiltration and aggressiveness. Thus, we have established a robust, rapid and straightforward in vivo model based on engraftment behavior of AML cell lines, all vital prerequisites for testing new therapeutic agents in preclinical studies

  13. Mitochondrial targeting of human O6-methylguanine DNA methyltransferase protects against cell killing by chemotherapeutic alkylating agents.

    Science.gov (United States)

    Cai, Shanbao; Xu, Yi; Cooper, Ryan J; Ferkowicz, Michael J; Hartwell, Jennifer R; Pollok, Karen E; Kelley, Mark R

    2005-04-15

    DNA repair capacity of eukaryotic cells has been studied extensively in recent years. Mammalian cells have been engineered to overexpress recombinant nuclear DNA repair proteins from ectopic genes to assess the impact of increased DNA repair capacity on genome stability. This approach has been used in this study to specifically target O(6)-methylguanine DNA methyltransferase (MGMT) to the mitochondria and examine its impact on cell survival after exposure to DNA alkylating agents. Survival of human hematopoietic cell lines and primary hematopoietic CD34(+) committed progenitor cells was monitored because the baseline repair capacity for alkylation-induced DNA damage is typically low due to insufficient expression of MGMT. Increased DNA repair capacity was observed when K562 cells were transfected with nuclear-targeted MGMT (nucl-MGMT) or mitochondrial-targeted MGMT (mito-MGMT). Furthermore, overexpression of mito-MGMT provided greater resistance to cell killing by 1,3-bis (2-chloroethyl)-1-nitrosourea (BCNU) than overexpression of nucl-MGMT. Simultaneous overexpression of mito-MGMT and nucl-MGMT did not enhance the resistance provided by mito-MGMT alone. Overexpression of either mito-MGMT or nucl-MGMT also conferred a similar level of resistance to methyl methanesulfonate (MMS) and temozolomide (TMZ) but simultaneous overexpression in both cellular compartments was neither additive nor synergistic. When human CD34(+) cells were infected with oncoretroviral vectors that targeted O(6)-benzylguanine (6BG)-resistant MGMT (MGMT(P140K)) to the nucleus or the mitochondria, committed progenitors derived from infected cells were resistant to 6BG/BCNU or 6BG/TMZ. These studies indicate that mitochondrial or nuclear targeting of MGMT protects hematopoietic cells against cell killing by BCNU, TMZ, and MMS, which is consistent with the possibility that mitochondrial DNA damage and nuclear DNA damage contribute equally to alkylating agent-induced cell killing during chemotherapy.

  14. An intron splice acceptor polymorphism in hMSH2 and risk of leukemia after treatment with chemotherapeutic alkylating agents.

    Science.gov (United States)

    Worrillow, Lisa J; Travis, Lois B; Smith, Alexandra G; Rollinson, Sara; Smith, Andrew J; Wild, Christopher P; Holowaty, Eric J; Kohler, Betsy A; Wiklund, Tom; Pukkala, Eero; Roman, Eve; Morgan, Gareth J; Allan, James M

    2003-08-01

    We sought to determine whether the -6 exon 13 T>C polymorphism in the DNA mismatch repair gene hMSH2 modulates susceptibility to acute myeloid leukemia after therapy and particularly after O(6)-guanine alkylating chemotherapy. We also determined the extent of microsatellite instability (MSI) in therapy-related acute myeloid leukemia (t-AML) as a marker of dysfunctional DNA mismatch repair. Using a novel restriction fragment length polymorphism, verified by direct sequencing, we have genotyped 91 t-AML cases, 420 de novo acute myeloid leukemia cases, and 837 controls for the hMSH2 -6 exon 13 polymorphism. MSI was evaluated in presentation bone marrow from 34 cases using the mononucleotide microsatellite markers BAT16, BAT25, and BAT26. Distribution of the hMSH2 -6 exon 13 polymorphism was not significantly different between de novo acute myeloid leukemia cases and controls, with heterozygotes and homozygotes for the variant (C) allele representing 12.2 and 1.6%, respectively, of the control population. However, the variant (C) hMSH2 allele was significantly overrepresented in t-AML cases that had previously been treated with O(6)-guanine alkylating agents, including cyclophosphamide and procarbazine, compared with controls (odds ratio, 4.02; 95% confidence interval, 1.40-11.37). Thirteen of 34 (38%) t-AML cases were MSI positive, and 2 of these 13 cases were homozygous for the variant (C) allele, a frequency substantially higher than in the control population. Association of the hMSH2 -6 exon 13 variant (C) allele with leukemia after O(6)-guanine alkylating agents implicates this allele in conferring a nondisabling DNA mismatch repair defect with concomitant moderate alkylation tolerance, which predisposes to the development of t-AML via the induction of DNA mismatch repair-disabling mutations and high-grade MSI. Homozygosity for the hMSH2 variant in 2 of 13 MSI-positive t-AML cases provides some support for this model.

  15. Reaction of a chemotherapeutic agent, 6-mercaptopurine, with a direct-acting, electrophilic carcinogen, benzo[a]pyrene-7,8-diol 9,10-epoxide.

    Science.gov (United States)

    MacLeod, M C; Stewart, E; Daylong, A; Lew, L K; Evans, F E

    1991-01-01

    The chemotherapeutic agent 6-mercaptopurine (6-MP) has been shown to react covalently with the ultimate carcinogenic metabolite of benzo[a]pyrene, 7-r,8-t-dihydroxy-9-t,10-t-oxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE), in aqueous solution, forming a single adduct. NMR studies of the HPLC-purified product were consistent with its identification as 10(S)-(6'-mercaptopurinyl)-7,8,9-trihydroxy-7,8,9,10- tetrahydrobenzo[a]pyrene. Reaction kinetics were analyzed by using both HPLC separation of the products formed and a spectrophotometric assay for adduct formation. A simple model in which direct reaction between 6-MP and BPDE takes place without formation of a physical complex was found to adequately predict the dependence of product ratios on 6-MP concentration. Variations in the observed rate constant for this reaction with changes in temperature, pH, and buffer concentration were determined and compared to the effects of these variables on the observed rate constant for BPDE hydrolysis. In each case, the processes were affected quite differently, suggesting that different rate-determining steps are involved. The data suggest that the reaction mechanism involves SN2 attack of the anion of 6-MP, formed by ionization of the sulfhydryl group, on carbon 10 of BPDE, resulting in a trans-9,10 reaction product.

  16. Study of enteroparasites infection frequency and chemotherapeutic agents used in pediatric patients in a community living in Porto Alegre, RS, Brazil

    Directory of Open Access Journals (Sweden)

    Morrone Fernanda B.

    2004-01-01

    Full Text Available Parasitic infections caused by intestinal protozoan and helminths affect more than two billion people worldwide and chemotherapy is the most commonly used therapeutic procedure. Considering the problems created by parasitic infections and the incorrect use of drugs, the aim of this work was to detect the frequency of enteroparasites infection and to estimate the use of chemotherapeutic agents in children living in the periphery of the city of Porto Alegre, RS, Brazil. Ninety-six preschool age children, who had parasitological exams and who used antiparasitic drugs, were analyzed. The efficacy of treatment was evaluated by stool examination repeated six months after treatment. The same diagnostic test was used to evaluate parasitological cure, which was defined as absence of eggs and cysts in the stool. From these children, 79 (82.3% were contaminated by some species of parasite, the most prevalent were Ascaris lumbricoides, Trichuris trichiura and Giardia lamblia. The most commonly used drugs were mebendazole (86% of prescriptions and metronidazole (30.3%. The cure rate in the 79 children, examined 6 months after treatment, was 65.3% for A. lumbricoides and 66.1% for T. trichiura. This study suggests that a continuous education program regarding the prevention and treatment of parasitic infections is an essential tool for their eradication.

  17. Low-density lipoprotein as a potential vehicle for chemotherapeutic agents and radionucleotides in the management of gynecologic neoplasms

    International Nuclear Information System (INIS)

    Gal, D.; Ohashi, M.; MacDonald, P.C.; Buchsbaum, H.J.; Simpson, E.R.

    1981-01-01

    Cholesterol metabolism was studied in cells from two established gynecologic cancer cell lines which were maintained in monolayer cultures. The cell lines were derived and established from poorly differentiated epidermoid cervical carcinoma (EC-50) and endometrial adenocarcinoma (AC-258). The specific activity of 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase, the rate-limiting enzyme of cholesterol de novo synthesis, in AC-258 cells (1700 pmoles x mg-1 microsomal protein x min-1) was three times higher than that found in EC-50 cells (550 pmoles x mg-1 microsomal protein x min-1). However, epidermoid cervical cancer cells (EC-50) metabolized low-density lipoprotein (LDL), the major transport vehicle for cholesterol in plasma, at a very high rate (14,000 ng x mg-1 cell protein x 6 hours). This rate is fifteen times greater than the rate observed in fetal adrenal tissue and fifty times greater than the rate observed in nonneoplastic gynecologic tissue, each in organ culture. Both cancer cells (EC-50 and AC-258) in monolayer culture were shown to have specific receptors for LDL. These cancer cells demonstrate no defect in LDL metabolism, and lysosomal degradation of LDL was blocked by chloroquine. From the results of studies of specific binding of LDL in tissues obtained from nude mice it was demonstrated that membrane fractions prepared from EC-50 cells, after propagation in the mice, contained fifteen to thirty times more specific binding capacity for [125I]iodo-LDL than vital organs of the mouse, such as the liver, heart, lung, kidney, or brain. The results of these studies are suggestive that certain tumor cells might have a higher affinity for LDL than normal tissues and cytotoxic drugs or radionucleotides ligated to the LDL macromolecule may be utilized for the specific delivery of these agents

  18. Low-density lipoprotein as a potential vehicle for chemotherapeutic agents and radionucleotides in the management of gynecologic neoplasms

    International Nuclear Information System (INIS)

    Gal, D.; Ohashi, M.; MacDonald, P.C.; Buchsbaum, H.J.; Simpson, E.R.

    1981-01-01

    Cholesterol metabolism was studied in cells from two established gynecologic cancer cell lines which were maintained in monolayer cultures. The cell lines were derived and established from poorly differentiated epidermoid cervical carcinoma and endometrial adenocarcinoma. The specific activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase, the rate-limiting enzyme of cholesterol de novo synthesis, in AC-258 cells was three times higher than that found in EC-50 cells. However, epidermoid cervical cancer cells metabolized low-density lipoprotein, the major transport vehicle for cholesterol in plasma, at a very high rate. This rate is fifteen times greater than the rate observed in fetal adrenal tissue and fifty times greater than the rate observed in nonneoplastic gynecologic tissue, each in organ culture. Both cancer cells in monolayer culture were shown to have specific receptors for LDL. These cancer cells demonstrate no defect in LDL metabolism, and lysosomal degradation of LDL was blocked by chloroquine. From the results of studies of specific binding of LDL in tissues obtained from nude mice it was demonstrated that membrane fractions prepared from EC-50 cells, after propagation in the mice, contained fifteen to thirty times more specific binding capacity for [125I]iodo-LDL than vital organs of the mouse, such as the liver, heart, lung, kidney, or brain. The results of these studies are suggestive that certain tumor cells might have a higher affinity for LDL than normal tissues and cytotoxic drugs or radionucleotides ligated to the LDL macromolecule may be utilized for the specific delivery of these agents

  19. Inhibition of phosphatidylinositol 3-kinase promotes tumor cell resistance to chemotherapeutic agents via a mechanism involving delay in cell cycle progression

    International Nuclear Information System (INIS)

    McDonald, Gail T.; Sullivan, Richard; Pare, Genevieve C.; Graham, Charles H.

    2010-01-01

    Approaches to overcome chemoresistance in cancer cells have involved targeting specific signaling pathways such as the phosphatidylinositol 3-kinase (PI3K) pathway, a stress response pathway known to be involved in the regulation of cell survival, apoptosis and growth. The present study determined the effect of PI3K inhibition on the clonogenic survival of human cancer cells following exposure to various chemotherapeutic agents. Treatment with the PI3K inhibitors LY294002 or Compound 15e resulted in increased survival of MDA-MB-231 breast carcinoma cells after exposure to doxorubicin, etoposide, 5-fluorouracil, and vincristine. Increased survival following PI3K inhibition was also observed in DU-145 prostate, HCT-116 colon and A-549 lung carcinoma cell lines exposed to doxorubicin. Increased cell survival mediated by LY294002 was correlated with a decrease in cell proliferation, which was linked to an increase in the proportion of cells in the G 1 phase of the cell cycle. Inhibition of PI3K signaling also resulted in higher levels of the cyclin-dependent kinase inhibitors p21 Waf1/Cip1 and p27 Kip1 ; and knockdown of p27 kip1 with siRNA attenuated resistance to doxorubicin in cells treated with LY294002. Incubation in the presence of LY294002 after exposure to doxorubicin resulted in decreased cell survival. These findings provide evidence that PI3K inhibition leads to chemoresistance in human cancer cells by causing a delay in cell cycle; however, the timing of PI3K inhibition (either before or after exposure to anti-cancer agents) may be a critical determinant of chemosensitivity.

  20. African indigenous plants with chemotherapeutic potentials and ...

    African Journals Online (AJOL)

    Herbal-based and plant-derived products can be exploited with sustainable comparative and competitive advantage. This review presents some indigenous African plants with chemotherapeutic properties and possible ways of developing them into potent pharmacological agents using biotechnological approaches.

  1. Heterocyclic N-oxides - A Promising Class of Agents Against Tuberculosis, Malaria and Neglected Tropical Diseases.

    Science.gov (United States)

    Dos Santos Fernandes, Guilherme Felipe; Pavan, Aline Renata; Dos Santos, Jean Leandro

    2018-04-17

    Heterocyclic N-oxides have emerged as promising agents against a number of diseases and disorders, especially infectious diseases. This review analyzes the emergence and development of this scaffold in the medicinal chemistry, focusing mainly on the discovery of new heterocyclic N-oxide compounds with potent activity against tuberculosis, malaria and neglected tropical diseases (i.e. leishmaniasis and Chagas disease). A number of heterocyclic N-oxide are described herein, nevertheless, the following chemical classes deserve to be highlighted due to the large number of reports in the literature about their promising pharmacological effects: furoxan, benzofuroxan, quinoxaline 1,4-di-N-oxide, indolone N-oxide and benzimidazole N-oxide. In order to describe those most promising compounds, we included in this review only those most biologically active heterocyclic N-oxide published since 2000. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  2. Oxidative metabolism of monensin in rat liver microsomes and interactions with tiamulin and other chemotherapeutic agents: evidence for the involvement of cytochrome P-450 3A subfamily.

    Science.gov (United States)

    Nebbia, C; Ceppa, L; Dacasto, M; Carletti, M; Nachtmann, C

    1999-09-01

    Monensin (MON) is an ionophore antibiotic widely used in veterinary practice as a coccidiostatic or a growth promoter. The aims of this study were to characterize the P-450 isoenzyme(s) involved in the biotransformation of the ionophore and to investigate how this process may be affected by tiamulin and other chemotherapeutic agents known to produce toxic interactions with MON when administered concurrently in vivo. In liver microsomes from untreated rats (UT) or from rats pretreated, respectively, with ethanol (ETOH), beta-naphthoflavone (betaNAF), phenobarbital (PB), pregnenolone 16alpha-carbonitrile (PCN), or dexamethasone (DEX), the rate of MON O-demethylation was the following: DEX > PCN > PB > UT = ETOH > betaNAF; similar results were obtained by measuring total MON metabolism. In addition, the extent of triacetyloleandomycin-mediated P-450 complexes was greatly reduced by the prior addition of 100 microM MON. In DEX-treated microsomes, MON O-demethylation was found to fit monophasic Michaelis-Menten kinetics (K(M) = 67.6 +/- 0.01 microM; V(max) = 4.75 +/- 0.76 nmol/min/mg protein). Tiamulin markedly inhibited this activity in an apparent competitive manner, with a calculated K(i) (Dixon plot) of 8.2 microM and an IC(50) of about 25 microM. At the latter concentration, only ketoconazole or metyrapone, which can bind P-450 3A, inhibited MON O-demethylase to a greater extent than tiamulin, whereas alpha-naphthoflavone, chloramphenicol, or sulphametasine was less effective. These results suggest that P-450 3A plays an important role in the oxidative metabolism of MON and that compounds capable of binding or inhibiting this isoenzyme could be expected to give rise to toxic interactions with the ionophore.

  3. Nanospheric Chemotherapeutic and Chemoprotective Agents

    Science.gov (United States)

    2008-09-01

    Rutgers scientists led by Prof. Joachim Kohn and TyRx Pharma, Inc., announced the FDA’s clearance of a new medical device for hernia repair that...significant decrease of the cell metabolic activity of KB cervical carcinoma cells was detected, confirming that these nanospheres do not induce any short...term cytotoxicity. Cell viability was analyzed by MTS colorimetric assay after 3 days. Figure 11: Metabolic activity of KB cervical carcinoma cells

  4. Chemotherapeutic agents attenuate CXCL12-mediated migration of colon cancer cells by selecting for CXCR4-negative cells and increasing peptidase CD26

    International Nuclear Information System (INIS)

    Cutler, Murray J.; Lowthers, Erica L.; Richard, Cynthia L.; Hajducek, Dagmar M.; Spagnuolo, Paul A.; Blay, Jonathan

    2015-01-01

    Recurrence of colorectal cancer (CRC) may arise due to the persistence of drug-resistant and cancer-initiating cells that survive exposure to chemotherapy. Proteins responsible for this recurrence include the chemokine receptor CXCR4, which is known to enable CRC metastasis, as well as the cancer-initiating cell marker and peptidase CD26, which terminates activity of its chemokine CXCL12. We evaluated the expression and function of CXCR4 and CD26 in colon cancer cell lines and xenografts following treatment with common chemotherapies using radioligand binding, flow cytometry, immunofluorescence, and enzymatic assays. 5-Fluorouracil, oxaliplatin and SN-38 (the active metabolite of irinotecan), as well as cisplatin, methotrexate and vinblastine, each caused decreases in cell-surface CXCR4 and concomitant increases in CD26 on HT-29, T84, HRT-18, SW480 and SW620 CRC cell lines. Flow cytometry indicated that the decline in CXCR4 was associated with a significant loss of CXCR4+/CD26- cells. Elevations in CD26 were paralleled by increases in both the intrinsic dipeptidyl peptidase activity of CD26 as well as its capacity to bind extracellular adenosine deaminase. Orthotopic HT-29 xenografts treated with standard CRC chemotherapeutics 5-fluorouracil, irinotecan, or oxaliplatin showed dramatic increases in CD26 compared to untreated tumors. Consistent with the loss of CXCR4 and gain in CD26, migratory responses to exogenous CXCL12 were eliminated in cells pretreated with cytotoxic agents, although cells retained basal motility. Analysis of cancer-initiating cell CD44 and CD133 subsets revealed drug-dependent responses of CD26/CD44/CD133 populations, suggesting that the benefits of combining standard chemotherapies 5-fluoruracil and oxaliplatin may be derived from their complementary elimination of cell populations. Our results indicate that conventional anticancer agents may act to inhibit chemokine-mediated migration through eradication of CXCR4+ cells and attenuation of

  5. Reactivating p53 and Inducing Tumor Apoptosis (RITA) Enhances the Response of RITA-Sensitive Colorectal Cancer Cells to Chemotherapeutic Agents 5-Fluorouracil and Oxaliplatin.

    Science.gov (United States)

    Wiegering, Armin; Matthes, Niels; Mühling, Bettina; Koospal, Monika; Quenzer, Anne; Peter, Stephanie; Germer, Christoph-Thomas; Linnebacher, Michael; Otto, Christoph

    2017-04-01

    oxaliplatin to enhance the antiproliferative response to both chemotherapeutic agents. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  6. Reactivating p53 and Inducing Tumor Apoptosis (RITA Enhances the Response of RITA-Sensitive Colorectal Cancer Cells to Chemotherapeutic Agents 5-Fluorouracil and Oxaliplatin

    Directory of Open Access Journals (Sweden)

    Armin Wiegering

    2017-04-01

    of RITA-sensitive CRC cells within both panels of established CRC cell lines and primary patient-derived CRC cell lines (6/14 that provide a rationale for combining RITA with 5FU or oxaliplatin to enhance the antiproliferative response to both chemotherapeutic agents.

  7. CYB5D2 requires heme-binding to regulate HeLa cell growth and confer survival from chemotherapeutic agents.

    Directory of Open Access Journals (Sweden)

    Anthony Bruce

    Full Text Available The cytochrome b5 domain containing 2 (CYB5D2; Neuferricin protein has been reported to bind heme, however, the critical residues responsible for heme-binding are undefined. Furthermore, the relationship between heme-binding and CYB5D2-mediated intracellular functions remains unknown. Previous studies examining heme-binding in two cytochrome b5 heme-binding domain-containing proteins, damage-associated protein 1 (Dap1; Saccharomyces cerevisiae and human progesterone receptor membrane component 1 (PGRMC1, have revealed that conserved tyrosine (Y 73, Y79, aspartic acid (D 86, and Y127 residues present in human CYB5D2 may be involved in heme-binding. CYB5D2 binds to type b heme, however, only the substitution of glycine (G at D86 (D86G within its cytochrome b5 heme-binding (cyt-b5 domain abolished its heme-binding ability. Both CYB5D2 and CYB5D2(D86G localize to the endoplasmic reticulum. Ectopic CYB5D2 expression inhibited cell proliferation and anchorage-independent colony growth of HeLa cells. Conversely, CYB5D2 knockdown and ectopic CYB5D2(D86G expression increased cell proliferation and colony growth. As PGRMC1 has been reported to regulate the expression and activities of cytochrome P450 proteins (CYPs, we examined the role of CYB5D2 in regulating the activities of CYPs involved in sterol synthesis (CYP51A1 and drug metabolism (CYP3A4. CYB5D2 co-localizes with cytochrome P450 reductase (CYPOR, while CYB5D2 knockdown reduced lanosterol demethylase (CYP51A1 levels and rendered HeLa cells sensitive to mevalonate. Additionally, knockdown of CYB5D2 reduced CYP3A4 activity. Lastly, CYB5D2 expression conferred HeLa cell survival from chemotherapeutic agents (paclitaxel, cisplatin and doxorubicin, with its ability to promote survival being dependent on its heme-binding ability. Taken together, this study provides evidence that heme-binding is critical for CYB5D2 in regulating HeLa cell growth and survival, with endogenous CYB5D2 being required to

  8. Computational enzymology for degradation of chemical warfare agents: promising technologies for remediation processes

    Directory of Open Access Journals (Sweden)

    2017-03-01

    Full Text Available Chemical weapons are a major worldwide problem, since they are inexpensive, easy to produce on a large scale and difficult to detect and control. Among the chemical warfare agents, we can highlight the organophosphorus compounds (OP, which contain the phosphorus element and that have a large number of applications. They affect the central nervous system and can lead to death, so there are a lot of works in order to design new effective antidotes for the intoxication caused by them. The standard treatment includes the use of an anticholinergic combined to a central nervous system depressor and an oxime. Oximes are compounds that reactivate Acetylcholinesterase (AChE, a regulatory enzyme responsible for the transmission of nerve impulses, which is one of the molecular targets most vulnerable to neurotoxic agents. Increasingly, enzymatic treatment becomes a promising alternative; therefore, other enzymes have been studied for the OP degradation function, such as phosphotriesterase (PTE from bacteria, human serum paraoxonase 1 (HssPON1 and diisopropyl fluorophosphatase (DFPase that showed significant performances in OP detoxification. The understanding of mechanisms by which enzymes act is of extreme importance for the projection of antidotes for warfare agents, and computational chemistry comes to aid and reduce the time and costs of the process. Molecular Docking, Molecular Dynamics and QM/MM (quantum-mechanics/molecular-mechanics are techniques used to investigate the molecular interactions between ligands and proteins.

  9. Chemotherapeutic targets in parasites: contemporary strategies

    National Research Council Canada - National Science Library

    Mansour, Tag E; Mansour, Joan MacKinnon

    2002-01-01

    ... identify effective antiparasitic agents. An introduction to the early development of parasite chemotherapy is followed by an overview of biophysical techniques and genomic and proteomic analyses. Several chapters are devoted to specific types of chemotherapeutic agents and their targets in malaria, trypanosomes, leishmania, and amitochondrial...

  10. Nanostructured lipid carriers employing polyphenols as promising anticancer agents: Quality by design (QbD) approach.

    Science.gov (United States)

    Bhise, Ketki; Kashaw, Sushil Kumar; Sau, Samaresh; Iyer, Arun K

    2017-06-30

    Cancer is one of the leading causes of death worldwide. There are several hurdles in cancer therapy because of side-effects which limits its usage. Nanoparticulate drug delivery systems have been tested against cancer in a range of scientific studies. In the recent years, advanced research on Nanostructured Lipid Carriers (NLCs) has garnered considerable attention owing to the advantages over their first-generation counterparts, Solid Lipid Nanoparticles (SLN). NLCs facilitate efficient loading of poorly water soluble drugs with simple methods of drug loading. Recently, there is an increased interest in polyphenols because of the evidence of their promising role in prevention of cancer. Polyphenols are produced as secondary metabolites by plants. Their role in prevention of development of tumors through variety of mechanisms and reduction of tumor cell mass has been reported. This article aims to review the science behind development of NLCs and role of polyphenols as promising anticancer agents. Principles of Quality by Design (QbD) have also been explained which are used in formulation-development of many nanoparticles, including NLCs, as reported in literature. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Metal oxide nanoparticles as antimicrobial agents: a promise for the future.

    Science.gov (United States)

    Raghunath, Azhwar; Perumal, Ekambaram

    2017-02-01

    Microbial infectious diseases are a global threat to human health. Excess and improper use of antibiotics has created antimicrobial-resistant microbes that can defy clinical treatment. The hunt for safe and alternate antimicrobial agents is on in order to overcome such resistant micro-organisms, and the birth of nanotechnology offers promise to combat infectious organisms. Over the past two decades, metal oxide nanoparticles (MeO-NPs) have become an attractive alternative source to combat microbes that are highly resistant to various classes of antibiotics. Their vast array of physicochemical properties enables MeO-NPs to act as antimicrobial agents through various mechanisms. Apart from exhibiting antimicrobial properties, MeO-NPs also serve as carriers of drugs, thus barely providing a chance for micro-organisms to develop resistance. These immense multiple properties exhibited by MeO-NPs will have an impact on the treatment of deadly infectious diseases. This review discusses the mechanisms of action of MeO-NPs against micro-organisms, safety concerns, challenges and future perspectives. Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

  12. A Review of Promising Natural Chemopreventive Agents for Head and Neck Cancer.

    Science.gov (United States)

    Crooker, Kyle; Aliani, Rana; Ananth, Megha; Arnold, Levi; Anant, Shrikant; Thomas, Sufi Mary

    2018-03-30

    Head and neck squamous cell carcinoma (HNSCC) accounts for 300,000 deaths per year worldwide and overall survival rates have shown little improvement over the past three decades. Current treatment methods including surgery, chemotherapy, and radiotherapy leave patients with secondary morbidities. Thus, treatment of HNSCC may benefit from exploration of natural compounds as chemopreventive agents. With excellent safety profiles, reduced toxicities, antioxidant properties, and general acceptance for use as dietary supplements, natural compounds are viewed as a desirable area of investigation for chemoprevention. Though most of the field is early in development, numerous studies display the potential utility of natural compounds against HNSCC. These compounds face additional challenges such as low bioavailability for systemic delivery, potential toxicities when consumed in pharmacological doses, and acquired resistance. However, novel delivery vehicles and synthetic analogs have shown overcome some of these challenges. This review covers eleven promising natural compounds in the chemoprevention of HNSCC including vitamin A, curcumin, isothiocyanate, green tea, luteolin, resveratrol, genistein, lycopene, bitter melon, withaferin A, and guggulsterone. The review discusses the therapeutic potential and associated challenges of these agents in the chemopreventive efforts against HNSCC. Copyright ©2018, American Association for Cancer Research.

  13. Standard of Care and Promising New Agents for Triple Negative Metastatic Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Mancini, Patrizia, E-mail: patrizia.mancini@uniroma1.it [Department of Experimental Medicine, Sapienza University of Rome, Viale Regina Elena 324, Rome 00161 (Italy); Angeloni, Antonio [Department of Molecular Medicine, Sapienza University of Rome, Viale Regina Elena 324, Rome 00161 (Italy); Risi, Emanuela [Department of Radiology, Oncology and Human Pathology, Sapienza University of Rome, Viale Regina Elena 324, Rome 00161 (Italy); Orsi, Errico [Department of Surgical Science, Sapienza University of Rome, Viale Regina Elena 324, Rome 00161 (Italy); Mezi, Silvia [Department of Radiology, Oncology and Human Pathology, Sapienza University of Rome, Viale Regina Elena 324, Rome 00161 (Italy)

    2014-10-24

    Triple negative breast cancer (TNBC) is a cluster of heterogeneous diseases, all of them sharing the lack of expression of estrogen and progesterone receptors and HER2 protein. They are characterized by different biological, molecular and clinical features, including a poor prognosis despite the increased sensitivity to the current cytotoxic therapies. Several studies have identified important molecular features which enable further subdivision of this type of tumor. We are drawing from genomics, transcription and translation analysis at different levels, to improve our knowledge of the molecular alterations along the pathways which are activated during carcinogenesis and tumor progression. How this information should be used for the rational selection of therapy is an ongoing challenge and the subject of numerous research studies in progress. Currently, the vascular endothelial growth factor (VEGF), poly (ADP-ribose) polymerase (PARP), HSP90 and Aurora inhibitors are most used as targeting agents in metastatic setting clinical trials. In this paper we will review the current knowledge about the genetic subtypes of TNBC and their different responses to conventional therapeutic strategies, as well as to some new promising molecular target agents, aimed to achieve more tailored therapies.

  14. Standard of Care and Promising New Agents for Triple Negative Metastatic Breast Cancer

    Directory of Open Access Journals (Sweden)

    Patrizia Mancini

    2014-10-01

    Full Text Available Triple negative breast cancer (TNBC is a cluster of heterogeneous diseases, all of them sharing the lack of expression of estrogen and progesterone receptors and HER2 protein. They are characterized by different biological, molecular and clinical features, including a poor prognosis despite the increased sensitivity to the current cytotoxic therapies. Several studies have identified important molecular features which enable further subdivision of this type of tumor. We are drawing from genomics, transcription and translation analysis at different levels, to improve our knowledge of the molecular alterations along the pathways which are activated during carcinogenesis and tumor progression. How this information should be used for the rational selection of therapy is an ongoing challenge and the subject of numerous research studies in progress. Currently, the vascular endothelial growth factor (VEGF, poly (ADP-ribose polymerase (PARP, HSP90 and Aurora inhibitors are most used as targeting agents in metastatic setting clinical trials. In this paper we will review the current knowledge about the genetic subtypes of TNBC and their different responses to conventional therapeutic strategies, as well as to some new promising molecular target agents, aimed to achieve more tailored therapies.

  15. Carnosol: a promising anti-cancer and anti-inflammatory agent.

    Science.gov (United States)

    Johnson, Jeremy J

    2011-06-01

    The Mediterranean diet and more specifically certain meats, fruits, vegetables, and olive oil found in certain parts of the Mediterranean region have been associated with a decreased cardiovascular and diabetes risk. More recently, several population based studies have observed with these lifestyle choices have reported an overall reduced risk for several cancers. One study in particular observed an inverse relationship between consumption of Mediterranean herbs such as rosemary, sage, parsley, and oregano with lung cancer. In light of these findings there is a need to explore and identify the anti-cancer properties of these medicinal herbs and to identify the phytochemicals therein. One agent in particular, carnosol, has been evaluated for anti-cancer property in prostate, breast, skin, leukemia, and colon cancer with promising results. These studies have provided evidence that carnosol targets multiple deregulated pathways associated with inflammation and cancer that include nuclear factor kappa B (NFκB), apoptotic related proteins, phosphatidylinositol-3-kinase (PI3 K)/Akt, androgen and estrogen receptors, as well as molecular targets. In addition, carnosol appears to be well tolerated in that it has a selective toxicity towards cancer cells versus non-tumorigenic cells and is well tolerated when administered to animals. This mini-review reports on the pre-clinical studies that have been performed to date with carnosol describing mechanistic, efficacy, and safety/tolerability studies as a cancer chemoprevention and anti-cancer agent. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  16. Menahydroquinone-4 Prodrug: A Promising Candidate Anti-Hepatocellular Carcinoma Agent.

    Science.gov (United States)

    Enjoji, Munechika; Watase, Daisuke; Matsunaga, Kazuhisa; Kusuda, Mariko; Nagata-Akaho, Nami; Karube, Yoshiharu; Takata, Jiro

    2015-07-22

    Recently, new therapeutics have been developed for hepatocellular carcinoma (HCC). However, the overall survival rate of HCC patients is still unsatisfactory; one of the reasons for this is the high frequency of recurrence after radical treatment. Consequently, to improve prognosis, it will be important to develop a novel anti-tumor agent that is especially effective against HCC recurrence. For clinical application, long-term safety, together with high anti-tumor efficacy, is desirable. Recent studies have proposed menahydroquinone-4 1,4-bis- N,N -dimethylglycinate hydrochloride (MKH-DMG), a prodrug of menahydroquinone-4 (MKH), as a promising candidate for HCC treatment including the inhibition of recurrence; MKH-DMG has been shown to achieve good selective accumulation of MKH in tumor cells, resulting in satisfactory inhibition of cell proliferation in des-γ-carboxyl prothrombin (DCP)-positive and DCP-negative HCC cell lines. In a spleen-liver metastasis mouse model, MKH-DMG has been demonstrated to have anti-proliferation and anti-metastatic effects in vivo . The characteristics of MKH-DMG as a novel anti-HCC agent are presented in this review article.

  17. Gd (III) chelates adsorbed on TiO2 nanoparticles - promising MRI contrast agent

    International Nuclear Information System (INIS)

    Rehor, Ivan; Lukes, Ivan; Peters, Joop A.; Jirak, Daniel

    2009-01-01

    Full text: The project deals with a new contrast agent (CA) for magnetic resonance imaging (MRI). The CA consists of two main parts - diamagnetic core (TiO 2 nanoparticle) and Gd (III) chelates grafted on its surface. The presence of the nanoparticle core is responsible for significant increase of r1 millimolar relaxivity (which corresponds to the efficiency of the CA) due to the slowing down the rotation of the complex in solution. It also affects the biodistribution characteristics of the CA - the ability to penetrate through cell membranes is well known for nanoparticles, making them useful for cell labeling. The structure of the chelate is derived from DOTA ligand, whose Gd (III) complexes are commercially used as MRI CA in human medicine. The connection of the complex to the surface is realized via penylphosphonate, which is attached to the pendant arm of the ligand. Strong interaction of the phosphonate with the TiO 2 surface results in the full surface coverage. The complexation and MRI properties of Gd chelate were studied and exhibit analogy to the complexes of DOTA, The millimolar relaxivity (r1) of the Gd (III) complex significantly increases upon adsorption on the TiO 2 nanoparticles. PVA was added to the colloidal solutions of CA to stabilize them under biological conditions and such stabilized CA was utilized for MRI visualization of rat pancreatic islets (P1). The labeled islets were detected on MR images as hyperintense area and therefore our CA seems to be promising material for cellular MRI

  18. A critical ethnography of communication processes involving the management of oral chemotherapeutic agents by patients with a primary diagnosis of colorectal cancer: study protocol.

    Science.gov (United States)

    Mitchell, Gary; Porter, Sam; Manias, Elizabeth

    2015-04-01

    To describe the protocol used to examine the processes of communication between health professionals, patients and informal carers during the management of oral chemotherapeutic medicines to identify factors that promote or inhibit medicine concordance. Ideally communication practices about oral medicines should incorporate shared decision-making, two-way dialogue and an equality of role between practitioner and patient. While there is evidence that healthcare professionals are adopting these concordant elements in general practice there are still some patients who have a passive role during consultations. Considering oral chemotherapeutic medications, there is a paucity of research about communication practices which is surprising given the high risk of toxicity associated with chemotherapy. A critical ethnographic design will be used, incorporating non-participant observations, individual semi-structured and focus-group interviews as several collecting methods. Observations will be carried out on the interactions between healthcare professionals (physicians, nurses and pharmacists) and patients in the outpatient departments where prescriptions are explained and supplied and on follow-up consultations where treatment regimens are monitored. Interviews will be conducted with patients and their informal carers. Focus-groups will be carried out with healthcare professionals at the conclusion of the study. These several will be analysed using thematic analysis. This research is funded by the Department for Employment and Learning in Northern Ireland (Awarded February 2012). Dissemination of these findings will contribute to the understanding of issues involved when communicating with people about oral chemotherapy. It is anticipated that findings will inform education, practice and policy. © 2014 John Wiley & Sons Ltd.

  19. Pilot study on developing a decision support tool for guiding re-administration of chemotherapeutic agent after a serious adverse drug reaction

    Directory of Open Access Journals (Sweden)

    Chew Lita

    2011-07-01

    Full Text Available Abstract Background Currently, there are no standard guidelines for recommending re-administration of a chemotherapeutic drug to a patient after a serious adverse drug reaction (ADR incident. The decision on whether to rechallenge the patient is based on the experience of the clinician and is highly subjective. Thus the aim of this study is to develop a decision support tool to assist clinicians in this decision making process. Methods The inclusion criteria for patients in this study are: (1 had chemotherapy at National Cancer Centre Singapore between 2004 to 2009, (2 suffered from serious ADRs, and (3 were rechallenged. A total of 46 patients fulfilled the inclusion criteria. A genetic algorithm attribute selection method was used to identify clinical predictors for patients' rechallenge status. A Naïve Bayes model was then developed using 35 patients and externally validated using 11 patients. Results Eight patient attributes (age, chemotherapeutic drug, albumin level, red blood cell level, platelet level, abnormal white blood cell level, abnormal alkaline phosphatase level and abnormal alanine aminotransferase level were identified as clinical predictors for rechallenge status of patients. The Naïve Bayes model had an AUC of 0.767 and was found to be useful for assisting clinical decision making after clinicians had identified a group of patients for rechallenge. A platform independent version and an online version of the model is available to facilitate independent validation of the model. Conclusion Due to the limited size of the validation set, a more extensive validation of the model is necessary before it can be adopted for routine clinical use. Once validated, the model can be used to assist clinicians in deciding whether to rechallenge patients by determining if their initial assessment of rechallenge status of patients is accurate.

  20. N-acetylaspartate (NAA) induces neuronal differentiation of SH-SY5Y neuroblastoma cell line and sensitizes it to chemotherapeutic agents.

    Science.gov (United States)

    Mazzoccoli, Carmela; Ruggieri, Vitalba; Tataranni, Tiziana; Agriesti, Francesca; Laurenzana, Ilaria; Fratello, Angelo; Capitanio, Nazzareno; Piccoli, Claudia

    2016-05-03

    Neuroblastoma is the most commonly extra-cranial solid tumor of childhood frequently diagnosed. The nervous system-specific metabolite N-acetylaspartate (NAA) is synthesized from aspartate and acetyl-CoA in neurons, it is among the most abundant metabolites present in the central nervous system (CNS) and appears to be involved in many CNS disorders. The functional significance of the high NAA concentration in the brain remains uncertain, but it confers to NAA a unique clinical significance exploited in magnetic resonance spectroscopy. In the current study, we show that treatment of SH-SY5Y neuroblastoma-derived cell line with sub-cytotoxic physiological concentrations of NAA inhibits cell growth. This effect is partly due to enhanced apoptosis, shown by decrease of the anti-apoptotic factors survivin and Bcl-xL, and partly to arrest of the cell-cycle progression, linked to enhanced expression of the cyclin-inhibitors p53, p21Cip1/Waf1 and p27Kip1. Moreover, NAA-treated SH-SY5Y cells exhibited morphological changes accompanied with increase of the neurogenic markers TH and MAP2 and down-regulation of the pluripotency markers OCT4 and CXCR4/CD184. Finally, NAA-pre-treated SH-SY5Y cells resulted more sensitive to the cytotoxic effect of the chemotherapeutic drugs Cisplatin and 5-fluorouracil.To our knowledge, this is the first study demonstrating the neuronal differentiating effects of NAA in neuroblastoma cells. NAA may be a potential preconditioning or adjuvant compound in chemotherapeutic treatment.

  1. Graphene oxide-silver nanocomposite as a promising biocidal agent against methicillin-resistant Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    de Moraes ACM

    2015-11-01

    NPs within the tested concentration range. Transmission electronic microscopy images offered insights into how GO-Ag nanosheets interacted with bacterial cells. Conclusion: Our results indicate that the GO-Ag nanocomposite is a promising antibacterial agent against common nosocomial bacteria, particularly antibiotic-resistant MRSA. Morphological injuries on MRSA cells revealed a likely loss of viability as a result of the direct contact between bacteria and the GO-Ag sheets. Keywords: graphene oxide, silver nanoparticles, graphene oxide-silver nanocomposite, antibacterial agent, MRSA, Escherichia coli

  2. Graphene oxide-silver nanocomposite as a promising biocidal agent against methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    de Moraes, Ana Carolina Mazarin; Lima, Bruna Araujo; de Faria, Andreia Fonseca; Brocchi, Marcelo; Alves, Oswaldo Luiz

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) has been responsible for serious hospital infections worldwide. Nanomaterials are an alternative to conventional antibiotic compounds, because bacteria are unlikely to develop microbial resistance against nanomaterials. In the past decade, graphene oxide (GO) has emerged as a material that is often used to support and stabilize silver nanoparticles (AgNPs) for the preparation of novel antibacterial nanocomposites. In this work, we report the synthesis of the graphene-oxide silver nanocomposite (GO-Ag) and its antibacterial activity against relevant microorganisms in medicine. GO-Ag nanocomposite was synthesized through the reduction of silver ions (Ag(+)) by sodium citrate in an aqueous GO dispersion, and was extensively characterized using ultraviolet-visible absorption spectroscopy, X-ray diffraction, thermogravimetric analysis, X-ray photoelectron spectroscopy, and transmission electron microscopy. The antibacterial activity was evaluated by microdilution assays and time-kill experiments. The morphology of bacterial cells treated with GO-Ag was investigated via transmission electron microscopy. AgNPs were well distributed throughout GO sheets, with an average size of 9.4±2.8 nm. The GO-Ag nanocomposite exhibited an excellent antibacterial activity against methicillin-resistant S. aureus, Acinetobacter baumannii, Enterococcus faecalis, and Escherichia coli. All (100%) MRSA cells were inactivated after 4 hours of exposure to GO-Ag sheets. In addition, no toxicity was found for either pristine GO or bare AgNPs within the tested concentration range. Transmission electronic microscopy images offered insights into how GO-Ag nanosheets interacted with bacterial cells. Our results indicate that the GO-Ag nanocomposite is a promising antibacterial agent against common nosocomial bacteria, particularly antibiotic-resistant MRSA. Morphological injuries on MRSA cells revealed a likely loss of viability as a result of the

  3. The cell's nucleolus: an emerging target for chemotherapeutic intervention.

    Science.gov (United States)

    Pickard, Amanda J; Bierbach, Ulrich

    2013-09-01

    The transient nucleolus plays a central role in the up-regulated synthesis of ribosomal RNA (rRNA) to sustain ribosome biogenesis, a hallmark of aberrant cell growth. This function, in conjunction with its unique pathohistological features in malignant cells and its ability to mediate apoptosis, renders this sub-nuclear structure a potential target for chemotherapeutic agents. In this Minireview, structurally and functionally diverse small molecules are discussed that have been reported to either interact with the nucleolus directly or perturb its function indirectly by acting on its dynamic components. These molecules include all major classes of nucleic-acid-targeted agents, antimetabolites, kinase inhibitors, anti-inflammatory drugs, natural product antibiotics, oligopeptides, as well as nanoparticles. Together, these molecules are invaluable probes of structure and function of the nucleolus. They also provide a unique opportunity to develop novel strategies for more selective and therefore better-tolerated chemotherapeutic intervention. In this regard, inhibition of RNA polymerase-I-mediated rRNA synthesis appears to be a promising mechanism for killing cancer cells. The recent development of molecules targeted at G-quadruplex-forming rRNA gene sequences, which are currently undergoing clinical trials, seems to attest to the success of this approach. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Human toxoplasmosis-Searching for novel chemotherapeutics.

    Science.gov (United States)

    Antczak, Magdalena; Dzitko, Katarzyna; Długońska, Henryka

    2016-08-01

    The protozoan Toxoplasma gondii, an obligate intracellular parasite, is an etiological agent of human and animal toxoplasmosis. Treatment regimens for T. gondii-infected patients have not essentially changed for years. The most common chemotherapeutics used in the therapy of symptomatic toxoplasmosis are a combination of pyrimethamine and sulfadiazine plus folinic acid or a combination of pyrimethamine with lincosamide or macrolide antibiotics. To protect a fetus from parasite transplacental transmission, therapy of pregnant women is usually based on spiramycin, which is quite safe for the organism, but not efficient in the treatment of infected children. Application of recommended drugs limits replication of T. gondii, however, it may be associated with numerous an severe adverse effects. Moreover, medicines have no impact on the tissue cysts of the parasite located predominantly in a brain and muscles. Thus, there is urgent need to develop new drugs and establish "gold standard" treatment. In this review classical treatment of toxoplasmosis as well as potential compounds active against T. gondii have been discussed. For two last decades studies on the development of new anti-T. gondii medications have been focused on both natural and novel synthetic compounds based on existing chemical scaffolds. They have revealed several promising drug candidates characterized by a high selectivity, the low IC50 (the half maximal inhibitory concentration) and low cytotoxicity towards host cells. These drugs are expected to replace or supplement current anti-T. gondii drug arsenal soon. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  5. Benzofuran as a promising scaffold for the synthesis of antimicrobial and antibreast cancer agents: A review

    Directory of Open Access Journals (Sweden)

    Ghadamali Khodarahmi

    2015-01-01

    Full Text Available Benzofuran as an important heterocyclic compound is extensively found in natural products as well as synthetic materials. Since benzofuran drivatives display a diverse array of pharmacological activities, an interest in developing new biologically active agents from benzofuran is still under consideration. This review highlights recent findings on biological activities of benzofuran derivatives as antimicrobial and antibreast cancer agents and lays emphasis on the importance of benzofurans as a major source for drug design and development.

  6. Doxorubicin-loaded micelles of reverse poly(butylene oxide)-poly(ethylene oxide)-poly(butylene oxide) block copolymers as efficient "active" chemotherapeutic agents.

    Science.gov (United States)

    Cambón, A; Rey-Rico, A; Mistry, D; Brea, J; Loza, M I; Attwood, D; Barbosa, S; Alvarez-Lorenzo, C; Concheiro, A; Taboada, P; Mosquera, V

    2013-03-10

    Five reverse poly(butylene oxide)-poly(ethylene oxide)-poly(butylene oxide) block copolymers, BOnEOmBOn, with BO ranging from 8 to 21 units and EO from 90 to 411 were synthesized and evaluated as efficient chemotherapeutic drug delivery nanocarriers and inhibitors of the P-glycoprotein (P-gp) efflux pump in a multidrug resistant (MDR) cell line. The copolymers were obtained by reverse polymerization of poly(butylene oxide), which avoids transfer reaction and widening of the EO block distribution, commonly found in commercial poly(ethylene oxide)-poly(propylene oxide) block copolymers (poloxamers). BOnEOmBOn copolymers formed spherical micelles of 10-40 nm diameter at lower concentrations (one order of magnitude) than those of equivalent poloxamers. The influence of copolymer block lengths and BO/EO ratios on the solubilization capacity and protective environment for doxorubicin (DOXO) was investigated. Micelles showed drug loading capacity ranging from ca. 0.04% to 1.5%, more than 150 times the aqueous solubility of DOXO, and protected the cargo from hydrolysis for more than a month due to their greater colloidal stability in solution. Drug release profiles at various pHs, and the cytocompatibility and cytotoxicity of the DOXO-loaded micelles were assessed in vitro. DOXO loaded in the polymeric micelles accumulated more slowly inside the cells than free DOXO due to its sustained release. All copolymers were found to be cytocompatible, with viability extents larger than 95%. In addition, the cytotoxicity of DOXO-loaded micelles was higher than that observed for free drug solutions in a MDR ovarian NCI-ADR-RES cell line which overexpressed P-gp. The inhibition of the P-gp efflux pump by some BOnEOmBOn copolymers, similar to that measured for the common P-gp inhibitor verapamil, favored the retention of DOXO inside the cell increasing its cytotoxic activity. Therefore, poly(butylene oxide)-poly(ethylene oxide) block copolymers offer interesting features as cell

  7. Herbal radiation countermeasure agents: promising role in the management of radiological/nuclear exigencies

    International Nuclear Information System (INIS)

    Arora, Rajesh; Sharma, A.; Kumar, R.; Tripathi, R.P.

    2008-01-01

    In the future, there is a need to substantially boost biomass production and employ elicitors/precursors for improving the production of radioprotective compounds from such alternative sources for ensuring a sustainable supply of the high-value, low volume radioprotective molecules. Chemical fingerprinting, identification and characterization of bioactive constituents using modem analytical techniques and evaluation of their multifaceted mode of action at genomic/proteomic level is also the need of the hour. Such data will help in the development of novel, safe and effective radiation countermeasure agents for human use. Herbal radiation countermeasure agents, including several dietary agents, are likely to find large-scale acceptance in most countries in view of their widespread acceptance, holistic mode of action, less toxicity and economical nature. Endeavours made at INMAS in this direction are likely to fructify in coming years and radiation countermeasure agents from several of these herbal sources would become available, possibly several would be obtainable over-the-counter, for use by civilians, military personnel, first emergency responders and other rescue and recovery personnel. (author)

  8. 3-bromopyruvate: a new targeted antiglycolytic agent and a promise for cancer therapy.

    Science.gov (United States)

    Ganapathy-Kanniappan, S; Vali, M; Kunjithapatham, R; Buijs, M; Syed, L H; Rao, P P; Ota, S; Kwak, B K; Loffroy, R; Geschwind, J F

    2010-08-01

    The pyruvate analog, 3-bromopyruvate, is an alkylating agent and a potent inhibitor of glycolysis. This antiglycolytic property of 3-bromopyruvate has recently been exploited to target cancer cells, as most tumors depend on glycolysis for their energy requirements. The anticancer effect of 3-bromopyruvate is achieved by depleting intracellular energy (ATP) resulting in tumor cell death. In this review, we will discuss the principal mechanism of action and primary targets of 3-bromopyruvate, and report the impressive antitumor effects of 3-bromopyruvate in multiple animal tumor models. We describe that the primary mechanism of 3-bromopyruvate is via preferential alkylation of GAPDH and that 3-bromopyruvate mediated cell death is linked to generation of free radicals. Research in our laboratory also revealed that 3-bromopyruvate induces endoplasmic reticulum stress, inhibits global protein synthesis further contributing to cancer cell death. Therefore, these and other studies reveal the tremendous potential of 3-bromopyruvate as an anticancer agent.

  9. Bee Pollen as a Promising Agent in the Burn Wounds Treatment

    Directory of Open Access Journals (Sweden)

    Paweł Olczyk

    2016-01-01

    Full Text Available The aim of the present study was to visualize the benefits and advantages derived from preparations based on extracts of bee pollen as compared to pharmaceuticals commonly used in the treatment of burns. The bee pollen ointment was applied for the first time in topical burn treatment. Experimental burn wounds were inflicted on two white, domestic pigs. Clinical, histopathological, and microbiological assessment of specimens from burn wounds, inflicted on polish domestic pigs, treated with silver sulfadiazine or bee pollen ointment, was done. The comparative material was constituted by either tissues obtained from wounds treated with physiological saline or tissues obtained from wounds which were untreated. Clinical and histopathological evaluation showed that applied apitherapeutic agent reduces the healing time of burn wounds and positively affects the general condition of the animals. Moreover the used natural preparation proved to be highly effective antimicrobial agent, which was reflected in a reduction of the number of microorganisms in quantitative research and bactericidal activity of isolated strains. On the basis of the obtained bacteriological analysis, it may be concluded that the applied bee pollen ointment may affect the wound healing process of burn wounds, preventing infection of the newly formed tissue.

  10. Cytotoxic effects of the newly-developed chemotherapeutic agents 17-AAG in combination with oxaliplatin and capecitabine in colorectal cancer cell lines.

    Science.gov (United States)

    Mohammadian, Mahshid; Zeynali, Shima; Azarbaijani, Anahita Fathi; Khadem Ansari, Mohammad Hassan; Kheradmand, Fatemeh

    2017-12-01

    The use of heat shock protein 90 inhibitors like 17-allylamino-17-demethoxy-geldanamycin (17-AAG) has been recently introduced as an attractive anticancer therapy. It has been shown that 17-AAG may potentiate the inhibitory effects of some classical anticolorectal cancer (CRC) agents. In this study, two panels of colorectal carcinoma cell lines were used to evaluate the effects of 17-AAG in combination with capecitabine and oxaliplatin as double and triple combination therapies on the proliferation of CRC cell lines. HT-29 and all HCT-116 cell lines were seeded in culture media in the presence of different doses of the mentioned drugs in single, double, and triple combinations. Water-soluble tetrazolium-1 (WST-1) assay was used to investigate cell proliferation 24 h after treatments. Then, dose-response curves were plotted using WST-1outputs, and IC 50 values were determined. For double and triple combinations respectively 0.5 × IC 50 and 0.25 × IC 50 were used. Data was analyzed with the software CompuSyn. Drug interactions were analyzed using Chou-Talalay method to calculate the combination index (CI).The data revealed that 17-AAG shows a potent synergistic interaction (CI 1) in HT-29 and a synergistic effect (CI AAG with oxaliplatin or capecitabine might be effective against HCT-116 and HT-29 cell lines. However, in triple combinations, positive results were seen only against HCT-116. Further investigation is suggested to confirm the effectiveness of these combinations in clinical trials.

  11. Berberine as a promising safe anti-cancer agent - is there a role for mitochondria?

    Science.gov (United States)

    Diogo, Catia V; Machado, Nuno G; Barbosa, Inês A; Serafim, Teresa L; Burgeiro, Ana; Oliveira, Paulo J

    2011-06-01

    Metabolic regulation is largely dependent on mitochondria, which play an important role in energy homeostasis. Imbalance between energy intake and expenditure leads to mitochondrial dysfunction, characterized by a reduced ratio of energy production (ATP production) to respiration. Due to the role of mitochondrial factors/events in several apoptotic pathways, the possibility of targeting that organelle in the tumor cell, leading to its elimination is very attractive, although the safety issue is problematic. Berberine, a benzyl-tetra isoquinoline alkaloid extracted from plants of the Berberidaceae family, has been extensively used for many centuries, especially in the traditional Chinese and Native American medicine. Several evidences suggest that berberine possesses several therapeutic uses, including anti-tumoral activity. The present review supplies evidence that berberine is a safe anti-cancer agent, exerting several effects on mitochondria, including inhibition of mitochondrial Complex I and interaction with the adenine nucleotide translocator which can explain several of the described effects on tumor cells.

  12. Experimental FT-IR, Laser-Raman and DFT spectroscopic analysis of a potential chemotherapeutic agent 6-(2-methylpropyl)-4-oxo-2-sulfanylidene-1,2,3,4-tetrahydropyrimidine-5-carbonitrile.

    Science.gov (United States)

    Sert, Yusuf; Al-Turkistani, Abdulghafoor A; Al-Deeb, Omar A; El-Emam, Ali A; Ucun, Fatih; Çırak, Çağrı

    2014-01-01

    In this study, the experimental and theoretical vibrational frequencies of a newly synthesized potential chemotherapeutic agent namely, 6-(2-methylpropyl)-4-oxo-2-sulfanylidene-1,2,3,4-tetrahydropyrimidine-5-carbonitrile have been investigated. The experimental FT-IR (4000-400 cm(-1)) and Laser-Raman spectra (4000-100 cm(-1)) of the molecule in solid phase have been recorded. The theoretical vibrational frequencies and optimized geometric parameters (bond lengths and bond angles) have been calculated by using density functional theory (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr) and M06-2X (the highly parametrized, empirical exchange correlation function) quantum chemical methods with 6-311++G(d,p) basis set by Gaussian 09 W software, for the first time. The assignments of the vibrational frequencies have been done by potential energy distribution (PED) analysis by using VEDA 4 software. The theoretical optimized geometric parameters and vibrational frequencies have been found to be in good agreement with the corresponding experimental data, and with the results in the literature. In addition, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energies and the other related molecular energy values have been calculated and depicted. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Standoff Methods for the Detection of Threat Agents: A Review of Several Promising Laser-Based Techniques

    Directory of Open Access Journals (Sweden)

    J. Bruce Johnson

    2014-01-01

    Full Text Available Detection of explosives, explosive precursors, or other threat agents presents a number of technological challenges for optical sensing methods. Certainly detecting trace levels of threat agents against a complex background is chief among these challenges; however, the related issues of multiple target distances (from standoff to proximity and sampling time scales (from passive mines to rapid rate of march convoy protection for different applications make it unlikely that a single technique will be ideal for all sensing situations. A number of methods for spanning the range of optical sensor technologies exist which, when integrated, could produce a fused sensor system possessing a high level of sensitivity to threat agents and a moderate standoff real-time capability appropriate for portal screening of personnel or vehicles. In this work, we focus on several promising, and potentially synergistic, laser-based methods for sensing threat agents. For each method, we have briefly outlined the technique and report on the current level of capability.

  14. Pyramidatine (Z88) Sensitizes Vincristine-Resistant Human Oral Cancer (KB/VCR) Cells to Chemotherapeutic Agents by Inhibition of P-glycoprotein.

    Science.gov (United States)

    Liu, Zulong; Zhu, Hengrui; Qu, Shijin; Tang, Lisha; Cao, Lihuan; Yu, Wenbo; Yang, Xianmei; Jiang, Songmin; Zhu, Dayuan; Tan, Changheng; Yu, Long

    2018-01-01

    Multi-drug resistance (MDR) remains a major impediment in cancer therapy. A major goal for scientists is to discover more effective compounds that are able to circumvent MDR and simultaneously have minimal adverse side effects. In the present study, we aim to determine the anti-MDR effects of pyramidatine (Z88), a cinnamic acid-derived bisamide compound isolated from the leaves of Aglaia perviridis, on KB/VCR (vincristineresistant human oral cancer cells) and MCF-7/ADR (adriamycin-resistant human breast adenocarcinoma) cells. Cell viability and average resistant fold (RF) of Z88 were examined by Cell Counting Kit-8 (CCK-8) assay. Flow cytometry, western blot, RT-PCR, Rhodamine 123 accumulation assay and P-glycoprotein (P-gp) ATPase assay were used to demonstrate the anti-MDR activity and mechanism of Z88. The average RF of Z88 is 0.09 and 0.51 in KB/VCR and MCF-7/ADR cells. A CCK-8 assay showed that Z88 could enhance the cytotoxicity of VCR toward KB/VCR cells. A FACS analysis revealed that Z88 could enhance the VCR-induced apoptosis as well as G2/M arrest in a dose-dependent manner in KB/VCR cells. Western blot results showed that the expression levels of PARP, Bax, and cyclin B1 all increased after treatment with 0.2 µmol/L (µM) of VCR combined with 10 µM of Z88 for 24 h in KB/VCR cells. Z88 also could enhance the accumulation of rhodamine 123. Further studies showed that Z88 could inhibit the verapamil stimulated Pgp ATPase activity. Additionally, qPCR detection and western blot assays revealed that Z88 could decrease the expression of P-gp at both RNA and protein level. Z88 exerted potent anti-MDR activity in vitro and its mechanisms are associated with dualinhibition of the function and expression of P-gp. These findings encourage efforts to develop more effective reversal agents to circumvent MDR based on Z88. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  15. Current state of a dual behaviour of antimicrobial peptides-Therapeutic agents and promising delivery vectors.

    Science.gov (United States)

    Piotrowska, Urszula; Sobczak, Marcin; Oledzka, Ewa

    2017-12-01

    Micro-organism resistance is an important challenge in modern medicine due to the global uncontrolled use of antibiotics. Natural and synthetic antimicrobial peptides (AMPs) symbolize a new family of antibiotics, which have stimulated research and clinical interest as new therapeutic options for infections. They represent one of the most promising antimicrobial substances, due to their broad spectrum of biological activity, against bacteria, fungi, protozoa, viruses, yeast and even tumour cells. Besides, being antimicrobial, AMPs have been shown to bind and neutralize bacterial endotoxins, as well as possess immunomodulatory, anti-inflammatory, wound-healing, angiogenic and antitumour properties. In contrast to conventional antibiotics, which have very defined and specific molecular targets, host cationic peptides show varying, complex and very rapid mechanisms of actions that make it difficult to form an effective antimicrobial defence. Importantly, AMPs display their antimicrobial activity at micromolar concentrations or less. To do this, many peptide-based drugs are commercially available for the treatment of numerous diseases, such as hepatitis C, myeloma, skin infections and diabetes. Herein, we present an overview of the general mechanism of AMPs action, along with recent developments regarding carriers of AMPs and their potential applications in medical fields. © 2017 John Wiley & Sons A/S.

  16. Synthesis and Biological Evaluation of Liguzinediol Mono- and Dual Ester Prodrugs as Promising Inotropic Agents

    Directory of Open Access Journals (Sweden)

    Jing Zhang

    2014-11-01

    Full Text Available The potent positive inotropic effect, together with the relatively low safety risk of liguzinediol (LZDO, relative to currently available inotropic drugs, has prompted us to intensively research and develop LZDO as a potent positive inotropic agent. In this study, to obtain LZDO alternatives for oral chronic administration, a series of long-chain fatty carboxylic mono- and dual-esters of LZDO were synthesized, and preliminarily evaluated for physicochemical properties and bioconversion. Enhanced lipophilic properties and decreased solubility of the prodrugs were observed as the side chain length increased. All esters showed conspicuous chemical stability in phosphate buffer (pH 7.4. Moreover, the enzymatic hydrolysis of esters in human plasma and human liver microsomes confirmed that the majority of esters were converted to LZDO, with release profiles that varied due to the size and structure of the side chain. In vivo pharmacokinetic studies following oral administration of monopivaloyl (M5, monodecyl (M10 and monododecyl (M12 esters demonstrated the evidently extended half-lives relative to LZDO dosed alone. In particular the monopivaloyl ester M5 exhibited an optimal pharmacokinetic profile with appropriate physiochemical characteristics.

  17. Technetium-99m dextran: a promising new protein-losing enteropathy imaging agent

    International Nuclear Information System (INIS)

    Bhatnagar, A.; Singh, A.K.; Lahoti, D.; Singh, T.; Khanna, C.M.

    1996-01-01

    The purpose of this study was to evaluate technetium-99m dextran ( 99m Tc-Dx; molecular weight 81000) as a prospective protein-losing enteropathy (PLE) imaging agent. Twenty-two patients iwth diseases commonly associated with PLE and 12 healthy control subjects underwent intravenous 99m Tc-Dx scintigraphy. All of the 22 test patients showed significant radiotracer accumulation in the intestines within 3-4 h post injection. The focal, regional or generalised nature of the enteropathy and involvement of the large or small intestine could be identified in most cases. Four of the 12 apparently healthy subjects also showed minimal accumulation in the abdominal area occurring late in the study period. This could have been physiological, related to food habits or due to unsuspected intestinal worms. We attribute the high sensitivity of 99m Tc-Dx to its relatively fast blood (background) clearance. The radiotracer may have several other advantages over 99m Tc-labelled human serum albumin in imaging PLE. (orig.)

  18. Evaluation of the combined use of some radiolabeled chemotherapeutic agents and immunomodulator in imaging and treatment of experimentally induced tumor in mice

    International Nuclear Information System (INIS)

    Ali, E.T.E

    2008-01-01

    Ehrlich cells and this effect increased with the increase in radioactivity and of incubation time.Locoregional administration of 125 I-ANC or 125 I-Vid for consecutive 15 days, starting at the 3 rd day of inoculation showed significant decrease in the size of solid tumor.Daily and locoregional administration of 125 I-ANC or 125 I-Vid starting at the 3 rd day of inoculation were required to obtain maximum % survival in EAC bearing mice. Neither DEX nor LMS affect % survival, if they given alone or concurrently with 125 I-ANC or 125 I-Vid. Their effect occurs if mice pretreated with immunomodulators 10 days before inoculation. 125 I-Vid had no effect on hematological parameters indicating safety on normal mice. On the other hand, significant changes in the count of blood cells and hemoglobin were observed in normal mice subjected to DEX or LMS. 125 I-Vid produced significant changes in count of blood cells in ascites bearing mice. DEX or LMS alone or in combination with 125 I-Vid produced significant changes in blood cells count. 125 I-ANC or 125 I-Vid may be considered promising elements in radiotherapy to image and treat some types of tumor. Combination of 125 I-ANC or 125 I-Vid with immunostimulants may produce more reasonable results in treatment of cancer. Also, more investigations are needed to clarify the role of immunomodulators in cancer therapy.

  19. 99mTc-GHA: A promising agent for assessing tumour viability

    International Nuclear Information System (INIS)

    Choudhury, P.S.; Gupta, A.; Sharma, P.K.; Bhatia, S.; Nambiar, U.; Jena, A.

    2004-01-01

    chemotherapy had decreased intensity of GHA concentration in serial studies correlating with clinical improvement. 12 patients in the primary brain tumour group had further 15 studies during follow-up. The findings correlated modality, to raise the level of confidence in interpretation. Further studies should be directed towards its mechanism of action and its specificity as a simple and cheap tumour viability agent. (author)

  20. Antimicrobial Peptides Derived from Fusion Peptides of Influenza A Viruses, a Promising Approach to Designing Potent Antimicrobial Agents.

    Science.gov (United States)

    Wang, Jingyu; Zhong, Wenjing; Lin, Dongguo; Xia, Fan; Wu, Wenjiao; Zhang, Heyuan; Lv, Lin; Liu, Shuwen; He, Jian

    2015-10-01

    The emergence and dissemination of antibiotic-resistant bacterial pathogens have spurred the urgent need to develop novel antimicrobial agents with different mode of action. In this respect, we turned several fusogenic peptides (FPs) derived from the hemagglutinin glycoproteins (HAs) of IAV into potent antibacterials by replacing the negatively or neutrally charged residues of FPs with positively charged lysines. Their antibacterial activities were evaluated by testing the MICs against a panel of bacterial strains including S. aureus, S. mutans, P. aeruginosa, and E. coli. The results showed that peptides HA-FP-1, HA-FP-2-1, and HA-FP-3-1 were effective against both Gram-positive and Gram-negative bacteria with MICs ranging from 1.9 to 16.0 μm, while the toxicities toward mammalian cells were low. In addition, the mode of action and the secondary structure of these peptides were also discussed. These data not only provide several potent peptides displaying promising potential in development as broad antimicrobial agents, but also present a useful strategy in designing new antimicrobial agents. © 2015 John Wiley & Sons A/S.

  1. Removal of heavy metals from polluted soil using the citric acid fermentation broth: a promising washing agent.

    Science.gov (United States)

    Zhang, Hongjiao; Gao, Yuntao; Xiong, Huabin

    2017-04-01

    The citric acid fermentation broth was prepared and it was employed to washing remediation of heavy metal-polluted soil. A well-defined washing effect was obtained, the removal percentages using citric acid fermentation broth are that 48.2% for Pb, 30.6% for Cu, 43.7% for Cr, and 58.4% for Cd and higher than that using citric acid solution. The kinetics of heavy metals desorption can be described by the double constant equation and Elovich equation and is a heterogeneous diffusion process. The speciation analysis shows that the citric acid fermentation broth can effectively reduce bioavailability and environmental risk of heavy metals. Spectroscopy characteristics analysis suggests that the washing method has only a small effect on the mineral composition and does not destroy the framework of soil system. Therefore, the citric acid fermentation broth is a promising washing agent and possesses a potential practical application value in the field of remediation of soils with a good washing performance.

  2. Coral-Associated Bacteria as a Promising Antibiofilm Agent against Methicillin-Resistant and -Susceptible Staphylococcus aureus Biofilms

    Directory of Open Access Journals (Sweden)

    Shanmugaraj Gowrishankar

    2012-01-01

    Full Text Available The current study deals with the evaluation of two coral-associated bacterial (CAB extracts to inhibit the biofilm synthesis in vitro as well as the virulence production like hemolysin and exopolysaccharide (EPS, and also to assess their ability to modify the adhesion properties, that is cell surface hydrophobicity (CSH of methicillin-resistant (MRSA and -susceptible Staphylococcus aureus (MSSA. Out of nine CAB screened, the ethyl acetate extract of CAB-E2 (Bacillus firmus and CAB-E4 (Vibrio parahemolyticus have shown excellent antibiofilm activity against S. aureus. CAB-E2 reduced the production of EPS (57–79% and hemolysin (43–70%, which ultimately resulted in the significant inhibition of biofilms (80–87% formed by both MRSA and MSSA. Similarly, CAB-E4 was also found to decrease the production of EPS (43–57%, hemolysin (43–57% and biofilms (80–85% of test pathogens. CLSM analysis also proved the antibiofilm efficacy of CAB extracts. Furthermore, the CAB extracts strongly decreased the CSH of S. aureus. Additionally, FT-IR analysis of S. aureus treated with CAB extracts evidenced the reduction in cellular components compared to their respective controls. Thus, the present study reports for the first time, B. firmus—a coral-associated bacterium, as a promising source of antibiofilm agent against the recalcitrant biofilms formed by multidrug resistant S. aureus.

  3. Co-delivery of chemotherapeutics and proteins for synergistic therapy.

    Science.gov (United States)

    He, Chaoliang; Tang, Zhaohui; Tian, Huayu; Chen, Xuesi

    2016-03-01

    Combination therapy with chemotherapeutics and protein therapeutics, typically cytokines and antibodies, has been a type of crucial approaches for synergistic cancer treatment. However, conventional approaches by simultaneous administration of free chemotherapeutic drugs and proteins lead to limitations for further optimizing the synergistic effects, due to the distinct in vivo pharmacokinetics and distribution of small drugs and proteins, insufficient tumor selectivity and tumor accumulation, unpredictable drug/protein ratios at tumor sites, short half-lives, and serious systemic adverse effects. Consequently, to obtain optimal synergistic anti-tumor efficacy, considerable efforts have been devoted to develop the co-delivery systems for co-incorporating chemotherapeutics and proteins into a single carrier system and subsequently releasing the dual or multiple payloads at desired target sites in a more controllable manner. The co-delivery systems result in markedly enhanced blood stability and in vivo half-lives of the small drugs and proteins, elevated tumor accumulation, as well as the capability of delivering the multiple agents to the same target sites with rational drug/protein ratios, which may facilitate maximizing the synergistic effects and therefore lead to optimal antitumor efficacy. This review emphasizes the recent advances in the co-delivery systems for chemotherapeutics and proteins, typically cytokines and antibodies, for systemic or localized synergistic cancer treatment. Moreover, the proposed mechanisms responsible for the synergy of chemotherapeutic drugs and proteins are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Self-assembled Nanomaterials for Chemotherapeutic Applications

    Science.gov (United States)

    Shieh, Aileen

    The self-assembly of short designed peptides into functional nanostructures is becoming a growing interest in a wide range of fields from optoelectronic devices to nanobiotechnology. In the medical field, self-assembled peptides have especially attracted attention with several of its attractive features for applications in drug delivery, tissue regeneration, biological engineering as well as cosmetic industry and also the antibiotics field. We here describe the self-assembly of peptide conjugated with organic chromophore to successfully deliver sequence independent micro RNAs into human non-small cell lung cancer cell lines. The nanofiber used as the delivery vehicle is completely non-toxic and biodegradable, and exhibit enhanced permeability effect for targeting malignant tumors. The transfection efficiency with nanofiber as the delivery vehicle is comparable to that of the commercially available RNAiMAX lipofectamine while the toxicity is significantly lower. We also conjugated the peptide sequence with camptothecin (CPT) and observed the self-assembly of nanotubes for chemotherapeutic applications. The peptide scaffold is non-toxic and biodegradable, and drug loading of CPT is high, which minimizes the issue of systemic toxicity caused by extensive burden from the elimination of drug carriers. In addition, the peptide assembly drastically increases the solubility and stability of CPT under physiological conditions in vitro, while active CPT is gradually released from the peptide chain under the slight acidic tumor cell environment. Cytotoxicity results on human colorectal cancer cells and non-small cell lung cancer cell lines display promising anti-cancer properties compared to the parental CPT drug, which cannot be used clinically due to its poor solubility and lack of stability in physiological conditions. Moreover, the peptide sequence conjugated with 5-fluorouracil formed a hydrogel with promising topical chemotherapeutic applications that also display

  5. Synthesis and characterization of Cu(II)-based anticancer chemotherapeutic agent targeting topoisomerase Iα: in vitro DNA binding, pBR322 cleavage, molecular docking studies and cytotoxicity against human cancer cell lines.

    Science.gov (United States)

    Tabassum, Sartaj; Zaki, Mehvash; Afzal, Mohd; Arjmand, Farukh

    2014-03-03

    New metal-based anticancer chemotherapeutic drug candidates [Cu(phen)L](NO₃)₂ (1) and [Zn(phen)L](NO₃)₂ (2) were synthesized from ligand L (derived from pharmacophore scaffold barbituric acid and pyrazole). In vitro DNA binding studies of the L, 1 and 2 were carried out by various biophysical techniques revealing electrostatic mode. Complex 1 cleaves pBR322 DNA via oxidative pathway and recognizes major groove of DNA double helix. The molecular docking study was carried out to ascertain the mode of action towards the molecular target DNA and enzymes. The complex 1 exhibited remarkably good anticancer activity on a panel of human cancer cell lines (GI₅₀ values < 10 μg/ml), and to elucidate the mechanism of cancer inhibition, Topo-I enzymatic activity was carried out. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  6. Biology and life history of Argopistes tsekooni (Coleoptera: Chrysomelidae) in China, a promising biological control agent of Chinese privet.

    Science.gov (United States)

    Y-Z Zhang; J. Sun; J.L. Hanula

    2009-01-01

    The biology and life history of Argopistes tsekooni Chen (Coleoptera: Chrysomelidae), a potential biological control agent of Chinese privet, Ligustrum sinense Lour., was studied under laboratory and outdoor conditions in Huangshan City of Anhui Province, China, in 2006. A. tsekooni larvae are leafminers that...

  7. The use of chemotherapeutics for the treatment of keloid scars

    Directory of Open Access Journals (Sweden)

    Christopher David Jones

    2015-05-01

    Full Text Available Keloid scars are pathological scars, which develop as a result of exaggerated dermal tissue proliferation following cutaneous injury and often cause physical, psychological and cosmetic problems. Various theories regarding keloidogenesis exist, however the precise pathophysiological events remain unclear. Many different treatment modalities have been implicated in their management, but currently there is no entirely satisfactory method for treating all keloid lesions. We review a number of different chemotherapeutic agents which have been proposed for the treatment of keloid and hypertrophic scars while giving insight into some of the novel chemotherapeutic drugs which are currently being investigated. Non-randomized trials evaluating the influence of different chemotherapeutic agents, such as 5-fluorouracil (5-FU; mitomycin C; bleomycin and steroid injection, either alone or in combination with other chemotherapeutic agents or alternative treatment modalities, for the treatment of keloids were identified using a predefined PubMed search strategy. Twenty seven papers were identified. Scar improvement ≥50% was found in the majority of cases treated with 5-FU, with similar results found for mitomycin C, bleomycin and steroid injection. Combined intralesional 5-FU and steroid injection produced statistically significant improvements when compared to monotherapy. Monotherapy recurrence rates ranged from 0-47% for 5-FU, 0-15% for bleomycin and 0-50% for steroid injection. However, combined therapy in the form of surgical excision and adjuvant 5-FU or steroid injections demonstrated lower recurrence rates; 19% and 6% respectively. Currently, most of the literature supports the use of combination therapy (usually surgery and adjuvant chemotherapy as the mainstay treatment of keloids, however further investigation is necessary to determine success rates over longer time frames. Furthermore, there is the potential for novel therapies, but further

  8. Newly Synthesized Water Soluble Cholinium-Purpurin Photosensitizers and Their Stabilized Gold Nanoparticles as Promising Anticancer Agents

    Directory of Open Access Journals (Sweden)

    Young Key Shim

    2008-05-01

    Full Text Available For possible future use in Photodynamic Therapy (PDT and/or Photothermal Therapy (PTT of cancer and screening of cancer cells a new type of ionic liquid photosensitizer –Cholinium-Purpurin-18 (Chol-Pu-18 – was synthesized and small gold (Au nanoparticles, stabilized by this photosensitizer were prepared without adding any particular reducing agents and CTAB. UV-Vis spectroscopy and Transmission Electron Microscopy (TEM were used for characterization of the nanoparticles and FAB-MS and NMR of the ionic liquid choline hydroxide, purpurin carboxylate and their ionic liquid type of photosensitizer were obtained.

  9. Trial watch: Immunogenic cell death induction by anticancer chemotherapeutics.

    Science.gov (United States)

    Garg, Abhishek D; More, Sanket; Rufo, Nicole; Mece, Odeta; Sassano, Maria Livia; Agostinis, Patrizia; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, Lorenzo

    2017-01-01

    The expression "immunogenic cell death" (ICD) refers to a functionally unique form of cell death that facilitates (instead of suppressing) a T cell-dependent immune response specific for dead cell-derived antigens. ICD critically relies on the activation of adaptive responses in dying cells, culminating with the exposure or secretion of immunostimulatory molecules commonly referred to as "damage-associated molecular patterns". Only a few agents can elicit bona fide ICD, including some clinically established chemotherapeutics such as doxorubicin, epirubicin, idarubicin, mitoxantrone, bleomycin, bortezomib, cyclophosphamide and oxaliplatin. In this Trial Watch, we discuss recent progress on the development of ICD-inducing chemotherapeutic regimens, focusing on studies that evaluate clinical efficacy in conjunction with immunological biomarkers.

  10. Participation of MT3 melatonin receptors in the synergistic effect of melatonin on cytotoxic and apoptotic actions evoked by chemotherapeutics.

    Science.gov (United States)

    Pariente, Roberto; Bejarano, Ignacio; Espino, Javier; Rodríguez, Ana B; Pariente, José A

    2017-11-01

    Melatonin has antitumor activity via several mechanisms including its antiproliferative and proapoptotic effects in addition to its potent antioxidant actions. Therefore, melatonin may be useful in the treatment of tumors in association with chemotherapy drugs. This study was performed to study the role of melatonin receptors on the cytotoxicity and apoptosis induced by the chemotherapeutic agents cisplatin and 5-fluorouracil in two tumor cell lines, such as human colorectal cancer HT-29 cells and cervical cancer HeLa cells. We found that both melatonin and the two chemotherapeutic agents tested induced a decrease in HT-29 and HeLa cell viability. Furthermore, melatonin significantly increased the cytotoxic effect of chemotherapeutic agents, particularly, in 5-fluorouracil-challenged cells. Stimulation of cells with either of the two chemotherapeutic agents in the presence of melatonin further increased caspase-3 activation. Concomitant treatments with melatonin and chemotherapeutic agents augmented the population of apoptotic cells compared to the treatments with chemotherapeutics alone. Blockade of MT1 and/or MT2 receptors with luzindole or 4-P-PDOT was unable to reverse the enhancing effects of melatonin on both cytotoxicity, caspase-3 activation and the amount of apoptotic cells evoked by the chemotherapeutic agents, whereas when MT3 receptors were blocked with prazosin, the synergistic effect of melatonin with chemotherapy on cytotoxicity and apoptosis was reversed. Our findings provided evidence that in vitro melatonin strongly enhances chemotherapeutic-induced cytotoxicity and apoptosis in two tumor cell lines, namely HT-29 and HeLa cells and, this potentiating effect of melatonin is mediated by MT3 receptor stimulation.

  11. A review on the chemotherapeutic potential of fisetin: In vitro evidences.

    Science.gov (United States)

    Sundarraj, Kiruthika; Raghunath, Azhwar; Perumal, Ekambaram

    2018-01-01

    During the past five decades, cancer cell lines are being successfully used as an in vitro model to discover the anti-cancer potential of plant secondary metabolites. Fisetin - the most popular polyphenol from fruits and vegetables, exhibits a repertoire of promising pharmacological features. Such versatile properties make fisetin an excellent anticancer agent and its efficacy as a chemotherapeutic agent against tumor heterogeneity from in vitro studies are encouraging. Fisetin is like a Pandora's box, as more research studies are being carried out, it reveals its new molecules within the cancer cells as therapeutic targets. These molecular targets orchestrate processes such as apoptosis, autophagic cell death, cell cycle, invasion, metastasis and angiogenesis in cancer cells. Besides apoptotic elicitation, fisetin's ability to induce autophagic cell death in cancer cells has been reported. This review examines the various molecular mechanisms of action elicited by fisetin leading to apoptosis and autophagic cell death as evidenced from cancer cell lines. In addition, the increased bioavailability and sustained release of fisetin improved through conjugation and enhanced effect of fisetin through synergism on various cancers are also highlighted. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  12. Phase-contrast cerebrospinal fluid flow magnetic resonance imaging in qualitative evaluation of patency of CSF flow pathways prior to infusion of chemotherapeutic and other agents into the fourth ventricle.

    Science.gov (United States)

    Patel, Rajan P; Sitton, Clark W; Ketonen, Leena M; Hou, Ping; Johnson, Jason M; Romo, Seferino; Fletcher, Stephen; Shah, Manish N; Kerr, Marcia; Zaky, Wafik; Rytting, Michael E; Khatua, Soumen; Sandberg, David I

    2018-03-01

    Nuclear medicine studies have previously been utilized to assess for blockage of cerebrospinal fluid (CSF) flow prior to intraventricular chemotherapy infusions. To assess CSF flow without nuclear medicine studies, we obtained cine phase-contrast MRI sequences that assess CSF flow from the fourth ventricle down to the sacrum. In three clinical trials, 18 patients with recurrent malignant posterior fossa tumors underwent implantation of a ventricular access device (VAD) into the fourth ventricle, either with or without simultaneous tumor resection. Prior to infusing therapeutic agents into the VAD, cine MRI phase-contrast CSF flow sequences of the brain and total spine were performed. Velocity encoding (VENC) of 5 and 10 cm/s was used to confirm CSF flow from the fourth ventricular outlets to the cervical, thoracic, and lumbar spine. Qualitative CSF flow was characterized by neuroradiologists as present or absent. All 18 patients demonstrated CSF flow from the outlets of the fourth ventricle down to the sacrum with no evidence of obstruction. One of these patients, after disease progression, subsequently showed obstruction of CSF flow. No patient required a nuclear medicine study to assess CSF flow prior to initiation of infusions. Fourteen patients have received infusions to date, and none has had neurological toxicity. CSF flow including the fourth ventricle and the total spine can be assessed noninvasively with phase-contrast MRI sequences. Advantages over nuclear medicine studies include avoiding both an invasive procedure and radiation exposure.

  13. Cellular internalization and morphological analysis after intravenous injection of a highly hydrophilic octahedral rhenium cluster complex - a new promising X-ray contrast agent.

    Science.gov (United States)

    Krasilnikova, Anna A; Solovieva, Anastasiya O; Trifonova, Kristina E; Brylev, Konstantin A; Ivanov, Anton A; Kim, Sung-Jin; Shestopalov, Michael A; Fufaeva, Maria S; Shestopalov, Alexander M; Mironov, Yuri V; Poveshchenko, Alexander F; Shestopalova, Lidia V

    2016-11-01

    The octahedral cluster compound Na 2 H 8 [{Re 6 Se 8 }(P(C 2 H 4 CONH 2 )(C 2 H 4 COO) 2 ) 6 ] has been shown to be highly radio dense, thus becoming a promising X-ray contrast agent. It was also shown that this compound had low cytotoxic effect in vitro, low acute toxicity in vivo and was eliminated rapidly from the body through the urinary tract. The present contribution describes a more detailed cellular internalization assay and morphological analysis after intravenous injection of this hexarhenium cluster compound at different doses. The median lethal dose (LD 50 ) of intravenously administrated compound was calculated (4.67 ± 0.69 g/kg). Results of the study clearly indicated that the cluster complex H n [{Re 6 Se 8 }(P(C 2 H 4 CONH 2 )(C 2 H 4 COO) 2 ) 6 ] n-10 was not internalized into cells in vitro and induced only moderate morphological alterations of kidneys at high doses without any changes in morphology of liver, spleen, duodenum, or heart of mice. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  14. Ixabepilone: a new chemotherapeutic option for refractory metastatic breast cancer

    Directory of Open Access Journals (Sweden)

    Shannon Puhalla

    2008-09-01

    Full Text Available Shannon Puhalla, Adam BrufskyUPMC Magee-Womens Cancer Program, University of Pittsburgh, Pittsburgh, Pennsylvania, USAAbstract: Taxane therapy is commonly used in the treatment of metastatic breast cancer. However, most patients will eventually become refractory to these agents. Ixabepilone is a newly approved chemotherapeutic agent for the treatment of metastatic breast cancer. Although it targets microtubules similarly to docetaxel and paclitaxel, ixabepilone has activity in patients that are refractory to taxanes. This review summarizes the pharmacology of ixapebilone and clinical trials with the drug both as a single agent and in combination. Data were obtained using searches of PubMed and abstracts of the annual meetings of the American Society of Clinical Oncology and the San Antonio Breast Cancer Symposium from 1995 to 2008. Ixapebilone is a semi-synthetic analog of epothilone B that acts to induce apoptosis of cancer cells via the stabilization of microtubules. Phase I clinical trials have employed various dosing schedules ranging from daily to weekly to 3-weekly. Dose-limiting toxicites included neuropathy and neutropenia. Responses were seen in a variety of tumor types. Phase II studies verified activity in taxane-refractory metastatic breast cancer. The FDA has approved ixabepilone for use as monotherapy and in combination with capecitabine for the treatment of metastatic breast cancer. Ixabepilone is an efficacious option for patients with refractory metastatic breast cancer. The safety profile is similar to that of taxanes, with neuropathy and neutropenia being dose-limiting. Studies are ongoing with the use of both iv and oral formulations and in combination with other chemotherapeutic and biologic agents.Keywords: ixabepilone, epothilone, metastatic breast cancer, taxane-refractory

  15. In vitro evaluation of the cyto-genotoxic potential of Ruthenium(II) SCAR complexes: a promising class of antituberculosis agents.

    Science.gov (United States)

    De Grandis, Rone Aparecido; Resende, Flávia Aparecida; da Silva, Monize Martins; Pavan, Fernando Rogério; Batista, Alzir Azevedo; Varanda, Eliana Aparecida

    2016-03-01

    Tuberculosis is a top infectious disease killer worldwide, caused by the bacteria Mycobacterium tuberculosis. Increasing incidences of multiple drug-resistance (MDR) strains are emerging as one of the major public health threats. However, the drugs in use are still incapable of controlling the appalling upsurge of MDR. In recent years a marked number of research groups have devoted their attention toward the development of specific and cost-effective antimicrobial agents against targeted MDR-Tuberculosis. In previous studies, ruthenium(II) complexes (SCAR) have shown a promising activity against MDR-Tuberculosis although few studies have indeed considered ruthenium toxicity. Therefore, within the preclinical requirements, we have sought to determine the cyto-genotoxicity of three SCAR complexes in this present study. The treatment with the SCARs induced a concentration-dependent decrease in cell viability in CHO-K1 and HepG2 cells. Based on the clonogenic survival, SCAR 5 was found to be more cytotoxic while SCAR 6 exhibited selectivity action on tumor cells. Although SCAR 4 and 5 did not indicate any mutagenic activity as evidenced by the Ames and Cytokinesis block micronucleus cytome assays, the complex SCAR 6 was found to engender a frameshift mutation detected by Salmonella typhimurium in the presence of S9. Similarly, we observed a chromosomal damage in HepG2 cells with significant increases of micronuclei and nucleoplasmic bridges. These data indicate that SCAR 4 and 5 complexes did not show genotoxicity in our models while SCAR 6 was considered mutagenic. This study presented a comprehensive genotoxic evaluation of SCAR complexes were shown to be genotoxic in vitro. All in all, further studies are required to fully elucidate how the properties can affect human health. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Dissociative electron attachment to the radiosensitizing chemotherapeutic agent hydroxyurea

    Science.gov (United States)

    Huber, S. E.; Śmiałek, M. A.; Tanzer, K.; Denifl, S.

    2016-06-01

    Dissociative electron attachment to hydroxyurea was studied in the gas phase for electron energies ranging from zero to 9 eV in order to probe its radiosensitizing capabilities. The experiments were carried out using a hemispherical electron monochromator coupled with a quadrupole mass spectrometer. Diversified fragmentation of hydroxyurea was observed upon low energy electron attachment and here we highlight the major dissociation channels. Moreover, thermodynamic thresholds for various fragmentation reactions are reported to support the discussion of the experimental findings. The dominant dissociation channel, which was observed over a broad range of energies, is associated with formation of NCO-, water, and the amidogen (NH2) radical. The second and third most dominant dissociation channels are associated with formation of NCNH- and NHCONH2-, respectively, which are both directly related to formation of the highly reactive hydroxyl radical. Other ions observed with significant abundance in the mass spectra were NH2-/O-, OH-, CN-, HNOH-, NCONH2-, and ONHCONH2-.

  17. Dissociative electron attachment to the radiosensitizing chemotherapeutic agent hydroxyurea

    Energy Technology Data Exchange (ETDEWEB)

    Huber, S. E.; Tanzer, K.; Denifl, S. [Institute for Ion Physics and Applied Physics and Center of Molecular Biosciences Innsbruck, Leopold Franzens University of Innsbruck, Technikerstr. 25, 6020 Innsbruck (Austria); Śmiałek, M. A., E-mail: smialek@pg.gda.pl [Department of Control and Power Engineering, Faculty of Ocean Engineering and Ship Technology, Gdańsk University of Technology, Gabriela Narutowicza 11/12, 80-233 Gdańsk (Poland)

    2016-06-14

    Dissociative electron attachment to hydroxyurea was studied in the gas phase for electron energies ranging from zero to 9 eV in order to probe its radiosensitizing capabilities. The experiments were carried out using a hemispherical electron monochromator coupled with a quadrupole mass spectrometer. Diversified fragmentation of hydroxyurea was observed upon low energy electron attachment and here we highlight the major dissociation channels. Moreover, thermodynamic thresholds for various fragmentation reactions are reported to support the discussion of the experimental findings. The dominant dissociation channel, which was observed over a broad range of energies, is associated with formation of NCO{sup −}, water, and the amidogen (NH{sub 2}) radical. The second and third most dominant dissociation channels are associated with formation of NCNH{sup −} and NHCONH{sub 2}{sup −}, respectively, which are both directly related to formation of the highly reactive hydroxyl radical. Other ions observed with significant abundance in the mass spectra were NH{sub 2}{sup −}/O{sup −}, OH{sup −}, CN{sup −}, HNOH{sup −}, NCONH{sub 2}{sup −}, and ONHCONH{sub 2}{sup −}.

  18. Synthesis of Taxol-Like Prostate Cancer Chemotherapeutic Agents

    National Research Council Canada - National Science Library

    Jo, Hyunil

    2008-01-01

    This report describes the synthetic approaches toward a potent microtubule stabilizing natural product, eleutherobin, utilizing tandem Diels-Alder reaction/Grob-type fragmentation reaction as key steps...

  19. Characteristics and overcome of the resistance to chemotherapeutic agents

    International Nuclear Information System (INIS)

    Hong, Weon Seon; Im, Young Hyuck; Kim, Young Sun

    1993-01-01

    Although the clinical use of colony-stimulating factor (CSF) improves the therapeutic results, there have been a lot of evidences that CSF may stimulate the growth of cancer cells. This study was conducted to investigate the effects of granulocytemacrophage(GM)-CSF and granulocyte(G)-CSF on the colony formations in eight human cancer cell lines. The stimulatory effects of GM-CSF and G-CSF on the colony formation were evaluated in human tumor colony assay against four human cancer cell lines, four sublines resistant to adriamycin or cisplatin : PC-9 and PC-14 (pulmonary adenoca), MKN-45 and KATO III (gastric adenoca), PC/ADM and PC/CDDP (sublines of PC-14 resistant to adriamycin and cisplatin, respectively), MKN/ADM and MKN/CDDP (sublines of MKN-45 resistant to adriamycin and cisplatin, respectively). Cancer cells were plated at concentrations of 1x10 3 and 1x10 5 cells/well in the upper layer. Two kinds of GM-CSF (LBD-005 and CSF 39-300) and two kinds of G-CSF (Grasin and Neutrogin) were tested by the addition of final concentrations of GM-CSF and G-CSF (0.01, 0.1 and 1.0 μg/ml) to the lower layer to allow continuous exposure for 14 days. The colony formations (%) of eight cell lines tested were 85-113% and 92-106% in wells plated at the concentrations (/well) of 1x10 3 and 1x10 5 plated, respectively, in all cell lines compared to those of control wells. These results suggest that GM-CSF and G-CSF dose not directly stimulate the growth of cancer cells in all cell lines tested. (Author)

  20. Safe practices and financial considerations in using oral chemotherapeutic agents.

    Science.gov (United States)

    Bartel, Sylvia B

    2007-05-01

    Safe handling practices and financial concerns associated with oral chemotherapy in non-traditional settings are discussed. Oral chemotherapy may pose a risk to patients because of a narrow therapeutic index, complex dosing regimen, dispensing by community pharmacists without prescription order review by an oncology pharmacist or nurse, or self-administration in the home or another nontraditional setting, where patient monitoring is infrequent. Errors in prescribing, dispensing, and administration and patient or caregiver misunderstandings are potential problems with the use of oral chemotherapy that need to be addressed when developing safe practices. Changes in Medicare pharmaceutical reimbursement rates and rules need to be monitored because they have the potential to affect patient care and outcomes. Patient assistance programs and advocacy groups can help alleviate financial concerns associated with oral chemotherapy. Consensus guidelines specific to safe handling of oral chemotherapy in the home or other nontraditional setting need to be developed. Also, healthcare providers must understand reimbursement and provide direction to patients when patient assistance programs or advocacy groups can assist with the financial challenges of oral chemotherapy.

  1. Chemotherapy Agents: A Primer for the Interventional Radiologist

    OpenAIRE

    Mihlon, Frank; Ray, Charles E.; Messersmith, Wells

    2010-01-01

    In this article, the authors review the basic principles of cancer chemotherapy and provide an overview of each of the general classes of chemotherapeutic agents with a target audience of interventional radiologists in mind. Special attention is paid to agents used in regional chemotherapy as well as agents commonly included in systemic chemotherapeutic regimens for patients who also require regional chemotherapy.

  2. Fuzzy promises

    DEFF Research Database (Denmark)

    Anker, Thomas Boysen; Kappel, Klemens; Eadie, Douglas

    2012-01-01

    as narrative material to communicate self-identity. Finally, (c) we propose that brands deliver fuzzy experiential promises through effectively motivating consumers to adopt and play a social role implicitly suggested and facilitated by the brand. A promise is an inherently ethical concept and the article...... concludes with an in-depth discussion of fuzzy brand promises as two-way ethical commitments that put requirements on both brands and consumers....

  3. 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.

  4. Animal venoms as antimicrobial agents.

    Science.gov (United States)

    Perumal Samy, Ramar; Stiles, Bradley G; Franco, Octavio L; Sethi, Gautam; Lim, Lina H K

    2017-06-15

    Hospitals are breeding grounds for many life-threatening bacteria worldwide. Clinically associated gram-positive bacteria such as Staphylococcus aureus/methicillin-resistant S. aureus and many others increase the risk of severe mortality and morbidity. The failure of antibiotics to kill various pathogens due to bacterial resistance highlights the urgent need to develop novel, potent, and less toxic agents from natural sources against various infectious agents. Currently, several promising classes of natural molecules from snake (terrestrial and sea), scorpion, spider, honey bee and wasp venoms hold promise as rich sources of chemotherapeutics against infectious pathogens. Interestingly, snake venom-derived synthetic peptide/snake cathelicidin not only has potent antimicrobial and wound-repair activity but is highly stable and safe. Such molecules are promising candidates for novel venom-based drugs against S. aureus infections. The structure of animal venom proteins/peptides (cysteine rich) consists of hydrophobic α-helices or β-sheets that produce lethal pores and membrane-damaging effects on bacteria. All these antimicrobial peptides are under early experimental or pre-clinical stages of development. It is therefore important to employ novel tools for the design and the development of new antibiotics from the untapped animal venoms of snake, scorpion, and spider for treating resistant pathogens. To date, snail venom toxins have shown little antibiotic potency against human pathogens. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Whole-genome sequence of Pseudomonas fluorescens EK007-RG4, a promising biocontrol agent against a broad range of bacteria, including the fire blight bacterium Erwinia amylovora

    DEFF Research Database (Denmark)

    Habibi, Roghayeh; Tarighi, Saeed; Behravan, Javad

    2017-01-01

    Here, we report the first draft whole-genome sequence of Pseudomonas fluorescens strain EK007-RG4, which was isolated from the phylloplane of a pear tree. P. fluorescens EK007-RG4 displays strong antagonism against Erwinia amylovora, the causal agent for fire blight disease, in addition to several...

  6. [Alkylating agents].

    Science.gov (United States)

    Pourquier, Philippe

    2011-11-01

    With the approval of mechlorethamine by the FDA in 1949 for the treatment of hematologic malignancies, alkylating agents are the oldest class of anticancer agents. Even though their clinical use is far beyond the use of new targeted therapies, they still occupy a major place in specific indications and sometimes represent the unique option for the treatment of refractory diseases. Here, we are reviewing the major classes of alkylating agents and their mechanism of action, with a particular emphasis for the new generations of alkylating agents. As for most of the chemotherapeutic agents used in the clinic, these compounds are derived from natural sources. With a complex but original mechanism of action, they represent new interesting alternatives for the clinicians, especially for tumors that are resistant to conventional DNA damaging agents. We also briefly describe the different strategies that have been or are currently developed to potentiate the use of classical alkylating agents, especially the inhibition of pathways that are involved in the repair of DNA lesions induced by these agents. In this line, the development of PARP inhibitors is a striking example of the recent regain of interest towards the "old" alkylating agents.

  7. Labelled chemotherapeutic drugs and neurotransmitter precursors

    International Nuclear Information System (INIS)

    Diksic, M.

    1989-01-01

    The authors have synthesized several chemotherapeutic drugs and their analogs labelled with 11 C or 18 F positron emitting radionuclides. The pharmacokinetics of several of these, 1,3-bis-2-chloroethylnitroso [ 11 C] urea [ 11 C-BCNU] and sarcosinamide congenerate of BCNU [SarCNU] were studied in animals and humans. This evaluation permitted them to have a better understanding of the tissue trapping of nitrosoureas and also the opportunity to do biological modelling permitting a better schedule of chemotherapy for these drugs. They have also been working on an analog of tryptophan, α-methyl-L-tryptophan, the compound studied for the past 15 years. An introduction of 11 C-label permitted in vivo evaluation of that compound and in conjunction with biochemical measurements done with 14 C-compound estimates of the rate of the brain serotonin synthesis without any metabolic manipulation

  8. Molecular cloning and characterization of taurocyamine kinase from Clonorchis sinensis: a candidate chemotherapeutic target.

    Directory of Open Access Journals (Sweden)

    Jing-Ying Xiao

    2013-11-01

    Full Text Available BACKGROUND: Adult Clonorchis sinensis lives in the bile duct and causes endemic clonorchiasis in East Asian countries. Phosphagen kinases (PK constitute a highly conserved family of enzymes, which play a role in ATP buffering in cells, and are potential targets for chemotherapeutic agents, since variants of PK are found only in invertebrate animals, including helminthic parasites. This work is conducted to characterize a PK from C. sinensis and to address further investigation for future drug development. METHODOLOGY/PRINCIPAL FINDINGS: [corrected] A cDNA clone encoding a putative polypeptide of 717 amino acids was retrieved from a C. sinensis transcriptome. This polypeptide was homologous to taurocyamine kinase (TK of the invertebrate animals and consisted of two contiguous domains. C. sinensis TK (CsTK gene was reported and found consist of 13 exons intercalated with 12 introns. This suggested an evolutionary pathway originating from an arginine kinase gene group, and distinguished annelid TK from the general CK phylogenetic group. CsTK was found not to have a homologous counterpart in sequences analysis of its mammalian hosts from public databases. Individual domains of CsTK, as well as the whole two-domain enzyme, showed enzymatic activity and specificity toward taurocyamine substrate. Of the CsTK residues, R58, I60 and Y84 of domain 1, and H60, I63 and Y87 of domain 2 were found to participate in binding taurocyamine. CsTK expression was distributed in locomotive and reproductive organs of adult C. sinensis. Developmentally, CsTK was stably expressed in both the adult and metacercariae stages. Recombinant CsTK protein was found to have low sensitivity and specificity toward C. sinensis and platyhelminth-infected human sera on ELISA. CONCLUSION: CsTK is a promising anti-C. sinensis drug target since the enzyme is found only in the C. sinensis and has a substrate specificity for taurocyamine, which is different from its mammalian counterpart

  9. Molecular Cloning and Characterization of Taurocyamine Kinase from Clonorchis sinensis: A Candidate Chemotherapeutic Target

    Science.gov (United States)

    Tokuhiro, Shinji; Nagataki, Mitsuru; Jarilla, Blanca R.; Nomura, Haruka; Kim, Tae Im; Hong, Sung-Jong; Agatsuma, Takeshi

    2013-01-01

    Background Adult Clonorchis sinensis lives in the bile duct and causes endemic clonorchiasis in East Asian countries. Phosphagen kinases (PK) constitute a highly conserved family of enzymes, which play a role in ATP buffering in cells, and are potential targets for chemotherapeutic agents, since variants of PK are found only in invertebrate animals, including helminthic parasites. This work is conducted to characterize a PK from C. sinensis and to address further investigation for future drug development. Methology/Principal findings A cDNA clone encoding a putative polypeptide of 717 amino acids was retrieved from a C. sinensis transcriptome. This polypeptide was homologous to taurocyamine kinase (TK) of the invertebrate animals and consisted of two contiguous domains. C. sinensis TK (CsTK) gene was reported and found consist of 13 exons intercalated with 12 introns. This suggested an evolutionary pathway originating from an arginine kinase gene group, and distinguished annelid TK from the general CK phylogenetic group. CsTK was found not to have a homologous counterpart in sequences analysis of its mammalian hosts from public databases. Individual domains of CsTK, as well as the whole two-domain enzyme, showed enzymatic activity and specificity toward taurocyamine substrate. Of the CsTK residues, R58, I60 and Y84 of domain 1, and H60, I63 and Y87 of domain 2 were found to participate in binding taurocyamine. CsTK expression was distributed in locomotive and reproductive organs of adult C. sinensis. Developmentally, CsTK was stably expressed in both the adult and metacercariae stages. Recombinant CsTK protein was found to have low sensitivity and specificity toward C. sinensis and platyhelminth-infected human sera on ELISA. Conclusion CsTK is a promising anti-C. sinensis drug target since the enzyme is found only in the C. sinensis and has a substrate specificity for taurocyamine, which is different from its mammalian counterpart, creatine. PMID:24278491

  10. Biomarker-guided repurposing of chemotherapeutic drugs for cancer therapy

    DEFF Research Database (Denmark)

    Stenvang, Jan; Kümler, Iben; Nygård, Sune Boris

    2013-01-01

    -standard chemotherapeutic drug will be relatively low in such a patient cohort it is a pre-requisite that such testing is based on predictive biomarkers. This review describes our strategy of biomarker-guided repurposing of chemotherapeutic drugs for cancer therapy, taking the repurposing of topoisomerase I (Top1...

  11. 3-Bromopyruvate (3BP) a fast acting, promising, powerful, specific, and effective "small molecule" anti-cancer agent taken from labside to bedside: introduction to a special issue.

    Science.gov (United States)

    Pedersen, Peter L

    2012-02-01

    Although the "Warburg effect", i.e., elevated glucose metabolism to lactic acid (glycolysis) even in the presence of oxygen, has been recognized as the most common biochemical phenotype of cancer for over 80 years, its biochemical and genetic basis remained unknown for over 50 years. Work focused on elucidating the underlying mechanism(s) of the "Warburg effect" commenced in the author's laboratory in 1969. By 1985 among the novel findings made two related most directly to the basis of the "Warburg effect", the first that the mitochondrial content of tumors exhibiting this phenotype is markedly decreased relative to the tissue of origin, and the second that such mitochondria have markedly elevated amounts of the enzyme hexokinase-2 (HK2) bound to their outer membrane. HK2 is the first of a number of enzymes in cancer cells involved in metabolizing the sugar glucose to lactic acid. At its mitochondrial location HK2 binds at/near the protein VDAC (voltage dependent anion channel), escapes inhibition by its product glucose-6-phosphate, and gains access to mitochondrial produced ATP. As shown by others, it also helps immortalize cancer cells, i.e., prevents cell death. Based on these studies, the author's laboratory commenced experiments to elucidate the gene basis for the overexpression of HK2 in cancer. These studies led to both the discovery of a unique HK2 promoter region markedly activated by both hypoxic conditions and moderately activated by several metabolites (e.g., glucose), Also discovered was the promoter's regulation by epigenetic events (i.e., methylation, demethylation). Finally, the author's laboratory turned to the most important objective. Could they selectively and completely destroy cancerous tumors in animals? This led to the discovery in an experiment conceived, designed, and conducted by Young Ko that the small molecule 3-bromopyruvate (3BP), the subject of this mini-review series, is an incredibly powerful and swift acting anticancer agent

  12. Promising biocidal activity of thymol loaded chitosan silver nanoparticles (T-C@AgNPs) as anti-infective agents against perilous pathogens.

    Science.gov (United States)

    Manukumar, H M; Umesha, S; Kumar, H N Naveen

    2017-09-01

    The advent of biodegradable polymer-encapsulated drug nanoparticles has made an exciting area of drug delivery research. The present study investigated novel and simple route for synthesis of thymol loaded chitosan silver nanoparticles (T-C@AgNPs) using chitosan and thymol as reducing, capping agent respectively to understand the therapeutic efficacy. The UV-vis spectroscopy, DLS, FT-IR, SEM, EDS, XRD used for characterization and radical scavenging activity, anti-microbial and biocompatibility was taken to ascertain an efficacy of novel T-C@AgNPs. The T-C@AgNPs intense peak at 490nm indicates the formation of nanoparticles and had average particle size of 28.94nm with spherical shape, monodisperse state in water, also exhibited excellent biocompatibility of cubic shaped pure silver element containing T-C@AgNPs. The antibacterial activity was studied for gram positive and gram negative food-borne pathogens and effective inhibition at 100μgmL -1 to S. aureus, S. epidermidis, S. haemolyticus (10.08, 10.00, 11.23mm) and S. typhimurium, P. aeruginosa and S. flexneri (9.28, 9.33, 12.03mm) compared to antibiotic Streptomycin. This study revealed the efficacy against multiple food-borne pathogens and therapeutic efficacy of T-C@AgNPs offers a valuable contribution in the area of nanotechnology. This proved to be a first-class novel antimicrobial material for the first time in this study. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Transient receptor potential ankyrin 1 receptor activation in vitro and in vivo by pro-tussive agents: GRC 17536 as a promising anti-tussive therapeutic.

    Directory of Open Access Journals (Sweden)

    Indranil Mukhopadhyay

    Full Text Available Cough is a protective reflex action that helps clear the respiratory tract which is continuously exposed to airborne environmental irritants. However, chronic cough presents itself as a disease in its own right and despite its global occurrence; the molecular mechanisms responsible for cough are not completely understood. Transient receptor potential ankyrin1 (TRPA1 is robustly expressed in the neuronal as well as non-neuronal cells of the respiratory tract and is a sensor of a wide range of environmental irritants. It is fast getting acceptance as a key biological sensor of a variety of pro-tussive agents often implicated in miscellaneous chronic cough conditions. In the present study, we demonstrate in vitro direct functional activation of TRPA1 receptor by citric acid which is routinely used to evoke cough in preclinical and clinical studies. We also show for the first time that a potent and selective TRPA1 antagonist GRC 17536 inhibits citric acid induced cellular Ca(+2 influx in TRPA1 expressing cells and the citric acid induced cough response in guinea pigs. Hence our data provides a mechanistic link between TRPA1 receptor activation in vitro and cough response induced in vivo by citric acid. Furthermore, we also show evidence for TRPA1 activation in vitro by the TLR4, TLR7 and TLR8 ligands which are implicated in bacterial/respiratory virus pathogenesis often resulting in chronic cough. In conclusion, this study highlights the potential utility of TRPA1 antagonist such as GRC 17536 in the treatment of miscellaneous chronic cough conditions arising due to diverse causes but commonly driven via TRPA1.

  14. Constructing aptamer anchored nanovesicles for enhanced tumor penetration and cellular uptake of water soluble chemotherapeutics.

    Science.gov (United States)

    Li, Xin; Zhu, Xiumei; Qiu, Liyan

    2016-04-15

    Polymersomes represent a promising pharmaceutical vehicle for the delivery of hydrophilic therapeutic agents. However, modification of polymersomes with molecules that confer targeting functions remains challenging because of the strict requirements regarding the weight fractions of the hydrophilic and hydrophobic block polymers. In this study, based on the compatibility between cholesterol and polymeric carriers, polymersomes self-assembled by amphiphilic graft polyphosphazenes were endowed with a targeting function by incorporating the cholesterol-linked aptamer through a simple dialysis method. The aqueous interior of the polymersomes was employed to encapsulate water-soluble doxorubicin hydrochloride. In vivo experiments in tumor-bearing mice showed that the aptamer-anchored vesicle targeted accumulation at the tumor site, favorable penetration through tumor tissue, and incremental endocytosis into tumor cells. Correspondingly, the aptamer-anchored vesicle decreased systemic toxicity and effectively suppressed the growth of subcutaneous MCF-7 xenografts. These findings suggested that vesicles modified with targeted groups via hydrophobic supermolecular interactions could provide a platform for selective delivery of hydrophilic drug. Polymersomes have represented a promising type of pharmaceutical vehicles due to their predominant physical properties. However, it is still a challenge to endow polymersomes with active target function because of strict requirements of the weight fractions of hydrophilic polymer block to hydrophobic one. In this research, by taking advantage of the supermolecular interactions between amphiphilic graft polyphosphazene and cholesterol which was linked to aptamer AS1411, we prepared a targeted functional polymersome (PEP-DOX·HCl-Ap) through a simple method with high loading of water soluble anti-cancer drug doxorubicin hydrochloride. The in vivo experiments in MCF-7 tumor-bearing mice demonstrated several advantages of PEP

  15. The electron affinity of some radiotherapeutic agents used in cancer therapy

    International Nuclear Information System (INIS)

    Wold, E.; Kaalhus, O.; Johansen, E.S.; Ekse, A.T.

    1980-01-01

    In order to evaluate whether chemotherapeutic compounds applied in cancer treatment might interact with radiation as anoxic cell sensitizers, the electron-affinic properties of DTIC (5-(3,3-dimethyl-1-triazeno)imidazole-4 carboxamide) AIC 4(5)-aminoimidazole-5(4)-carboxamide, hydroxyurea, busulfan and cyclophosphamide were studied by pulse radiolysis. Reaction rates with hydrated electrons were determined for all these compounds. With the exception of DTIC, they all reacted much more slowly with electrons than do most electron-affinic sensitizers. One-electron reduction potentials were determined for DTIC, AIC and hydroxyurea. The values were all in the region for the onset of sensitization, with hydroxyurea as the most promising (E 7 1 = -0.552 V). For busulfan and cyclophosphamide no value could be determined, but these compounds are probably less electron-affinic than hydroxyurea. A possible application of chemotherapeutic agents as radiosensitizers is discussed. (author)

  16. Could the FDA-approved anti-HIV PR inhibitors be promising anticancer agents? An answer from enhanced docking approach and molecular dynamics analyses

    Directory of Open Access Journals (Sweden)

    Arodola OA

    2015-11-01

    Full Text Available Olayide A Arodola, Mahmoud ES SolimanMolecular Modelling and Drug Design Lab, School of Health Sciences, Westville Campus, University of KwaZulu-Natal, Durban, South AfricaAbstract: Based on experimental data, the anticancer activity of nelfinavir (NFV, a US Food and Drug Administration (FDA-approved HIV-1 protease inhibitor (PI, was reported. Nevertheless, the mechanism of action of NFV is yet to be verified. It was hypothesized that the anticancer activity of NFV is due to its inhibitory effect on heat shock protein 90 (Hsp90, a promising target for anticancer therapy. Such findings prompted us to investigate the potential anticancer activity of all other FDA-approved HIV-1 PIs against human Hsp90. To accomplish this, “loop docking” – an enhanced in-house developed molecular docking approach – followed by molecular dynamic simulations and postdynamic analyses were performed to elaborate on the binding mechanism and relative binding affinities of nine FDA-approved HIV-1 PIs against human Hsp90. Due to the lack of the X-ray crystal structure of human Hsp90, homology modeling was performed to create its 3D structure for subsequent simulations. Results showed that NFV has better binding affinity (ΔG =−9.2 kcal/mol when compared with other PIs: this is in a reasonable accordance with the experimental data (IC50 3.1 µM. Indinavir, saquinavir, and ritonavir have close binding affinity to NFV (ΔG =−9.0, −8.6, and −8.5 kcal/mol, respectively. Per-residue interaction energy decomposition analysis showed that hydrophobic interaction (most importantly with Val534 and Met602 played the most predominant role in drug binding. To further validate the docking outcome, 5 ns molecular dynamic simulations were performed in order to assess the stability of the docked complexes. To our knowledge, this is the first account of detailed computational investigations aimed to investigate the potential anticancer activity and the binding

  17. Uptake of {sup 99m}Tc-labeled chondroitin sulfate by chondrocytes and cartilage: a promising agent for imaging of cartilage degeneration?

    Energy Technology Data Exchange (ETDEWEB)

    Sobal, Grazyna [Department of Nuclear Medicine, Medical University of Vienna, Vienna 1090 (Austria)], E-mail: grazyna.sobal@meduniwien.ac.at; Menzel, Johannes [Institute of Immunology, Medical University of Vienna, Vienna 1090 (Austria); Sinzinger, Helmut [Department of Nuclear Medicine, Medical University of Vienna, Vienna 1090 (Austria)

    2009-01-15

    of in vitro cartilage tissue uptake. These data show that {sup 99m}TcCS accumulates in cartilage tissue, either by acting as a substrate for proteoglycan synthesis or by adsorption to cartilage. {sup 99m}TcCS could therefore be a possible agent to target and radioimage osteoarthritis.

  18. Chemotherapeutic prevention studies of prostate cancer

    DEFF Research Database (Denmark)

    Djavan, Bob; Zlotta, Alexandre; Schulman, Claude

    2004-01-01

    Despite advances in the detection and management of prostate cancer, this disease remains a major cause of morbidity and mortality in men. Increasing attention has focused on the role of chemoprevention for prostate cancer, ie the administration of agents that inhibit 1 or more steps in the natural...... history of prostate carcinogenesis. We review prostate cancer chemoprevention studies in Europe....

  19. Chemotherapeutic drugs sensitize human renal cell carcinoma cells to ABT-737 by a mechanism involving the Noxa-dependent inactivation of Mcl-1 or A1

    Directory of Open Access Journals (Sweden)

    Zantl Niko

    2010-06-01

    Full Text Available Abstract Background Human renal cell carcinoma (RCC is very resistant to chemotherapy. ABT-737 is a novel inhibitor of anti-apoptotic proteins of the Bcl-2 family that has shown promise in various preclinical tumour models. Results We here report a strong over-additive pro-apoptotic effect of ABT-737 and etoposide, vinblastine or paclitaxel but not 5-fluorouracil in cell lines from human RCC. ABT-737 showed very little activity as a single agent but killed RCC cells potently when anti-apoptotic Mcl-1 or, unexpectedly, A1 was targeted by RNAi. This potent augmentation required endogenous Noxa protein since RNAi directed against Noxa but not against Bim or Puma reduced apoptosis induction by the combination of ABT-737 and etoposide or vinblastine. At the level of mitochondria, etoposide-treatment had a similar sensitizing activity and allowed for ABT-737-induced release of cytochrome c. Conclusions Chemotherapeutic drugs can overcome protection afforded by Mcl-1 and A1 through endogenous Noxa protein in RCC cells, and the combination of such drugs with ABT-737 may be a promising strategy in RCC. Strikingly, A1 emerged in RCC cell lines as a protein of similar importance as the well-established Mcl-1 in protection against apoptosis in these cells.

  20. Cytotoxic effects of chemotherapeutic drugs and heterocyclic compounds at application on the cells of primary culture of neuroepithelium tumors.

    Science.gov (United States)

    Kulchitsky, Vladimir A; Potkin, Vladimir I; Zubenko, Yuri S; Chernov, Alexander N; Talabaev, Michael V; Demidchik, Yuri E; Petkevich, Sergei K; Kazbanov, Vladimir V; Gurinovich, Tatiana A; Roeva, Margarita O; Grigoriev, Dmitry G; Kletskov, Alexei V; Kalunov, Vladimir N

    2012-01-01

    Neuroepithelial tumor cells were cultured in vitro. The biopsy material was taken from 93 children at removal of the brain tumors during neurosurgical operations. The individual features of the cells sensitivity of primary cultures in respect to protocol-approved chemotherapy drugs and changes in the Interleukin-6 (Il-6) level in the culture medium after the application of chemotherapy were established. The initial level of Il-6 exceeded 600.0 pg/ml in the cultural medium with histologically verified pilomyxoid astrocytoma cells, and ranged from 100.0 to 200.0 pg/ml in the medium at cultivation of ganglioneuroblastoma and pilocytic astrocytoma. A decrease in the Il-6 level in the medium culture of primary tumors cells was observed after the application of chemotherapeutic agents on the cells of pilomyxoid astrocytoma, astrocytomas, and pilocytic desmoplastic/nodular medulloblastoma. The production of Il-6 increased after application of cytostatic drugs on the cells of oligoastrocytomas. A decrease in Il-6 level after application of Cisplatin and Methotrexate and a 5-10 fold increase in the level of Il-6 after application of Etoposide, Carboplatin, Cytarabine, and Gemcitabine were registered in the medium with ganglioneuroblastoma. To improve the cytotoxic action of chemotherapeutic agents, the combined application of cytostatics with heterocyclic compounds was carried out. A computer modeling of ligand-protein complexes of carbamide using the Dock 6.4 and USF Chimera program packages was performed with molecular mechanics method. Special attention was drawn to the ability of several isoxazole heterocycles and isothiazolyl to inhibit the tyrosine kinase. It was proved in vitro that the joint application of chemotherapeutic agents and heterocyclic compounds could reduce the concentration of the cytostatic factor by 10 or more times, having maintained the maximum cytotoxic effect. It was assumed that the target amplification of cytotoxic action of chemotherapeutic

  1. Oncolytic herpes viruses, chemotherapeutics, and other cancer drugs

    Directory of Open Access Journals (Sweden)

    Braidwood L

    2013-12-01

    Full Text Available Lynne Braidwood,1 Sheila V Graham,2 Alex Graham,1 Joe Conner11Virttu Biologics Ltd, Department of Neurology, Southern General Hospital, Glasgow, UK; 2MRC-University of Glasgow Centre for Virus Research, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Jarrett Building, University of Glasgow, Glasgow, UKAbstract: Oncolytic viruses are emerging as a potential new way of treating cancers. They are selectively replication-competent viruses that propagate only in actively dividing tumor cells but not in normal cells and, as a result, destroy the tumor cells by consequence of lytic infection. At least six different oncolytic herpes simplex viruses (oHSVs have undergone clinical trials worldwide to date, and they have demonstrated an excellent safety profile and intimations of efficacy. The first pivotal Phase III trial with an oHSV, talimogene laherparepvec (T-Vec [OncoVexGM-CSF], is almost complete, with extremely positive early results reported. Intuitively, therapeutically beneficial interactions between oHSV and chemotherapeutic and targeted therapeutic drugs would be limited as the virus requires actively dividing cells for maximum replication efficiency and most anticancer agents are cytotoxic or cytostatic. However, combinations of such agents display a range of responses, with antagonistic, additive, or, perhaps most surprisingly, synergistic enhancement of antitumor activity. When synergistic interactions in cancer cell killing are observed, chemotherapy dose reductions that achieve the same overall efficacy may be possible, resulting in a valuable reduction of adverse side effects. Therefore, the combination of an oHSV with “standard-of-care” drugs makes a logical and reasonable approach to improved therapy, and the addition of a targeted oncolytic therapy with “standard-of-care” drugs merits further investigation, both preclinically and in the clinic. Numerous publications report

  2. An integrated approach to the prediction of chemotherapeutic response in patients with breast cancer.

    Directory of Open Access Journals (Sweden)

    Kelly H Salter

    Full Text Available A major challenge in oncology is the selection of the most effective chemotherapeutic agents for individual patients, while the administration of ineffective chemotherapy increases mortality and decreases quality of life in cancer patients. This emphasizes the need to evaluate every patient's probability of responding to each chemotherapeutic agent and limiting the agents used to those most likely to be effective.Using gene expression data on the NCI-60 and corresponding drug sensitivity, mRNA and microRNA profiles were developed representing sensitivity to individual chemotherapeutic agents. The mRNA signatures were tested in an independent cohort of 133 breast cancer patients treated with the TFAC (paclitaxel, 5-fluorouracil, adriamycin, and cyclophosphamide chemotherapy regimen. To further dissect the biology of resistance, we applied signatures of oncogenic pathway activation and performed hierarchical clustering. We then used mRNA signatures of chemotherapy sensitivity to identify alternative therapeutics for patients resistant to TFAC. Profiles from mRNA and microRNA expression data represent distinct biologic mechanisms of resistance to common cytotoxic agents. The individual mRNA signatures were validated in an independent dataset of breast tumors (P = 0.002, NPV = 82%. When the accuracy of the signatures was analyzed based on molecular variables, the predictive ability was found to be greater in basal-like than non basal-like patients (P = 0.03 and P = 0.06. Samples from patients with co-activated Myc and E2F represented the cohort with the lowest percentage (8% of responders. Using mRNA signatures of sensitivity to other cytotoxic agents, we predict that TFAC non-responders are more likely to be sensitive to docetaxel (P = 0.04, representing a viable alternative therapy.Our results suggest that the optimal strategy for chemotherapy sensitivity prediction integrates molecular variables such as ER and HER2 status with corresponding micro

  3. Rapid selection and proliferation of CD133+ cells from cancer cell lines: chemotherapeutic implications.

    Directory of Open Access Journals (Sweden)

    Sarah E Kelly

    2010-04-01

    Full Text Available Cancer stem cells (CSCs are considered a subset of the bulk tumor responsible for initiating and maintaining the disease. Several surface cellular markers have been recently used to identify CSCs. Among those is CD133, which is expressed by hematopoietic progenitor cells as well as embryonic stem cells and various cancers. We have recently isolated and cultured CD133 positive [CD133+] cells from various cancer cell lines using a NASA developed Hydrodynamic Focusing Bioreactor (HFB (Celdyne, Houston, TX. For comparison, another bioreactor, the rotary cell culture system (RCCS manufactured by Synthecon (Houston, TX was used. Both the HFB and the RCCS bioreactors simulate aspects of hypogravity. In our study, the HFB increased CD133+ cell growth from various cell lines compared to the RCCS vessel and to normal gravity control. We observed a +15-fold proliferation of the CD133+ cellular fraction with cancer cells that were cultured for 7-days at optimized conditions. The RCCS vessel instead yielded a (-4.8-fold decrease in the CD133+cellular fraction respect to the HFB after 7-days of culture. Interestingly, we also found that the hypogravity environment of the HFB greatly sensitized the CD133+ cancer cells, which are normally resistant to chemo treatment, to become susceptible to various chemotherapeutic agents, paving the way to less toxic and more effective chemotherapeutic treatment in patients. To be able to test the efficacy of cytotoxic agents in vitro prior to their use in clinical setting on cancer cells as well as on cancer stem cells may pave the way to more effective chemotherapeutic strategies in patients. This could be an important advancement in the therapeutic options of oncologic patients, allowing for more targeted and personalized chemotherapy regimens as well as for higher response rates.

  4. Development of a novel, physiologically relevant cytotoxicity model: Application to the study of chemotherapeutic damage to mesenchymal stromal cells

    Energy Technology Data Exchange (ETDEWEB)

    May, Jennifer E., E-mail: Jennifer2.May@uwe.ac.uk; Morse, H. Ruth, E-mail: Ruth.Morse@uwe.ac.uk; Xu, Jinsheng, E-mail: Jinsheng.Xu@uwe.ac.uk; Donaldson, Craig, E-mail: Craig.Donaldson@uwe.ac.uk

    2012-09-15

    There is an increasing need for development of physiologically relevant in-vitro models for testing toxicity, however determining toxic effects of agents which undergo extensive hepatic metabolism can be particularly challenging. If a source of such metabolic enzymes is inadequate within a model system, toxicity from prodrugs may be grossly underestimated. Conversely, the vast majority of agents are detoxified by the liver, consequently toxicity from such agents may be overestimated. In this study we describe the development of a novel in-vitro model, which could be adapted for any toxicology setting. The model utilises HepG2 liver spheroids as a source of metabolic enzymes, which have been shown to more closely resemble human liver than traditional monolayer cultures. A co-culture model has been developed enabling the effect of any metabolised agent on another cell type to be assessed. This has been optimised to enable the study of damaging effects of chemotherapy on mesenchymal stem cells (MSC), the supportive stem cells of the bone marrow. Several optimisation steps were undertaken, including determining optimal culture conditions, confirmation of hepatic P450 enzyme activity and ensuring physiologically relevant doses of chemotherapeutic agents were appropriate for use within the model. The developed model was subsequently validated using several chemotherapeutic agents, both prodrugs and active drugs, with resulting MSC damage closely resembling effects seen in patients following chemotherapy. Minimal modifications would enable this novel co-culture model to be utilised as a general toxicity model, contributing to the drive to reduce animal safety testing and enabling physiologically relevant in-vitro study. -- Highlights: ► An in vitro model was developed for study of drugs requiring hepatic metabolism ► HepG2 spheroids were utilised as a physiologically relevant source of liver enzymes ► The model was optimised to enable study of chemotherapeutic

  5. Development of a novel, physiologically relevant cytotoxicity model: Application to the study of chemotherapeutic damage to mesenchymal stromal cells

    International Nuclear Information System (INIS)

    May, Jennifer E.; Morse, H. Ruth; Xu, Jinsheng; Donaldson, Craig

    2012-01-01

    There is an increasing need for development of physiologically relevant in-vitro models for testing toxicity, however determining toxic effects of agents which undergo extensive hepatic metabolism can be particularly challenging. If a source of such metabolic enzymes is inadequate within a model system, toxicity from prodrugs may be grossly underestimated. Conversely, the vast majority of agents are detoxified by the liver, consequently toxicity from such agents may be overestimated. In this study we describe the development of a novel in-vitro model, which could be adapted for any toxicology setting. The model utilises HepG2 liver spheroids as a source of metabolic enzymes, which have been shown to more closely resemble human liver than traditional monolayer cultures. A co-culture model has been developed enabling the effect of any metabolised agent on another cell type to be assessed. This has been optimised to enable the study of damaging effects of chemotherapy on mesenchymal stem cells (MSC), the supportive stem cells of the bone marrow. Several optimisation steps were undertaken, including determining optimal culture conditions, confirmation of hepatic P450 enzyme activity and ensuring physiologically relevant doses of chemotherapeutic agents were appropriate for use within the model. The developed model was subsequently validated using several chemotherapeutic agents, both prodrugs and active drugs, with resulting MSC damage closely resembling effects seen in patients following chemotherapy. Minimal modifications would enable this novel co-culture model to be utilised as a general toxicity model, contributing to the drive to reduce animal safety testing and enabling physiologically relevant in-vitro study. -- Highlights: ► An in vitro model was developed for study of drugs requiring hepatic metabolism ► HepG2 spheroids were utilised as a physiologically relevant source of liver enzymes ► The model was optimised to enable study of chemotherapeutic

  6. The Paracrine Induction of TRAIL by Genotoxic Agents

    National Research Council Canada - National Science Library

    Spalding, Aaron

    2002-01-01

    TNF related apoptosis inducing ligand, TRAIL, is a recently cloned cytokine that has been shown to induce apoptosis in a synergistic fashion with chemotherapeutic agents on several cancer cell lines...

  7. [Chemotherapeutic characterization of new nitrosourea compounds].

    Science.gov (United States)

    Zeller, W J; Berger, M R; Eisenbrand, G; Petru, E

    1988-01-01

    The development of new nitrosoureas is described using selected examples. Results obtained with water-soluble analogs and with compounds linked to biomolecules as for instance amino acids, oligopeptides and steroids, are presented. The pronounced antineoplastic effect of some water-soluble analogs is paralleled by an increased rate of DNA-interstrand cross-links and by an increased suppression of hematopoietic stem cells. The suppression of bone marrow stem cells is followed by their rapid regeneration. Water-soluble nitrosoureas induce significant less inhibition of glutathione reductase as compared with established compounds. With regard to long-term toxicity and carcinogenicity water-soluble are superior to established compounds as for instance BCNU. Linking of the nitrosourea moiety to amino acids and oligopeptides led to some analogs with outstanding therapeutic ratio. Out of a group of steroid-linked nitrosoureas, CNC-L-alanine-estradiol-17-ester (CNC-ala-17-E2) is chosen to demonstrate the possibility of reducing bone marrow toxicity despite unchanged or increased therapeutic activity by attachment of the nitrosourea moiety to a steroid. Results of a comparative interspecies in vitro evaluation of CNC-ala-17-E2 in transplanted MXT mammary carcinoma of the mouse, MNU-induced autochthonous rat mammary carcinoma and primary human mammary carcinomas are presented and the question is discussed to what extent in vitro activity of such receptor agents using the tumor stem cell assay reflects their in vivo activity.

  8. Chemotherapeutic drug delivery by tumoral extracellular matrix targeting

    NARCIS (Netherlands)

    Raavé , R.; Kuppevelt, T.H. van; Daamen, W.F.

    2018-01-01

    Systemic chemotherapy is a primary strategy in the treatment of cancer, but comes with a number of limitations such as toxicity and unfavorable biodistribution. To overcome these issues, numerous targeting systems for specific delivery of chemotherapeutics to tumor cells have been designed and

  9. Identification, synthesis, and biological evaluation of the metabolites of 3-amino-6-(3'-aminopropyl)-5H-indeno[1,2-c]isoquinoline-5,11-(6H)dione (AM6-36), a promising rexinoid lead compound for the development of cancer chemotherapeutic and chemopreventive agents.

    Science.gov (United States)

    Chen, Lian; Conda-Sheridan, Martin; Reddy, P V Narasimha; Morrell, Andrew; Park, Eun-Jung; Kondratyuk, Tamara P; Pezzuto, John M; van Breemen, Richard B; Cushman, Mark

    2012-06-28

    Activation of the retinoid X receptor (RXR), which is involved in cell proliferation, differentiation, and apoptosis, is a strategy for cancer chemotherapy and chemoprevention, and 3-amino-6-(3'-aminopropyl)-5H-indeno[1,2-c]isoquinoline-5,11-(6H)dione (AM6-36) (3) is among the few RXR ligands known. The presently reported studies of 3 include its binding to human plasma proteins, metabolic stability using human liver microsomes, metabolism by human liver microsomes and hepatocytes, and in vivo disposition in rat serum, liver, and mammary tissue. Compound 3 was 75% bound to human plasma proteins, and its metabolic stability was much greater than propranolol. One phase I metabolite was formed by human liver microsomes, seven phase I and II metabolites were formed by human hepatocytes, and five metabolites were detected in rat serum and liver after oral administration. The putative metabolites predicted using LC-MS-MS were synthesized to confirm their structures and to provide sufficient material for investigation of induction of RXRE transcriptional activity and inhibition of NFκB.

  10. Hyperthermia and chemotherapy agent

    International Nuclear Information System (INIS)

    Roizin-Towle, L.; Hall, E.J.

    1981-01-01

    The use of chemotherapeutic agents for the treatment of cancer dates back to the late 19th century, but the modern era of chemotherapy drugs was ushered in during the 1940's with the development of the polyfunctional alkylating agent. Since then, numerous classes of drugs have evolved and the combined use of antineoplastic agents with other treatment modalities such as radiation or heat, remains a large relatively unexplored area. This approach, combining local hyperthermia with chemotherapy agents affords a measure of targeting and selective toxicity not previously available for drugs. In this paper, the effects of adriamycin, bleomycin and cis-platinum are examined. The adjuvant use of heat may also reverse the resistance of hypoxic cells noted for some chemotherapy agents

  11. Probing vibrational activities, electronic properties, molecular docking and Hirshfeld surfaces analysis of 4-chlorophenyl ({[(1E)-3-(1H-imidazol-1-yl)-1-phenylpropylidene]amino}oxy)methanone: A promising anti-Candida agent

    Science.gov (United States)

    Jayasheela, K.; Al-Wahaibi, Lamya H.; Periandy, S.; Hassan, Hanan M.; Sebastian, S.; Xavier, S.; Daniel, Joseph C.; El-Emam, Ali A.; Attia, Mohamed I.

    2018-05-01

    The promising anti-Candida agent, 4-chlorophenyl ({[1E-3(1H-imidazole-1-yl)-1-phenylpropylidene}oxy)methanone (4-CPIPM) was comprehensively characterized by FT-IR, FT-Raman, UV, as well as 1H and 13C spectroscopic techniques. The theoretical calculations in the current study utilized Gaussian 09 W software with DFT approach of the B3LYP/6-311++G(d,p) method. The experimental X-ray diffraction data of the 4-CPIPM molecule were compared with the optimized structure and showed well agreement. Intermolecular electronic interactions and their stabilization energies have been analyzed by natural bond orbital method. Potential energy distribution confirmed the normal fundamental mode of vibration with the aid of MOLVIB software. The chemical shift values of the 1H and 13C spectra of the title compound were computed using gauge independent atomic orbital and the results were compared with the experimental values. The time-dependent density function theory method was used to predict the electronic, absorption wavelength and frontier molecular orbital energies. The HOMO-LUMO plots proved the charge transfer in the molecular system of the title compound through conjugated paths. The molecular electrostatic potential analysis provided the electrophilic and nucleophilic reactive sites in the title molecule which have been analyzed using Hirshfeld surface and two dimensions fingerprint plots. Non covalent interactions were also studied using reduced density gradient analysis and color filled electron density diagram. Molecular docking studies of the ligand-protein interactions along with their binding energies were carried out aiming to explain the potent anti-Candida activity of the title molecule.

  12. Strategies for improving chemotherapeutic delivery to solid tumors mediated by vascular permeability modulation

    Science.gov (United States)

    Roy Chaudhuri, Tista

    An essential mode of distribution of blood-borne chemotherapeutic agents within a solid tumor is via the micro-circulation. Poor tumor perfusion, because of a lack of functional vasculature or a lack of microvessels, as well as low tumor vascular permeability, can prevent adequate deposition of even low molecular-weight agents into the tumor. The modulation of tumor vascular function and density can provides numerous strategies for improving intratumor deposition of chemotherapeutic agents. Here we investigated strategies to improve drug delivery to two tumor types that share in common poor drug delivery, but differ in the underlying cause. First, in an angiogenesis-driven brain tumor model of Glioblastoma, the vascular permeability barrier, along with poorly-functional vasculature, hinders drug delivery. A strategy of nanoparticle-based tumor 'priming' to attack the vascular permeability barrier, employing sterically stabilized liposomal doxorubicin (SSL-DXR), was investigated. Functional and histological evaluation of tumor vasculature revealed that after an initial period of depressed vascular permeability and vascular pruning 3--4 days after SSL-DXR administration, vascular permeability and perfusion were restored and then elevated after 5--7 days. As a result of tumor priming, deposition of subsequently-administered nanoparticles was enhanced, and the efficacy of temozolomide (TMZ), if administered during the window of elevated permeability, was increased. The sequenced regimen resulted in a persistent reduction of the tumor proliferative index and a 40% suppression of tumor volume, compared to animals that received both agents simultaneously. Second, in a hypovascular, pancreatic ductal adenocarcinoma model, disruption of tumor-stromal communication via sonic hedgehog (sHH) signaling pathway inhibition mediated an indirect vascular proliferation and a more than 2-fold increase in intratumor nanoparticle deposition. Enhanced delivery of SSL-DXR in tumors pre

  13. Delivery of chemotherapeutic drugs in tumour cell-derived microparticles.

    Science.gov (United States)

    Tang, Ke; Zhang, Yi; Zhang, Huafeng; Xu, Pingwei; Liu, Jing; Ma, Jingwei; Lv, Meng; Li, Dapeng; Katirai, Foad; Shen, Guan-Xin; Zhang, Guimei; Feng, Zuo-Hua; Ye, Duyun; Huang, Bo

    2012-01-01

    Cellular microparticles are vesicular plasma membrane fragments with a diameter of 100-1,000 nanometres that are shed by cells in response to various physiological and artificial stimuli. Here we demonstrate that tumour cell-derived microparticles can be used as vectors to deliver chemotherapeutic drugs. We show that tumour cells incubated with chemotherapeutic drugs package these drugs into microparticles, which can be collected and used to effectively kill tumour cells in murine tumour models without typical side effects. We describe several mechanisms involved in this process, including uptake of drug-containing microparticles by tumour cells, synthesis of additional drug-packaging microparticles by these cells that contribute to the cytotoxic effect and the inhibition of drug efflux from tumour cells. This study highlights a novel drug delivery strategy with potential clinical application.

  14. Root Canal Irrigation: Chemical Agents and Plant Extracts Against Enterococcus faecalis

    Science.gov (United States)

    Borzini, Letizia; Condò, Roberta; De Dominicis, Paolo; Casaglia, Adriano; Cerroni, Loredana

    2016-01-01

    Background: There are various microorganisms related to intra and extra-radicular infections and many of these are involved in persistent infections. Bacterial elimination from the root canal is achieved by means of the mechanical action of instruments and irrigation as well as the antibacterial effects of the irrigating solutions. Enterococcus faecalis can frequently be isolated from root canals in cases of failed root canal treatments. Antimicrobial agents have often been developed and optimized for their activity against endodontic bacteria. An ideal root canal irrigant should be biocompatible, because of its close contact with the periodontal tissues during endodontic treatment. Sodium hypoclorite (NaOCl) is one of the most widely recommended and used endodontic irrigants but it is highly toxic to periapical tissues. Objectives: To analyze the literature on the chemotherapeutic agent and plant extracts studied as root canal irrigants. In particularly, the study is focused on their effect on Enterococcus faecalis. Method: Literature search was performed electronically in PubMed (PubMed Central, MEDLINE) for articles published in English from 1982 to April 2015. The searched keywords were “endodontic irrigants” and “Enterococcus faecalis” and “essential oil” and “plant extracts”. Results: Many of the studied chemotherapeutic agents and plant extracts have shown promising results in vitro. Conclusion: Some of the considered phytotherapic substances, could be a potential alternative to NaOCl for the biomechanical treatment of the endodontic space. PMID:28217184

  15. Fresh garlic extract inhibits Staphylococcus aureus biofilm formation under chemopreventive and chemotherapeutic conditions

    Directory of Open Access Journals (Sweden)

    Panan Ratthawongjirakul

    2016-08-01

    Full Text Available Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA are the leading aetiological pathogens of nosocomial infections worldwide. These bacteria form biofilms on both biotic and abiotic surfaces causing biofilm-associated infections. Within the biofilm, these bacteria might develop persistent and antimicrobial resistant characteristics resulting in chronic infections and treatment failures. Garlic exhibits broad pharmaceutical properties and inhibitory activities against S. aureus. We investigated the effects of aqueous fresh garlic extract on biofilm formation in S. aureus ATCC25923 and MRSA strains under chemopreventive and chemotherapeutic conditions. The viable bacteria and biofilm levels were quantified through colony count and crystal violet staining, respectively. The use of fresh garlic extract under both conditions significantly inhibited biofilm formation in S. aureus strains ATCC25923 and MRSA. Garlic could be developed as either a prophylactic or therapeutic agent to manage S. aureus biofilm-associated infections.

  16. Sensitivity to TOP2 targeting chemotherapeutics is regulated by Oct1 and FILIP1L.

    Directory of Open Access Journals (Sweden)

    Huarui Lu

    Full Text Available Topoisomerase II (TOP2 targeting drugs like doxorubicin and etoposide are frontline chemotherapeutics for a wide variety of solid and hematological malignancies, including breast and ovarian adenocarcinomas, lung cancers, soft tissue sarcomas, leukemias and lymphomas. These agents cause a block in DNA replication leading to a pronounced DNA damage response and initiation of apoptotic programs. Resistance to these agents is common, however, and elucidation of the mechanisms causing resistance to therapy could shed light on strategies to reduce the frequency of ineffective treatments. To explore these mechanisms, we utilized an unbiased shRNA screen to identify genes that regulate cell death in response to doxorubicin treatment. We identified the Filamin A interacting protein 1-like (FILIP1L gene as a crucial mediator of apoptosis triggered by doxorubicin. FILIP1L shares significant similarity with bacterial SbcC, an ATPase involved in DNA repair. FILIP1L was originally described as DOC1, or "down-regulated in ovarian cancer" and has since been shown to be downregulated in a wide variety of human tumors. FILIP1L levels increase markedly through transcriptional mechanisms following treatment with doxorubicin and other TOP2 poisons, including etoposide and mitoxantrone, but not by the TOP2 catalytic inhibitors merbarone or dexrazoxane (ICRF187, or by UV irradiation. This induction requires the action of the OCT1 transcription factor, which relocalizes to the FILIP1L promoter and facilitates its expression following doxorubicin treatment. Our findings suggest that the FILIP1L expression status in tumors may influence the response to anti-TOP2 chemotherapeutics.

  17. Cdt1 is differentially targeted for degradation by anticancer chemotherapeutic drugs.

    Directory of Open Access Journals (Sweden)

    Athanasia Stathopoulou

    Full Text Available BACKGROUND: Maintenance of genome integrity is crucial for the propagation of the genetic information. Cdt1 is a major component of the pre-replicative complex, which controls once per cell cycle DNA replication. Upon DNA damage, Cdt1 is rapidly targeted for degradation. This targeting has been suggested to safeguard genomic integrity and prevent re-replication while DNA repair is in progress. Cdt1 is deregulated in tumor specimens, while its aberrant expression is linked with aneuploidy and promotes tumorigenesis in animal models. The induction of lesions in DNA is a common mechanism by which many cytotoxic anticancer agents operate, leading to cell cycle arrest and apoptosis. METHODOLOGY/PRINCIPAL FINDING: In the present study we examine the ability of several anticancer drugs to target Cdt1 for degradation. We show that treatment of HeLa and HepG2 cells with MMS, Cisplatin and Doxorubicin lead to rapid proteolysis of Cdt1, whereas treatment with 5-Fluorouracil and Tamoxifen leave Cdt1 expression unaffected. Etoposide affects Cdt1 stability in HepG2 cells and not in HeLa cells. RNAi experiments suggest that Cdt1 proteolysis in response to MMS depends on the presence of the sliding clamp PCNA. CONCLUSION/SIGNIFICANCE: Our data suggest that treatment of tumor cells with commonly used chemotherapeutic agents induces differential responses with respect to Cdt1 proteolysis. Information on specific cellular targets in response to distinct anticancer chemotherapeutic drugs in different cancer cell types may contribute to the optimization of the efficacy of chemotherapy.

  18. Genome-wide local ancestry approach identifies genes and variants associated with chemotherapeutic susceptibility in African Americans.

    Directory of Open Access Journals (Sweden)

    Heather E Wheeler

    Full Text Available Chemotherapeutic agents are used in the treatment of many cancers, yet variable resistance and toxicities among individuals limit successful outcomes. Several studies have indicated outcome differences associated with ancestry among patients with various cancer types. Using both traditional SNP-based and newly developed gene-based genome-wide approaches, we investigated the genetics of chemotherapeutic susceptibility in lymphoblastoid cell lines derived from 83 African Americans, a population for which there is a disparity in the number of genome-wide studies performed. To account for population structure in this admixed population, we incorporated local ancestry information into our association model. We tested over 2 million SNPs and identified 325, 176, 240, and 190 SNPs that were suggestively associated with cytarabine-, 5'-deoxyfluorouridine (5'-DFUR-, carboplatin-, and cisplatin-induced cytotoxicity, respectively (p≤10(-4. Importantly, some of these variants are found only in populations of African descent. We also show that cisplatin-susceptibility SNPs are enriched for carboplatin-susceptibility SNPs. Using a gene-based genome-wide association approach, we identified 26, 11, 20, and 41 suggestive candidate genes for association with cytarabine-, 5'-DFUR-, carboplatin-, and cisplatin-induced cytotoxicity, respectively (p≤10(-3. Fourteen of these genes showed evidence of association with their respective chemotherapeutic phenotypes in the Yoruba from Ibadan, Nigeria (p<0.05, including TP53I11, COPS5 and GAS8, which are known to be involved in tumorigenesis. Although our results require further study, we have identified variants and genes associated with chemotherapeutic susceptibility in African Americans by using an approach that incorporates local ancestry information.

  19. Effects of chemotherapeutics on organotypic corticostriatal slice cultures identified by a panel of fluorescent and immunohistochemical markers

    DEFF Research Database (Denmark)

    Nørregaard, Annette; Jensen, Stine Skov; Kolenda, Jesper

    2012-01-01

    no toxicity was observed. Corresponding immunostaining showed loss of MAP2 and increased expression of GFAP and p25α for cultures exposed to 1,000 nM VCR. Cultures exposed to high concentrations of ACNU and IM disintegrated, leaving no tissue for histology. In conclusion, corticostriatal slice cultures...... specific neuronal and glial degeneration induced by chemotherapeutics in organotypic rat corticostriatal slice cultures. The slice cultures were exposed to the alkylating agents temozolomide (TMZ) and nimustine (ACNU), the tyrosine kinase inhibitor imatinib mesylate (IM) and the microtubule...

  20. Triacetin-based acetate supplementation as a chemotherapeutic adjuvant therapy in glioma.

    Science.gov (United States)

    Tsen, Andrew R; Long, Patrick M; Driscoll, Heather E; Davies, Matthew T; Teasdale, Benjamin A; Penar, Paul L; Pendlebury, William W; Spees, Jeffrey L; Lawler, Sean E; Viapiano, Mariano S; Jaworski, Diane M

    2014-03-15

    Cancer is associated with epigenetic (i.e., histone hypoacetylation) and metabolic (i.e., aerobic glycolysis) alterations. Levels of N-acetyl-L-aspartate (NAA), the primary storage form of acetate in the brain, and aspartoacylase (ASPA), the enzyme responsible for NAA catalysis to generate acetate, are reduced in glioma; yet, few studies have investigated acetate as a potential therapeutic agent. This preclinical study sought to test the efficacy of the food additive Triacetin (glyceryl triacetate, GTA) as a novel therapy to increase acetate bioavailability in glioma cells. The growth-inhibitory effects of GTA, compared to the histone deacetylase inhibitor Vorinostat (SAHA), were assessed in established human glioma cell lines (HOG and Hs683 oligodendroglioma, U87 and U251 glioblastoma) and primary tumor-derived glioma stem-like cells (GSCs), relative to an oligodendrocyte progenitor line (Oli-Neu), normal astrocytes, and neural stem cells (NSCs) in vitro. GTA was also tested as a chemotherapeutic adjuvant with temozolomide (TMZ) in orthotopically grafted GSCs. GTA-induced cytostatic growth arrest in vitro comparable to Vorinostat, but, unlike Vorinostat, GTA did not alter astrocyte growth and promoted NSC expansion. GTA alone increased survival of mice engrafted with glioblastoma GSCs and potentiated TMZ to extend survival longer than TMZ alone. GTA was most effective on GSCs with a mesenchymal cell phenotype. Given that GTA has been chronically administered safely to infants with Canavan disease, a leukodystrophy due to ASPA mutation, GTA-mediated acetate supplementation may provide a novel, safe chemotherapeutic adjuvant to reduce the growth of glioma tumors, most notably the more rapidly proliferating, glycolytic and hypoacetylated mesenchymal glioma tumors. © 2013 UICC.

  1. Elicited vs. voluntary promises

    NARCIS (Netherlands)

    Ismayilov, H.; Potters, Jan

    2017-01-01

    We set up an experiment with pre-play communication to study the impact of promise elicitation by trustors from trustees on trust and trustworthiness. When given the opportunity a majority of trustors solicits a promise from the trustee. This drives up the promise making rate by trustees to almost

  2. Endophytic Trichoderma gamsii YIM PH30019: a promising biocontrol agent with hyperosmolar, mycoparasitism, and antagonistic activities of induced volatile organic compounds on root-rot pathogenic fungi of Panax notoginseng

    Directory of Open Access Journals (Sweden)

    Jin-Lian Chen

    2016-10-01

    Conclusion: The results suggest that the endophytic fungus T. gamsii YIM PH30019 may have a good potential as a biological control agent against notoginseng phytodiseases and can provide a clue to further illuminate the interactions between Trichoderma and phytopathogens.

  3. Keeping the Promise

    Science.gov (United States)

    Whissemore, Tabitha

    2016-01-01

    Since its launch in September 2015, Heads Up America has collected information on nearly 125 promise programs across the country, many of which were instituted long before President Barack Obama announced the America's College Promise (ACP) plan in 2015. At least 27 new free community college programs have launched in states, communities, and at…

  4. Sensitivity to ionizing radiation and chemotherapeutic agents in gemcitabine-resistant human tumor cell lines

    International Nuclear Information System (INIS)

    Bree, Chris van; Kreder, Natasja Castro; 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-fluorouracil (5-FU), methotrexate (MTX), cytarabine (ara-C), and dFdC was measured by a proliferation assay. Radiosensitivity and radioenhancement by dFdC of this cell panel and the human ovarian carcinoma cell line A2780 and its dFdC-resistant variant AG6000 were determined by clonogenic assay. Bivariate flowcytometry was performed to study cell cycle changes. Results: In the SWg, a complete deoxycytidine kinase (dCK) deficiency was found on mRNA and protein level. This was accompanied by a 10-fold decrease in dCK activity which resulted in the >1000-fold resistance to dFdC. Sensitivity to other anti-tumor drugs was not altered, except for ara-C (>100-fold resistance). Radiosensitivity was not altered in the dFdC-resistant cell lines SWg and AG6000. High concentrations (50-100 μM dFdC) induced radioenhancement in the dFdC-resistant cell lines similar to the radioenhancement obtained at lower concentrations (10 nM dFdC) in the parental lines. An early S-phase arrest was found in all cell lines after dFdC treatment where radioenhancement was achieved. Conclusions: In the dFdC-resistant lung tumor cell line SWg, the deficiency in dCK is related to the resistance to dFdC and ara-C. No cross-resistance was observed to other anti-tumor drugs used for the treatment in lung cancer. Sensitivity to ionizing radiation was not altered in two different dFdC-resistant cell lines. Resistance to dFdC does not eliminate the ability of dFdC to sensitize cells to radiation

  5. Identification of lead chemotherapeutic agents from medicinal plants against blood flukes and whipworms.

    Science.gov (United States)

    Wangchuk, Phurpa; Giacomin, Paul R; Pearson, Mark S; Smout, Michael J; Loukas, Alex

    2016-08-30

    Schistosomiasis and trichuriasis are two of the most common neglected tropical diseases (NTD) that affect almost a billion people worldwide. There is only a limited number of effective drugs to combat these NTD. Medicinal plants are a viable source of parasiticides. In this study, we have investigated six of the 19 phytochemicals isolated from two Bhutanese medicinal plants, Corydalis crispa and Pleurospermum amabile, for their anthelmintic properties. We used the xWORM technique and Scanning Electron Microscope-based imaging to determine the activity of the compounds. Of the six compounds tested, isomyristicin and bergapten showed significant anthelmintic activity against Schistosoma mansoni and Trichuris muris with bergapten being the most efficacious compound one against both parasites (S. mansoni IC50 = 8.6 μg/mL and T. muris IC50 = 10.6 μg/mL) and also against the schistosomulum stage of S. mansoni. These two compounds induced tegumental damage to S. mansoni and affected the cuticle, bacillary bands and bacillary glands of T. muris. The efficacy against multiple phylogenetically distinct parasites and different life stages, especially the schistosomulum where praziquantel is ineffective, makes isomyristicin and bergapten novel scaffolds for broad-spectrum anthelmintic drug development that could be used for the control of helminths infecting humans and animals.

  6. Evaluation of Chemotherapeutic Agents Against Malaria, Drugs, Diet, and Biological Response Modifiers.

    Science.gov (United States)

    1991-10-29

    The oils, MCT and Miglyol , were found to be suitable placebos for fish oil. A normal chow diet (with adequate vitamin E levels) supplemented with 20...year. Co-enzyme Q10 did not act as an antioxidant like vitamin E during a malarial infection. Two oils, MCT and Miglyol , were found to be suitable...manipulation. In experiment 84 miglyol was added to a standard rodent chow diet with normal levels of vitamin E to see whether it whould interfere with the

  7. DNA repair methyltransferase (Mgmt) knockout mice are sensitive to the lethal effects of chemotherapeutic alkylating agents.

    NARCIS (Netherlands)

    B.J. Glassner (Brian); G. Weeda (Geert); J.M. Allan (James); J.L.M. Broekhof (Jose'); N.H.E. Carls (Nick); I. Donker (Ingrid); B.P. Engelward (Bevin); R.J. Hampson (Richard); R. Hersmus (Remko); M.J. Hickman (Mark); R.B. Roth (Richard); H.B. Warren (Henry); M.M. Wu (Mavis); J.H.J. Hoeijmakers (Jan); L.D. Samson (Leona)

    1999-01-01

    textabstractWe have generated mice deficient in O6-methylguanine DNA methyltransferase activity encoded by the murine Mgmt gene using homologous recombination to delete the region encoding the Mgmt active site cysteine. Tissues from Mgmt null mice displayed very low O6-methylguanine DNA

  8. Chemosensitization of Breast Cancer Cells to Chemotherapeutic Agents by 3,3’diindolylmethane (DIM)

    Science.gov (United States)

    2006-08-01

    therapies. However, further in-depth investigations are needed to establish the cause and effect relationship of survivin gene regulation and 3,3V...Basu GD, Pathangey LB, Tinder TL, et al. Cyclooxygenase-2 inhibitor induces apoptosis in breast cancer cells in an in vivo model of spontaneous

  9. Chemosensitization of Breast Cancer Cells to Chemotherapeutic Agents by 3,3’-Diindolylmethane (DIM)

    Science.gov (United States)

    2007-08-01

    therapies. However, further in-depth investigations are needed to establish the cause and effect relationship of survivin gene regulation and 3,3V...GD, Pathangey LB, Tinder TL, et al. Cyclooxygenase-2 inhibitor induces apoptosis in breast cancer cells in an in vivo model of spontaneous metastatic

  10. Effects of St. John's Wort and Vitamin E on Breast Cancer Chemotherapeutic Agents

    National Research Council Canada - National Science Library

    Branda, Richard

    2003-01-01

    .... Vitamin E and hyperforin levels in rat plasma correlated with dietary intake. There was no significant effect of vitamin E supplementation on the hematologic toxicity or survival in rats treated with a range of doxorubicin or docetaxel doses...

  11. Clinical Profile and Response to Chemotherapeutic Agents in Non-specific Urethritis

    Directory of Open Access Journals (Sweden)

    R K Pandhi

    1984-01-01

    Full Text Available The epidemiological and clinical profile of 159 patients having non-specific iiretbritis is repoed. The majority (67.39o of patients were unm and most (70.4% of the we m re in the age group of 21-30 years. The incubation period in the majority (69.2% of patients was 1-4 weeks. Almost all the (98.1% patients complained of dysuria but urethral discharge was seen only in 48.4% of patients. Out of tetracycline′s doxycline, erythromycin and cotrimoxazole tried in this study, tetracycline′s in the dosage of 2 gm/day for 3 weeks was found to give the best (90.5%′cure rate.

  12. Studies on the relationship between the cancer chemotherapeutic agent, hydroxyurea, and DNA repair in mammalian cells

    International Nuclear Information System (INIS)

    Katz, E.J.

    1988-01-01

    To examine the possibility that manipulating DNA repair might lessen drug resistance, we investigated whether depletion of the thymidine triphosphate (TTP) pool or administration of hydroxyurea could interfere with the ability of confluent normal human skin fibroblasts to repair ultraviolet irradiation-induced DNA damage. A method was developed for the quantitation of cellular TTP pools by labeling them with [ 3 H]thymidine. The addition of hydroxyurea, either simultaneously with [ 3 H]thymidine or two hours later, resulted in a dose- and time-dependent increase in the [ 3 H]TTP pool. The capacity of these cells to carry out DNA repair was quantitated by their ability to perform repair replication synthesis of DNA after exposure to ultraviolet irradiation. This radiation produces thymine dimers in DNA, which are repaired by the nucleotide excision repair pathway. The experimental protocol resulted in an 8-10-fold reduction in the [ 3 H]TTP pool. Saturating levels of DNA repair synthesis were observed under these conditions, with no further diminution of the already reduced [ 3 H]TTP pool. Repair replication and [ 3 H]TTP pool measurements were identical in cultures treated with 10 mM hydroxyurea and in those not exposed to the drug

  13. Dose banding as an alternative to body surface area-based dosing of chemotherapeutic agents

    NARCIS (Netherlands)

    E. Chatelut (Etienne); M.L. White-Koning (M.); A.H.J. Mathijssen (Ron); F. Puisset (F.); S.D. Baker (Sharyn); A. Sparreboom (Alex)

    2012-01-01

    textabstractBackground: Dose banding is a recently suggested dosing method that uses predefined ranges (bands) of body surface area (BSA) to calculate each patients dose by using a single BSA-value per band. Thus, drugs with sufficient long-term stability can be prepared in advance. The main

  14. 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

  15. 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.

  16. Investigating the Role of Celecoxib as a Chemopreventive and Chemotherapeutic Agent for Breast Cancer

    National Research Council Canada - National Science Library

    Levitt, Randy J

    2005-01-01

    .... The rationale for my proposed change was based on the recent announcement by Merck and Co. that they have pulled their COX-2 inhibitor rofecoxib off of the market due to unreasonable risks for heart attack and stroke...

  17. 1 ALPHA-Hydroxyvitamin D5 as a Chemotherapeutic and Possibly Chemopreventive Agent

    National Research Council Canada - National Science Library

    Das Gupta, Tapas K

    2004-01-01

    ...; high doses led to a hypercalcemic effect, which was reversible. In vitro studies showed that D5 has no effect on normal breast epithelial cells but induces apoptosis in breast cancer and showed apoptotic effect in fibroadenomas...

  18. 1-Alpha Hydroxyvitamin D(5) as a Chemotherapeutic and Possibly Chemopreventive Agent

    Science.gov (United States)

    2007-03-01

    GTT GCT GTT TGT TTG AC, and the antisense primer was 50-CTT CTG TGA GGC TGT TTT TG. The primer for the housekeeping gene G3PDH was purchased from...reverse-transcribed. The cDNA was ampli- fied using Taq polymerase and separated on 1.5% agarose gel. As shown in Fig. 5, the housekeeping gene G3PDH (C...control housekeeping gene. 784 G. Lazzaro et al. / European Journal of Cancer 36 (2000) 780±786 Appendix 3. Publications DAMD17-99-1-9223 – Final

  19. 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,

  20. Gold nanoparticles enhance the anti-leukemia action of a 6-mercaptopurine chemotherapeutic agent.

    Science.gov (United States)

    Podsiadlo, Paul; Sinani, Vladimir A; Bahng, Joong Hwan; Kam, Nadine Wong Shi; Lee, Jungwoo; Kotov, Nicholas A

    2008-01-15

    6-mercaptopurine and its riboside derivatives are some of the most widely utilized anti-leukemic and anti-inflammatory drugs. Their short biological half-life and severe side effects limit their use. A new delivery method for these drugs based on 4-5 nm gold nanoparticles can potentially resolve these issues. We have found substantial enhancement of the antiproliferative effect against K-562 leukemia cells of Au nanoparticles bearing 6-mercaptopurine-9-beta-d-ribofuranoside compared to the same drug in typically administered free form. The improvement was attributed to enhanced intracellular transport followed by the subsequent release in lysosomes. Enhanced activity and nanoparticle carriers will make possible the reduction of the overall concentration of the drug, renal clearance, and, thus, side effects. The nanoparticles with mercaptopurine also showed excellent stability over 1 year without loss of inhibitory activity.

  1. Nurses' Experiences in Safe Handling of Chemotherapeutic Agents: The Taiwan Case.

    Science.gov (United States)

    Chen, Hai-Chiao; Lu, Zxy-Yann Jane; Lee, Shu-Hui

    2016-01-01

    Nurses are the least compliant with the guidelines for use of personal protective equipment (PPE) among health professionals. While the literature regarding nurses not following the guidelines focuses on nonuse of PPE, the experiences of using PPE from nurses' perspectives have not been examined. The aim of this study was to explore the concerns of nurses regarding their decision to use or not to use PPE in the cultural context of Taiwan. An ethnographic design was used, and ethnographic interviews of 57 nurses working with chemotherapy for more than 2 years were conducted. The participating nurses were observed in 2 accredited medical centers with oncology care teams in Taiwan. The constant comparison method was applied for data analysis, and cultural themes were generated from all transcripts. Wearing PPE was identified as an obstacle to professional image and performance. Nurses transformed safety into efficiency and prioritized social roles over professional roles. Experienced nurses, as insiders, believed that they have gained clinical wisdom to avoid occupational exposure to chemotherapy toxicity. This study explored the characteristics of clinical wisdom regarding PPE use in the context of Taiwanese chemotherapy care. Perceived professional image, efficiency on the job, PPE cost, and hospital rules influenced the use or nonuse of PPE by oncology care nurses. Acceptable nurse-patient ratios and refraining from chemotherapy toxicity exposure for pregnant and breast-feeding women are advocated for policy making. The experiential expertise of nurses should be shared as credible evidence in developing guidelines.

  2. Evaluation of chemotherapeutic sequelae and quality of life in survivors of malignant sacrococcygeal teratoma

    NARCIS (Netherlands)

    Kremer, Marijke E B; Derikx, Joep P M; Kremer, Leontien C M; van Baren, Robertine; Heij, Hugo A.; Wijnen, Marc H W A; Wijnen, René M H; van der Zee, David C.; van Heurn, L. W Ernest

    2016-01-01

    Purpose: The impact of chemotherapeutic sequelae on long-term quality of life (QoL) for survivors of malignant sacrococcygeal teratoma (SCT) is unknown. The incidence of chemotherapeutic toxicity in patients treated for malignant SCT and possible effects on the QoL were analyzed. Methods:

  3. Local and global trust based on the concept of promises

    NARCIS (Netherlands)

    Bergstra, J.; Burgess, M.

    2009-01-01

    We use the notion of a promise to define local trust between agents possessing autonomous decision-making. An agent is trustworthy if it is expected that it will keep a promise. This definition satisfies most commonplace meanings of trust. Reputation is then an estimation of this expectation value

  4. Utilizing temporal variations in chemotherapeutic response to improve breast cancer treatment efficacy

    Directory of Open Access Journals (Sweden)

    Daniel J. McGrail

    2015-09-01

    Full Text Available Though survival rates for women with stage I breast cancer have radically improved, treatment options remain poor for the 40% of women diagnosed with later-stage disease. For these patients, improved chemotherapeutic treatment strategies are critical to eradicate any disseminated tumor cells. Despite many promising new drugs in vitro, most ultimately fail in the clinic. One aspect often lost during testing is in vivo circulation half-lives rarely exceed 24 hours, whereas in vitro studies involve drug exposure for 2-3 days. Here, we show how mimicking these exposure times alters efficacy. Next, using this model we show how drug response is highly time-dependent by extending analysis of cell viability out to two weeks. Variations in response both with feeding and time were dependent on drug mechanism of action. Finally, we show that by implementing this temporal knowledge of drug effects to optimize scheduling of drug administration we are able to regain chemosensitivity in a Carboplatin-resistant cell line.

  5. The putative role of lutein and zeaxanthin as protective agents against age-related macular degeneration: promise of molecular genetics for guiding mechanistic and translational research in the field1234

    Science.gov (United States)

    Neuringer, Martha

    2012-01-01

    Age-related macular degeneration (AMD) is the primary cause of vision loss in elderly people of western European ancestry. Genetic, dietary, and environmental factors affect tissue concentrations of macular xanthophylls (MXs) within retinal cell types manifesting AMD pathology. In this article we review the history and state of science on the putative role of the MXs (lutein, zeaxanthin, and meso-zeaxanthin) in AMD and report findings on AMD-associated genes encoding enzymes, transporters, ligands, and receptors affecting or affected by MXs. We then use this context to discuss emerging research opportunities that offer promise for meaningful investigation and inference in the field. PMID:23053548

  6. Base excision repair of chemotherapeutically-induced alkylated DNA damage predominantly causes contractions of expanded GAA repeats associated with Friedreich's ataxia.

    Directory of Open Access Journals (Sweden)

    Yanhao Lai

    Full Text Available Expansion of GAA·TTC repeats within the first intron of the frataxin gene is the cause of Friedreich's ataxia (FRDA, an autosomal recessive neurodegenerative disorder. However, no effective treatment for the disease has been developed as yet. In this study, we explored a possibility of shortening expanded GAA repeats associated with FRDA through chemotherapeutically-induced DNA base lesions and subsequent base excision repair (BER. We provide the first evidence that alkylated DNA damage induced by temozolomide, a chemotherapeutic DNA damaging agent can induce massive GAA repeat contractions/deletions, but only limited expansions in FRDA patient lymphoblasts. We showed that temozolomide-induced GAA repeat instability was mediated by BER. Further characterization of BER of an abasic site in the context of (GAA20 repeats indicates that the lesion mainly resulted in a large deletion of 8 repeats along with small expansions. This was because temozolomide-induced single-stranded breaks initially led to DNA slippage and the formation of a small GAA repeat loop in the upstream region of the damaged strand and a small TTC loop on the template strand. This allowed limited pol β DNA synthesis and the formation of a short 5'-GAA repeat flap that was cleaved by FEN1, thereby leading to small repeat expansions. At a later stage of BER, the small template loop expanded into a large template loop that resulted in the formation of a long 5'-GAA repeat flap. Pol β then performed limited DNA synthesis to bypass the loop, and FEN1 removed the long repeat flap ultimately causing a large repeat deletion. Our study indicates that chemotherapeutically-induced alkylated DNA damage can induce large contractions/deletions of expanded GAA repeats through BER in FRDA patient cells. This further suggests the potential of developing chemotherapeutic alkylating agents to shorten expanded GAA repeats for treatment of FRDA.

  7. Promise Zones for Applicants

    Data.gov (United States)

    Department of Housing and Urban Development — This tool assists applicants to HUD's Promise Zone initiative prepare data to submit with their application by allowing applicants to draw the exact location of the...

  8. The influence of toxicity constraints in models of chemotherapeutic protocol escalation

    KAUST Repository

    Boston, E. A. J.

    2011-04-06

    The prospect of exploiting mathematical and computational models to gain insight into the influence of scheduling on cancer chemotherapeutic effectiveness is increasingly being considered. However, the question of whether such models are robust to the inclusion of additional tumour biology is relatively unexplored. In this paper, we consider a common strategy for improving protocol scheduling that has foundations in mathematical modelling, namely the concept of dose densification, whereby rest phases between drug administrations are reduced. To maintain a manageable scope in our studies, we focus on a single cell cycle phase-specific agent with uncomplicated pharmacokinetics, as motivated by 5-Fluorouracil-based adjuvant treatments of liver micrometastases. In particular, we explore predictions of the effectiveness of dose densification and other escalations of the protocol scheduling when the influence of toxicity constraints, cell cycle phase specificity and the evolution of drug resistance are all represented within the modelling. For our specific focus, we observe that the cell cycle and toxicity should not simply be neglected in modelling studies. Our explorations also reveal the prediction that dose densification is often, but not universally, effective. Furthermore, adjustments in the duration of drug administrations are predicted to be important, especially when dose densification in isolation does not yield improvements in protocol outcomes. © The author 2011. Published by Oxford University Press on behalf of the Institute of Mathematics and its Applications. All rights reserved.

  9. Schiff base-Poloxamer P85 combination demonstrates chemotherapeutic effect on prostate cancer cells in vitro.

    Science.gov (United States)

    Demirci, Selami; Doğan, Ayşegül; Türkmen, Neşe Başak; Telci, Dilek; Rizvanov, Albert A; Şahin, Fikrettin

    2017-02-01

    Prostate cancer is a multistep and complicated cancer type that is regulated by androgens at the cellular level and remains the second commonest cause of death among men. Discovery and development of novel chemotherapeutic agents enabling rapid tumor cell death with minimal toxic effects to healthy tissues might greatly improve the safety of chemotherapy. The present study evaluates the anti-cancer activity of a novel heterodinuclear copper(II)Mn(II) complex (Schiff base) in combination with poly(ethylene oxide) and poly(propylene oxide) block copolymer (Pluronic) P85. We used assays for cell proliferation, apoptosis, cell migration and invasion, DNA binding and cleavage to elucidate the molecular mechanisms of action, in addition to the anti-inflammatory potency of the new combination. The combined treatment of Schiff base and P85 lead to a remarkable anti-cancer effect on prostate cancer cell lines. Cell proliferation was inhibited in Schiff base-P85 treatment. The activity of this formulation is on DNA binding and cleavage and prevents inflammation in in vitro conditions. This is the first study presenting the anti-cancer activity of the present Schiff base derivative and its combination with P85 to treat prostate cancer in vitro. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  10. Cellular robustness conferred by genetic crosstalk underlies resistance against chemotherapeutic drug doxorubicin in fission yeast.

    Directory of Open Access Journals (Sweden)

    Zoey Tay

    Full Text Available Doxorubicin is an anthracycline antibiotic that is among one of the most commonly used chemotherapeutic agents in the clinical setting. The usage of doxorubicin is faced with many problems including severe side effects and chemoresistance. To overcome these challenges, it is important to gain an understanding of the underlying molecular mechanisms with regards to the mode of action of doxorubicin. To facilitate this aim, we identified the genes that are required for doxorubicin resistance in the fission yeast Schizosaccharomyces pombe. We further demonstrated interplay between factors controlling various aspects of chromosome metabolism, mitochondrial respiration and membrane transport. In the nucleus we observed that the subunits of the Ino80, RSC, and SAGA complexes function in the similar epistatic group that shares significant overlap with the homologous recombination genes. However, these factors generally act in synergistic manner with the chromosome segregation regulator DASH complex proteins, possibly forming two major arms for regulating doxorubicin resistance in the nucleus. Simultaneous disruption of genes function in membrane efflux transport or the mitochondrial respiratory chain integrity in the mutants defective in either Ino80 or HR function resulted in cumulative upregulation of drug-specific growth defects, suggesting a rewiring of pathways that synergize only when the cells is exposed to the cytotoxic stress. Taken together, our work not only identified factors that are required for survival of the cells in the presence of doxorubicin but has further demonstrated that an extensive molecular crosstalk exists between these factors to robustly confer doxorubicin resistance.

  11. Improved Chemotherapeutic Activity by Morus alba Fruits through Immune Response of Toll-Like Receptor 4

    Directory of Open Access Journals (Sweden)

    Bo Yoon Chang

    2015-10-01

    Full Text Available Morus alba L. fruits have long been used in traditional medicine by many cultures. Their medicinal attributes include cardiovascular, hepatoprotective, neuroprotective and immunomodulatory actions. However, their mechanism of macrophage activation and anti-cancer effects remain unclear. The present study investigated the molecular mechanisms of immune stimulation and improved chemotherapeutic effect of M. alba L. fruit extract (MFE. MFE stimulated the production of cytokines, nitric oxide (NO and tumor necrosis factor-α (TNF-α and tumoricidal properties of macrophages. MFE activated macrophages through the mitogen-activated protein kinase (MAPKinase and nuclear factor-κB (NF-κB signaling pathways downstream from toll-like receptor (TLR 4. MFE was shown to exhibit cytotoxicity of CT26 cells via the activated macrophages, even though MFE did not directly affect CT26 cells. In a xenograft mouse model, MFE significantly enhanced anti-cancer activity combined with 5-fluorouracil and markedly promoted splenocyte proliferation, natural killer (NK cell activity, cytotoxic T lymphocyte (CTL activity and IFN-γ production. Immunoglobulin G (IgG antibody levels were significantly increased. These results indicate the indirect anti-cancer activity of MFE through improved immune response mediated by TLR4 signaling. M. alba L. fruit extract might be a potential anti-tumor immunomodulatory candidate chemotherapy agent.

  12. Improved Chemotherapeutic Activity by Morus alba Fruits through Immune Response of Toll-Like Receptor 4.

    Science.gov (United States)

    Chang, Bo Yoon; Kim, Seon Beom; Lee, Mi Kyeong; Park, Hyun; Kim, Sung Yeon

    2015-10-13

    Morus alba L. fruits have long been used in traditional medicine by many cultures. Their medicinal attributes include cardiovascular, hepatoprotective, neuroprotective and immunomodulatory actions. However, their mechanism of macrophage activation and anti-cancer effects remain unclear. The present study investigated the molecular mechanisms of immune stimulation and improved chemotherapeutic effect of M. alba L. fruit extract (MFE). MFE stimulated the production of cytokines, nitric oxide (NO) and tumor necrosis factor-α (TNF-α) and tumoricidal properties of macrophages. MFE activated macrophages through the mitogen-activated protein kinase (MAPKinase) and nuclear factor-κB (NF-κB) signaling pathways downstream from toll-like receptor (TLR) 4. MFE was shown to exhibit cytotoxicity of CT26 cells via the activated macrophages, even though MFE did not directly affect CT26 cells. In a xenograft mouse model, MFE significantly enhanced anti-cancer activity combined with 5-fluorouracil and markedly promoted splenocyte proliferation, natural killer (NK) cell activity, cytotoxic T lymphocyte (CTL) activity and IFN-γ production. Immunoglobulin G (IgG) antibody levels were significantly increased. These results indicate the indirect anti-cancer activity of MFE through improved immune response mediated by TLR4 signaling. M. alba L. fruit extract might be a potential anti-tumor immunomodulatory candidate chemotherapy agent.

  13. Differential impact of diverse anticancer chemotherapeutics on the Cdc25A-degradation checkpoint pathway

    International Nuclear Information System (INIS)

    Agner, Jeppe; Falck, Jacob; Lukas, Jiri; Bartek, Jiri

    2005-01-01

    When exposed to DNA-damaging insults such as ionizing radiation (IR) or ultraviolet light (UV), mammalian cells activate checkpoint pathways to halt cell cycle progression or induce cell death. Here we examined the ability of five commonly used anticancer drugs with different mechanisms of action to activate the Chk1/Chk2-Cdc25A-CDK2/cyclin E cell cycle checkpoint pathway, previously shown to be induced by IR or UV. Whereas exposure of human cells to topoisomerase inhibitors camptothecin, etoposide, or adriamycin resulted in rapid (within 1 h) activation of the pathway including degradation of the Cdc25A phosphatase and inhibition of cyclin E/CDK2 kinase activity, taxol failed to activate this checkpoint even after a prolonged treatment. Unexpectedly, although the alkylating agent cisplatin also induced degradation of Cdc25A (albeit delayed, after 8-12 h), cyclin E/CDK2 activity was elevated and DNA synthesis continued, a phenomena that correlated with increased E2F1 protein levels and consequently enhanced expression of cyclin E. These results reveal a differential impact of various classes of anticancer chemotherapeutics on the Cdc25A-degradation pathway, and indicate that the kinetics of checkpoint induction, and the relative balance of key components within the DNA damage response network may dictate whether the treated cells arrest their cell cycle progression

  14. In vivo enhancement of anticancer therapy using bare or chemotherapeutic drug-bearing nanodiamond particles

    Directory of Open Access Journals (Sweden)

    Li Y

    2014-02-01

    Full Text Available Yingqi Li,1,2 Yaoli Tong,1 Ruixia Cao,1 Zhimei Tian,2 Binsheng Yang,2 Pin Yang2 1Department of Chemistry, College of Chemistry and Chemical Engineering, 2Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Molecular Science, Shanxi University, Taiyuan, People's Republic of China Background: This study investigated the use of nanodiamond particles (NDs as a promising material for drug delivery in vivo and in vitro. Methods: HepG2 cells (a human hepatic carcinoma cell line were used to determine the characteristics of a nanodiamond-doxorubicin complex (ND-DOX when taken up by cells in vitro using laser scanning confocal microscopy and dialysis experiments. We also compared the survival rate and histopathology of tumor-bearing mice after treatment with NDs or ND-DOX in vivo. Results: In vitro investigation showed that ND-DOX has slow and sustained drug release characteristics compared with free doxorubicin. In vivo, the survival rate of tumor-bearing mice treated with ND-DOX was four times greater than that of mice treated with free doxorubicin. Interestingly, the survival rate in mice treated with NDs alone was close to that of mice treated with free doxorubicin. This indicates that treatment with ND-DOX can prolong the lifespan of tumor-bearing mice significantly compared with conventional doxorubicin and that NDs can have this effect as well. Histopathological analysis showed that neither the NDs nor ND-DOX were toxic to the kidney, liver, or spleen in contrast with the well-known toxic effects of free doxorubicin on the kidney and liver. Further, both the bare NDs and ND-DOX could suppress tumor growth effectively. Conclusion: NDs can potentially prolong survival, and ND-DOX may act as a nanodrug with promising chemotherapeutic efficacy and safety.  Keywords: nanodiamond, drug delivery, sustained release, survival rate, cancer, treatment

  15. [Biological agents].

    Science.gov (United States)

    Amano, Koichi

    2009-03-01

    There are two types of biological agents for the treatment of rheumatoid arthritis (RA); monoclonal antibodies and recombinant proteins. Among the latter, etanercept, a recombinant fusion protein of soluble TNF receptor and IgG was approved in 2005 in Japan. The post-marketing surveillance of 13,894 RA patients revealed the efficacy and safety profiles of etanercept in the Japanese population, as well as overseas studies. Abatacept, a recombinant fusion protein of CTLA4 and IgG, is another biological agent for RA. Two clinical trials disclosed the efficacy of abatacept for difficult-to-treat patients: the AIM for MTX-resistant cases and the ATTAIN for patients who are resistant to anti-TNF. The ATTEST trial suggested abatacept might have more acceptable safety profile than infliximab. These biologics are also promising for the treatment of RA for not only relieving clinical symptoms and signs but retarding structural damage.

  16. Promising More Information

    Science.gov (United States)

    2003-01-01

    When NASA needed a real-time, online database system capable of tracking documentation changes in its propulsion test facilities, engineers at Stennis Space Center joined with ECT International, of Brookfield, Wisconsin, to create a solution. Through NASA's Dual-Use Program, ECT developed Exdata, a software program that works within the company's existing Promise software. Exdata not only satisfied NASA s requirements, but also expanded ECT s commercial product line. Promise, ECT s primary product, is an intelligent software program with specialized functions for designing and documenting electrical control systems. An addon to AutoCAD software, Promis e generates control system schematics, panel layouts, bills of material, wire lists, and terminal plans. The drawing functions include symbol libraries, macros, and automatic line breaking. Primary Promise customers include manufacturing companies, utilities, and other organizations with complex processes to control.

  17. Reversible Cysteine Protease Inhibitors Show Promise for a Chagas Disease Cure

    Science.gov (United States)

    Beaulieu, Christian; Black, W. Cameron; Isabel, Elise; Vasquez-Camargo, Fabio; Nath-Chowdhury, Milli; Massé, Frédéric; Mellon, Christophe; Methot, Nathalie

    2014-01-01

    The cysteine protease cruzipain is essential for the viability, infectivity, and virulence of Trypanosoma cruzi, the causative agent of Chagas disease. Thus, inhibitors of cruzipain are considered promising anti-T. cruzi chemotherapeutic agents. Reversible cruzipain inhibitors containing a nitrile “warhead” were prepared and demonstrated 50% inhibitory concentrations (IC50s) as potent as 1 nM in baculovirus-generated cruzipain enzyme assays. In epimastigote and intracellular amastigote in vitro assays, the most potent compounds demonstrated antiparasitic behavior in the 5 to 10 μM IC50 range; however, trypomastigote production from the amastigote form was ∼90 to 95% inhibited at 2 μM. Two key compounds, Cz007 and Cz008, with IC50s of 1.1 and 1.8 nM, respectively, against the recombinant enzyme were tested in a murine model of acute T. cruzi infection, with oral dosing in chow for 28 days at doses from 3 to 50 mg/kg of body weight. At 3 mg/kg of Cz007 and 3 mg/kg of Cz008, the blood parasitemia areas under the concentration-time curves were 16% and 25% of the untreated group, respectively. At sacrifice, 24 days after immunosuppression with cyclophosphamide, parasite presence in blood, heart, and esophagus was evaluated. Based on negative quantitative PCR results in all three tissues, cure rates in surviving animals were 90% for Cz007 at 3 mg/kg, 78% for Cz008 at 3 mg/kg, and 71% for benznidazole, the control compound, at 50 mg/kg. PMID:24323474

  18. Clinical developments of chemotherapeutic nanomedicines: Polymers and liposomes for delivery of camptothecins and platinum (II) drugs

    KAUST Repository

    Kieler-Ferguson, Heidi M.; Frechet, Jean; Szoka, Francis C.

    2013-01-01

    For the past 40 years, liposomal and polymeric delivery vehicles have been studied as systems capable of modulating the cytotoxicity of small molecule chemotherapeutics, increasing tumor bearing animal survival times, and improving drug targeting

  19. Chemotherapeutic Impact Of Natural Antioxidant Flavonoids Gallic Acid Rutin Quercetin And Mannitol On Pathogenic Microbes And Their Synergistic Effect

    Directory of Open Access Journals (Sweden)

    Ganesh Ghosh

    2015-08-01

    Full Text Available Several studies suggest that natural flavonoids with antioxidants and can influence the response to chemotherapy as well as the development of adverse side effects that results from treatment with antineoplastic agents and Its prevalence over Multi drug resistant bacterial strain revived interest on Flavonoids. Synergistic effect is defined as passive interaction arises when two agents combine and together they exert an inhibitory effect that is greater than the sum of individual effect The new Synergistic therapy so that antioxidant are more effective in combination on multi drug resistant bacterial strain. Interaction between natural antioxidants and topoisomerase enzyme can be seen through Quercetin as a potent antimicrobial compound alone and in combination with other natural antioxidant like rutin. MICMBC result show antibacterial activity of the flavonoids were enhanced when used in combination against Staphylococcus aureus Bacillus cereus Bacillus subtilis Klebsiella pneumonae Escherichia coli as the test bacteria. The combination of rutin and quercetin rutin and gallic acid mannitol and gallic acid were much more effective than either flavonoid alone. Furthermore Its gave a good relation between these antioxidant compound and antimicrobial activity. Flavonoids as a chemotherapeutic agent and its Synergistic effect can be solution for various microbial disease conditions.

  20. Role of Reactive Oxygen Species and Nitric Oxide in Mediating Chemotherapeutic Drug Induced Bystander Response in Human Cancer Cells Exposed In-Vitro

    Science.gov (United States)

    Chinnadurai, Mani; Rao, Bhavna S; Deepika, Ramasamy; Paul, Solomon F.D.; Venkatachalam, Perumal

    2012-01-01

    Background The intention of cancer chemotherapy is to control the growth of cancer cells using chemical agents. However, the occurrence of second malignancies has raised concerns, leading to re-evaluation of the current strategy in use for chemotherapeutic agents. Although the mechanisms involved in second malignancy remain ambiguous, therapeutic-agent-induced non-DNA targeted effects like bystander response and genomic instability cannot be eliminated completely. Hence, Bleomycin (BLM) and Neocarzinostatin (NCS), chemotherapeutic drugs with a mode of action similar to ionizing radiation, were used to study the mechanism of bystander response in human cancer cells (A549, CCRF-CEM and HL-60) by employing co-culture methodology. Methods Bystander effect was quantified using micronucleus (MN) assay and in-situ immunofluorescence(γH2AX assay).The role of reactive oxygen species (ROS) and nitric oxide (NO) in mediating the bystander response was explored by pre-treating bystander cells with dimethylsulphoxide (DMSO) and C-PTIO respectively. Results Bystander response was observed only in CCRF-CEM and A549 cells (P bystander response on treatment with DMSO, suggests that ROS has a more significant role in mediating the bystander response.Since the possibility of the ROS and NO in mediating these bystander effect was confirmed, mechanistic control of these signaling molecules could either reduce radiation damage and potential carcinogenicity of normal tissues (by reducing bystander signaling) or maximize cell sterilization during chemotherapy (by amplifying bystander responses in tumors). PMID:29147282

  1. Modeling chemotherapeutic neurotoxicity with human induced pluripotent stem cell-derived neuronal cells.

    Directory of Open Access Journals (Sweden)

    Heather E Wheeler

    Full Text Available There are no effective agents to prevent or treat chemotherapy-induced peripheral neuropathy (CIPN, the most common non-hematologic toxicity of chemotherapy. Therefore, we sought to evaluate the utility of human neuron-like cells derived from induced pluripotent stem cells (iPSCs as a means to study CIPN. We used high content imaging measurements of neurite outgrowth phenotypes to compare the changes that occur to iPSC-derived neuronal cells among drugs and among individuals in response to several classes of chemotherapeutics. Upon treatment of these neuronal cells with the neurotoxic drug paclitaxel, vincristine or cisplatin, we identified significant differences in five morphological phenotypes among drugs, including total outgrowth, mean/median/maximum process length, and mean outgrowth intensity (P < 0.05. The differences in damage among drugs reflect differences in their mechanisms of action and clinical CIPN manifestations. We show the potential of the model for gene perturbation studies by demonstrating decreased expression of TUBB2A results in significantly increased sensitivity of neurons to paclitaxel (0.23 ± 0.06 decrease in total neurite outgrowth, P = 0.011. The variance in several neurite outgrowth and apoptotic phenotypes upon treatment with one of the neurotoxic drugs is significantly greater between than within neurons derived from four different individuals (P < 0.05, demonstrating the potential of iPSC-derived neurons as a genetically diverse model for CIPN. The human neuron model will allow both for mechanistic studies of specific genes and genetic variants discovered in clinical studies and for screening of new drugs to prevent or treat CIPN.

  2. MicroRNA-101 regulates T-cell acute lymphoblastic leukemia progression and chemotherapeutic sensitivity by targeting Notch1.

    Science.gov (United States)

    Qian, Lu; Zhang, Wanggang; Lei, Bo; He, Aili; Ye, Lianhong; Li, Xingzhou; Dong, Xin

    2016-11-01

    The present study aimed to investigate the role of microRNA (miR)-101 in acute lymphoblastic leukemia progression and chemoresistance. Furthermore, a novel target gene of miR-101 was identified. Here, we confirmed that miR-101 was significantly downregulated in the blood samples of patients with T-cell acute lymphoblastic leukemia (T-ALL) compared with the healthy controls, as determined by reverse transcription quantitative polymerase chain reaction (RTqPCR) analysis. The in vitro experiments demonstrated that miR-101 significantly repressed the proliferation and invasion, and induced potent apoptosis in Jurkat cells, as determined by CCK-8, flow cytometer and cell invasion assays. Luciferase assay confirmed that Notch1 was a target gene of miR-101, and western blotting showed that miR-101 suppressed the expression of Notch1 at the protein level. Moreover, functional restoration assays revealed that Notch1 mediates the effects of miR-101 on Jurkat cell proliferation, apoptosis and invasion. miR-101 enhanced the sensitivity of Jurkat cells to the chemotherapeutic agent adriamycin. Taken together, our results show for the first time that miR-101 acts as a tumor suppressor in T-cell acute lymphoblastic leukaemia and it could enhance chemotherapeutic sensitivity. Furthermore, Notch1 was identified to be a novel target of miR-101. This study indicates that miR-101 may represent a potential therapeutic target for T-cell acute lymphoblastic leukemia intervention.

  3. Promising change, delivering continuity

    DEFF Research Database (Denmark)

    Lund, Jens Friis; Sungusia, Eliezeri; Mabele, Mathew Bukhi

    2017-01-01

    REDD+ is an ambition to reduce carbon emissions from deforestation and forest degradation in the Global South. This ambition has generated unprecedented commitment of political support and financial funds for the forest-development sector. Many academics and people-centered advocacy organizations...... have conceptualized REDD+ as an example of ‘‘green grabbing” and have voiced fears of a potential global rush for land and trees. In this paper we argue that, in practice and up until now, REDD+ resembles longstanding dynamics of the development and conservation industry, where the promise of change...... becomes a discursive commodity that is constantly reproduced and used to generate value and appropriate financial resources. We thus argue for a re-conceptualization of REDD+ as a conservation fad within the broader political economy of development and conservation. We derive this argument from a study...

  4. Possible involvement of the Sigma-1 receptor chaperone in chemotherapeutic-induced neuropathic pain.

    Science.gov (United States)

    Tomohisa, Mori; Junpei, Ohya; Aki, Masumoto; Masato, Harumiya; Mika, Fukase; Kazumi, Yoshizawa; Teruo, Hayashi; Tsutomu, Suzuki

    2015-11-01

    Previous studies have shown that ligands of the sigma-1 receptor chaperone (Sig-1R) regulate pain-related behaviors. Clinical use of chemotherapeutics is often compromised due to their adverse side effects, particularly those related to neuropathy. Previous studies have shown that repeated administration of oxaliplatin and paclitaxel produces neuropathy in rodents. Therefore, the aim of the present study was to clarify the involvement of the Sig-1R in chemotherapeutic-induced neuropathy by examining the effects of oxaliplatin and paclitaxel on the Sig-1R levels in the spinal cord, and by examining the effects of Sig-1R agonist and antagonist on oxaliplatin- and paclitaxel-induced neuropathy in rats. Chemotherapeutic-induced neuropathic pain was accompanied by a significant reduction of the Sig-1R level in the spinal cord. Furthermore, the administration of paclitaxel to CHO cells that stably overexpressed Sig-1Rs induced the clustering of Sig-1Rs. We also found that the Sig-1R agonist SA4503 potently inhibited the neuropathy induced by oxaliplatin- and paclitaxel, whereas this action was abolished by the Sig-1R antagonist NE-100. These results suggest that the reduction of Sig-1R activity is involved in chemotherapeutic-induced neuropathy, and the Sig-1R agonist SA4503 could serve as a potential candidate for the treatment of chemotherapeutic-induced neuropathy. © 2015 Wiley Periodicals, Inc.

  5. Chemotherapeutic Drugs and Mitochondrial Dysfunction: Focus on Doxorubicin, Trastuzumab, and Sunitinib

    Directory of Open Access Journals (Sweden)

    Stefania Gorini

    2018-01-01

    Full Text Available Many cancer therapies produce toxic side effects whose molecular mechanisms await full elucidation. The most feared and studied side effect of chemotherapeutic drugs is cardiotoxicity. Also, skeletal muscle physiology impairment has been recorded after many chemotherapeutical treatments. However, only doxorubicin has been extensively studied for its side effects on skeletal muscle. Chemotherapeutic-induced adverse side effects are, in many cases, mediated by mitochondrial damage. In particular, trastuzumab and sunitinib toxicity is mainly associated with mitochondria impairment and is mostly reversible. Vice versa, doxorubicin-induced toxicity not only includes mitochondria damage but can also lead to a more robust and extensive cell injury which is often irreversible and lethal. Drugs interfering with mitochondrial functionality determine the depletion of ATP reservoirs and lead to subsequent reversible contractile dysfunction. Mitochondrial damage includes the impairment of the respiratory chain and the loss of mitochondrial membrane potential with subsequent disruption of cellular energetic. In a context of increased stress, AMPK has a key role in maintaining energy homeostasis, and inhibition of the AMPK pathway is one of the proposed mechanisms possibly mediating mitochondrial toxicity due to chemotherapeutics. Therapies targeting and protecting cell metabolism and energy management might be useful tools in protecting muscular tissues against the toxicity induced by chemotherapeutic drugs.

  6. In vitro testing of chemotherapeutic drug combinations in acute myelocytic leukaemia using the fluorometric microculture cytotoxicity assay (FMCA).

    Science.gov (United States)

    Larsson, R; Fridborg, H; Kristensen, J; Sundström, C; Nygren, P

    1993-05-01

    The fluorometric microculture cytotoxicity assay (FMCA) was employed for analysing the effect of different chemotherapeutic drug combinations and their single constituents in 44 cases of acute myelocytic leukaemia (AML). A large heterogeneity with respect to cell kill was observed for all combinations tested, the interactions ranging from antagonistic to synergistic in terms of the multiplicative concept for drug interactions. However, an 'additive' model provided a significantly better fit of the data compared to the effect of the most active single agent of the combination (Dmax) for several common antileukaemic drug combinations. When the two interaction models were related to treatment outcome 38% of the non-responders showed preference for the additive model whereas the corresponding figure for responders was 80%. Overall, in 248 of 290 (85%) tests performed with drug combinations, there was an agreement between the effect of the combination and that of the most active single component. Direct comparison of Dmax and the combination for correlation with clinical outcome demonstrated only minor differences in the ability to predict drug resistance. The results show that FMCA appear to report drug interactions in samples from patients with AML in accordance with clinical experience. Furthermore, testing single agents as a substitute for drug combinations may be adequate for detection of clinical drug resistance to combination therapy in AML.

  7. Synthetic analogues of natural semiochemicals as promising insect control agents

    International Nuclear Information System (INIS)

    Ujvary, Istvan; Toth, Miklos; Guerin, Patrick

    2000-01-01

    After decades of research and development, insect pheromones and other semiochemicals became indispensable tools of ecologically based agricultural pest and disease vector management programmes with main uses as: 1) detection and population monitoring of emerging and migrating insects, 2) mass trapping of insects, 3) combined formulation of semiochemicals and insecticides ('lure-and-kill'), and 4) mating disruption with specially formulated pheromone components. In spite of their demonstrated safety and biodegradability, the direct application of these semiochemicals for pest control has not fulfilled initial expectations. Nonetheless considerable field experience has been accumulated (Carde and Minks 1995). Evidently, two important factors limit the practical potential of these substances: 1) inherent in their particular mode of action, semiochemicals, especially pheromones, are effectively cleared by specific enzymes in the insect antennae, and 2) some of these compounds contain labile functional moieties that are prone to degradation (oxidation, isomerisation and polymerisation) under field conditions. Appropriate chemical modifications of these natural compounds, however, can circumvent these problems by providing synthetic analogues (sometimes also called parapheromones or antipheromones; for early studies, see Roelofs and Comeau 1971, Payne et al. 1973) which in ideal cases are not only more potent and environmentally acceptable but more economical as well. It should also be mentioned that many effective attractants have been discovered through the empirical screening of synthetic chemicals, some of which have actually turned out to be structural relatives of natural semiochemicals of the particular insect. In this paper, selected case studies of analogues of sex pheromones and kairomones will be presented. The examples from our work include nitrile bioisosteres of labile aldehyde pheromone components of the cranberry girdler moth, Chrysoteuchia topiaria Zeller; analogues of (Z)-11-hexadecenyl acetate, a principal component of several important lepidopteran species and analogues of 1-octen-3-ol and 3-n-propylphenol, two kairomonal cattle odour components attractive to tsetse flies (Glossina spp.)

  8. Cannabinoids: New Promising Agents in the Treatment of Neurological Diseases

    OpenAIRE

    Sabrina Giacoppo; Giuseppe Mandolino; Maria Galuppo; Placido Bramanti; Emanuela Mazzon

    2014-01-01

    Nowadays, Cannabis sativa is considered the most extensively used narcotic. Nevertheless, this fame obscures its traditional employ in native medicine of South Africa, South America, Turkey, Egypt and in many regions of Asia as a therapeutic drug. In fact, the use of compounds containing Cannabis and their introduction in clinical practice is still controversial and strongly limited by unavoidable psychotropic effects. So, overcoming these adverse effects represents the main open question on ...

  9. Cannabinoids: New Promising Agents in the Treatment of Neurological Diseases

    Directory of Open Access Journals (Sweden)

    Sabrina Giacoppo

    2014-11-01

    Full Text Available Nowadays, Cannabis sativa is considered the most extensively used narcotic. Nevertheless, this fame obscures its traditional employ in native medicine of South Africa, South America, Turkey, Egypt and in many regions of Asia as a therapeutic drug. In fact, the use of compounds containing Cannabis and their introduction in clinical practice is still controversial and strongly limited by unavoidable psychotropic effects. So, overcoming these adverse effects represents the main open question on the utilization of cannabinoids as new drugs for treatment of several pathologies. To date, therapeutic use of cannabinoid extracts is prescribed in patients with glaucoma, in the control of chemotherapy-related vomiting and nausea, for appetite stimulation in patients with anorexia-cachexia syndrome by HIV, and for the treatment of multiple sclerosis symptoms. Recently, researcher efforts are aimed to employ the therapeutic potentials of Cannabis sativa in the modulation of cannabinoid receptor activity within the central nervous system, particularly for the treatment of neurodegenerative diseases, as well as psychiatric and non-psychiatric disorders. This review evaluates the most recent available data on cannabinoids utilization in experimental and clinical studies, and highlights their beneficial effects in the prevention of the main neurological diseases and for the clinical treatment of symptoms with them correlated.

  10. Chemotherapeutic Drugs: DNA Damage and Repair in Glioblastoma.

    Science.gov (United States)

    Annovazzi, Laura; Mellai, Marta; Schiffer, Davide

    2017-05-26

    Despite improvements in therapeutic strategies, glioblastoma (GB) remains one of the most lethal cancers. The presence of the blood-brain barrier, the infiltrative nature of the tumor and several resistance mechanisms account for the failure of current treatments. Distinct DNA repair pathways can neutralize the cytotoxicity of chemo- and radio-therapeutic agents, driving resistance and tumor relapse. It seems that a subpopulation of stem-like cells, indicated as glioma stem cells (GSCs), is responsible for tumor initiation, maintenance and recurrence and they appear to be more resistant owing to their enhanced DNA repair capacity. Recently, attention has been focused on the pivotal role of the DNA damage response (DDR) in tumorigenesis and in the modulation of therapeutic treatment effects. In this review, we try to summarize the knowledge concerning the main molecular mechanisms involved in the removal of genotoxic lesions caused by alkylating agents, emphasizing the role of GSCs. Beside their increased DNA repair capacity in comparison with non-stem tumor cells, GSCs show a constitutive checkpoint expression that enables them to survive to treatments in a quiescent, non-proliferative state. The targeted inhibition of checkpoint/repair factors of DDR can contribute to eradicate the GSC population and can have a great potential therapeutic impact aiming at sensitizing malignant gliomas to treatments, improving the overall survival of patients.

  11. Promising pesticide results

    International Nuclear Information System (INIS)

    Wallace, Paula

    2012-01-01

    wastewater. For example, DDT has been linked to diabetes and liver, pancreatic and breast cancer, and is a 'probable' carcinogen, according to the US Environmental Protection Agency.” DDT has a half-life of up to 30 years in soil, which means only half its toxicity is naturally depleted through chemical breakdown over a 30-year period. Arsenic, however, which was used in DDT pesticides, does not breakdown at all over time. Moreover, epidemiological studies suggest that DDT and DDE cause serious illness. “Perhaps more worrying is the finding that DDT and its breakdown products are transported from warmer to colder climates around the world by a process called global distillation, thereby concentrating in colder climates and accumulating in the food web, leading to long-term ecological damage,” said Barros. By reducing DDT in the environment, these findings have the potential to aid in the sustainable global management of legacy pesticide contamination. For example, Virotec notes there are some 347 former cattle dip sites inthe region of Kyogle Shire Council in northern NSW, 259 in Lismore Shire Council and a further 211 in Richmond Valley Shire Council. The number of sheep dip sites throughout NSW and Queensland, which are also contaminated with arsenic and DDT, are of a comparable scale. Barros went on to point out that while the treatment of arsenic in soil is relatively straightforward, irrespective of whether treated in situ or ex situ, the treatment of DDT in soil is highly problematic. “Most soil treatments designed to destroy organic compounds in soil involve the introduction of key bacterial agents, because lower sources of energy simply do not have the requisite power to breakdown the long-chain organic molecules. However, as DDT is a pesticide it tends to kill both indigenous and introduced bacteria before they can break down the DDT molecule, thereby eliminating the source of potential remediation,” said Barros. Another challenge relates to the stability

  12. Promising new developments in cancer chemotherapy.

    Science.gov (United States)

    Ferrante, K; Winograd, B; Canetta, R

    1999-01-01

    The positive impact on survival of traditional chemotherapeutic agents has renewed interest in developing newer cytotoxic agents and orally active compounds with improved therapeutic indices. In addition, new insights into the pathways of human tumorigenesis have led to novel approaches aimed at specific mechanism-based targets. The taxane class, of which paclitaxel was the first member, has the unique ability to promote and stabilize microtubule function directly, thereby inhibiting mitotic progression and inducing apoptotic cell death. Paclitaxel provides treatment benefit in a broad range of solid tumors including breast, ovarian, and lung cancer. The success with paclitaxel stimulated interest in the microtubule as a new therapeutic target. Taxane analogues with improved preclinical efficacy have been identified and are entering clinical trials. The enthusiasm for oral anticancer agents and the therapeutic importance of platinum compounds has led to the development of JM216 (satraplatin), a novel platinum IV coordination complex with oral activity in cisplatin-resistant cell lines, which is now in phase III trials in prostate cancer. Another compound in late development is DPPE, a chemopotentiator that enhances the in vivo antitumor effects of cytotoxic agents such as doxorubicin, cyclophosphamide, and cisplatin. Agents that inhibit topoisomerase I and II have also been of interest. TAS-103 is a dual topoisomerase I and II inhibitor with preclinical efficacy in a broad spectrum of tumors and in multidrug-resistant tumor cell lines. Vaccination strategies represent a rational therapeutic approach in the minimal residual disease or high-risk adjuvant therapy setting. The GMK and MGV vaccines utilizing ganglioside antigens overexpressed on human tumors such as melanoma and small cell lung cancer appear to induce antibody production reliably at tolerable doses and are under further clinical investigation. Inhibition of matrix metalloproteinases (MMPs) is another

  13. Overcoming Multidrug Resistance via Photodestruction of ABCG2-Rich Extracellular Vesicles Sequestering Photosensitive Chemotherapeutics

    Science.gov (United States)

    Goler-Baron, Vicky; Assaraf, Yehuda G.

    2012-01-01

    Multidrug resistance (MDR) remains a dominant impediment to curative cancer chemotherapy. Efflux transporters of the ATP-binding cassette (ABC) superfamily including ABCG2, ABCB1 and ABCC1 mediate MDR to multiple structurally and functionally distinct antitumor agents. Recently we identified a novel mechanism of MDR in which ABCG2-rich extracellular vesicles (EVs) form in between attached neighbor breast cancer cells and highly concentrate various chemotherapeutics in an ABCG2-dependent manner, thereby sequestering them away from their intracellular targets. Hence, development of novel strategies to overcome MDR modalities is a major goal of cancer research. Towards this end, we here developed a novel approach to selectively target and kill MDR cancer cells. We show that illumination of EVs that accumulated photosensitive cytotoxic drugs including imidazoacridinones (IAs) and topotecan resulted in intravesicular formation of reactive oxygen species (ROS) and severe damage to the EVs membrane that is shared by EVs-forming cells, thereby leading to tumor cell lysis and the overcoming of MDR. Furthermore, consistent with the weak base nature of IAs, MDR cells that are devoid of EVs but contained an increased number of lysosomes, highly accumulated IAs in lysosomes and upon photosensitization were efficiently killed via ROS-dependent lysosomal rupture. Combining targeted lysis of IAs-loaded EVs and lysosomes elicited a synergistic cytotoxic effect resulting in MDR reversal. In contrast, topotecan, a bona fide transport substrate of ABCG2, accumulated exclusively in EVs of MDR cells but was neither detected in lysosomes of normal breast epithelial cells nor in non-MDR breast cancer cells. This exclusive accumulation in EVs enhanced the selectivity of the cytotoxic effect exerted by photodynamic therapy to MDR cells without harming normal cells. Moreover, lysosomal alkalinization with bafilomycin A1 abrogated lysosomal accumulation of IAs, consequently preventing

  14. Agent-Based Optimization

    CERN Document Server

    Jędrzejowicz, Piotr; Kacprzyk, Janusz

    2013-01-01

    This volume presents a collection of original research works by leading specialists focusing on novel and promising approaches in which the multi-agent system paradigm is used to support, enhance or replace traditional approaches to solving difficult optimization problems. The editors have invited several well-known specialists to present their solutions, tools, and models falling under the common denominator of the agent-based optimization. The book consists of eight chapters covering examples of application of the multi-agent paradigm and respective customized tools to solve  difficult optimization problems arising in different areas such as machine learning, scheduling, transportation and, more generally, distributed and cooperative problem solving.

  15. Biological Agents

    Science.gov (United States)

    ... E-Tools Safety and Health Topics / Biological Agents Biological Agents This page requires that javascript be enabled ... 202) 693-2300 if additional assistance is required. Biological Agents Menu Overview In Focus: Ebola Frederick A. ...

  16. Efficacy Comparison of Six Chemotherapeutic Combinations for Osteosarcoma and Ewing's Sarcoma Treatment: A Network Meta-Analysis.

    Science.gov (United States)

    Zhang, Tao; Zhang, Song; Yang, Feifei; Wang, Lili; Zhu, Sigang; Qiu, Bing; Li, Shunhua; Deng, Zhongliang

    2018-01-01

    This study aimed to address the insufficiency of traditional meta-analysis and provide improved guidelines for the clinical practice of osteosarcoma treatment. The heterogeneity of the fixed-effect model was calculated, and when necessary, a random-effect model was adopted. Furthermore, the direct and indirect evidence was pooled together and exhibited in the forest plot and slash table. The surface under the cumulative ranking curve (SUCRA) value was also measured to rank each intervention. Finally, heat plot was introduced to demonstrate the contribution of each intervention and the inconsistency between direct and indirect comparisons. This network meta-analysis included 32 trials, involving a total of 5,626 subjects reported by 28 articles. All the treatments were classified into six chemotherapeutic combinations: dual agent with or without ifosfamide (IFO), multi-agent with or without IFO, and dual agent or multi-agent with IFO and etoposide. For the primary outcomes, both overall survival (OS) and event-free survival (EFS) rates were considered. The multi-agent integrated with IFO and etoposide showed an optimal performance for 5-year OS, 10-year OS, 3-year EFS, 5-year EFS, and 10-year EFS when compared with placebo. The SUCRA value of this treatment was also the highest of these six interventions. However, multi-drug with IFO alone had the highest SUCRA value of 0.652 and 0.516 when it came to relapse and lung-metastasis. It was efficient to some extent, but no significant difference was observed in both outcomes. Chemotherapy, applied as induction or adjuvant treatment with radiation therapy or surgery, is able to increase the survival rate of patients, especially by combining multi-drug with IFO and etoposide, which demonstrated the best performance in both OS and EFS. As for relapse and the lung-metastasis, multiple agents with IFO alone seemed to have the optimal efficiency, although no significant difference was observed here. J. Cell. Biochem. 119: 250

  17. Maximum standard uptake value on pre-chemotherapeutic FDG-PET is a significant parameter for disease progression of newly diagnosed lymphoma

    International Nuclear Information System (INIS)

    Eo, Jae Seon; Lee, Won Woo; Chung, June Key; Lee, Myung Chul; Kim, Sang Eun

    2005-01-01

    F-18 FDG-PET is useful for detection and staging of lymphoma. We investigated the prognostic significance of maximum standard uptake (maxSUV) value of FDG-PET for newly diagnosed lymphoma patients before chemotherapy. Twenty-seven patients (male: female = 17: 10: age: 49±19 years) with newly diagnosed lymphoma were enrolled. Nine-teen patients suffered from B cell lymphoma, 6 Hodgkins disease and 2 T cell lymphoma. One patient was stage I, 9 stage II, 3 stage III, 1 stage IV and 13 others. All patients underwent FDG-PET before initiation of chemotherapy. MaxSUV values using lean body weight were obtained for main and largest lesion to represent maxSUV of the patients. The disease progression was defined as total change of the chemotherapeutic regimen or addition of new chemotherapeutic agent during follow up period. The observed period was 389±224 days. The value of maxSUV ranged from 3 to 18 (mean±SD = 10.6±4.4). The disease progressions occurred in 6 patients. Using Cox proportional-hazard regression analysis, maxSUV was identified as a significant parameter for the disease progression free survival (p=0.044). Kaplan-Meier survival curve analysis revealed that the group with higher maxSUV (=10.6, n=5) suffered from shorter disease progression free survival (median 299 days) than the group with lower maxSUV (<10.6, n = 22) (median 378 days, p=0.0146). We found that maxSUV on pre-chemotherapeutic F-18 FDG-PET for newly diagnosed lymphoma patients is a significant parameter for disease progression. Lymphoma patients can be stratified before initiation of chemotherapy in terms of disease progression by the value of maxSUV 10.6

  18. A Potential Adjuvant Agent of Chemotherapy: Sepia Ink Polysaccharides

    Directory of Open Access Journals (Sweden)

    Fangping Li

    2018-03-01

    Full Text Available Sepia ink polysaccharide (SIP isolated from squid and cuttlefish ink is a kind of acid mucopolysaccharide that has been identified in three types of primary structures from squid (Illex argentinus and Ommastrephes bartrami, cuttlefish Sepiella maindroni, and cuttlefish Sepia esculenta ink. Although SIP has been proved to be multifaceted, most of the reported evidence has illuminated its chemopreventive and antineoplastic activities. As a natural product playing a role in cancer treatment, SIP may be used as chemotherapeutic ancillary agent or functional food. Based on the current findings on SIP, we have summarized four topics in this review, including: chemopreventive, antineoplastic, chemosensitive, and procoagulant and anticoagulant activities, which are correlative closely with the actions of anticancer agents on cancer patients, such as anticancer, toxicity and thrombogenesis, with the latter two actions being common causes of death in cancer cases exposed to chemotherapeutic agents.

  19. Chemotherapeutic treatment efficacy and sensitivity are increased by adjuvant alternating electric fields (TTFields)

    International Nuclear Information System (INIS)

    Kirson, Eilon D; Goldsher, Dorit; Wasserman, Yoram; Palti, Yoram; Schneiderman, Rosa S; Dbalý, Vladimír; Tovaryš, František; Vymazal, Josef; Itzhaki, Aviran; Mordechovich, Daniel; Gurvich, Zoya; Shmueli, Esther

    2009-01-01

    The present study explores the efficacy and toxicity of combining a new, non-toxic, cancer treatment modality, termed Tumor Treating Fields (TTFields), with chemotherapeutic treatment in-vitro, in-vivo and in a pilot clinical trial. Cell proliferation in culture was studied in human breast carcinoma (MDA-MB-231) and human glioma (U-118) cell lines, exposed to TTFields, paclitaxel, doxorubicin, cyclophosphamide and dacarbazine (DTIC) separately and in combinations. In addition, we studied the effects of combining chemotherapy with TTFields in an animal tumor model and in a pilot clinical trial in recurrent and newly diagnosed GBM patients. The efficacy of TTFields-chemotherapy combination in-vitro was found to be additive with a tendency towards synergism for all drugs and cell lines tested (combination index ≤ 1). The sensitivity to chemotherapeutic treatment was increased by 1–3 orders of magnitude by adjuvant TTFields therapy (dose reduction indexes 23 – 1316). Similar findings were seen in an animal tumor model. Finally, 20 GBM patients were treated with TTFields for a median duration of 1 year. No TTFields related systemic toxicity was observed in any of these patients, nor was an increase in Temozolomide toxicity seen in patients receiving combined treatment. In newly diagnosed GBM patients, combining TTFields with Temozolomide treatment led to a progression free survival of 155 weeks and overall survival of 39+ months. These results indicate that combining chemotherapeutic cancer treatment with TTFields may increase chemotherapeutic efficacy and sensitivity without increasing treatment related toxicity

  20. The Promises of Biology and the Biology of Promises

    DEFF Research Database (Denmark)

    Lee, Jieun

    2015-01-01

    commitments with differently imagined futures. I argue that promises are constitutive of the stem cell biology, rather than being derivative of it. Since the biological concept of stem cells is predicated on the future that they promise, the biological life of stem cells is inextricably intertwined...... patients’ bodies in anticipation of materializing the promises of stem cell biology, they are produced as a new form of biovaluable. The promises of biology move beyond the closed circuit of scientific knowledge production, and proliferate in the speculative marketplaces of promises. Part II looks at how...... of technologized biology and biological time can appear promising with the backdrop of the imagined intransigence of social, political, and economic order in the Korean society....

  1. New in vitro system to predict chemotherapeutic efficacy of drug combinations in fresh tumor samples

    Directory of Open Access Journals (Sweden)

    Frank Christian Kischkel

    2017-03-01

    Full Text Available Background To find the best individual chemotherapy for cancer patients, the efficacy of different chemotherapeutic drugs can be predicted by pretesting tumor samples in vitro via the chemotherapy-resistance (CTR-Test®. Although drug combinations are widely used among cancer therapy, so far only single drugs are tested by this and other tests. However, several first line chemotherapies are combining two or more chemotherapeutics, leading to the necessity of drug combination testing methods. Methods We established a system to measure and predict the efficacy of chemotherapeutic drug combinations with the help of the Loewe additivity concept in combination with the CTR-test. A combination is measured by using half of the monotherapy’s concentration of both drugs simultaneously. With this method, the efficacy of a combination can also be calculated based on single drug measurements. Results The established system was tested on a data set of ovarian carcinoma samples using the combination carboplatin and paclitaxel and confirmed by using other tumor species and chemotherapeutics. Comparing the measured and the calculated values of the combination testings revealed a high correlation. Additionally, in 70% of the cases the measured and the calculated values lead to the same chemotherapeutic resistance category of the tumor. Conclusion Our data suggest that the best drug combination consists of the most efficient single drugs and the worst drug combination of the least efficient single drugs. Our results showed that single measurements are sufficient to predict combinations in specific cases but there are exceptions in which it is necessary to measure combinations, which is possible with the presented system.

  2. A molecular targeting against nuclear factor-κB, as a chemotherapeutic approach for human malignant mesothelioma

    International Nuclear Information System (INIS)

    Nishikawa, Sho; Tanaka, Akane; Matsuda, Akira; Oida, Kumiko; Jang, Hyosun; Jung, Kyungsook; Amagai, Yosuke; Ahn, Ginae; Okamoto, Noriko; Ishizaka, Saori; Matsuda, Hiroshi

    2014-01-01

    Chronic inflammation due to the absorption of asbestos is an important cause of mesothelioma. Although the increased prevalence of mesothelioma is a serious problem, the development of effective chemotherapeutic agents remains incomplete. As the nuclear factor-κB (NF-κB) pathway contributes to malignant transformation of various types of cells, we explored NF-κB activity in three different pathological types of malignant mesothelioma cells, and evaluated the therapeutic potential of a recently reported NF-κB inhibitor, IMD-0354. NF-κB was constantly activated in MSTO-211H, NCI-H28, and NCI-H2052 cells, and the proliferation of these cell lines was inhibited by IMD-0354. D-type cyclins were effectively suppressed in mixed tissue type MSTO-211H, leading to cell cycle arrest at sub G 1 /G 1 phase. IMD-0354 reduced cyclin D3 in both epithelial tissue type NCI-H28 and sarcomatoid tissue type NCI-H2052. In a sphere formation assay, IMD-0354 effectively decreased the number and diameter of MSTO-211H spheres. Preincubation of MSTO-211H cells with IMD-0354 delayed tumor formation in transplanted immunodeficient mice. Furthermore, administration of IMD-0354 markedly rescued the survival rate of mice that received intrathoracic injections of MSTO-211H cells. These results indicate that a targeted drug against NF-κB might have therapeutic efficacy in the treatment of human malignant mesothelioma

  3. Interstitial shadow on chest CT is associated with the onset of interstitial lung disease caused by chemotherapeutic drugs

    International Nuclear Information System (INIS)

    Niho, Seiji; Goto, Koichi; Yoh, Kiyotaka; Kim, Y.H.; Ohmatsu, Hironobu; Kubota, Kaoru; Saijo, Nagahiro; Nishiwaki, Yutaka

    2006-01-01

    Pretreatment computerized tomography (CT) films of the chest was studied to clarify the influence of interstitial shadow on developing interstitial lung disease (ILD). Eligible patients were those lung cancer patients who started to receive first-line chemotherapy between October 2001 and March 2004. Patients who received thoracic radiotherapy to the primary lesion, mediastinum, spinal or rib metastases were excluded. We reviewed pretreatment conventional CT and plain X-ray films of the chest. Ground-glass opacity, consolidation or reticular shadow without segmental distribution was defined as interstitial shadow, with this event being graded as mild, moderate or severe. If interstitial shadow was detected on CT films of the chest, but not via plain chest X-ray, it was graded as mild. Patients developing ILD were identified from medial records. A total of 502 patients were eligible. Mild, moderate and severe interstitial shadow was identified in 7, 8 and 5% of patients, respectively. A total of 188 patients (37%) received tyrosine kinase inhibitor (TKI) treatment, namely gefitinib or erlotinib. Twenty-six patients (5.2%) developed ILD either during or after chemotherapy. Multivariate analyses revealed that interstitial shadow on CT films of the chest and treatment history with TKI were associated with the onset of ILD. It is recommended that patients with interstitial shadow on chest CT are excluded from future clinical trials until this issue is further clarified, as it is anticipated that use of chemotherapeutic agents frequently mediate onset of ILD in this context. (author)

  4. Application of Mesenchymal Stem Cells for Therapeutic Agent Delivery in Anti-tumor Treatment

    Directory of Open Access Journals (Sweden)

    Daria S. Chulpanova

    2018-03-01

    Full Text Available Mesenchymal stem cells (MSCs are non-hematopoietic progenitor cells, which can be isolated from different types of tissues including bone marrow, adipose tissue, tooth pulp, and placenta/umbilical cord blood. There isolation from adult tissues circumvents the ethical concerns of working with embryonic or fetal stem cells, whilst still providing cells capable of differentiating into various cell lineages, such as adipocytes, osteocytes and chondrocytes. An important feature of MSCs is the low immunogenicity due to the lack of co-stimulatory molecules expression, meaning there is no need for immunosuppression during allogenic transplantation. The tropism of MSCs to damaged tissues and tumor sites makes them a promising vector for therapeutic agent delivery to tumors and metastatic niches. MSCs can be genetically modified by virus vectors to encode tumor suppressor genes, immunomodulating cytokines and their combinations, other therapeutic approaches include MSCs priming/loading with chemotherapeutic drugs or nanoparticles. MSCs derived membrane microvesicles (MVs, which play an important role in intercellular communication, are also considered as a new therapeutic agent and drug delivery vector. Recruited by the tumor, MSCs can exhibit both pro- and anti-oncogenic properties. In this regard, for the development of new methods for cancer therapy using MSCs, a deeper understanding of the molecular and cellular interactions between MSCs and the tumor microenvironment is necessary. In this review, we discuss MSC and tumor interaction mechanisms and review the new therapeutic strategies using MSCs and MSCs derived MVs for cancer treatment.

  5. Correlation between radioactivity and chemotherapeutics of the 111In-VNB-liposome in pharmacokinetics and biodistribution in rats

    Directory of Open Access Journals (Sweden)

    Tsai TH

    2012-02-01

    Full Text Available Wen-Chuan Lee1,*, Chih-Hsien Chang2,3,*, Chih-Min Huang1, Yu-Tse Wu1, Liang-Cheng Chen2, Chung-Li Ho2, Tsui-Jung Chang2, Te-Wei Lee2, Tung-Hu Tsai1,41Institute of Traditional Medicine, School of Medicine, National Yang-Ming University, Taipei, 2Division of Isotope Application, Institute of Nuclear Energy Research, Taoyuan, 3Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, 4Department of Education and Research, Taipei City Hospital, Taipei, Taiwan*These authors contributed equally to this workBackground: The combination of a radioisotope with a chemotherapeutic agent in a liposomal carrier (ie, Indium-111-labeled polyethylene glycol pegylated liposomal vinorelbine, [111In-VNB-liposome] has been reported to show better therapeutic efficiency in tumor growth suppression. Nevertheless, the challenge remains as to whether this therapeutic effect is attributable to the combination of a radioisotope with chemotherapeutics. The goal of this study was to investigate the pharmacokinetics, biodistribution, and correlation of Indium-111 radioactivity and vinorelbine concentration in the 111In-VNB-liposome.Methods: The VNB-liposome and 111In-VNB-liposome were administered to rats. Blood, liver, and spleen tissue were collected to determine the distribution profile of the 111In-VNB-liposome. A liquid chromatography tandem mass spectrometry system and gamma counter were used to analyze the concentration of vinorelbine and radioactivity of Indium-111.Results: High uptake of the 111In-VNB-liposome in the liver and spleen demonstrated the properties of a nanosized drug delivery system. Linear regression showed a good correlation (r = 0.97 between Indium-111 radioactivity and vinorelbine concentration in the plasma of rats administered the 111In-VNB-liposome.Conclusion: A significant positive correlation between the pharmacokinetics and biodistribution of 111Indium radioactivity and vinorelbine in blood, spleen

  6. A review of mechanisms of circumvention and modulation of chemotherapeutic drug resistance.

    Science.gov (United States)

    O'Connor, R

    2009-05-01

    Drug resistance is a serious limitation to the effective treatment of a number of common malignancies. Thirty years of laboratory and clinical research have greatly defined the molecular alterations underlying many drug resistance processes in cancer. Based on this knowledge, strategies to overcome the impact of resistance and increase the efficacy of cancer treatment have been translated from laboratory models to clinical trials. This article reviews laboratory and, in particular, clinical attempts at drug resistance circumvention from early forays in the inhibition of cellular efflux pump-mediated drug resistance through to more selective circumvention agent strategies and into inhibition of the other important mechanisms which can allow cancer cells to survive therapy, such as apoptosis resistance. Despite some promising results to date, resistance inhibition strategies have largely failed due to poor understanding of the pharmacology, dynamics and complexity of the resistance phenotype. With the realisation that new molecularly-targeted agents can also be rendered ineffectual by the actions of resistance mechanisms, a major focus is once again emerging on identifying new strategies/pharmaceuticals which can augment the activity of the arsenal of more conventional cytotoxics and newer targeted anti-cancer drugs. Future tactical directions where old and new resistance strategies may merge to overcome this challenge are discussed.

  7. Innovative agents in cancer prevention.

    Science.gov (United States)

    Manson, Margaret M; Farmer, Peter B; Gescher, Andreas; Steward, William P

    2005-01-01

    There are many facets to cancer prevention: a good diet, weight control and physical activity, a healthy environment, avoidance of carcinogens such as those in tobacco smoke, and screening of populations at risk to allow early detection. But there is also the possibility of using drugs or naturally occurring compounds to prevent initiation of, or to suppress, tumour growth. Only a few such agents have been used to date in the clinic with any success, and these include non-steroidal anti-inflammatory drugs for colon, finasteride for prostate and tamoxifen or raloxifene for breast tumours. An ideal chemopreventive agent would restore normal growth control to a preneoplastic or cancerous cell population by modifying aberrant signalling pathways or inducing apoptosis (or both) in cells beyond repair. Characteristics for such an agent include selectivity for damaged or transformed cells, good bioavailability and more than one mechanism of action to foil redundancy or crosstalk in signalling pathways. As more research effort is being targeted towards this area, the distinction between chemotherapeutic and chemopreventive agents is blurring. Chemotherapeutic drugs are now being designed to target over- or under-active signalling molecules within cancer cells, a philosophy which is just as relevant in chemoprevention. Development of dietary agents is particularly attractive because of our long-standing exposure to them, their relative lack of toxicity, and encouraging indications from epidemiology. The carcinogenic process relies on the cell's ability to proliferate abnormally, evade apoptosis, induce angiogenesis and metastasise to distant sites. In vitro studies with a number of different diet-derived compounds suggest that there are molecules capable of modulating each of these aspects of tumour growth. However, on the negative side many of them have rather poor bioavailability. The challenge is to uncover their multiple mechanisms of action in order to predict their

  8. Histopathologic and Radiologic Assessment of Chemotherapeutic Response in Ewing's Sarcoma: A Review.

    Science.gov (United States)

    García-Castellano, José M; Atallah Yordi, Nagib; Reyes, Carolina; Healey, John H

    2012-01-01

    Ewing's sarcoma is a highly malignant tumor that metastasizes rapidly and is thus associated with a low survival rate. The intensification of chemotherapy has been shown to improve the overall survival of patients with Ewing's sarcoma. However, intensified chemotherapy can lead to increased toxicity or even the development of secondary malignancies. The stratification of patients with Ewing's sarcoma into "good" and "poor" responders may help guide the administration of progressively more intensified chemotherapy. Thus, an accurate assessment of the chemotherapeutic response, as well as the extent of chemotherapy-induced tumor necrosis, is critical for avoiding potential treatment-related complications in these patients. This paper reviews the methods currently used to evaluate chemotherapeutic response in Ewing's sarcoma, focusing specifically on histopathologic and imaging analyses, and discusses novel therapies and imaging methods that may help improve the overall survival of these patients.

  9. Histopathologic and Radiologic Assessment of Chemotherapeutic Response in Ewing's Sarcoma: A Review

    Directory of Open Access Journals (Sweden)

    José M. García-Castellano

    2012-01-01

    Full Text Available Ewing’s sarcoma is a highly malignant tumor that metastasizes rapidly and is thus associated with a low survival rate. The intensification of chemotherapy has been shown to improve the overall survival of patients with Ewing’s sarcoma. However, intensified chemotherapy can lead to increased toxicity or even the development of secondary malignancies. The stratification of patients with Ewing’s sarcoma into “good” and “poor” responders may help guide the administration of progressively more intensified chemotherapy. Thus, an accurate assessment of the chemotherapeutic response, as well as the extent of chemotherapy-induced tumor necrosis, is critical for avoiding potential treatment-related complications in these patients. This paper reviews the methods currently used to evaluate chemotherapeutic response in Ewing’s sarcoma, focusing specifically on histopathologic and imaging analyses, and discusses novel therapies and imaging methods that may help improve the overall survival of these patients.

  10. Breast cancer chemopreventive and chemotherapeutic effects of Camellia Sinensis (green tea): an updated review.

    Science.gov (United States)

    Rafieian-Kopaei, Mahmoud; Movahedi, Mino

    2017-02-01

    Camellia sinensis belongs to the plant family of Theaceae, native to East Asia, the Indian Subcontinent and Southeast Asia, but naturalized in many parts of the world. The aim of this study was to overview its anti-breast cancer chemopreventive and chemotherapeutic effects. This review article is aimed to overview breast cancer chemopreventive and chemotherapeutic effects of Camellia sinensis (green tea). This review article was carried out by searching studies in PubMed, Medline, Web of Science, and IranMedex databases. The initial search strategy identified around 108 references. In this study, 68 studies were accepted for further screening, and met all our inclusion criteria [in English, full text, chemopreventive and chemotherapeutic effects of Camellia sinensis and dated mainly from the year 1999 to 2016. The search terms were Camellia sinensis, chemopreventive, chemotherapeutic properties, pharmacological effects. The result of this study suggested that the catechin available in Camellia sinensis has properties which can prevent and treat breast cancer. It has also been shown to inhibit proliferation of breast cancer cells and to block carcinogenesis. It was found that increased Camellia sinensis consumption may lower the risk of breast cancer. Camellia sinensis intake was shown to reduce the risk of breast cancer incidence. In addition, potential breast cancer chemopreventive effect of Camellia sinensis both in vivo and in vitro was highly confirmed. However, the evidence of low effect and no effect was observed. More clinical trial studies are needed to prove its anti-breast cancer activity decisively. Camellia sinensis is broadly utilized as a part of customary medication since antiquated time because of its cost adequacy, and fewer reaction properties. The studies demonstrated anti-breast cancer activity of Camellia sinensis and its component by adjusting cell signaling pathways such as angiogenesis, apoptosis, and transcription factor. Furthermore

  11. Dipeptidyl peptidase IV as a potential target for selective prodrug activation and chemotherapeutic action in cancers.

    Science.gov (United States)

    Dahan, Arik; Wolk, Omri; Yang, Peihua; Mittal, Sachin; Wu, Zhiqian; Landowski, Christopher P; Amidon, Gordon L

    2014-12-01

    The efficacy of chemotherapeutic drugs is often offset by severe side effects attributable to poor selectivity and toxicity to normal cells. Recently, the enzyme dipeptidyl peptidase IV (DPPIV) was considered as a potential target for the delivery of chemotherapeutic drugs. The purpose of this study was to investigate the feasibility of targeting chemotherapeutic drugs to DPPIV as a strategy to enhance their specificity. The expression profile of DPPIV was obtained for seven cancer cell lines using DNA microarray data from the DTP database, and was validated by RT-PCR. A prodrug was then synthesized by linking the cytotoxic drug melphalan to a proline-glycine dipeptide moiety, followed by hydrolysis studies in the seven cell lines with a standard substrate, as well as the glycyl-prolyl-melphalan (GP-Mel). Lastly, cell proliferation studies were carried out to demonstrate enzyme-dependent activation of the candidate prodrug. The relative RT-PCR expression levels of DPPIV in the cancer cell lines exhibited linear correlation with U95Av2 Affymetrix data (r(2) = 0.94), and with specific activity of a standard substrate, glycine-proline-p-nitroanilide (r(2) = 0.96). The significantly higher antiproliferative activity of GP-Mel in Caco-2 cells (GI₅₀ = 261 μM) compared to that in SK-MEL-5 cells (GI₅₀ = 807 μM) was consistent with the 9-fold higher specific activity of the prodrug in Caco-2 cells (5.14 pmol/min/μg protein) compared to SK-MEL-5 cells (0.68 pmol/min/μg protein) and with DPPIV expression levels in these cells. Our results demonstrate the great potential to exploit DPPIV as a prodrug activating enzyme for efficient chemotherapeutic drug targeting.

  12. Early stage detection of chemotherapeutic effect on 203 GL glioma in mice as studied by P-31 NMR and flow cytometry

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Masamitsu; Yoshikawa, Koki; Nishikawa, Junichi; Iio, Masahiro; Shibui, Soichiro; Nomura, Kazuhiro; Saito, Hazime; Kodama, Masahiko

    1988-08-01

    The effect of chemotherapy against glioma in mouse was evaluated by /sup 31/P NMR spectroscopy and flow cytometry. We found that administration of ACNU or tegafur at a dose less than LD/sub 50/ resulted in the partial suppression of the ratio of inorganic phosphate (Pi)/phosphocreatine (PCr) and phosphomonoester (PME)/creatine phosphate (PCr) after 24 or 48 hr, although these ratios are usually increased together with growth of tumors. Flow cytometric analysis of glioma in vivo showed an accumulation in cells containing tetraploid DNA by G/sub 2/M block 24 - 48 hr after treatment. However, the change occurred at a period slightly later than that of the Pi/PCr ratio. In contrast, histological change was noted at eight days after administration. Hence, it is concluded that in vivo /sup 31/P NMR spectroscopy can detect a change in metabolic pathways in tumors as early as 24 - 48 hr after the administration of chemotherapeutic agents.

  13. Recent advances in nanoformulations for co-delivery of curcumin and chemotherapeutic drugs

    Directory of Open Access Journals (Sweden)

    Maryam Hashemi

    2017-01-01

    Full Text Available The application of chemotherapy in cancer treatment has been limited due to cause side effects such as toxicity against normal cells and drug resistance. In recent years, numerous studies have been focused on using natural products with chemotherapeutic drugs to enhance therapeutic efficiency and reduce cytotoxicity. On the other hand, encapsulation of drugs into nanoparticles (NPs can improve solubility of hydrophobic drug; circulation time in blood and the residence at the pathological site by enhance permeation and retention (EPR effect. It has been shown that curcumin (CUR has  wide range of pharmacological activities against many diseases such as cancer. CUR has been demonstrated to be a potent chemosensitizer that can induce additive or synergistic effects with chemotherapeutic drugs against different cancer cell lines.  Recently, various types of nanocarriers have been investigated for CUR.  In this review, different co-formulations containing Cur and chemotherapeutic drugs used in cancer therapy are discussed with emphasis on their pharmaceutical properties.

  14. Prevalence and sunlight photolysis of controlled and chemotherapeutic drugs in aqueous environments

    International Nuclear Information System (INIS)

    Lin, Angela Yu-Chen; Lin, Yen-Ching; Lee, Wan-Ning

    2014-01-01

    This study addresses the occurrences and natural fates of chemotherapeutics and controlled drugs when found together in hospital effluents and surface waters. The results revealed the presence of 11 out of 16 drugs in hospital effluents, and the maximum detected concentrations were at the μg L −1 level in the hospital effluents and the ng L −1 level in surface waters. The highest concentrations corresponded to meperidine, morphine, 5-fluorouracil and cyclophosphamide. The sunlight photolysis of the target compounds was investigated, and the results indicated that morphine and codeine can be significantly attenuated, with half-lives of 0.27 and 2.5 h, respectively, in natural waters. Photolysis can lower the detected environmental concentrations, also lowering the estimated environmental risks of the target drugs to human health. Nevertheless, 5-fluorouracil and codeine were found to have a high risk quotient (RQ), demonstrating the high risks of directly releasing hospital wastewater into the environment. - Highlights: • High occurrence of chemotherapeutics and controlled substances in aqueous systems. • Photolysis lowers the detected concentrations of morphine and codeine. • 5-fluorouracil and codeine in hospital effluents have high risk quotients. - Chemotherapeutics and controlled drugs occur at significant levels in hospital effluents and surface waters. Natural sunlight photolysis reduces their environmental occurrence

  15. Political Reputations and Campaign Promises

    OpenAIRE

    Aragones, Enriqueta; Palfrey, Thomas R.; Postlewaite, Andrew

    2006-01-01

    We analyze conditions under which candidates' reputations may affect voters' beliefs over what policy will be implemented by the winning candidate of an election. We develop a model of repeated elections with complete information in which candidates are purely ideological. We analyze an equilibrium in which voters' strategies involve a credible threat to punish candidates who renege on their campaign promises and in which all campaign promises are believed by voters and honored by candidates....

  16. Ifosfamide: chemotherapy with new promise and new problems for the urologist.

    Science.gov (United States)

    Watson, R A

    1984-11-01

    Ifosfamide, a chemotherapeutic agent, offers new hope as well as new problems for the uro-oncologist. The "good news" is that this drug is achieving marked benefits in treating resistant testis tumors and may even hold hope for patients with renal cell carcinoma. The "bad news" is that a price must be paid in toxicity--predominantly a severe and restrictive hemorrhagic cystitis. A breakthrough is the finding that oral administration of acetylcysteine (Mucomyst) may, to a large extent, prevent this untoward side effect.

  17. Plant-Derived Agents for Counteracting Cisplatin-Induced Nephrotoxicity

    OpenAIRE

    Ojha, Shreesh; Venkataraman, Balaji; Kurdi, Amani; Mahgoub, Eglal; Sadek, Bassem; Rajesh, Mohanraj

    2016-01-01

    Cisplatin (CSP) is a chemotherapeutic agent commonly used to treat a variety of malignancies. The major setback with CSP treatment is that its clinical efficacy is compromised by its induction of organ toxicity, particular to the kidneys and ears. Despite the significant strides that have been made in understanding the mechanisms underlying CSP-induced renal toxicity, advances in developing renoprotective strategies are still lacking. In addition, the renoprotective approaches described in th...

  18. Polyether ionophores-promising bioactive molecules for cancer therapy.

    Science.gov (United States)

    Huczyński, Adam

    2012-12-01

    The natural polyether ionophore antibiotics might be important chemotherapeutic agents for the treatment of cancer. In this article, the pharmacology and anticancer activity of the polyether ionophores undergoing pre-clinical evaluation are reviewed. Most of polyether ionophores have shown potent activity against the proliferation of various cancer cells, including those that display multidrug resistance (MDR) and cancer stem cells (CSC). The mechanism underlying the anticancer activity of ionophore agents can be related to their ability to form complexes with metal cations and transport them across cellular and subcellular membranes. Increasing evidence shows that the anticancer activity of polyether ionophores may be a consequence of the induction of apoptosis leading to apoptotic cell death, arresting cell cycle progression, induction of the cell oxidative stress, loss of mitochondrial membrane potential, reversion of MDR, synergistic anticancer effect with other anticancer drugs, etc. Continued investigation of the mechanisms of action and development of new polyether ionophores and their derivatives may provide more effective therapeutic drugs for cancer treatments. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Influence of the catheter-top-position upon the distribution pattern of continuous intra-arterially infused chemotherapeutic agent

    International Nuclear Information System (INIS)

    Ichinohe, Hyobu

    1980-01-01

    The whole body scanning showed the distribution pattern of infused drug in continuous intra-arterially infused chemotherapy by using a gamma camera and infused RI (sup(99m)Tc-MAA) from catheter. I measured the whole body scanning counts without shield (A) and with lead shield (B) on ROI and natural back ground counts (BG). Then I calculated the distribution ratio on ROI as following. [(A-B)/(A-BG)] x 100(%). It was easy to find a certain relation between the catheter-top-position and the distribution ratio. As a result of investigating data, there were about 4 catheter-top-positions in aorta. Case by case, we putted the catheter-top in better position and prevented technical side effects and measured roughly total dose on ROI. (author)

  20. Formulation development of smart gel periodontal drug delivery system for local delivery of chemotherapeutic agents with application of experimental design.

    Science.gov (United States)

    Dabhi, Mahesh R; Nagori, Stavan A; Gohel, Mukesh C; Parikh, Rajesh K; Sheth, Navin R

    2010-01-01

    Smart gel periodontal drug delivery systems (SGPDDS) containing gellan gum (0.1-0.8% w/v), lutrol F127 (14, 16, and 18% w/v), and ornidazole (1% w/v) were designed for the treatment of periodontal diseases. Each formulation was characterized in terms of in vitro gelling capacity, viscosity, rheology, content uniformity, in vitro drug release, and syringeability. In vitro gelation time and the nature of the gel formed in simulated saliva for prepared formulations showed polymeric concentration dependency. Drug release data from all formulations was fitted to different kinetic models and the Korsemeyer-Peppas model was the best fit model. Drug release was significantly decreased as the concentration of each polymer component was increased. Increasing the concentration of each polymeric component significantly increased viscosity, syringeability, and time for 50%, 70%, and 90% drug release. In conclusion, the formulations described offer a wide range of physical and drug release characteristics. The formulation containing 0.8% w/v of gellan gum and 16% w/v of lutrol F127 exhibited superior physical characteristics.

  1. Studies on the effects of ionizing radiation and chemotherapeutic agents on hematopoiesis according to the stem-cell kinetics

    International Nuclear Information System (INIS)

    Hirashima, Kunitake

    1975-01-01

    The fundamental problem of the effects of ionizing radiation and antineoplastic drugs on hematopoiesis can be explained by the kinetic study on the hematopoietic stem-cell population. Quantitative comparison of a single x-irradiation and a single administration of several antineoplastic drugs on the stem-cell population was performed by the splenic colony-forming method. The repopulation pattern of stem-cells in mice after a single 150 rad irradiation was compared with that after the administration of corresponding dose of cyclophosphamide. It was demonstrated that the additional administration of cyclophosphamide immediately after the x-irradiation significantly accelerated repopulation of the stem-cell compartment. The mechanism of repopulation of the stem-cell compartment after partial irradiation was also studied according to the immigration theory of stem-cells. An in vitro colony-forming technique for the human bone marrow cells was introduced and compared with other assay methods for stem-cells. From the hematological observations of accidentally irradiated patients, it was determined that the thromboelastogram values were regarded as one of the most useful indicators for detecting the earliest recovery sign of the hematopoietic stem-cells. (Evans, J.)

  2. Therapeutic Potential and Molecular Mechanisms of Emblica officinalis Gaertn in countering nephrotoxicity in rats induced by the chemotherapeutic agent cisplatin

    Directory of Open Access Journals (Sweden)

    Salma Malik

    2016-10-01

    Full Text Available Emblica officinalis Gaertn. belonging to family Euphorbiaceae is commonly known as Indian gooseberry or Amla in India. It is used as a ‘rejuvenating herb’ in traditional system of Indian medicine. It has been shown to possess antioxidant, anti-inflammatory and anti-apoptotic effects. Thus, on the basis of its biological effects, the present study was undertaken to evaluate the protective effect of the dried fruit extract of the E. Officinalis (EO in cisplatin-induced nephrotoxicity in rats and also to evaluate the mechanism of its nephroprotection. The study was done on male albino Wistar rats. They were divided into 6 groups (n=6 viz. control, cisplatin-control, cisplatin and EO (150, 300 and 600 mg/kg; p.o. respectively in different groups and EO only (600 mg/kg; p.o. only. EO was administered orally to the rats for a period of 10 days and on the 7th day, a single injection of cisplatin (8 mg/kg; i.p. was administered to the cisplatin-control and EO treatment groups. The rats were sacrificed on the 10th day. Cisplatin-control rats had deranged renal function parameters and the kidney histology confirmed the presence of acute tubular necrosis. Furthermore, there were increased oxidative stress, apoptosis and inflammation along with higher expression of MAPK pathway proteins in the rat kidney from the cisplatin-control group. Contrary to this, EO (600 mg/kg significantly normalized renal function, bolstered antioxidant status and ameliorated histological alterations. The inflammation and apoptosis were markedly lower in comparison to cisplatin-control rats. Furthermore, EO (600 mg/kg inhibited MAPK phosphorylation which was instrumental in preserving renal function and morphology. In conclusion, the results of our study demonstrated that EO attenuated cisplatin-induced nephrotoxicity in rats through suppression of MAPK induced inflammation and apoptosis.

  3. Developing Inhibitors of Translesion DNA Synthesis as Therapeutic Agents Against Lung Cancer

    Science.gov (United States)

    2014-10-01

    pol eta when replicating damaged DNA. 1S. SUBJECT TERMS: Mutagenesis, DNA polymerases, nucleoside analogs, chemotherapeutic agents 16. SECURITY ...such as polymerase eta, iota , and kappa that are involved in replicating damaged DNA. Our kinetic data obtained under Task 1B indicates that pol eta

  4. Pharmacological agents and impairment of fracture healing: what is the evidence?

    NARCIS (Netherlands)

    Pountos, I.; Georgouli, T.; Blokhuis, T.J.; Pape, H.C.; Giannoudis, P.V.

    2008-01-01

    Bone healing is an extremely complex process which depends on the coordinated action of several cell lineages on a cascade of biological events, and has always been a major medical concern. The use of several drugs such as corticosteroids, chemotherapeutic agents, non-steroidal anti-inflammatory

  5. Mitochondria and redox homoeostasis as chemotherapeutic targets of Araucaria angustifolia (Bert.) O. Kuntze in human larynx HEp-2 cancer cells.

    Science.gov (United States)

    Branco, Cátia dos Santos; de Lima, Émilin Dreher; Rodrigues, Tiago Selau; Scheffel, Thamiris Becker; Scola, Gustavo; Laurino, Claudia Cilene Fernandes Correia; Moura, Sidnei; Salvador, Mirian

    2015-04-25

    Natural products are among one of the most promising fields in finding new molecular targets in cancer therapy. Laryngeal carcinoma is one of the most common cancers affecting the head and neck regions, and is associated with high morbidity rate if left untreated. The aim of this study was to examine the antiproliferative effect of Araucaria angustifolia on laryngeal carcinoma HEp-2 cells. The results showed that A. angustifolia extract (AAE) induced a significant cytotoxicity in HEp-2 cells compared to the non-tumor human epithelial (HEK-293) cells, indicating a selective activity of AAE for the cancer cells. A. angustifolia extract was able to increase oxidative damage to lipids and proteins, and the production of nitric oxide, along with the depletion of enzymatic antioxidant defenses (superoxide dismutase and catalase) in the tumor cell line. Moreover, AAE was able to induce DNA damage, nuclear fragmentation and chromatin condensation. A significant increase in the Apoptosis Inducing Factor (AIF), Bax, poly-(ADP-ribose) polymerase (PARP) and caspase-3 cleavage expression were also found. These effects could be related to the ability of AAE to increase the production of reactive oxygen species through inhibition of the mitochondrial electron transport chain complex I activity and ATP production by the tumor cells. The phytochemical analysis of A. angustifolia, performed using High Resolution Mass Spectrometry (HRMS) in MS and MS/MS mode, showed the presence of dodecanoic and hexadecanoic acids, and phenolic compounds, which may be associated with the chemotherapeutic effect observed in this study. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. Neratinib reverses ATP-binding cassette B1-mediated chemotherapeutic drug resistance in vitro, in vivo, and ex vivo.

    Science.gov (United States)

    Zhao, Xiao-qin; Xie, Jing-dun; Chen, Xing-gui; Sim, Hong May; Zhang, Xu; Liang, Yong-ju; Singh, Satyakam; Talele, Tanaji T; Sun, Yueli; Ambudkar, Suresh V; Chen, Zhe-Sheng; Fu, Li-wu

    2012-07-01

    Neratinib, an irreversible inhibitor of epidermal growth factor receptor and human epidermal receptor 2, is in phase III clinical trials for patients with human epidermal receptor 2-positive, locally advanced or metastatic breast cancer. The objective of this study was to explore the ability of neratinib to reverse tumor multidrug resistance attributable to overexpression of ATP-binding cassette (ABC) transporters. Our results showed that neratinib remarkably enhanced the sensitivity of ABCB1-overexpressing cells to ABCB1 substrates. It is noteworthy that neratinib augmented the effect of chemotherapeutic agents in inhibiting the growth of ABCB1-overexpressing primary leukemia blasts and KBv200 cell xenografts in nude mice. Furthermore, neratinib increased doxorubicin accumulation in ABCB1-overexpressing cell lines and Rhodamine 123 accumulation in ABCB1-overexpressing cell lines and primary leukemia blasts. Neratinib stimulated the ATPase activity of ABCB1 at low concentrations but inhibited it at high concentrations. Likewise, neratinib inhibited the photolabeling of ABCB1 with [(125)I]iodoarylazidoprazosin in a concentration-dependent manner (IC(50) = 0.24 μM). Neither the expression of ABCB1 at the mRNA and protein levels nor the phosphorylation of Akt was affected by neratinib at reversal concentrations. Docking simulation results were consistent with the binding conformation of neratinib within the large cavity of the transmembrane region of ABCB1, which provides computational support for the cross-reactivity of tyrosine kinase inhibitors with human ABCB1. In conclusion, neratinib can reverse ABCB1-mediated multidrug resistance in vitro, ex vivo, and in vivo by inhibiting its transport function.

  7. Mastering JavaScript promises

    CERN Document Server

    Hussain, Muzzamil

    2015-01-01

    This book is for all the software and web engineers wanting to apply the promises paradigm to their next project and get the best outcome from it. This book also acts as a reference for the engineers who are already using promises in their projects and want to improve their current knowledge to reach the next level. To get the most benefit from this book, you should know basic programming concepts, have a familiarity with JavaScript, and a good understanding of HTML.

  8. Biomarker-guided repurposing of chemotherapeutic drugs for cancer therapy: a novel strategy in drug development

    Directory of Open Access Journals (Sweden)

    Jan eStenvang

    2013-12-01

    Full Text Available Cancer is a leading cause of mortality worldwide and matters are only set to worsen as its incidence continues to rise. Traditional approaches to combat cancer include improved prevention, early diagnosis, optimized surgery, development of novel drugs and honing regimens of existing anti-cancer drugs. Although discovery and development of novel and effective anti-cancer drugs is a major research area, it is well known that oncology drug development is a lengthy process, extremely costly and with high attrition rates. Furthermore, those drugs that do make it through the drug development mill are often quite expensive, laden with severe side-effects and, unfortunately, to date, have only demonstrated minimal increases in overall survival. Therefore, a strong interest has emerged to identify approved non-cancer drugs that possess anti-cancer activity, thus shortcutting the development process. This research strategy is commonly known as drug repurposing or drug repositioning and provides a faster path to the clinics. We have developed and implemented a modification of the standard drug repurposing strategy that we review here; rather than investigating target-promiscuous non-cancer drugs for possible anti-cancer activity, we focus on the discovery of novel cancer indications for already approved chemotherapeutic anti-cancer drugs. Clinical implementation of this strategy is normally commenced at clinical phase II trials and includes pre-treated patients. As the response rates to any non-standard chemotherapeutic drug will be relatively low in such a patient cohort it is a pre-requisite that such testing is based on predictive biomarkers. This review describes our strategy of biomarker-guided repurposing of chemotherapeutic drugs for cancer therapy, taking the repurposing of topoisomerase I inhibitors and topoisomerase I as a potential predictive biomarker as case in point.

  9. Increased Toxicity of Chemotherapeutic Drugs by All-Trans Retinoic Acid in Cd44 Cells

    Directory of Open Access Journals (Sweden)

    A Abbasi

    2016-03-01

    Full Text Available BACKGROUND AND OBJECTIVE: In recent studies, undifferentiated CD44 cells have been introduced as the major cause of chemotherapeutic drug resistance in esophageal cancer. In this study, we aimed to evaluate the effects of all-trans retinoic acid on reducing chemotherapeutic drug resistance and improving the associated toxic effects. METHODS: In this clinical study, CD44+ and CD44- cells were separated from KYSE-30 cell line, using magnetic-activated cell sorting (MACS method. The cytotoxic effects of retinoic acid treatment, combined with cisplatin and 5-fluorouracil, were separately evaluated in two cell groups, i.e., CD44+ and CD44-. Cytotoxicity was determined by identifying cellular metabolic activity, acridine orange/ethidium bromide staining, and flow cytometry. FINDINGS: In this study, CD44 marker was expressed in 6.25% of the cell population in KYSE-30 cell line. The results of flow cytometry revealed that treatment with a combination of retinoic acid and chemotherapeutic drugs could improve cell cycle arrest in CD44+ cells (p<0.05, unlike CD44- cells. Determination of cellular metabolic activity, increased cell apoptosis along with decreased half maximal inhibitory concentration (IC50, and acridine orange/ethidium bromide staining were indicative of the increased percentage of primary and secondary apoptotic CD44+ cells. However, in CD44- cells, these effects were only observed by using a combination of retinoic acid and cisplatin (p<0.05. CONCLUSION: The present results showed that all-trans retinoic acid could increase the toxicity of cisplatin and 5-fluorouracil in CD44+ cells.

  10. Up-regulated Ectonucleotidases in Fas-Associated Death Domain Protein- and Receptor-Interacting Protein Kinase 1-Deficient Jurkat Leukemia Cells Counteract Extracellular ATP/AMP Accumulation via Pannexin-1 Channels during Chemotherapeutic Drug-Induced Apoptosis.

    Science.gov (United States)

    Boyd-Tressler, Andrea M; Lane, Graham S; Dubyak, George R

    2017-07-01

    Pannexin-1 (Panx1) channels mediate the efflux of ATP and AMP from cancer cells in response to induction of extrinsic apoptosis by death receptors or intrinsic apoptosis by chemotherapeutic agents. We previously described the accumulation of extracellular ATP /AMP during chemotherapy-induced apoptosis in Jurkat human leukemia cells. In this study, we compared how different signaling pathways determine extracellular nucleotide pools in control Jurkat cells versus Jurkat lines that lack the Fas-associated death domain (FADD) or receptor-interacting protein kinase 1 (RIP1) cell death regulatory proteins. Tumor necrosis factor- α induced extrinsic apoptosis in control Jurkat cells and necroptosis in FADD-deficient cells; treatment of both lines with chemotherapeutic drugs elicited similar intrinsic apoptosis. Robust extracellular ATP/AMP accumulation was observed in the FADD-deficient cells during necroptosis, but not during apoptotic activation of Panx1 channels. Accumulation of extracellular ATP/AMP was similarly absent in RIP1-deficient Jurkat cells during apoptotic responses to chemotherapeutic agents. Apoptotic activation triggered equivalent proteolytic gating of Panx1 channels in all three Jurkat cell lines. The differences in extracellular ATP/AMP accumulation correlated with cell-line-specific expression of ectonucleotidases that metabolized the released ATP/AMP. CD73 mRNA, and α β -methylene-ADP-inhibitable ecto-AMPase activity were elevated in the FADD-deficient cells. In contrast, the RIP1-deficient cells were defined by increased expression of tartrate-sensitive prostatic acid phosphatase as a broadly acting ectonucleotidase. Thus, extracellular nucleotide accumulation during regulated tumor cell death involves interplay between ATP/AMP efflux pathways and different cell-autonomous ectonucleotidases. Differential expression of particular ectonucleotidases in tumor cell variants will determine whether chemotherapy-induced activation of Panx1 channels

  11. ERC/mesothelin as a marker for chemotherapeutic response in patients with mesothelioma.

    Science.gov (United States)

    Tajima, Ken; Hirama, Michihiro; Shiomi, Kazu; Ishiwata, Toshiji; Yoshioka, Masataka; Iwase, Akihiko; Iwakami, Shinichiro; Yamazaki, Mariko; Toba, Michie; Tobino, Kazunori; Sugano, Koji; Ichikawa, Masako; Hagiwara, Yoshiaki; Takahashi, Kazuhisa; Hino, Okio

    2008-01-01

    It has been recently reported that soluble mesothelin-related protein (SMRP), serum mesothelin, and osteopontin (OPN) are considered as relevant biomarkers for the diagnosis of mesothelioma. The aim of this study was to investigate whether serum N-ERC/mesothelin, an NH3-terminal fragment of mesothelin, and plasma OPN reflect chemotherapeutic effect in patients with mesothelioma. Serum N-ERC/mesothelin and plasma osteopontin were determined with a sandwich enzyme-linked immunosorbent assay (ELISA) system. The average N-ERC ratio, determined by dividing the N-ERC levels following chemotherapy by those prior to chemotherapy, in the partial response (PR) group was significantly lower than that of the stable disease (SD)/progressive disease (PD) group. In contrast, the average OPN ratio, determined by dividing the OPN levels following chemotherapy by those prior to chemotherapy, in the PR group was not statistically different from that of the SD/PD group. N-ERC/mesothelin is considered as relevant in monitoring chemotherapeutic response in patients with mesothelioma.

  12. Is There an Opportunity for Current Chemotherapeutics to Up-regulate MIC-A/B Ligands?

    Directory of Open Access Journals (Sweden)

    Kendel Quirk

    2017-10-01

    Full Text Available Natural killer (NK cells are critical effectors of the immune system. NK cells recognize unhealthy cells by specific ligands [e.g., MHC- class I chain related protein A or B (MIC-A/B] for further elimination by cytotoxicity. Paradoxically, cancer cells down-regulate MIC-A/B and evade NK cell’s anticancer activity. Recent data indicate that cellular-stress induces MIC-A/B, leading to enhanced sensitivity of cancer cells to NK cell-mediated cytotoxicity. In this Perspective article, we hypothesize that current chemotherapeutics at sub-lethal, non-toxic dose may promote cellular-stress and up-regulate the expression of MIC-A/B ligands to augment cancer’s sensitivity to NK cell-mediated cytotoxicity. Preliminary data from two human breast cancer cell lines, MDA-MB-231 and T47D treated with clinically relevant therapeutics such as doxorubicin, paclitaxel and methotrexate support the hypothesis. The goal of this Perspective is to underscore the prospects of current chemotherapeutics in NK cell immunotherapy, and discuss potential challenges and opportunities to improve cancer therapy.

  13. Activation of multiple chemotherapeutic prodrugs by the natural enzymolome of tumour-localised probiotic bacteria.

    Science.gov (United States)

    Lehouritis, Panos; Stanton, Michael; McCarthy, Florence O; Jeavons, Matthieu; Tangney, Mark

    2016-01-28

    Some chemotherapeutic drugs (prodrugs) require activation by an enzyme for efficacy. We and others have demonstrated the ability of probiotic bacteria to grow specifically within solid tumours following systemic administration, and we hypothesised that the natural enzymatic activity of these tumour-localised bacteria may be suitable for activation of certain such chemotherapeutic drugs. Several wild-type probiotic bacteria; Escherichia coli Nissle, Bifidobacterium breve, Lactococcus lactis and Lactobacillus species, were screened against a panel of popular prodrugs. All strains were capable of activating at least one prodrug. E. coli Nissle 1917 was selected for further studies because of its ability to activate numerous prodrugs and its resistance to prodrug toxicity. HPLC data confirmed biochemical transformation of prodrugs to their toxic counterparts. Further analysis demonstrated that different enzymes can complement prodrug activation, while simultaneous activation of multiple prodrugs (CB1954, 5-FC, AQ4N and Fludarabine phosphate) by E. coli was confirmed, resulting in significant efficacy improvement. Experiments in mice harbouring murine tumours validated in vitro findings, with significant reduction in tumour growth and increase in survival of mice treated with probiotic bacteria and a combination of prodrugs. These findings demonstrate the ability of probiotic bacteria, without the requirement for genetic modification, to enable high-level activation of multiple prodrugs specifically at the site of action. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. The combination of reduced MCL-1 and standard chemotherapeutics is tolerable in mice.

    Science.gov (United States)

    Brinkmann, Kerstin; Grabow, Stephanie; Hyland, Craig D; Teh, Charis E; Alexander, Warren S; Herold, Marco J; Strasser, Andreas

    2017-12-01

    A common therapeutic strategy to combat human cancer is the use of combinations of drugs, each targeting different cellular processes or vulnerabilities. Recent studies suggest that addition of an MCL-1 inhibitor to such anticancer drug treatments could be an attractive therapeutic strategy. Thus, it is of great interest to understand whether combinations of conventional anticancer drugs with an MCL-1 inhibitor will be tolerable and efficacious. In order to mimic the combination of MCL-1 inhibition with other cancer therapeutics, we treated Mcl-1 +/- heterozygous mice, which have a ~50% reduction in MCL-1 protein in their cells, with a broad range of chemotherapeutic drugs. Careful monitoring of treated mice revealed that a wide range of chemotherapeutic drugs had no significant effect on the general well-being of Mcl-1 +/- mice with no overt damage to a broad range of tissues, including the haematopoietic compartment, heart, liver and kidney. These results indicate that MCL-1 inhibition may represent a tolerable strategy in cancer therapy, even when combined with select cytotoxic drugs.

  15. Characterization of the microDNA through the response to chemotherapeutics in lymphoblastoid cell lines.

    Directory of Open Access Journals (Sweden)

    Pamela Mehanna

    Full Text Available Recently, a new class of extrachromosomal circular DNA, called microDNA, was identified. They are on average 100 to 400 bp long and are derived from unique non-repetitive genomic regions with high gene density. MicroDNAs are thought to arise from DNA breaks associated with RNA metabolism or replication slippage. Given the paucity of information on this entirely novel phenomenon, we aimed to get an additional insight into microDNA features by performing the microDNA analysis in 20 independent human lymphoblastoid cell lines (LCLs prior and after treatment with chemotherapeutic drugs. The results showed non-random genesis of microDNA clusters from the active regions of the genome. The size periodicity of 190 bp was observed, which matches DNA fragmentation typical for apoptotic cells. The chemotherapeutic drug-induced apoptosis of LCLs increased both number and size of clusters further suggesting that part of microDNAs could result from the programmed cell death. Interestingly, proportion of identified microDNA sequences has common loci of origin when compared between cell line experiments. While compatible with the original observation that microDNAs originate from a normal physiological process, obtained results imply complementary source of its production. Furthermore, non-random genesis of microDNAs depicted by redundancy between samples makes these entities possible candidates for new biomarker generation.

  16. A novel chemotherapeutic sensitivity-testing system based on collagen gel droplet embedded 3D-culture methods for hepatocellular carcinoma.

    Science.gov (United States)

    Hou, Jun; Hong, Zhixian; Feng, Fan; Chai, Yantao; Zhang, Yunkai; Jiang, Qiyu; Hu, Yan; Wu, Shunquan; Wu, Yingsong; Gao, Xunian; Chen, Qiong; Wan, Yong; Bi, Jingfeng; Zhang, Zheng

    2017-11-08

    Patients suffering from advanced stage hepatocellular carcinoma (HCC) often exhibit a poor prognosis or dismal clinical outcomes due to ineffective chemotherapy or a multi-drug resistance (MDR) process. Thus, it is urgent to develop a new chemotherapeutic sensitivity testing system for HCC treatment. The presence study investigated the potential application of a novel chemotherapeutic sensitivity-testing system based on a collagen gel droplet embedded 3D-culture system (CD-DST). Primary cells were separating from surgical resection specimens and then tested by CD-DST. To identify whether HCC cell lines or cells separating from clinical specimens contain MDR features, the cells were treated with an IC 50 (half maximal inhibitory concentration) or IC max (maximal inhibitory concentration) concentration of antitumor agents, e.g., 5-furuolouracil (5-FU), paclitaxel (PAC), cisplatin (CDDP), epirubicin (EPI), or oxaliplatin (L-OHP), and the inhibitory rates (IRs) were calculated. HepG2 cells were sensitive to 5-FU, PAC, CDDP, EPI, or L-OHP; the IC 50 value is 0.83 ± 0.45 μg/ml, 0.03 ± 0.02 μg/ml, 1.15 ± 0.75 μg/ml, 0.09 ± 0.03 μg/ml, or 1.76 ± 0.44 μg/ml, respectively. Only eight (8/26), nine (9/26), or five (5/26) patients were sensitive to the IC max concentration of CDDP, EPI, or L-OHP; whereas only three (3/26), four (4/26), or two (2/26) patients were sensitive to the IC 50 concentration of CDDP, EPI, or L-OHP. No patients were sensitive to 5-FU or PAC. The in vitro drug sensitivity exanimation revealed the MDR features of HCC and examined the sensitivity of HCC cells from clinical specimens to anti-tumor agents. CD-DST may be a useful method to predict the potential clinical benefits of anticancer agents for HCC patients.

  17. Nuclear energy: obstacles and promises

    International Nuclear Information System (INIS)

    Bacher, P.

    2003-01-01

    Nuclear energy has distinctive merits (sustainable resources, low costs, no greenhouse gases) but its development must overcome serious hurdles (fear of accidents, radio-phobia, waste management). The large unit size of present-day reactors is compatible only with large electrical grids, and involves a high capital cost. Taking into account these different factors, the paper outlines how nuclear energy may contribute to the reduction of greenhouse gases, and which are the most promising developments. (author)

  18. The promise of cyborg intelligence.

    Science.gov (United States)

    Brown, Michael F; Brown, Alexander A

    2017-03-01

    Yu et al. (2016) demonstrated that algorithms designed to find efficient routes in standard mazes can be integrated with the natural processes controlling rat navigation and spatial choices, and they pointed out the promise of such "cyborg intelligence" for biorobotic applications. Here, we briefly describe Yu et al.'s work, explore its relevance to the study of comparative cognition, and indicate how work involving cyborg intelligence would benefit from interdisciplinary collaboration between behavioral scientists and engineers.

  19. Freedom: A Promise of Possibility.

    Science.gov (United States)

    Bunkers, Sandra Schmidt

    2015-10-01

    The idea of freedom as a promise of possibility is explored in this column. The core concepts from a research study on considering tomorrow (Bunkers, 1998) coupled with humanbecoming community change processes (Parse, 2003) are used to illuminate this notion. The importance of intentionality in human freedom is discussed from both a human science and a natural science perspective. © The Author(s) 2015.

  20. Identification and characterization of SSE15206, a microtubule depolymerizing agent that overcomes multidrug resistance

    KAUST Repository

    Manzoor, Safia

    2018-02-13

    Microtubules are highly dynamic structures that form spindle fibres during mitosis and are one of the most validated cancer targets. The success of drugs targeting microtubules, however, is often limited by the development of multidrug resistance. Here we describe the discovery and characterization of SSE15206, a pyrazolinethioamide derivative [3-phenyl-5-(3,4,5-trimethoxyphenyl)-4,5-dihydro-1H-pyrazole-1-carbothioamide] that has potent antiproliferative activities in cancer cell lines of different origins and overcomes resistance to microtubule-targeting agents. Treatment of cells with SSE15206 causes aberrant mitosis resulting in G2/M arrest due to incomplete spindle formation, a phenotype often associated with drugs that interfere with microtubule dynamics. SSE15206 inhibits microtubule polymerization both in biochemical and cellular assays by binding to colchicine site in tubulin as shown by docking and competition studies. Prolonged treatment of cells with the compound results in apoptotic cell death [increased Poly (ADP-ribose) polymerase cleavage and Annexin V/PI staining] accompanied by p53 induction. More importantly, we demonstrate that SSE15206 is able to overcome resistance to chemotherapeutic drugs in different cancer cell lines including multidrug-resistant KB-V1 and A2780-Pac-Res cell lines overexpressing MDR-1, making it a promising hit for the lead optimization studies to target multidrug resistance.

  1. SERIES: Genomic instability in cancer Balancing repair and tolerance of DNA damage caused by alkylating agents

    Science.gov (United States)

    Fu, Dragony; Calvo, Jennifer A.; Samson, Leona D

    2013-01-01

    Alkylating agents comprise a major class of frontline chemotherapeutic drugs that inflict cytotoxic DNA damage as their main mode of action, in addition to collateral mutagenic damage. Numerous cellular pathways, including direct DNA damage reversal, base excision repair (BER), and mismatch repair (MMR) respond to alkylation damage to defend against alkylation-induced cell death or mutation. However, maintaining a proper balance of activity both within and between these pathways is crucial for an organism's favorable response to alkylating agents. Furthermore, an individual's response to alkylating agents can vary considerably from tissue to tissue and from person to person, pointing to genetic and epigenetic mechanisms that modulate alkylating agent toxicity. PMID:22237395

  2. Chemical Agents

    Science.gov (United States)

    ... CR) see Riot Control Agents Digitalis Distilled mustard (HD) see Sulfur mustard E Ethylene glycol F Fentanyls and other opioids H Hydrazine Hydrofluoric acid (hydrogen fluoride) Hydrogen chloride Hydrogen cyanide (AC) Hydrogen ...

  3. Chemotherapy-induced pulmonary hypertension: role of alkylating agents.

    Science.gov (United States)

    Ranchoux, Benoît; Günther, Sven; Quarck, Rozenn; Chaumais, Marie-Camille; Dorfmüller, Peter; Antigny, Fabrice; Dumas, Sébastien J; Raymond, Nicolas; Lau, Edmund; Savale, Laurent; Jaïs, Xavier; Sitbon, Olivier; Simonneau, Gérald; Stenmark, Kurt; Cohen-Kaminsky, Sylvia; Humbert, Marc; Montani, David; Perros, Frédéric

    2015-02-01

    Pulmonary veno-occlusive disease (PVOD) is an uncommon form of pulmonary hypertension (PH) characterized by progressive obstruction of small pulmonary veins and a dismal prognosis. Limited case series have reported a possible association between different chemotherapeutic agents and PVOD. We evaluated the relationship between chemotherapeutic agents and PVOD. Cases of chemotherapy-induced PVOD from the French PH network and literature were reviewed. Consequences of chemotherapy exposure on the pulmonary vasculature and hemodynamics were investigated in three different animal models (mouse, rat, and rabbit). Thirty-seven cases of chemotherapy-associated PVOD were identified in the French PH network and systematic literature analysis. Exposure to alkylating agents was observed in 83.8% of cases, mostly represented by cyclophosphamide (43.2%). In three different animal models, cyclophosphamide was able to induce PH on the basis of hemodynamic, morphological, and biological parameters. In these models, histopathological assessment confirmed significant pulmonary venous involvement highly suggestive of PVOD. Together, clinical data and animal models demonstrated a plausible cause-effect relationship between alkylating agents and PVOD. Clinicians should be aware of this uncommon, but severe, pulmonary vascular complication of alkylating agents. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  4. Chitin fulfilling a biomaterials promise

    CERN Document Server

    Khor, Eugene

    2001-01-01

    The second edition of Chitin underscores the important factors for standardizing chitin processing and characterization. It captures the essential interplay between chitin's assets and limitations as a biomaterial, placing the past promises of chitin in perspective, addressing its present realities and offering insight into what is required to realize chitin's destiny (including its derivative, chitosan) as a biomaterial of the twenty-first century. This book is an ideal guide for both industrialists and researchers with a vested interest in commercializing chitin.An upd

  5. Multi-agent Cooperation in a Planning Framework

    NARCIS (Netherlands)

    De Weerdt, M.M.; Bos, A.; Tonino, J.F.M.; Witteveen, C.

    2000-01-01

    The promise of multi-agent systems is that multiple agents can solve problems more efficiently than single agents can. In this paper we propose a method to implement cooperation between agents in the planning phase, in order to achive more cost-effective solutions than without cooperation. Two

  6. Organoruthenium Complexes with CN Ligands are Highly Potent Cytotoxic Agents that Act by a New Mechanism of Action

    Czech Academy of Sciences Publication Activity Database

    Novohradský, Vojtěch; Yellol, J.; Stuchlíková, O.; Santana, M.D.; Kostrhunová, Hana; Yellol, G.; Kašpárková, Jana; Bautista, D.; Ruiz, J.; Brabec, Viktor

    2017-01-01

    Roč. 23, č. 61 (2017), s. 15294-15299 ISSN 0947-6539 R&D Projects: GA ČR(CZ) GA17-05302S Institutional support: RVO:68081707 Keywords : chemotherapeutic-agents * ruthenium(ii) complexes * iridium(iii) complexes Subject RIV: CE - Biochemistry OBOR OECD: Biochemistry and molecular biology Impact factor: 5.317, year: 2016

  7. Investigation of the possibility of the reduction of chemotherapeutics by activation of PBMCs in tumor cell

    International Nuclear Information System (INIS)

    Schwanninger, M.

    2009-01-01

    The three big columns in the treatment of malignant tumour are chemotherapeutics, radiotherapy and surgical interventions. However, beside these three types of therapies the hormone therapy plays an extremely important role as well. In modern medicine chemotherapeutics are the main therapy for most malignant tumour diseases. This fact mainly follows from the absence of other, just as well working alternatives. Administration of these substances sometimes leads to strong undesirable side effects or to insufficient response. The mentioned lack of alternatives, neither in the form of chemotherapeutics nor in the form of other possibilities of treatment, can heavily endanger the desired therapy success. Today it is clear that there is a complicated teamwork between immune defence, inflammation and carcinoma. Up to twenty times more Macrophages are located in tumour surroundings than in healthy fabric. These so called tumour associated or M2 Macrophages (TAMs) differ from other Macrophages, the M1 Macrophages, by their non-inflammatory effects. They do not necessarily lead to immune defence. In 2008, Hunder et al described in a study that cloned CD4+ T cells injected in Melanoma lead to a remission of the tumour. An activation of PBMCs and subsequent administration could be helpful with the fight against malignant tumours. Using the Δ;NS virus PBMCs will be stimulated - more exactly, monocytes and as a result PBMCs - and initiate an immunological reaction against tumour cells. Furthermore it will be shown that PBMCs immunosuppressed earlier - as they appear in tumour surroundings - can be activated by means of Δ;NS virus again. The 'tumour friendly' environment may be altered in a 'tumour-unfriendly' environment, and, as a direct consequence, the growth of the tumour cells will decrease. It is clear that this activation of the immune system cannot substitute a chemotherapy as a whole, but an improved killing or reduction of the dose should lead to the reduction of the

  8. Epigenetics of oropharyngeal squamous cell carcinoma: opportunities for novel chemotherapeutic targets.

    Science.gov (United States)

    Lindsay, Cameron; Seikaly, Hadi; Biron, Vincent L

    2017-01-31

    Epigenetic modifications are heritable changes in gene expression that do not directly alter DNA sequence. These modifications include DNA methylation, histone post-translational modifications, small and non-coding RNAs. Alterations in epigenetic profiles cause deregulation of fundamental gene expression pathways associated with carcinogenesis. The role of epigenetics in oropharyngeal squamous cell carcinoma (OPSCC) has recently been recognized, with implications for novel biomarkers, molecular diagnostics and chemotherapeutics. In this review, important epigenetic pathways in human papillomavirus (HPV) positive and negative OPSCC are summarized, as well as the potential clinical utility of this knowledge.This material has never been published and is not currently under evaluation in any other peer-reviewed publication.

  9. Clinical developments of chemotherapeutic nanomedicines: Polymers and liposomes for delivery of camptothecins and platinum (II) drugs

    KAUST Repository

    Kieler-Ferguson, Heidi M.

    2013-01-17

    For the past 40 years, liposomal and polymeric delivery vehicles have been studied as systems capable of modulating the cytotoxicity of small molecule chemotherapeutics, increasing tumor bearing animal survival times, and improving drug targeting. Although a number of macromolecular-drug conjugates have progressed to clinical trials, tuning drug release to maintain efficacy in conjunction with controlling drug toxicity has prevented the clinical adoption of many vehicles. In this article, we review the motivations for and approaches to polymer and liposomal delivery with regard to camptothecin and cisplatin delivery. WIREs Nanomed Nanobiotechnol 2013, 5:130-138. doi: 10.1002/wnan.1209 For further resources related to this article, please visit the WIREs website. Conflict of interest: Drs Kieler-Ferguson and Fréchet declare no conflicts of interest. Dr Szoka is the founder of a liposome drug delivery company that is not working on any of the compounds mentioned in this article. © 2013 Wiley Periodicals, Inc.

  10. Urinary schistosomiasis among schoolchildren in Yemen: prevalence, risk factors, and the effect of a chemotherapeutic intervention.

    Science.gov (United States)

    Al-Waleedi, Ali A; El-Nimr, Nessrin A; Hasab, Ali A; Bassiouny, Hassan K; Al-Shibani, Latifa A

    2013-12-01

    Schistosomiasis is one of the most important public health problems in Yemen. The prevalence of urinary schistosomiasis varies considerably across different parts of Yemen and was estimated to be 10% among schoolchildren in Sana'a. Praziquantel (PZQ) is highly effective against all five major human species of schistosomes. The aim of the present work was to estimate the prevalence of urinary schistosomiasis, describe the risk factors associated with its endemicity, and implement and assess a chemotherapeutic intervention using PZQ in a village in Yemen. The sample included 696 schoolchildren from a village in Abyan Governorate. During the baseline school survey, personal, sociodemographic, and environmental data, and data on practices in relation to water contact were collected from each study participant using a predesigned structured questionnaire. Urine samples from each participant were examined for macrohematuria and the presence of Schistosoma haematobium eggs. The chemotherapeutic intervention was assessed 3 and 6 months after the treatment and certain indicators were calculated. The prevalence of S. haematobium was 18.1%. The main significant risk factors were male sex; proximity of houses to water ponds; and using pond water for swimming, agricultural activities, and for bathing in houses. PZQ treatment reduced the prevalence of infection and decreased the prevalence of high-intensity infection. Survival analysis showed that the probability of residual infection also dropped after the treatment intervention. Male sex and using pond water for various activities were the main significant risk factors associated with urinary schistosomiasis. PZQ is still a cornerstone drug in reducing or eliminating morbidity associated with schistosomiasis infection. Health education programs tailored for the community are required for the control and prevention of urinary schistosomiasis. To address schoolchildren, school curricula should include lessons about urinary

  11. MFTF-progress and promise

    International Nuclear Information System (INIS)

    Thomassen, K.I.

    1980-01-01

    The Mirror Fusion Test Facility (MFTF) has been in construction at Lawrence Livermore National Laboratory (LLNL) for 3 years, and most of the major subsystems are nearing completion. Recently, the scope of this project was expanded to meet new objectives, principally to reach plasma conditions corresponding to energy break-even. To fulfill this promise, the single-cell minimum-B mirror configuration will be replaced with a tandem mirror configuration (MFTF-B). The facility must accordingly be expanded to accomodate the new geometry. This paper briefly discusses the status of the major MFTF subsystems and describes how most of the technological objectives of MFTF will be demonstrated before we install the additional systems necessary to make the tandem. It also summarizes the major features of the expanded facility

  12. The promising opportunity of dismantlement

    International Nuclear Information System (INIS)

    Anon.

    2009-01-01

    Civil engineering, mechanics and waste conditioning companies are thriving around the market of nuclear facilities dismantlement which is promised to a huge development in the coming decade. This paper presents a map of the opportunities of the dismantlement market throughout Europe (research and power reactors, fuel fabrication plants, spent fuel reprocessing plants) and a cost estimation of a given dismantling work with respect to the different steps of the work. In France a small core of about twenty companies is involved in nuclear dismantlement but the French market is also looking towards foreign specialists of this activity. The British market is also targeted by the French companies but for all the actors the technological or commercial advance gained today will be determining for the future markets. (J.S.)

  13. Chemotherapeutics and radiation stimulate MHC class I expression through elevated interferon-beta signaling in breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Shan Wan

    Full Text Available Low doses of anticancer drugs have been shown to enhance antitumor immune response and increase the efficacy of immunotherapy. The molecular basis for such effects remains elusive, although selective depletion of T regulatory cells has been demonstrated. In the current studies, we demonstrate that topotecan (TPT, a topoisomerase I-targeting drug with a well-defined mechanism of action, stimulates major histocompatibility complex class I (MHC I expression in breast cancer cells through elevated expression/secretion of interferon-β (IFN-β and activation of type I IFN signaling. First, we show that TPT treatment elevates the expression of both total and cell-surface MHC I in breast cancer cells. Second, conditioned media from TPT-treated breast cancer ZR-75-1 cells induce elevated expression of cell-surface MHC I in drug-naïve recipient cells, suggesting the involvement of cytokines and/or other secreted molecules. Consistently, TPT-treated cells exhibit elevated expression of multiple cytokines such as IFN-β, TNF-α, IL-6 and IL-8. Third, either knocking down the type I interferon receptor subunit 1 (IFNAR1 or addition of neutralizing antibody against IFN-β results in reduced MHC I expression in TPT-treated cells. Together, these results suggest that TPT induces increased IFN-β autocrine/paracrine signaling through type I IFN receptor, resulting in the elevated MHC I expression in tumor cells. Studies have also demonstrated that other chemotherapeutic agents (e.g. etoposide, cisplatin, paclitaxel and vinblastine similarly induce increased IFN-β secretion and elevated MHC I expression. In addition, conditioned media from γ-irradiated donor cells are shown to induce IFN-β-dependent MHC I expression in unirradiated recipient cells. In the aggregate, our results suggest that many cancer therapeutics induce elevated tumor antigen presentation through MHC I, which could represent a common mechanism for enhanced antitumor immune response through

  14. Bioavailability of curcumin: problems and promises.

    Science.gov (United States)

    Anand, Preetha; Kunnumakkara, Ajaikumar B; Newman, Robert A; Aggarwal, Bharat B

    2007-01-01

    Curcumin, a polyphenolic compound derived from dietary spice turmeric, possesses diverse pharmacologic effects including anti-inflammatory, antioxidant, antiproliferative and antiangiogenic activities. Phase I clinical trials have shown that curcumin is safe even at high doses (12 g/day) in humans but exhibit poor bioavailability. Major reasons contributing to the low plasma and tissue levels of curcumin appear to be due to poor absorption, rapid metabolism, and rapid systemic elimination. To improve the bioavailability of curcumin, numerous approaches have been undertaken. These approaches involve, first, the use of adjuvant like piperine that interferes with glucuronidation; second, the use of liposomal curcumin; third, curcumin nanoparticles; fourth, the use of curcumin phospholipid complex; and fifth, the use of structural analogues of curcumin (e.g., EF-24). The latter has been reported to have a rapid absorption with a peak plasma half-life. Despite the lower bioavailability, therapeutic efficacy of curcumin against various human diseases, including cancer, cardiovascular diseases, diabetes, arthritis, neurological diseases and Crohn's disease, has been documented. Enhanced bioavailability of curcumin in the near future is likely to bring this promising natural product to the forefront of therapeutic agents for treatment of human disease.

  15. Chemotherapeutic-Induced Cardiovascular Dysfunction: Physiological Effects, Early Detection—The Role of Telomerase to Counteract Mitochondrial Defects and Oxidative Stress

    Science.gov (United States)

    Quryshi, Nabeel; Norwood Toro, Laura E.; Ait-Aissa, Karima; Kong, Amanda; Beyer, Andreas M.

    2018-01-01

    Although chemotherapeutics can be highly effective at targeting malignancies, their ability to trigger cardiovascular morbidity is clinically significant. Chemotherapy can adversely affect cardiovascular physiology, resulting in the development of cardiomyopathy, heart failure and microvascular defects. Specifically, anthracyclines are known to cause an excessive buildup of free radical species and mitochondrial DNA damage (mtDNA) that can lead to oxidative stress-induced cardiovascular apoptosis. Therefore, oncologists and cardiologists maintain a network of communication when dealing with patients during treatment in order to treat and prevent chemotherapy-induced cardiovascular damage; however, there is a need to discover more accurate biomarkers and therapeutics to combat and predict the onset of cardiovascular side effects. Telomerase, originally discovered to promote cellular proliferation, has recently emerged as a potential mechanism to counteract mitochondrial defects and restore healthy mitochondrial vascular phenotypes. This review details mechanisms currently used to assess cardiovascular damage, such as C-reactive protein (CRP) and troponin levels, while also unearthing recently researched biomarkers, including circulating mtDNA, telomere length and telomerase activity. Further, we explore a potential role of telomerase in the mitigation of mitochondrial reactive oxygen species and maintenance of mtDNA integrity. Telomerase activity presents a promising indicator for the early detection and treatment of chemotherapy-derived cardiac damage. PMID:29534446

  16. The anti-tumour properties and biodistribution (as determined by the radiolabeled equivalent) of Au-compounds intended as potential chemotherapeutics

    Energy Technology Data Exchange (ETDEWEB)

    Nell, M.J. [Department of Pharmacology, University of Pretoria, P.O. Box 2034, Pretoria 0001 (South Africa); Wagener, J.M. [Radiochemistry, NECSA (South African Nuclear Energy Corporation Ltd.), P.O. Box 582, Pretoria 0001 (South Africa)], E-mail: jwagener@necsa.co.za; Zeevaart, J.R. [CARST, North West University, Mafikeng Campus, P. Bag X2046, Mmabatho 2735 (South Africa); Kilian, E. [Department of Pharmacology, Onderstepoort, University of Pretoria, P.O. Box 2034, Pretoria 0001 (South Africa); Mamo, M.A.; Layh, M. [Molecular Sciences Institute, School of Chemistry, University of the Witwatersrand, Private Bag 3, Wits, 2050 Johannesburg (South Africa); Coyanis, M. [Project AuTEK, Mintek, Private Bag X3015, Randburg 2125 (South Africa); Rensburg, C.E.J. van [Department of Pharmacology, University of Pretoria, P.O. Box 2034, Pretoria 0001 (South Africa)

    2009-07-15

    The anti-tumour activity of the Au (I) phosphine complex [Au(dppe{sub 2}]Cl was first discovered in the mid 1980s although promising results were obtained it did not pass clinical studies because of its toxicity to organs such as the liver and heart. The aim of this study was to determine whether the two novel gold compounds (MM5 and MM6), selected for this study, have higher selectivity for cancer cells with less toxicity towards normal cells than [Au(dppe){sub 2}]Cl, and also to determine whether they have improved bio distribution compared to [Au(dppe){sub 2}]Cl. The Au-compounds as potential chemotherapeutic drugs were evaluated by using radioactive tracers in the in vitro and in vivo studies. Results obtained from these experiments showed that the uptake of these experimental compounds was dependent on their octanol/water partition coefficient. However; the inhibition of cell growth did not correlate with the uptake of these compounds by the cells that were tested. In terms of the total uptake it was found that the compounds that were less lipophilic (MM5, MM6) were taken up less efficiently in cells than those that are more lipophilic. Therefore hydrophilic drugs are expected to have a limited biodistribution compared to lipophilic drugs. This might imply a more selective tumour uptake.

  17. Chemotherapeutic potential of 17-AAG against cutaneous leishmaniasis caused by Leishmania (Viannia) braziliensis.

    Science.gov (United States)

    Santos, Diego M; Petersen, Antonio L O A; Celes, Fabiana S; Borges, Valeria M; Veras, Patricia S T; de Oliveira, Camila I

    2014-10-01

    Leishmaniasis remains a worldwide public health problem. The limited therapeutic options, drug toxicity and reports of resistance, reinforce the need for the development of new treatment options. Previously, we showed that 17-(allylamino)-17-demethoxygeldanamycin (17-AAG), a Heat Shock Protein 90 (HSP90)-specific inhibitor, reduces L. (L.) amazonensis infection in vitro. Herein, we expand the current knowledge on the leishmanicidal activity of 17-AAG against cutaneous leishmaniasis, employing an experimental model of infection with L. (V.) braziliensis. Exposure of axenic L. (V.) braziliensis promastigotes to 17-AAG resulted in direct dose-dependent parasite killing. These results were extended to L. (V.) braziliensis-infected macrophages, an effect that was dissociated from the production of nitric oxide (NO), superoxide (O(-2)) or inflammatory mediators such as TNF-α, IL-6 and MCP-1. The leishmanicidal effect was then demonstrated in vivo, employing BALB/c mice infected with L. braziliensis. In this model, 17-AAG treatment resulted in smaller skin lesions and parasite counts were also significantly reduced. Lastly, 17-AAG showed a similar effect to amphotericin B regarding the ability to reduce parasite viability. 17-AAG effectively inhibited the growth of L. braziliensis, both in vitro and in vivo. Given the chronicity of L. (V.) braziliensis infection and its association with mucocutaneous leishmaniasis, 17-AAG can be envisaged as a new chemotherapeutic alternative for cutaneous Leishmaniasis.

  18. The intervention research on treatment by Xianchen to rabbits model of chemotherapeutic phlebitis.

    Science.gov (United States)

    Zhang, Jing; Shen, Juan; Yin, Weiwei; Wei, Xiaoyu; Wu, Ligao; Liu, Hao

    2016-08-01

    To develop a chemotherapeutics induced phlebitis and explore the effects of Xianchen on the phlebitis treatment. Forty-eight rabbits were divided into two series. Phlebitis model induced by vincristine was established at each series. The first series had 24 rabbits, which were divided into four groups (6 hours, 12 hours, 18 hours, 24 hours) after vincristine infusion. The grades of phlebitis through visual observation and histopathological examination were observed. The second series had also 24 rabbits. Interventions were performed 12 hours after vincristine infusion. These rabbits were randomly divided into four groups, according to treatment: Hirudoid (bid), Xianchen (daily), Xianchen (tid), Xianchen (five times a day). Four days after intervention, the venous injury through visual observation and histopathological examination were evaluated. Series 1: Phlebitis appeared 12 hours after infusion of vincristine through visual observation. There was a significant difference (pphlebitis appeared early. Xianchen can treat vincristine induced phlebitis, as well as Hirudoid. It is particularly effective in the treatment of edema, and there is a remarkable dose-response relationship.

  19. Chemotherapeutic potential of diazeniumdiolate-based aspirin prodrugs in breast cancer.

    Science.gov (United States)

    Basudhar, Debashree; Cheng, Robert C; Bharadwaj, Gaurav; Ridnour, Lisa A; Wink, David A; Miranda, Katrina M

    2015-06-01

    Diazeniumdiolate-based aspirin prodrugs have previously been shown to retain the anti-inflammatory properties of aspirin while protecting against the common side effect of stomach ulceration. Initial analysis of two new prodrugs of aspirin that also release either nitroxyl (HNO) or nitric oxide (NO) demonstrated increased cytotoxicity toward human lung carcinoma cells compared to either aspirin or the parent nitrogen oxide donor. In addition, cytotoxicity was significantly lower in endothelial cells, suggesting cancer-specific sensitivity. To assess the chemotherapeutic potential of these new prodrugs in treatment of breast cancer, we studied their effect both in cultured cells and in a nude mouse model. Both prodrugs reduced growth of breast adenocarcinoma cells more effectively than the parent compounds while not being appreciably cytotoxic in a related nontumorigenic cell line (MCF-10A). The HNO donor also was more cytotoxic than the related NO donor. The basis for the observed specificity was investigated in terms of impact on metabolism, DNA damage and repair, apoptosis, angiogenesis and metastasis. The results suggest a significant pharmacological potential for treatment of breast cancer. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Quantitative evaluation of thallium-201 uptake in predicting chemotherapeutic response of osteosarcoma

    International Nuclear Information System (INIS)

    Lin, J.; Leung Waitong; Ho, S.K.W.; Ho, K.C.; Kumta, S.M.; Metreweli, C.; Johnson, P.J.

    1995-01-01

    This study attempts to quantitate changes in tumour to normal tissue ratio following chemotherapy. Eight consecutive patients with classical osteosarcoma received standard preoperative chemotherapy with a combination of cisplatin, adriamycin and high-dose methotrexate. 201 Tl gamma scintigraphic images were obtained both before and after chemotherapy. The average counts taken over the tumour divided by that from the contralateral normal tissue area yielded a tumour-to-normal tissue (T/N) ratio. The percentage change in the T/N ratio before and after preoperative chemotherapy was correlated with the percentage of tumour necrosis from pathological section. The median post-chemotherapy T/N ratio was 1.85 (range 0.5-7.7). The median percentage change in T/N ratio after chemotherapy was -58% (range +26% to -83%). The median percentage of necrosis from pathological section was 80% (range 0%-95%). There was a good correlation between the percentage of tumour necrosis and the percentage change in T/N ratio (rank correlation coefficient r=0.84, P=0.0085). Quantitative assessment of changes in 201 Tl uptake by osteosarcoma correlates well with tumour necrosis after preoperative chemotherapy. This method may be used to predict response to chemotherapy at an earlier stage, enabling the clinician to consider alternative chemotherapeutic regimens or salvage surgery. (orig.)

  1. Synergistic effects of plasma-activated medium and chemotherapeutic drugs in cancer treatment

    Science.gov (United States)

    Chen, Chao-Yu; Cheng, Yun-Chien; Cheng, Yi-Jing

    2018-04-01

    Chemotherapy is an important treatment method for metastatic cancer, but the drug-uptake efficiency of cancer cells needs to be enhanced in order to diminish the side effects of chemotherapeutic drugs and improve survival. The use of a nonequilibrium low-temperature atmospheric-pressure plasma jet (APPJ) has been demonstrated to exert selective effects in cancer therapy and to be able to enhance the uptake of molecules by cells, which makes an APPJ a good candidate adjuvant in combination chemotherapy. This study estimated the effects of direct helium-based APPJ (He-APPJ) exposure (DE) and He-APPJ-activated RPMI medium (PAM) on cell viability and migration. Both of these treatments decreased cell viability and inhibited cell migration, but to different degrees in different cell types. The use of PAM as a culture medium resulted in the dialkylcarbocyanine (DiI) fluorescent dye entering the cells more efficiently. PAM was combined with the anticancer drug doxorubicin (Doxo) to treat human heptocellular carcinoma HepG2 cells and human adenocarcinomic alveolar basal epithelial A549 cells. The results showed that the synergistic effects of combined PAM and Doxo treatment resulted in stronger lethality in cancer cells than did PAM or Doxo treatment alone. To sum up, PAM has potential as an adjuvant in combination with other drugs to improve curative cancer therapies.

  2. Transgenic Plants as Low-Cost Platform for Chemotherapeutic Drugs Screening

    Directory of Open Access Journals (Sweden)

    Daniele Vergara

    2015-01-01

    Full Text Available In this work we explored the possibility of using genetically modified Arabidopsis thaliana plants as a rapid and low-cost screening tool for evaluating human anticancer drugs action and efficacy. Here, four different inhibitors with a validated anticancer effect in humans and distinct mechanism of action were screened in the plant model for their ability to interfere with the cytoskeletal and endomembrane networks. We used plants expressing a green fluorescent protein (GFP tagged microtubule-protein (TUA6-GFP, and three soluble GFPs differently sorted to reside in the endoplasmic reticulum (GFPKDEL or to accumulate in the vacuole through a COPII dependent (AleuGFP or independent (GFPChi mechanism. Our results demonstrated that drugs tested alone or in combination differentially influenced the monitored cellular processes including cytoskeletal organization and endomembrane trafficking. In conclusion, we demonstrated that A. thaliana plants are sensitive to the action of human chemotherapeutics and can be used for preliminary screening of drugs efficacy. The cost-effective subcellular imaging in plant cell may contribute to better clarify drugs subcellular targets and their anticancer effects.

  3. Overexpression of xeroderma pigmentosum group C decreases the chemotherapeutic sensitivity of colorectal carcinoma cells to cisplatin.

    Science.gov (United States)

    Zhang, Yi; Cao, Jia; Meng, Yanni; Qu, Chunying; Shen, Feng; Xu, Leiming

    2018-05-01

    Xeroderma pigmentosum group C (XPC) is a DNA-damage-recognition gene active at the early stage of DNA repair. XPC also participates in regulation of cell-cycle checkpoint and DNA-damage-induced apoptosis. In the present study, the expression levels of genes involved in nucleotide excision repair (NER) were assessed in human colorectal cancer (CRC) tissue. This analysis revealed that expression of XPC mRNA significantly increased in colorectal carcinoma tissues compared with matched normal controls. Expression of XPC gradually increased along with the degree of progression of CRC. In vitro , an XTT assay demonstrated that small interfering RNA (siRNA) targeting XPC significantly increased the sensitivity of CRC SW480 cells to cisplatin, whereas cells transfected with a XPC-overexpression plasmid became more resistant to cisplatin. Furthermore, flow cytometry revealed that the proportion of apoptotic cells significantly increased in XPC-knockdown cells upon cisplatin treatment. However, the overexpression XPC significantly increased the resistance of cells to cisplatin. In vivo , tumor growth was significantly reduced in tumor-bearing mice when the XPC gene was knocked down. Upregulation of the expression of pro-apoptotic Bcl-associated X and downregulation of the anti-apoptotic B-cell lymphoma 2 proteins was observed in the implanted tumor tissue. In conclusion, XPC serves a key role in chemotherapeutic sensitivity of CRC to cisplatin, meaning that it may be a potential target for chemotherapy of CRC.

  4. NOVP: a novel chemotherapeutic regimen with minimal toxicity for treatment of Hodgkin's disease

    Energy Technology Data Exchange (ETDEWEB)

    Hagemeister, F.B.; Cabanillas, F.; Velasquez, W.S.; Meistrich, M.L.; Liang, J.C.; McLaughlin, P.; Redman, J.R.; Romaguera, J.E.; Rodriguez, M.A.; Swan, F. Jr. (Univ. of Texas, M.D. Anderson Cancer Center, Houston (USA))

    1990-12-01

    Patients with early-staged Hodgkin's disease have had a higher relapse rate following radiotherapy alone if they have B symptoms, large mediastinal masses, hilar involvement, or stage III disease. From June 1988 to December 1989, 27 previously untreated patients with early-staged Hodgkin's disease with adverse features for disease-free survival received combined-modality therapy. Seventeen patients had stage I or II disease, 10 had stage III, 5 had B symptoms, 13 had large mediastinal masses, and 6 had peripheral masses measuring 10 cm or more in diameter. All patients initially received three cycles of a novel chemotherapeutic regimen combining Novantrone (mitoxantrone, American Cyanamid Company), vincristine, vinblastine, and prednisone (NOVP). Twenty-four patients with clinically staged I or II disease with adverse features or stage III disease did not undergo laparotomy; three patients had favorable stage I or II disease and at laparotomy had stage III disease. Radiotherapy-treatment fields depended on the extent of nodal involvement. Twenty-six patients completed all therapy as planned to complete remission (CR) and one of these has had progression; she is in second CR following additional radiotherapy. With a median follow-up of 12 months, all patients are alive. Tolerance to treatment was excellent with only grade 1 or 2 nausea, alopecia and myalgias, and brief myelosuppression. NOVP is an effective adjuvant chemotherapy regimen for inducing responses, with minimal toxicity, prior to definitive radiotherapy for patients with early-staged Hodgkin's disease.

  5. Using adaptive model predictive control to customize maintenance therapy chemotherapeutic dosing for childhood acute lymphoblastic leukemia.

    Science.gov (United States)

    Noble, Sarah L; Sherer, Eric; Hannemann, Robert E; Ramkrishna, Doraiswami; Vik, Terry; Rundell, Ann E

    2010-06-07

    Acute lymphoblastic leukemia (ALL) is a common childhood cancer in which nearly one-quarter of patients experience a disease relapse. However, it has been shown that individualizing therapy for childhood ALL patients by adjusting doses based on the blood concentration of active drug metabolite could significantly improve treatment outcome. An adaptive model predictive control (MPC) strategy is presented in which maintenance therapy for childhood ALL is personalized using routine patient measurements of red blood cell mean corpuscular volume as a surrogate for the active drug metabolite concentration. A clinically relevant mathematical model is developed and used to describe the patient response to the chemotherapeutic drug 6-mercaptopurine, with some model parameters being patient-specific. During the course of treatment, the patient-specific parameters are adaptively identified using recurrent complete blood count measurements, which sufficiently constrain the patient parameter uncertainty to support customized adjustments of the drug dose. While this work represents only a first step toward a quantitative tool for clinical use, the simulated treatment results indicate that the proposed mathematical model and adaptive MPC approach could serve as valuable resources to the oncologist toward creating a personalized treatment strategy that is both safe and effective. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  6. Trading Agents

    CERN Document Server

    Wellman, Michael

    2011-01-01

    Automated trading in electronic markets is one of the most common and consequential applications of autonomous software agents. Design of effective trading strategies requires thorough understanding of how market mechanisms operate, and appreciation of strategic issues that commonly manifest in trading scenarios. Drawing on research in auction theory and artificial intelligence, this book presents core principles of strategic reasoning that apply to market situations. The author illustrates trading strategy choices through examples of concrete market environments, such as eBay, as well as abst

  7. Assessment of genetic integrity, splenic phagocytosis and cell death potential of (Z-4-((1,5-dimethyl-3-oxo-2-phenyl-2,3dihydro-1H-pyrazol-4-yl amino-4-oxobut-2-enoic acid and its effect when combined with commercial chemotherapeutics

    Directory of Open Access Journals (Sweden)

    Rodrigo Juliano Oliveira

    2018-02-01

    Full Text Available Abstract The increased incidence of cancer and its high treatment costs have encouraged the search for new compounds to be used in adjuvant therapies for this disease. This study discloses the synthesis of (Z-4-((1,5-dimethyl-3-oxo-2-phenyl-2,3dihydro-1H-pyrazol-4-yl amino-4-oxobut-2-enoic acid (IR-01 and evaluates not only the action of this compound on genetic integrity, increase in splenic phagocytosis and induction of cell death but also its effects in combination with the commercial chemotherapeutic agents doxorubicin, cisplatin and cyclophosphamide. IR-01 was designed and synthesized based on two multifunctionalyzed structural fragments: 4-aminoantipyrine, an active dipyrone metabolite, described as an antioxidant and anti-inflammatory agent; and the pharmacophore fragment 1,4-dioxo-2-butenyl, a cytotoxic agent. The results indicated that IR-01 is an effective chemoprotector because it can prevent clastogenic and/or aneugenic damage, has good potential to prevent genomic damage, can increase splenic phagocytosis and lymphocyte frequency and induces cell death. However, its use as an adjuvant in combination with chemotherapy is discouraged since IR-01 interferes in the effectiveness of the tested chemotherapeutic agents. This is a pioneer study as it demonstrates the chemopreventive effects of IR-01, which may be associated with the higher antioxidant activity of the precursor structure of 4-aminoantipyrine over the effects of the 1,4-dioxo-2-butenyl fragment.

  8. Balancing repair and tolerance of DNA damage caused by alkylating agents

    OpenAIRE

    Fu, Dragony; Calvo, Jennifer A.; Samson, Leona D.

    2012-01-01

    Alkylating agents constitute a major class of frontline chemotherapeutic drugs that inflict cytotoxic DNA damage as their main mode of action, in addition to collateral mutagenic damage. Numerous cellular pathways, including direct DNA damage reversal, base excision repair (BER) and mismatch repair (MMR), respond to alkylation damage to defend against alkylation-induced cell death or mutation. However, maintaining a proper balance of activity both within and between these pathways is crucial ...

  9. SERIES: Genomic instability in cancer Balancing repair and tolerance of DNA damage caused by alkylating agents

    OpenAIRE

    Fu, Dragony; Calvo, Jennifer A.; Samson, Leona D

    2012-01-01

    Alkylating agents comprise a major class of frontline chemotherapeutic drugs that inflict cytotoxic DNA damage as their main mode of action, in addition to collateral mutagenic damage. Numerous cellular pathways, including direct DNA damage reversal, base excision repair (BER), and mismatch repair (MMR) respond to alkylation damage to defend against alkylation-induced cell death or mutation. However, maintaining a proper balance of activity both within and between these pathways is crucial fo...

  10. 18-F-FDG PET-CT in Monitoring of Chemotherapeutic Effect in a Case of Metastatic Hepatic Epithelioid Hemangioendothelioma.

    Science.gov (United States)

    Shamim, Shamim Ahmed; Tripathy, Sarthak; Mukherjee, Anirban; Bal, Chandrasekhar; Roy, Shambo Guha

    2017-01-01

    Hepatic epithelioid hemangioendothelioma is a rare variant of mesenchymal tumor. Surgical resection or partial hepatectomy is the treatment of choice in the case of localized disease. However, in metastatic cases, chemotherapeutic drugs targeting the tyrosine kinase are being used. We hereby present 18-F-fludeoxyglucose positron emission tomography-computed tomography findings in a case of a 35-year old woman with metastatic HEHE showing significant response to Sorafenib therapy after 6 months.

  11. Sensitization of human carcinoma cells to alkylating agents by small interfering RNA suppression of 3-alkyladenine-DNA glycosylase.

    Science.gov (United States)

    Paik, Johanna; Duncan, Tod; Lindahl, Tomas; Sedgwick, Barbara

    2005-11-15

    One of the major cytotoxic lesions generated by alkylating agents is DNA 3-alkyladenine, which can be excised by 3-alkyladenine DNA glycosylase (AAG). Inhibition of AAG may therefore result in increased cellular sensitivity to chemotherapeutic alkylating agents. To investigate this possibility, we have examined the role of AAG in protecting human tumor cells against such agents. Plasmids that express small interfering RNAs targeted to two different regions of AAG mRNA were transfected into HeLa cervical carcinoma cells and A2780-SCA ovarian carcinoma cells. Stable derivatives of both cell types with low AAG protein levels were sensitized to alkylating agents. Two HeLa cell lines with AAG protein levels reduced by at least 80% to 90% displayed a 5- to 10-fold increase in sensitivity to methyl methanesulfonate, N-methyl-N-nitrosourea, and the chemotherapeutic drugs temozolomide and 1,3-bis(2-chloroethyl)-1-nitrosourea. These cells showed no increase in sensitivity to UV light or ionizing radiation. After treatment with methyl methanesulfonate, AAG knockdown HeLa cells were delayed in S phase but accumulated in G2-M. Our data support the hypothesis that ablation of AAG activity in human tumor cells may provide a useful strategy to enhance the efficacy of current chemotherapeutic regimens that include alkylating agents.

  12. The influence of toxicity constraints in models of chemotherapeutic protocol escalation

    KAUST Repository

    Boston, E. A. J.; Gaffney, E. A.

    2011-01-01

    between drug administrations are reduced. To maintain a manageable scope in our studies, we focus on a single cell cycle phase-specific agent with uncomplicated pharmacokinetics, as motivated by 5-Fluorouracil-based adjuvant treatments of liver

  13. Risk factors determining chemotherapeutic toxicity in patients with advanced colorectal cancer

    NARCIS (Netherlands)

    Jansman, FGA; Sleijfer, DT; Coenen, JLLM; De Graaf, JC; Brouwers, JRBJ

    2000-01-01

    Antitumour therapy in advanced colorectal cancer has limited efficacy. For decades, fluorouracil has been the main anticancer drug for the treatment of colorectal cancer. Recently, however, new agents have been introduced: raltitrexed, irinotecan and oxaliplatin. Currently, the dosage for an

  14. Resistance to chemotherapeutic antimetabolites: a function of salvage pathway involvement and cellular response to DNA damage.

    OpenAIRE

    Kinsella, A. R.; Smith, D.; Pickard, M.

    1997-01-01

    The inherent or acquired (induced) resistance of certain tumours to cytotoxic drug therapy is a major clinical problem. There are many categories of cytotoxic agent: the antimetabolites, e.g. methotrexate (MTX), N-phosphonacetyl-L-aspartate (PALA), 5-fluorouracil (5-FU), 6-mercaptopurine (6-TG), hydroxyurea (HU) and 1-beta-D-arabinofuranosylcytosine (AraC); the alkylating agents, e.g. the nitrogen mustards and nitrosoureas; the antibiotics, e.g. doxorubicin and mitomycin C; the plant alkaloid...

  15. Laboratory determination of chemotherapeutic drug resistance in tumor cells from patients with leukemia, using a fluorometric microculture cytotoxicity assay (FMCA).

    Science.gov (United States)

    Larsson, R; Kristensen, J; Sandberg, C; Nygren, P

    1992-01-21

    An automated fluorometric microculture cytotoxicity assay (FMCA) based on the measurement of fluorescence generated from cellular hydrolysis of fluorescein diacetate (FDA) to fluorescein was employed for chemotherapeutic-drug-sensitivity testing of tumor-cell suspensions from patients with leukemia. Fluorescence was linearly related to cell number, and reproducible measurements of drug sensitivity could be performed using fresh or cryopreserved leukemia cells. A marked heterogeneity with respect to chemotherapeutic drug sensitivity was observed for a panel of cytotoxic drugs tested in 43 samples from 35 patients with treated or untreated acute and chronic leukemia. For samples obtained from patients with chronic lymphocytic and acute myelocytic leukemia, sensitivity profiles for standard drugs corresponded to known clinical activity and the assay detected primary and acquired drug resistance. Individual in vitro/in vivo correlations indicated high specificity with respect to the identification of drug resistance. The results suggest that the FMCA may be a simple and rapid method for in vivo-representative determinations of chemotherapeutic drug resistance in tumor cells obtained from patients with leukemia.

  16. Radioprotective Agents

    Directory of Open Access Journals (Sweden)

    Ilker Kelle

    2008-01-01

    Full Text Available Since1949, a great deal of research has been carried out on the radioprotective activity of various chemical substances. Thiol compounds, compounds which contain –SH radical, different classes of pharmacological agents and other compounds such as vitamine C and WR-2721 have been shown to reduce mortality when administered prior to exposure to a lethal dose of radiation. Recently, honey bee venom as well as that of its components melittin and histamine have shown to be valuable in reduction of radiation-induced damage and also provide prophylactic alternative treatment for serious side effects related with radiotherapy. It has been suggested that the radioprotective activity of bee venom components is related with the stimulation of the hematopoetic system.

  17. Pharmacogenetic characterization of naturally occurring germline NT5C1A variants to chemotherapeutic nucleoside analogs

    Science.gov (United States)

    Saliba, Jason; Zabriskie, Ryan; Ghosh, Rajarshi; Powell, Bradford C; Hicks, Stephanie; Kimmel, Marek; Meng, Qingchang; Ritter, Deborah I; Wheeler, David A; Gibbs, Richard A; Tsai, Francis T F; Plon, Sharon E

    2016-01-01

    Background Mutations or alteration in expression of the 5’ nucleotidase gene family can confer altered responses to treatment with nucleoside analogs. While investigating leukemia susceptibility genes, we discovered a very rare p.L254P NT5C1A missense variant in the substrate recognition motif. Given the paucity of cellular drug response data from NT5C1A germline variation, we characterized p.L254P and eight rare variants of NT5C1A from genomic databases. Methods Through lentiviral infection, we created HEK293 cell lines that stably overexpress wildtype NT5C1A, p.L254P, or eight NT5C1A variants reported in the NHLBI Exome Variant server (one truncating and seven missense). IC50 values were determined by cytotoxicity assays after exposure to chemotherapeutic nucleoside analogs (Cladribine, Gemcitabine, 5-Fluorouracil). In addition, we used structure-based homology modeling to generate a 3D model for the C-terminal region of NT5C1A. Results The p.R180X (truncating), p.A214T, and p.L254P missense changes were the only variants that significantly impaired protein function across all nucleotide analogs tested (>5-fold difference versus WT; p<.05). Several of the remaining variants individually displayed differential effects (both more and less resistant) across the analogs tested. The homology model provided a structural framework to understand the impact of NT5C1A mutants on catalysis and drug processing. The model predicted active site residues within NT5C1A motif III and we experimentally confirmed that p.K314 (not p.K320) is required for NT5C1A activity. Conclusion We characterized germline variation and predicted protein structures of NT5C1A. Individual missense changes showed substantial variation in response to the different nucleoside analogs tested, which may impact patients’ responses to treatment. PMID:26906009

  18. Advanced Mucinous Colorectal Cancer: Epidemiology, Prognosis and Efficacy of Chemotherapeutic Treatment.

    Science.gov (United States)

    Ott, Claudia; Gerken, Michael; Hirsch, Daniela; Fest, Petra; Fichtner-Feigl, Stefan; Munker, Stefan; Schnoy, Elisabeth; Stroszczynski, Christian; Vogelhuber, Martin; Herr, Wolfgang; Evert, Matthias; Reng, Michael; Schlitt, Hans Jürgen; Klinkhammer-Schalke, Monika; Teufel, Andreas

    2018-06-05

    The clinicopathological significance of the mucinous subtype of colorectal cancer (CRC) remains controversial. As of today, none of the current guidelines differentiate treatment with respect to mucinous or nonmucinous cancer. Due to the lack of substantiated data, best treatment remains unclear and the mucinous subtype of CRC is usually treated along the lines of recommendations for adenocarcinoma of the colon. We investigated an East-Bavarian cohort of 8,758 patients with CRC. These included 613 (7.0%) patients with a mucinous subtype, who were analyzed for assessing their characteristics in clinical course and for evaluating the efficacy of common chemotherapy protocols. Mucinous CRC was predominantly located in the right hemicolon; it was diagnosed at more advanced stages and occurred with preponderance in women. A higher rate of G3/4 grading was observed at diagnosis (all p < 0.001). An association of mucinous CRC with younger age at initial diagnosis, previously reported by other groups, could not be confirmed. Patients with mucinous stage IV colon cancer demonstrated poorer survival (p = 0.006). In contrast, no differences in survival were observed for specific stages I-III colon cancer. Stage-dependent analysis of rectal cancer stages I-IV also showed no differences in survival. However, univariable overall analysis resulted in significant poorer survival of mucinous compared to nonmucinous rectal cancer (p = 0.029). Also, combined analysis of all patients with mucinous CRC revealed poorer overall survival (OS) of these patients compared to nonmucinous CRC patients (median 48.4 vs. 60.2 months, p = 0.049) but not in multivariable analysis (p = 0.089). Chemotherapeutic treatment showed comparable efficacy regarding OS for mucinous and nonmucinous cancers in both an adjuvant and palliative setting for colon cancer patients (p values comparing mucinous and nonmucinous cancers < 0.001-0.005). © 2018 S. Karger AG, Basel.

  19. Odds of death after glioblastoma diagnosis in the United States by chemotherapeutic era

    International Nuclear Information System (INIS)

    Wachtel, Mitchell S; Yang, Shengping

    2014-01-01

    Bevacizumab (BZM) and temozolomide (TMZ) have been shown to be beneficial in the treatment of patients with glioblastoma. We sought evidence for the benefit of BZM in the general patient population at large. The Surveillance, Epidemiology, and End Results SEER database was queried for patients diagnosed with glioblastoma between 2000 and 2009, divided into a pre-TMZ era (January 2000–June 2003), a transitional era (July 2003–March 2005), a TMZ era (April 2005–October 2007), and a BZM-TMZ era (November 2007–December 2009). Binomial logit regression analyzed odds of death, taking into account age at diagnosis, tumor size, gender, race, marital status, radiotherapy, and extensive surgery. Compared with the pre-TMZ era, odds of death were decreased in the TMZ era by 12% (97.5% CI [confidence interval] 3–20%) 6 months after diagnosis and 36% (30–42%) a year after diagnosis; corresponding values for BZM-TMZ were 31% (24–37%) and 50% (45–55%). For era comparisons, decreases in odds of death were larger at 12 than 6 months; the opposite was true for extensive surgery and radiotherapy (P < 0.025, Wald χ 2 test, for each analysis). For both 6 and 12 month comparisons, odds of death in the BZM-TMZ era were lower than in the TMZ era (P < 0.025, Wald χ 2 test, for each analysis). The results provide evidence that TMZ positively impacted survival of glioblastoma patients and that the addition of BZM further improved survival, this lends support to the addition of BZM to the chemotherapeutic armamentarium. Evaluation of odds of death is an attractive alternative to Cox regression when proportional hazards assumptions are violated and follow-up is good

  20. Targeting aerobic glycolysis: 3-bromopyruvate as a promising anticancer drug.

    Science.gov (United States)

    Cardaci, Simone; Desideri, Enrico; Ciriolo, Maria Rosa

    2012-02-01

    The Warburg effect refers to the phenomenon whereby cancer cells avidly take up glucose and produce lactic acid under aerobic conditions. Although the molecular mechanisms underlying tumor reliance on glycolysis remains not completely clear, its inhibition opens feasible therapeutic windows for cancer treatment. Indeed, several small molecules have emerged by combinatorial studies exhibiting promising anticancer activity both in vitro and in vivo, as a single agent or in combination with other therapeutic modalities. Therefore, besides reviewing the alterations of glycolysis that occur with malignant transformation, this manuscript aims at recapitulating the most effective pharmacological therapeutics of its targeting. In particular, we describe the principal mechanisms of action and the main targets of 3-bromopyruvate, an alkylating agent with impressive antitumor effects in several models of animal tumors. Moreover, we discuss the chemo-potentiating strategies that would make unparalleled the putative therapeutic efficacy of its use in clinical settings.

  1. Long-term exposure to estrogen enhances chemotherapeutic efficacy potentially through epigenetic mechanism in human breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Yu-Wei Chang

    Full Text Available Chemotherapy is the most common clinical option for treatment of breast cancer. However, the efficacy of chemotherapy depends on the age of breast cancer patients. Breast tissues are estrogen responsive and the levels of ovarian estrogen vary among the breast cancer patients primarily between pre- and post-menopausal age. Whether this age-dependent variation in estrogen levels influences the chemotherapeutic efficacy in breast cancer patients is not known. Therefore, the objective of this study was to evaluate the effects of natural estrogen 17 beta-estradiol (E2 on the efficacy of chemotherapeutic drugs in breast cancer cells. Estrogen responsive MCF-7 and T47D breast cancer cells were long-term exposed to 100 pg/ml estrogen, and using these cells the efficacy of chemotherapeutic drugs doxorubicin and cisplatin were determined. The result of cell viability and cell cycle analysis revealed increased sensitivities of doxorubicin and cisplatin in estrogen-exposed MCF-7 and T47D cells as compared to their respective control cells. Gene expression analysis of cell cycle, anti-apoptosis, DNA repair, and drug transporter genes further confirmed the increased efficacy of chemotherapeutic drugs in estrogen-exposed cells at molecular level. To further understand the role of epigenetic mechanism in enhanced chemotherapeutic efficacy by estrogen, cells were pre-treated with epigenetic drugs, 5-aza-2-deoxycytidine and Trichostatin A prior to doxorubicin and cisplatin treatments. The 5-aza-2 deoxycytidine pre-treatment significantly decreased the estrogen-induced efficacy of doxorubicin and cisplatin, suggesting the role of estrogen-induced hypermethylation in enhanced sensitivity of these drugs in estrogen-exposed cells. In summary, the results of this study revealed that sensitivity to chemotherapy depends on the levels of estrogen in breast cancer cells. Findings of this study will have clinical implications in selecting the chemotherapy strategies for

  2. Study on chemotherapeutic sensitizing effect of nimotuzumab on different human esophageal squamous carcinoma cells.

    Science.gov (United States)

    Yang, Xiaoyu; Ji, Yinghua; Kang, Xiaochun; Chen, Meiling; Kou, Weizheng; Jin, Cailing; Lu, Ping

    2016-02-01

    Esophageal cancer is one of the leading causes of mortality worldwide. Although, surgery, radio- and chemotherapy are used to treat the disease, the identification of new drugs is crucial to increase the curative effect. The aim of the present study was to examine the chemotherapeutic sensitizing effect of nimotuzumab (h-R3) and cisplatin cytotoxic drugs cisplatin (DDP) and 5-fluorouracil (5-FU) on esophageal carcinoma cells with two different epidermal growth factor receptor (EGFR) expressions. The expression of EGFR was detected in the human EC1 or EC9706 esophageal squamous cell carcinoma cell line using immunohistochemistry. The inhibitory effect of DDP and 5-FU alone or combined with h-R3 on EC1 or EC9706 cell proliferation was detected using an MTT assay. Flow cytometry and the TUNEL assay were used to determine the effect of single or combined drug treatment on cell apoptosis. The results showed that the expression of EGFR was low in EC1 cells but high in EC9706 cells. The inhibitory effect of the single use of h-R3 on EC1 or EC9706 cell proliferation was decreased. The inhibitory effect between single use of h-R3 alone and combined use of the chemotherapy drugs showed no statistically significant difference (P>0.05) on the EC1 cell growth rate, but showed a statistically significant difference (a=0.05) on EC9706 cell growth rate. The results detected by flow cytometry and TUNEL assay showed that the difference between single use of h-R3 alone and the control group was statistically significant with regard to the EC1 apoptosis rate effect (P0.05). However, statistically significant differences were identified in the apoptotic rate of EC9706 cells between the h-R3 combined chemotherapy group and single chemotherapy group (P0.05). In conclusion, the sensitization effect of h-R3 on chemotherapy drugs is associated with the expression level of EGFR in EC1 or EC9706 cells. The cell killing effect of the combined use of h-R3 with DDP and 5-FU showed no obvious

  3. Realizing the promises of marine biotechnology

    NARCIS (Netherlands)

    Luiten, EEM; Akkerman, [No Value; Koulman, A; Kamermans, P; Reith, H; Barbosa, MJ; Sipkema, D; Wijffels, RH

    High-quality research in the field of marine biotechnology is one of the key-factors for successful innovation in exploiting the vast diversity of marine life. However, fascinating scientific research with promising results and claims on promising potential applications (e.g. for pharmaceuticals,

  4. Realizing the promises of marine biotechnology

    NARCIS (Netherlands)

    Luiten, E.E.M.; Akkerman, I.; Koulman, A.; Kamermans, P.; Reith, H.; Barbosa, M.J.; Sipkema, D.; Wijffels, R.H.

    2003-01-01

    High-quality research in the field of marine biotechnology is one of the key-factors for successful innovation in exploiting the vast diversity of marine life. However, fascinating scientific research with promising results and claims on promising potential applications (e.g. for pharmaceuticals,

  5. Tennessee Promise: A Response to Organizational Change

    Science.gov (United States)

    Littlepage, Ben; Clark, Teresa; Wilson, Randal; Stout, Logan

    2018-01-01

    Community colleges in Tennessee, either directly or indirectly, experienced unprecedented change as a result of Tennessee Promise. The present study explored how student support service administrators at three community colleges responded to organizational change as a result of the Tennessee Promise legislation. Investigators selected community…

  6. The combination of BH3-mimetic ABT-737 with the alkylating agent temozolomide induces strong synergistic killing of melanoma cells independent of p53.

    Directory of Open Access Journals (Sweden)

    Steven N Reuland

    Full Text Available Metastatic melanoma has poor prognosis and is refractory to most conventional chemotherapies. The alkylating agent temozolomide (TMZ is commonly used in treating melanoma but has a disappointing response rate. Agents that can act cooperatively with TMZ and improve its efficacy are thus highly sought after. The BH3 mimetic ABT-737, which can induce apoptosis by targeting pro-survival Bcl-2 family members, has been found to enhance the efficacy of many conventional chemotherapeutic agents in multiple cancers. We found that combining TMZ and ABT-737 induced strong synergistic apoptosis in multiple human melanoma cell lines. When the drugs were used in combination in a mouse xenograft model, they drastically reduced tumor growth at concentrations where each individual drug had no significant effect. We found that TMZ treatment elevated p53 levels, and that the pro-apoptotic protein Noxa was elevated in TMZ/ABT-737 treated cells. Experiments with shRNA demonstrated that the synergistic effect of TMZ and ABT-737 was largely dependent on Noxa. Experiments with nutlin-3, a p53 inducer, demonstrated that p53 induction was sufficient for synergistic cell death with ABT-737 in a Noxa-dependent fashion. However, p53 was not necessary for TMZ/ABT-737 synergy as demonstrated by a p53-null line, indicating that TMZ and ABT-737 together induce Noxa in a p53-independent fashion. These results demonstrate that targeting anti-apoptotic Bcl-2 members is a promising method for treating metastatic melanoma, and that clinical trials with TMZ and Bcl-2 inhibitors are warranted.

  7. Nanomedicine for cancer therapy from chemotherapeutic to hyperthermia-based therapy

    CERN Document Server

    Kumar, Piyush

    2017-01-01

    This Brief focuses on the cancer therapy available till date, from conventional drug delivery to nanomedicine in clinical trial. In addition, it reports on future generation based nanotherapeutics and cancer theranostic agent for effective therapeutic diagnosis and treatment. Breast cancer was chosen as the model system in this review. The authors give emphasis to multiple drug resistance (MDR) and its mechanism and how to overcome it using the nanoparticle approach. .

  8. Delivery of chemotherapeutics across the blood-brain barrier: challenges and advances.

    Science.gov (United States)

    Doolittle, Nancy D; Muldoon, Leslie L; Culp, Aliana Y; Neuwelt, Edward A

    2014-01-01

    The blood-brain barrier (BBB) limits drug delivery to brain tumors. We utilize intraarterial infusion of hyperosmotic mannitol to reversibly open the BBB by shrinking endothelial cells and opening tight junctions between the cells. This approach transiently increases the delivery of chemotherapy, antibodies, and nanoparticles to brain. Our preclinical studies have optimized the BBB disruption (BBBD) technique and clinical studies have shown its safety and efficacy. The delivery of methotrexate-based chemotherapy in conjunction with BBBD provides excellent outcomes in primary central nervous system lymphoma (PCNSL) including stable or improved cognitive function in survivors a median of 12 years (range 2-26 years) after diagnosis. The addition of rituximab to chemotherapy with BBBD for PCNSL can be safely accomplished with excellent overall survival. Our translational studies of thiol agents to protect against platinum-induced toxicities led to the development of a two-compartment model in brain tumor patients. We showed that delayed high-dose sodium thiosulfate protects against carboplatin-induced hearing loss, providing the framework for large cooperative group trials of hearing chemoprotection. Neuroimaging studies have identified that ferumoxytol, an iron oxide nanoparticle blood pool agent, appears to be a superior contrast agent to accurately assess therapy-induced changes in brain tumor vasculature, in brain tumor response to therapy, and in differentiating central nervous system lesions with inflammatory components. This chapter reviews the breakthroughs, challenges, and future directions for BBBD. © 2014 Elsevier Inc. All rights reserved.

  9. Delivery of Chemotherapeutics Across the Blood–Brain Barrier: Challenges and Advances

    Science.gov (United States)

    Doolittle, Nancy D.; Muldoon, Leslie L.; Culp, Aliana Y.; Neuwelt, Edward A.

    2017-01-01

    The blood–brain barrier (BBB) limits drug delivery to brain tumors. We utilize intraarterial infusion of hyperosmotic mannitol to reversibly open the BBB by shrinking endothelial cells and opening tight junctions between the cells. This approach transiently increases the delivery of chemotherapy, antibodies, and nanoparticles to brain. Our preclinical studies have optimized the BBB disruption (BBBD) technique and clinical studies have shown its safety and efficacy. The delivery of methotrexate-based chemotherapy in conjunction with BBBD provides excellent outcomes in primary central nervous system lymphoma (PCNSL) including stable or improved cognitive function in survivors a median of 12 years (range 2–26 years) after diagnosis. The addition of rituximab to chemotherapy with BBBD for PCNSL can be safely accomplished with excellent overall survival. Our translational studies of thiol agents to protect against platinum-induced toxicities led to the development of a two-compartment model in brain tumor patients. We showed that delayed high-dose sodium thiosulfate protects against carboplatin-induced hearing loss, providing the framework for large cooperative group trials of hearing chemoprotection. Neuroimaging studies have identified that ferumoxytol, an iron oxide nanoparticle blood pool agent, appears to be a superior contrast agent to accurately assess therapy-induced changes in brain tumor vasculature, in brain tumor response to therapy, and in differentiating central nervous system lesions with inflammatory components. This chapter reviews the breakthroughs, challenges, and future directions for BBBD. PMID:25307218

  10. Financial Technology: The Promise of Blockchain

    OpenAIRE

    Demary, Markus; Demary, Vera

    2017-01-01

    Digitization affects all sectors of the economy. A new and possibly disruptive digital technology is the blockchain, a decentralized ledger, which seems to offer great promise for many financial and business applications.

  11. 9th KES Conference on Agent and Multi-Agent Systems : Technologies and Applications

    CERN Document Server

    Howlett, Robert; Jain, Lakhmi

    2015-01-01

    Agents and multi-agent systems are related to a modern software paradigm which has long been recognized as a promising technology for constructing autonomous, complex and intelligent systems. The topics covered in this volume include agent-oriented software engineering, agent co-operation, co-ordination, negotiation, organization and communication, distributed problem solving, specification of agent communication languages, agent privacy, safety and security, formalization of ontologies and conversational agents. The volume highlights new trends and challenges in agent and multi-agent research and includes 38 papers classified in the following specific topics: learning paradigms, agent-based modeling and simulation, business model innovation and disruptive technologies, anthropic-oriented computing, serious games and business intelligence, design and implementation of intelligent agents and multi-agent systems, digital economy, and advances in networked virtual enterprises. Published p...

  12. The chemotherapeutic potential of glycol alkyl ethers: structure-activity studies of nine compounds in a Fischer-rat leukemia transplant model.

    Science.gov (United States)

    Dieter, M P; Jameson, C W; Maronpot, R R; Langenbach, R; Braun, A G

    1990-01-01

    further development as chemotherapeutic agents.

  13. [Experimental study of the relationships between activation of erythropoiesis and hematotoxicity of some antitumoral agents (author's transl)].

    Science.gov (United States)

    Pannacciulli, I; Bogliolo, G; Massa, G; Ronco, D; Fresco, G; Saviane, A; Dolcino, G; Celle, G

    1975-01-01

    The changes in the blood toxicity of some antitumoral chemotherapeutic agents in the presence of erythropoiesis activation by bleeding are evaluated. The general toxicity seems to be unaffected but the damage to erythropoiesis proved, in absolute terms, to be more severe in the bled animals. The recovery of hematopoiesis was slower after some drug than others. These results are discussed in the light of present knowledge of hematopoietic kinetics and of the relationships between antiblastic drugs and staminal hematopoietic compartments.

  14. Interacting agents in finance

    NARCIS (Netherlands)

    Hommes, C.; Durlauf, S.N.; Blume, L.E.

    2008-01-01

    Interacting agents in finance represent a behavioural, agent-based approach in which financial markets are viewed as complex adaptive systems consisting of many boundedly rational agents interacting through simple heterogeneous investment strategies, constantly adapting their behaviour in response

  15. Riot Control Agents

    Science.gov (United States)

    ... Submit What's this? Submit Button Facts About Riot Control Agents Interim document Recommend on Facebook Tweet Share Compartir What riot control agents are Riot control agents (sometimes referred to ...

  16. The ROS/SUMO Axis Contributes to the Response of Acute Myeloid Leukemia Cells to Chemotherapeutic Drugs

    Directory of Open Access Journals (Sweden)

    Guillaume Bossis

    2014-06-01

    Full Text Available Chemotherapeutic drugs used in the treatment of acute myeloid leukemias (AMLs are thought to induce cancer cell death through the generation of DNA double-strand breaks. Here, we report that one of their early effects is the loss of conjugation of the ubiquitin-like protein SUMO from its targets via reactive oxygen species (ROS-dependent inhibition of the SUMO-conjugating enzymes. Desumoylation regulates the expression of specific genes, such as the proapoptotic gene DDIT3, and helps induce apoptosis in chemosensitive AMLs. In contrast, chemotherapeutics do not activate the ROS/SUMO axis in chemoresistant cells. However, pro-oxidants or inhibition of the SUMO pathway by anacardic acid restores DDIT3 expression and apoptosis in chemoresistant cell lines and patient samples, including leukemic stem cells. Finally, inhibition of the SUMO pathway decreases tumor growth in mice xenografted with AML cells. Thus, targeting the ROS/SUMO axis might constitute a therapeutic strategy for AML patients resistant to conventional chemotherapies.

  17. Decreased expression of microRNA let-7i and its association with chemotherapeutic response in human gastric cancer

    Directory of Open Access Journals (Sweden)

    Liu Kun

    2012-10-01

    Full Text Available Abstract Background MicroRNA let-7i has been proven to be down-regulated in many human malignancies and correlated with tumor progression and anticancer drug resistance. Our study aims to characterize the contribution of miRNA let-7i to the initiation and malignant progression of locally advanced gastric cancer (LAGC, and evaluate its possible value in neoadjuvant chemotherapeutic efficacy prediction. Methods Eighty-six previously untreated LAGC patients who underwent preoperative chemotherapy and radical resection were included in our study. Let-7i expression was examined for pairs of cancer tissues and corresponding normal adjacent tissues (NATs, using quantitative RT-PCR. The relationship of let-7i level to clinicopathological characteristics, pathologic tumor regression grades after chemotherapy, and overall survival (OS was also investigated. Results Let-7i was significantly down-regulated in most tumor tissues (78/86: 91% compared with paired NATs (P P =0.024 independently of other clinicopathological factors, including tumor node metastasis (TNM stage (HR = 3.226, P = 0.013, depth of infiltration (HR = 4.167, P P = 0.037. Conclusions These findings indicate that let-7i may be a good candidate for use a therapeutic target and a potential tissue marker for the prediction of chemotherapeutic sensitivity and prognosis in LAGC patients.

  18. Semiotics, Multi-Agent Systems and Organizations

    NARCIS (Netherlands)

    Gazendam, H.W.M.; Jorna, René J.

    1998-01-01

    Multi-agent systems are promising as models of organization because they are based on the idea that most work in human organizations is done based on intelligence, communication, cooperation, and massive parallel processing. They offer an alternative for system theories of organization, which are

  19. Injectable agents affecting subcutaneous fats.

    Science.gov (United States)

    Chen, David Lk; Cohen, Joel L; Green, Jeremy B

    2015-09-01

    Mesotherapy is an intradermal or subcutaneous injection of therapeutic agents to induce local effects, and was pioneered in Europe during the 1950s. For the past 2 decades, there has been significant interest in the use of mesotherapy for minimally invasive local fat contouring. Based on the theorized lipolytic effects of the agent phosphatidylcholine, initial attempts involved its injection into subcutaneous tissue. With further studies, however, it became apparent that the activity attributed to phosphatidylcholine mesotherapy was due to the adipolytic effects of deoxycholate, a detergent used to solubilize phosphatidylcholine. Since then, clinical trials have surfaced that demonstrate the efficacy of a proprietary formulation of deoxycholate for local fat contouring. Current trials on mesotherapy with salmeterol, a b-adrenergic agonist and lipolysis stimulator, are underway-with promising preliminary results as well. ©2015 Frontline Medical Communications.

  20. Interpretation of interspecies differences in the biodistribution of radioactive agents

    International Nuclear Information System (INIS)

    McAfee, J.G.; Subramanian, G.

    1981-01-01

    The biodistribution of some radioactive agents is anomalous and unpredictable from one species to another. However, many agents follow a general pattern of rapid clearance from the blood and total body in small rodents, intermediate clearance in the dog and monkey and slower clearance in man. A major determinant of this interspecies difference is the shorter mean circulation time (blood volume/cardiac output) in smaller animals. To permit comparisons between mammals of varying size, many physiological and metabolic parameters, and stable drug effects have been expressed as power functions with exponents less than 1 (rather than linear functions) of body weight W, or body surface area. Frequency functions such as heart and respiratory rates have been correlated with negative power functions of body weight. The plasma clearances of chemotherapeutic agents in different species has been successfully normalized by altering the time dimension according to power functions of body weight. A similar procedure has been explored to normalize blood and total body clearances of various diagnostic radioactive agents in animals and man. Time equivalent units were derived from W 33 animal / W 33 man. The method failed, however for agents with a predominantly intracellular localization or undergoing active cellular transport (such as T1-201 or I-131 Hippuran). Nonetheless, this approach appears useful in distinguishing interspecies variability merely due to body size from interspecies metabolic variations

  1. An HTS-compatible 3D colony formation assay to identify tumor-specific chemotherapeutics.

    Science.gov (United States)

    Horman, Shane R; To, Jeremy; Orth, Anthony P

    2013-12-01

    There has been increasing interest in the development of cellular behavior models that take advantage of three-dimensional (3D) cell culture. To enable assessment of differential perturbagen impacts on cell growth in 2D and 3D, we have miniaturized and adapted for high-throughput screening (HTS) the soft agar colony formation assay, employing a laser-scanning cytometer to image and quantify multiple cell types simultaneously. The assay is HTS compatible, providing high-quality, image-based, replicable data for multiple, co-cultured cell types. As proof of concept, we subjected colorectal carcinoma colonies in 3D soft agar to a mini screen of 1528 natural product compounds. Hit compounds from the primary screen were rescreened in an HTS 3D co-culture matrix containing colon stromal cells and cancer cells. By combining tumor cells and normal, nontransformed colon epithelial cells in one primary screening assay, we were able to obtain differential IC50 data, thereby distinguishing tumor-specific compounds from general cytotoxic compounds. Moreover, we were able to identify compounds that antagonized tumor colony formation in 3D only, highlighting the importance of this assay in identifying agents that interfere with 3D tumor structural growth. This screening platform provides a fast, simple, and robust method for identification of tumor-specific agents in a biologically relevant microenvironment.

  2. Do promises matter? An exploration of the role of promises in psychological contract breach.

    Science.gov (United States)

    Montes, Samantha D; Zweig, David

    2009-09-01

    Promises are positioned centrally in the study of psychological contract breach and are argued to distinguish psychological contracts from related constructs, such as employee expectations. However, because the effects of promises and delivered inducements are confounded in most research, the role of promises in perceptions of, and reactions to, breach remains unclear. If promises are not an important determinant of employee perceptions, emotions, and behavioral intentions, this would suggest that the psychological contract breach construct might lack utility. To assess the unique role of promises, the authors manipulated promises and delivered inducements separately in hypothetical scenarios in Studies 1 (558 undergraduates) and 2 (441 employees), and they measured them separately (longitudinally) in Study 3 (383 employees). The authors' results indicate that breach perceptions do not represent a discrepancy between what employees believe they were promised and were given. In fact, breach perceptions can exist in the absence of promises. Further, promises play a negligible role in predicting feelings of violation and behavioral intentions. Contrary to the extant literature, the authors' findings suggest that promises may matter little; employees are concerned primarily with what the organization delivers.

  3. Balancing repair and tolerance of DNA damage caused by alkylating agents.

    Science.gov (United States)

    Fu, Dragony; Calvo, Jennifer A; Samson, Leona D

    2012-01-12

    Alkylating agents constitute a major class of frontline chemotherapeutic drugs that inflict cytotoxic DNA damage as their main mode of action, in addition to collateral mutagenic damage. Numerous cellular pathways, including direct DNA damage reversal, base excision repair (BER) and mismatch repair (MMR), respond to alkylation damage to defend against alkylation-induced cell death or mutation. However, maintaining a proper balance of activity both within and between these pathways is crucial for a favourable response of an organism to alkylating agents. Furthermore, the response of an individual to alkylating agents can vary considerably from tissue to tissue and from person to person, pointing to genetic and epigenetic mechanisms that modulate alkylating agent toxicity.

  4. The path to fulfilling the promise

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, J. [Canadian Nuclear Association, Ottawa, ON (Canada)

    2014-07-01

    'Full text:'Countries work together to develop effective governance and regulation. Canada has made big investments in these areas and it carries a premium for us. The rapid build-out of nuclear technology around the Pacific Rim holds vast promise for our populations in better climate, better air, affordable and reliable electricity, and longer lives. The biggest risk is not another accident: rather, it is the risk of failing to fulfill that promise to our people. Every country that wants the benefits of nuclear must also want to be sure that those benefits are realized and sustained by good governance and regulation. Canada has the people, laws, organizations, public institutions, and relationships that can help our partners fulfill the whole and lasting promise of nuclear technology. (author)

  5. Promising Compilation to ARMv8 POP

    OpenAIRE

    Podkopaev, Anton; Lahav, Ori; Vafeiadis, Viktor

    2017-01-01

    We prove the correctness of compilation of relaxed memory accesses and release-acquire fences from the "promising" semantics of [Kang et al. POPL'17] to the ARMv8 POP machine of [Flur et al. POPL'16]. The proof is highly non-trivial because both the ARMv8 POP and the promising semantics provide some extremely weak consistency guarantees for normal memory accesses; however, they do so in rather different ways. Our proof of compilation correctness to ARMv8 POP strengthens the results of the Kan...

  6. Reasoning about emotional agents

    OpenAIRE

    Meyer, J.-J.

    2004-01-01

    In this paper we discuss the role of emotions in artificial agent design, and the use of logic in reasoning about the emotional or affective states an agent can reside in. We do so by extending the KARO framework for reasoning about rational agents appropriately. In particular we formalize in this framework how emotions are related to the action monitoring capabilities of an agent.

  7. Nanomedicine: Perspective and promises with ligand-directed molecular imaging

    Energy Technology Data Exchange (ETDEWEB)

    Pan Dipanjan [Department of Medicine, Washington University Medical School, St. Louis, MO (United States)], E-mail: dipanjan@wustl.edu; Lanza, Gregory M.; Wickline, Samuel A. [Department of Medicine, Washington University Medical School, St. Louis, MO (United States); Caruthers, Shelton D. [Department of Medicine, Washington University Medical School, St. Louis, MO (United States); Philips Healthcare, Andover, MA (United States)], E-mail: scaruthers@cmrl.wustl.edu

    2009-05-15

    Molecular imaging and targeted drug delivery play an important role toward personalized medicine, which is the future of patient management. Of late, nanoparticle-based molecular imaging has emerged as an interdisciplinary area, which shows promises to understand the components, processes, dynamics and therapies of a disease at a molecular level. The unprecedented potential of nanoplatforms for early detection, diagnosis and personalized treatment of diseases, have found application in every biomedical imaging modality. Biological and biophysical barriers are overcome by the integration of targeting ligands, imaging agents and therapeutics into the nanoplatform which allow for theranostic applications. In this article, we have discussed the opportunities and potential of targeted molecular imaging with various modalities putting a particular emphasis on perfluorocarbon nanoemulsion-based platform technology.

  8. Nanomedicine: Perspective and promises with ligand-directed molecular imaging

    International Nuclear Information System (INIS)

    Pan Dipanjan; Lanza, Gregory M.; Wickline, Samuel A.; Caruthers, Shelton D.

    2009-01-01

    Molecular imaging and targeted drug delivery play an important role toward personalized medicine, which is the future of patient management. Of late, nanoparticle-based molecular imaging has emerged as an interdisciplinary area, which shows promises to understand the components, processes, dynamics and therapies of a disease at a molecular level. The unprecedented potential of nanoplatforms for early detection, diagnosis and personalized treatment of diseases, have found application in every biomedical imaging modality. Biological and biophysical barriers are overcome by the integration of targeting ligands, imaging agents and therapeutics into the nanoplatform which allow for theranostic applications. In this article, we have discussed the opportunities and potential of targeted molecular imaging with various modalities putting a particular emphasis on perfluorocarbon nanoemulsion-based platform technology.

  9. Persistence of DNA adducts, hypermutation and acquisition of cellular resistance to alkylating agents in glioblastoma.

    Science.gov (United States)

    Head, R J; Fay, M F; Cosgrove, L; Y C Fung, K; Rundle-Thiele, D; Martin, J H

    2017-12-02

    Glioblastoma is a lethal form of brain tumour usually treated by surgical resection followed by radiotherapy and an alkylating chemotherapeutic agent. Key to the success of this multimodal approach is maintaining apoptotic sensitivity of tumour cells to the alkylating agent. This initial treatment likely establishes conditions contributing to development of drug resistance as alkylating agents form the O 6 -methylguanine adduct. This activates the mismatch repair (MMR) process inducing apoptosis and mutagenesis. This review describes key juxtaposed drivers in the balance between alkylation induced mutagenesis and apoptosis. Mutations in MMR genes are the probable drivers for alkylation based drug resistance. Critical to this interaction are the dose-response and temporal interactions between adduct formation and MMR mutations. The precision in dose interval, dose-responses and temporal relationships dictate a role for alkylating agents in either promoting experimental tumour formation or inducing tumour cell death with chemotherapy. Importantly, this resultant loss of chemotherapeutic selective pressure provides opportunity to explore novel therapeutics and appropriate combinations to minimise alkylation based drug resistance and tumour relapse.

  10. Olesoxime (cholest-4-en-3-one, oxime): Analgesic and neuroprotective effects in a rat model of painful peripheral neuropathy produced by the chemotherapeutic agent, paclitaxel

    OpenAIRE

    Xiao, Wen Hua; Zheng, Felix Y.; Bennett, Gary J.; Bordet, Thierry; Pruss, Rebecca M.

    2009-01-01

    Olesoxime is a small cholesterol-like molecule that was discovered in a screening program aimed at finding treatment for amyotrophic lateral sclerosis and other diseases where motor neurons degenerate. In addition to its neuroprotective and pro-regenerative effects on motor neurons in vitro and in vivo, it has been shown to have analgesic effects in rat models of painful peripheral neuropathy due to vincristine and diabetes. We used a rat model of painful peripheral neuropathy produced by the...

  11. Smac mimetic-derived augmentation of chemotherapeutic response in experimental pancreatic cancer

    Directory of Open Access Journals (Sweden)

    Schwarz Margaret A

    2011-01-01

    Full Text Available Abstract Background Pancreatic ductal adenocarcinoma (PDAC is highly resistant to conventional chemotherapy, in part due to the overexpression of inhibitors of apoptosis proteins (IAPs. Smac is an endogenous IAP-antagonist, which renders synthetic Smac mimetics attractive anticancer agents. We evaluated the benefits of combining a Smac mimetic, JP1201 (JP, with conventional chemotherapy agents used for PDAC management. Methods Cell viability assays and protein expression analysis were performed using WST-1 reagent and Western blotting, respectively. Apoptosis was detected by annexin V/propidium iodide staining. In vivo tumor growth and survival studies were performed in murine PDAC xenografts. Results JP and gemcitabine (Gem inhibited PDAC cell proliferation with additive effects in combination. The percentage of early apoptotic cells in controls, JP, Gem and JP + Gem was 17%, 26%, 26% and 38%, respectively. JP-induced apoptosis was accompanied by PARP-1 cleavage. Similar additive anti-proliferative effects were seen for combinations of JP with doxorubicin (Dox and docetaxel (DT. The JP + Gem combination caused a 30% decrease in tumor size in vivo compared to controls. Median animal survival was improved significantly in mice treated with JP + Gem (38 d compared to controls (22 d, JP (28 d or Gem (32 d (p = 0.01. Animal survival was also improved with JP + DT treatment (32 d compared to controls (16 d, JP (21 d or DT alone (27 d. Conclusions These results warrant further exploration of strategies that promote chemotherapy-induced apoptosis of tumors and highlight the potential of Smac mimetics in clinical PDAC therapy.

  12. The Promise of Zoomable User Interfaces

    Science.gov (United States)

    Bederson, Benjamin B.

    2011-01-01

    Zoomable user interfaces (ZUIs) have received a significant amount of attention in the 18 years since they were introduced. They have enjoyed some success, and elements of ZUIs are widely used in computers today, although the grand vision of a zoomable desktop has not materialised. This paper describes the premise and promise of ZUIs along with…

  13. Promising carbons for supercapacitors derived from fungi

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Hui; Wang, Xiaolei; Yang, Fan; Yang, Xiurong [State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022 (China)

    2011-06-24

    Activated carbons with promising performance in capacitors are produced from fungi via a hydrothermal assistant pyrolysis approach. This study introduces a facile strategy to discover carbonaceous materials and triggers interest in exploring fungi for material science applications. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Seaweed: Promising plant of the millennium

    Digital Repository Service at National Institute of Oceanography (India)

    Dhargalkar, V.K.; Pereira, N.

    Seaweeds, one of the important marine living resources could be termed as the futuristically promising plants. These plants have been a source of food, feed and medicine in the orient as well as in the west, since ancient times. Although, seaweeds...

  15. Complexity of Propositional Proofs Under a Promise

    Czech Academy of Sciences Publication Activity Database

    Dershowitz, N.; Tzameret, Iddo

    2010-01-01

    Roč. 11, č. 3 (2010), s. 1-29 ISSN 1529-3785 Institutional research plan: CEZ:AV0Z10190503 Keywords : theory * promise problems * propositional proof complexity * random 3CNF * resolution Subject RIV: BA - General Mathematics Impact factor: 1.391, year: 2010 http://dl.acm.org/ citation .cfm?doid=1740582.1740586

  16. Complexity of Propositional Proofs Under a Promise

    Czech Academy of Sciences Publication Activity Database

    Dershowitz, N.; Tzameret, Iddo

    2010-01-01

    Roč. 11, č. 3 (2010), s. 1-29 ISSN 1529-3785 Institutional research plan: CEZ:AV0Z10190503 Keywords : theory * promise problems * propositional proof complexity * random 3CNF * resolution Subject RIV: BA - General Mathematics Impact factor: 1.391, year: 2010 http://dl.acm.org/citation.cfm?doid=1740582.1740586

  17. 76 FR 13152 - Promise Neighborhoods Program

    Science.gov (United States)

    2011-03-10

    ... comprehensive education reforms that are linked to improved educational outcomes for children and youth in... parents or family members who report talking with their child about the importance of college and career... DEPARTMENT OF EDUCATION RIN 1855-ZA07 Promise Neighborhoods Program Catalog of Federal Domestic...

  18. Enabling Agility through Coordinating Temporally Constrained Planning Agents

    NARCIS (Netherlands)

    Steenhuisen, J.R.; De Weerdt, M.M.; Witteveen, C.

    2007-01-01

    In crisis response, hierarchical organizations are being replaced by dynamic assemblies of autonomous agents that promise more agility. However, these autonomous agents might cause a decrease in effectiveness when individually constructed plans for moderately-coupled tasks are not jointly feasible.

  19. Autonomous parsing of behavior in a multi-agent setting

    NARCIS (Netherlands)

    Vanderelst, D.; Barakova, E.I.; Rutkowski, L.; Tadeusiewicz, R.

    2008-01-01

    Imitation learning is a promising route to instruct robotic multi-agent systems. However, imitating agents should be able to decide autonomously what behavior, observed in others, is interesting to copy. Here we investigate whether a simple recurrent network (Elman Net) can be used to extract

  20. Contrast agent based on nano-emulsion for targeted biomedical imaging

    International Nuclear Information System (INIS)

    Attia, Mohamed

    2016-01-01

    X-ray imaging agents are essential in combination with X-ray computed tomography to improve contrast enhancement aiming at providing complete visualization of blood vessels and giving structural and functional information on lesions allowing the detection of a tumor. As well as it is fundamental tool to discriminate between healthy cells and pathogens. We successfully limit the problems presented in commercial X-ray contrast agents like poor contrasting in Fenestra VC associated with short blood circulation time and to avoid rapid renal elimination from the body as found in Xenetix (Iobitriol). We developed nontoxic and blood pool iodine-containing nano-emulsion contrast agents serving in preclinical X-ray μ-CT imaging such as, a- Tocopherol (vitamin E), Cholecalciferol (vitamin D3), Castor oil, Capmul MCMC8 oil and oleic acid. Those formulated nano emulsions were prepared by low energy spontaneous emulsification technic with slight modification for each platform. They showed new specific features rendering them promising agents in in vivo experiments as improving the balance between the efficacy and the toxicity of targeted therapeutic interventions. We investigate the effect of size and the chemical composition of the nanoparticles on their biodistribution, pharmacokinetics and toxicity. They demonstrated that the chemical structures of the droplet's cores have significant role in targeting for example vitamin E was mainly accumulated in liver and castor oil formulation was passively accumulated in spleen explaining the proof-of-concept of EPR effect. On the other hand, two different platform sizes of Cholecalciferol molecule revealing that no real impact on the pharmacokinetics and biodistribution but presented remarkable effect on the toxicity. Of particular interest is studying the effect of the surface charge of nanoparticles on their biodistribution, this is why oleic acid nano-emulsion was selected to proceed this study by presence of amphiphilic polymer

  1. Gold nanorods as molecular contrast agents in photoacoustic imaging: the promises and the caveats

    NARCIS (Netherlands)

    Manohar, Srirang; Ungureanu, C.; van Leeuwen, Ton

    2011-01-01

    Rod-shaped gold nanoparticles exhibit intense and narrow absorption peaks for light in the far-red and near-infrared wavelength regions, owing to the excitation of longitudinal plasmons. Light absorption is followed predominantly by non radiative de-excitation, and the released heat and subsequent

  2. New promising antifouling agent based on polymeric biocide polyhexamethylene guanidine molybdate.

    Science.gov (United States)

    Protasov, Alexander; Bardeau, Jean-Francois; Morozovskaya, Irina; Boretska, Mariia; Cherniavska, Tetiana; Petrus, Lyudmyla; Tarasyuk, Oksana; Metelytsia, Larisa; Kopernyk, Iryna; Kalashnikova, Larisa; Dzhuzha, Oleg; Rogalsky, Sergiy

    2017-09-01

    A new polymeric biocide polyhexamethylene guanidine (PHMG) molybdate has been synthesized. The obtained cationic polymer has limited water solubility of 0.015 g/100 mL and is insoluble in paint solvents. The results of acute toxicity studies indicate moderate toxicity of PHMG molybdate, which has a median lethal dose at 48 h of 0.7 mg/L for Daphnia magna and at 96 h of 17 mg/L for Danio rerio (zebrafish) freshwater model organisms. Commercial ship paint was then modified by the addition of a low concentration of polymeric biocide 5% (w/w). The painted steel panels were kept in Dnipro River water for the evaluation of the dynamics of fouling biomass. After 129-d exposure, Bryozoa dominated in biofouling of tested substrates, forming 86% (649 g/m 2 ) of the total biomass on control panel surfaces. However, considerably lower Bryozoa fouling biomass (15 g/m 2 ) was detected for coatings containing PHMG molybdate. Dreissenidae mollusks were found to form 88% (2182 g/m 2 ) of the fouling biomass on the control substrates after 228 d of exposure, whereas coatings containing PHMG molybdate showed a much lower biomass value of 23.6 g/m 2 . The leaching rate of PHMG molybdate in water was found to be similar to rates for conventional booster biocides ranging from 5.7 μg/cm 2 /d at the initial stage to 2.2 μg/cm 2 /d at steady state. Environ Toxicol Chem 2017;36:2543-2551. © 2017 SETAC. © 2017 SETAC.

  3. Curcumin as a clinically-promising anti-cancer agent: pharmacokinetics and drug interactions.

    Science.gov (United States)

    Adiwidjaja, Jeffry; McLachlan, Andrew J; Boddy, Alan V

    2017-09-01

    Curcumin has been extensively studied for its anti-cancer properties. While a diverse array of in vitro and preclinical research support the prospect of curcumin use as an anti-cancer therapeutic, most human studies have failed to meet the intended clinical expectation. Poor systemic availability of orally-administered curcumin may account for this disparity. Areas covered: This descriptive review aims to concisely summarise available clinical studies investigating curcumin pharmacokinetics when administered in different formulations. A critical analysis of pharmacokinetic- and pharmacodynamic-based interactions of curcumin with concomitantly administered drugs is also provided. Expert opinion: The encouraging clinical results of curcumin administration are currently limited to people with colorectal cancer, given that sufficient curcumin concentrations persist in colonic mucosa. Higher parent curcumin systemic exposure, which can be achieved by several newer formulations, has important implications for optimal treatment of cancers other than those in gastrointestinal tract. Curcumin-drug pharmacokinetic interactions are also almost exclusively in the enterocytes, owing to extensive first pass metabolism and poor curcumin bioavailability. Greater scope of these interactions, i.e. modulation of the systemic elimination of co-administered drugs, may be expected from more-bioavailable curcumin formulations. Further studies are still warranted, especially with newer formulations to support the inclusion of curcumin in cancer therapy regimens.

  4. Aqueous citric acid as a promising cleaning agent of whey evaporators

    DEFF Research Database (Denmark)

    Hedegaard, Martina Vavrusova; P. Johansen, Nikolaj; Garcia, André Castilho

    2017-01-01

    concentration of citric acid was the most effective for all the investigated volumes. From the citric acid solutions, spontaneously supersaturated in calcium citrate tetrahydrate during scale dissolution in the smaller volumes for all citric acid concentrations, calcium citrate tetrahydrate slowly precipitated...... in acceptable purity for technical use. Dissolution efficiency of aqueous solutions of 0.200 mol L−1 nitric acid combined with 0.100, 0.500, and 1.00 mol L−1 citric acid with final volumes of 100, 50, and 25 mL showed synergistic effect especially for the higher concentrations and lower volumes of two acids...

  5. Plant latex: a promising antifungal agent for post harvest disease control.

    Science.gov (United States)

    Sibi, G; Wadhavan, Rashmi; Singh, Sneha; Shukla, Abhilasha; Dhananjaya, K; Ravikumar, K R; Mallesha, H

    2013-12-01

    Bioactive compounds from plant latex are potential source of antifungic against post harvest pathogens. Latex from a total of seven plant species was investigated for its phytochemical and antifungal properties. Six fungi namely Aspergillus fumigatus, A. niger, A. terreus, F. solani, P. digitatum and R. arrhizus were isolated from infected fruits and vegetables and tested against various solvent extracts of latex. Analysis of latex extracts with phytochemical tests showed the presence of alkaloids, flavonoids, glycosides, phenols, saponins, steroids, tannins and terpenoids. Antifungal assay revealed the potential inhibitory activity of petroleum ether extracts against the postharvest fungal isolates. Various degree of sensitivity was observed irrespective of plant species studied with A. terreus and P. digitatum as the most susceptible ones. F. solani and A. fumigatus were moderately sensitive to the latex extracts tested. Among the plants, latex of Thevetia peruviana (75.2%) and Artocarpus heterophyllus (64.8%) were having potential antifungal activity against the isolates followed by Manilkara zapota (51.1%). In conclusion, use of plant latex makes interest to control postharvest fungal diseases and is fitting well with the concept of safety for human health and environment.

  6. Can propolis and caffeic acid phenethyl ester (CAPE be promising agents against cyclophosphamide toxicity?

    Directory of Open Access Journals (Sweden)

    Sumeyya Akyol

    2016-03-01

    Full Text Available Propolis is a mixture having hundreds of polyphenols including caffeic acid phenethyl ester (CAPE. They have been using in several medical conditions/diseases in both in vitro and in vivo experimental setup. Cyclophosphamide has been used to treat a broad of malignancies including Hodgkin’s and non-Hodgking’s lymphoma, Burkitt’s lymphoma, chronic lymphocytic leukemia, Ewing’s sarcoma, breast cancer, testicular cancer, etc. It may cause several side effects after treatment. In this mini review, the protective effects of propolis and CAPE were compared each other in terms of effectiveness against cyclophosphamide-induced injuries. [J Complement Med Res 2016; 5(1.000: 105-107

  7. Lansoprazole-sulfide, pharmacokinetics of this promising anti-tuberculous agent.

    Science.gov (United States)

    Mdanda, Sipho; Baijnath, Sooraj; Shobo, Adeola; Singh, Sanil D; Maguire, Glenn E M; Kruger, Hendrik G; Arvidsson, Per I; Naicker, Tricia; Govender, Thavendran

    2017-12-01

    Lansoprazole (LPZ) is a commercially available proton-pump inhibitor whose primary metabolite, lansoprazole sulfide (LPZS) was recently reported to have in vitro and in vivo activity against Mycobacterium tuberculosis. It was also reported that a 300 mg kg -1 oral administration of LPZS was necessary to reach therapeutic levels in the lung, with the equivalent human dose being unrealistic. A validated liquid chromatography-tandem mass spectrometric method (LC-MS/MS) for the simultaneous quantification LPZ and LPZS in rat plasma and lung homogenates was developed. We administered 15 mg kg -1 oral doses of LPZ to a healthy rat model to determine the pharmacokinetics of its active metabolite, LPZS, in plasma and lung tissue. We found that the LPZS was present in amounts that were below the limit of quantification. This prompted us to administer the same dose of LPZS to the experimental animals intraperitoneally (i.p.). Using this approach, we found high concentrations of LPZS in plasma and lung, 7841.1 and 9761.2 ng mL -1 , respectively, which were significantly greater than the minimum inhibitory concentration (MIC) for Mycobacterium tuberculosis. While oral and i.p. administration of LPZ resulted in significant concentrations in the lung, it did not undergo sufficient cellular conversion to its anti-TB metabolite. However, when LPZS itself was administered i.p., significant amounts penetrated the tissue. These results have implications for future in vivo studies exploring the potential of LPZS as an anti-TB compound. Copyright © 2017 John Wiley & Sons, Ltd.

  8. Lignin-coated cellulose nanocrystals as promising nucleating agent for poly(lactic acid)

    Science.gov (United States)

    Anju Gupta; William Simmons; Gregory T. Schueneman; Eric A. Mintz

    2016-01-01

    We report the effect of lignin-coated cellulose nanocrystals (L-CNCs) on the crystallization behavior of poly(lactic acid) (PLA). PLA/L-CNC nanocomposites were prepared by melt mixing, and the crystallization behavior of PLA was investigated using differential scanning calorimetry. Isothermal crystallization data were analyzed using Avrami and Lauritzen–Hoffman...

  9. Dual orexin receptor antagonists - promising agents in the treatment of sleep disorders.

    Science.gov (United States)

    Pałasz, Artur; Lapray, Damien; Peyron, Christelle; Rojczyk-Gołębiewska, Ewa; Skowronek, Rafał; Markowski, Grzegorz; Czajkowska, Beata; Krzystanek, Marek; Wiaderkiewicz, Ryszard

    2014-01-01

    Insomnia is a serious medical and social problem, its prevalence in the general population ranges from 9 to 35% depending on the country and assessment method. Often, patients are subject to inappropriate and therefore dangerous pharmacotherapies that include prolonged administration of hypnotic drugs, benzodiazepines and other GABAA receptor modulators. This usually does not lead to a satisfactory improvement in patients' clinical states and may cause lifelong drug dependence. Brain state transitions require the coordinated activity of numerous neuronal pathways and brain structures. It is thought that orexin-expressing neurons play a crucial role in this process. Due to their interaction with the sleep-wake-regulating neuronal population, they can activate vigilance-promoting regions and prevent unwanted sleep intrusions. Understanding the multiple orexin modulatory effects is crucial in the context of pathogenesis of insomnia and should lead to the development of novel treatments. An important step in this process was the synthesis of dual antagonists of orexin receptors. Crucially, these drugs, as opposed to benzodiazepines, do not change the sleep architecture and have limited side-effects. This new pharmacological approach might be the most appropriate to treat insomnia.

  10. Acetaldoxime - a promising reducing agent for Pu and Np ions in the Purex process

    International Nuclear Information System (INIS)

    Koltunov, V.S.; Baranov, S.M.; Mezhov, E.A.; Pastuschak, V.G.; Koltunov, G.V.; Taylor, R.J.

    2000-01-01

    This paper discusses the properties of acetaldoxime as an example of a novel class of salt-free organic reductants for Np and Pu ions, the monoximes. The products of its reactions with Np(VI) and Pu(IV) are Np(V), Pu(III), N 2 O, CH 3 CHO and CH 3 COOH. The rate of the Np(VI) - CH 3 CHNOH reaction is first order relative to both reagents and negative first order relative to HNO 3 . The rate constant is k 1 = 254 ± 10 min -1 at 26 deg. C and the activation energy is E = 62.6 ± 2.6 kJ/mol. The orders of the Pu(IV) - CH 3 CHNOH reaction for Pu(IV), Pu(III), CH 3 CHNOH and HNO 3 are equal to 2, -1, 1.1 and -2.2, respectively, and the rate constant is k 2 25.3 ± 1.9 M 1.1 min -1 at 19.5 deg. C. The activation energy is 87.7 ± 2.8 kJ/mol. The likely mechanisms of these reactions are reviewed. Acetaldoxime is stable in HNO 3 solutions when [HNO 3 ] 3 ] = 3.8 - 3.9 M at 35.5 deg. C) a rapid process of HNO 2 formation and acetaldoxime oxidation occurs. Investigations were implemented to study the kinetics of the acetaldoxime oxidation with HNO 2 when [HNO 3 ] 3 under 'critical' conditions. (authors)

  11. Carboxymethylated chitosan-stabilized copper nanoparticles: a promise to contribute a potent antifungal and antibacterial agent

    Energy Technology Data Exchange (ETDEWEB)

    Tantubay, Sangeeta, E-mail: sang.chem2@gmail.com [Indian Institute of Technology Kharagpur, Department of Chemistry (India); Mukhopadhyay, Sourav K. [Indian Institute of Technology Kharagpur, Department of Biotechnology (India); Kalita, Himani; Konar, Suraj [Indian Institute of Technology Kharagpur, Department of Chemistry (India); Dey, Satyahari [Indian Institute of Technology Kharagpur, Department of Biotechnology (India); Pathak, Amita, E-mail: ami@chem.iitkgp.ernet.in; Pramanik, Panchanan, E-mail: ppramanik1946@yahoo.in, E-mail: pramanik1946@gmail.com [Indian Institute of Technology Kharagpur, Department of Chemistry (India)

    2015-06-15

    Carboxymethylated chitosan (CMC)-stabilized copper nanoparticles (Cu-NPs) have been synthesized via chemical reduction of copper(II)–CMC complex in aqueous medium by hydrazine under microwave irradiation in ambient atmosphere. Structural morphology, phase, and chemical compositions of CMC-stabilized Cu-NPs (CMC–Cu-NPs) have been analyzed through high-resolution transmission electron microscopy, field emission scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Antifungal and antibacterial activities of CMC–Cu-NPs have been evaluated against Candida tropicalis and Escherichia coli through agar well diffusion method, broth microdilution assay, live–dead assay, and microscopic observation. Antimicrobial activity of spherical CMC–Cu-NPs (∼4–15 nm of diameters) has been observed to be significant for both C. tropicalis and E. coli. The cytotoxicity study indicates that CMC–Cu-NPs have no significant toxic effect against normal cell line, L929.

  12. Fisetin as a promising antifungal agent against Cryptocococcus neoformans species complex.

    Science.gov (United States)

    Reis, M P C; Carvalho, C R C; Andrade, F A; Fernandes, O F L; Arruda, W; Silva, M R R

    2016-08-01

    The aim of this study was to investigate the mechanisms of action of fisetin, a flavonol with antifungal activity previously evaluated against the Cryptococcus neoformans species complex. Ergosterol content and flow cytometry analysis were determined for the C. neoformans species complex in the presence of fisetin and ultrastructural analysis of morphology was performed on Cryptococcus gattii and C. neoformans. Decrease in the total cellular ergosterol content after exposure to fisetin ranged from 25·4% after exposure to 128 μg ml(-1) to 21·6% after exposure to 64 μg ml(-1) of fisetin compared with the control (without fisetin). The fisetin effects obtained with flow cytometry showed metabolic impairment, and alterations in its normal morphology caused by fisetin in C. neoformans cells were verified using scanning electron microscopy. Fisetin is a compound that acts in the biosynthesis of ergosterol. Flow cytometry showed that fisetin reduced viability of the metabolically active cells of C. gattii, while morphological changes explain the action of fisetin in inhibiting growth of these fungi. This study supports the idea that fisetin may represent a good starting point for the development of future therapeutic substances for cryptococcosis. © 2016 The Society for Applied Microbiology.

  13. Neurosteroids and Ischemic Stroke: Progesterone a Promising Agent in Reducing the Brain Injury in Ischemic Stroke.

    Science.gov (United States)

    Andrabi, Syed Suhail; Parvez, Suhel; Tabassum, Heena

    2017-01-01

    Progesterone (P4), a well-known neurosteroid, is produced by ovaries and placenta in females and by adrenal glands in both sexes. Progesterone is also synthesized by central nervous system (CNS) tissues to perform various vital neurological functions in the brain. Apart from performing crucial reproductive functions, it also plays a pivotal role in neurogenesis, regeneration, cognition, mood, inflammation, and myelination in the CNS. A substantial body of experimental evidence from animal models documents the neuroprotective role of P4 in various CNS injury models, including ischemic stroke. Extensive data have revealed that P4 elicits neuroprotection through multiple mechanisms and systems in an integrated manner to prevent neuronal and glial damage, thus reducing mortality and morbidity. Progesterone has been described as safe for use at the clinical level through different routes in several studies. Data regarding the neuroprotective role of P4 in ischemic stroke are of great interest due to their potential clinical implications. In this review, we succinctly discuss the biosynthesis of P4 and distribution of P4 receptors (PRs) in the brain. We summarize our work on the general mechanisms of P4 mediated via the modulation of different PR and neurotransmitters. Finally, we describe the neuroprotective mechanisms of P4 in ischemic stroke models and related clinical prospects.

  14. Computational Enzymology and Organophosphorus Degrading Enzymes: Promising Approaches Toward Remediation Technologies of Warfare Agents and Pesticides.

    Science.gov (United States)

    Ramalho, Teodorico C; de Castro, Alexandre A; Silva, Daniela R; Silva, Maria Cristina; Franca, Tanos C C; Bennion, Brian J; Kuca, Kamil

    2016-01-01

    The re-emergence of chemical weapons as a global threat in hands of terrorist groups, together with an increasing number of pesticides intoxications and environmental contaminations worldwide, has called the attention of the scientific community for the need of improvement in the technologies for detoxification of organophosphorus (OP) compounds. A compelling strategy is the use of bioremediation by enzymes that are able to hydrolyze these molecules to harmless chemical species. Several enzymes have been studied and engineered for this purpose. However, their mechanisms of action are not well understood. Theoretical investigations may help elucidate important aspects of these mechanisms and help in the development of more efficient bio-remediators. In this review, we point out the major contributions of computational methodologies applied to enzyme based detoxification of OPs. Furthermore, we highlight the use of PTE, PON, DFP, and BuChE as enzymes used in OP detoxification process and how computational tools such as molecular docking, molecular dynamics simulations and combined quantum mechanical/molecular mechanics have and will continue to contribute to this very important area of research.

  15. Aspirin as a Promising Agent for Decreasing Incidence of Cerebral Aneurysm Rupture

    NARCIS (Netherlands)

    Hasan, David M.; Mahaney, Kelly B.; Brown, Robert D.; Meissner, Irene; Piepgras, David G.; Huston, John; Capuano, Ana W.; Torner, James C.; Groen, R.J.M.

    2011-01-01

    Background and Purpose-Chronic inflammation is postulated as an important phenomenon in intracranial aneurysm wall pathophysiology. This study was conducted to determine if aspirin use impacts the occurrence of intracranial aneurysm rupture. Methods-Subjects enrolled in the International Study of

  16. Carnosol: A promising anti-cancer and anti-inflammatory agent

    OpenAIRE

    Johnson, Jeremy J.

    2011-01-01

    The Mediterranean diet and more specifically certain meats, fruits, vegetables, and olive oil found in certain parts of the Mediterranean region have been associated with a decreased cardiovascular and diabetes risk. More recently, several population based studies have observed with these lifestyle choices have reported an overall reduced risk for several cancers. One study in particular observed an inverse relationship between consumption of Mediterranean herbs such as rosemary, sage, parsle...

  17. Acriflavine enhances the antitumor activity of the chemotherapeutic drug 5-fluorouracil in colorectal cancer cells.

    Science.gov (United States)

    Zargar, Parisa; Ghani, Esmaeel; Mashayekhi, Farideh Jalali; Ramezani, Amin; Eftekhar, Ebrahim

    2018-06-01

    5-Fluorouracil (5-FU)-based chemotherapy improves the overall survival rates of patients with colorectal cancer (CRC). However, only a small proportion of patients respond to 5-FU when used as a single agent. The aim of the present study was to investigate whether the anticancer property of 5-FU is potentiated by combination treatment with acriflavine (ACF) in CRC cells. Additionally, the potential underlying molecular mechanisms of the cytotoxic effect of ACF were determined. The cytotoxic effects of ACF, 5-FU and irinotecan on different CRC cell lines with different p53 status were investigated using an MTT assay. SW480 cells that express a mutated form of p53 and two other CRC cell lines were used, HCT116 and LS174T, with wild-type p53. To determine the effect of ACF on the sensitivity of cells to 5-FU, cells were co-treated with the 30% maximal inhibitory concentration (IC 30 ) of ACF and various concentrations of 5-FU, or pretreated with the IC 30 of ACF and various concentrations of 5-FU. To assess the mechanism of action of ACF, cells were treated with IC 30 values of the compound and then the reverse transcription-quantitative polymerase chain reaction was used to evaluate mRNA levels of hypoxia-inducible factor-1α (HIF-1α) and topoisomerase 2. Results indicate that pretreatment with ACF markedly sensitized CRC cells to the cytotoxic effects of 5-FU, whereas simultaneous treatment with ACF and 5-FU were not able to alter the resistance of CRC cells to 5-FU. In comparison with irinotecan, ACF was a more potent agent for enhancing the antitumor activity of 5-FU. ACF did not alter the mRNA levels of either HIF-1α or topoisomerase 2. The results of the present study reveal for the first time that pretreatment of CRC cells with ACF markedly increases the cytotoxic effects of 5-FU, regardless of the p53 status of cells.

  18. Chemical warfare agents.

    Science.gov (United States)

    Kuca, Kamil; Pohanka, Miroslav

    2010-01-01

    Chemical warfare agents are compounds of different chemical structures. Simple molecules such as chlorine as well as complex structures such as ricin belong to this group. Nerve agents, vesicants, incapacitating agents, blood agents, lung-damaging agents, riot-control agents and several toxins are among chemical warfare agents. Although the use of these compounds is strictly prohibited, the possible misuse by terrorist groups is a reality nowadays. Owing to this fact, knowledge of the basic properties of these substances is of a high importance. This chapter briefly introduces the separate groups of chemical warfare agents together with their members and the potential therapy that should be applied in case someone is intoxicated by these agents.

  19. Service Users perspectives in PROMISE and research.

    Science.gov (United States)

    Rae, Sarah

    2017-09-01

    Since its inception in 2013, PROMISE (PROactive Management of Integrated Services and Environments) has been supporting service users and staff at the Cambridgeshire and Peterborough NHS Foundation Trust (CPFT) on a journey to reduce reliance on force. The author's own personal experiences led to the founding of PROMISE and illustrates how individual experiences can influence a patient to lead change. Coproduction is actively embedded in PROMISE. Patients have been meaningfully involved because they are innovators and problem solvers who bring an alternative viewpoint by the very nature of their condition. A patient is more than just a person who needs to be 'fixed' they are individuals with untapped skills and added insight. There have been 2 separate Patient Advisory Groups (PAGs) since the project was first established. The first Patient Advisory Group was recruited to work with the PROMISE researchers on a study which used a participatory qualitative approach. Drawing on their lived experience and different perspectives the PAG was instrumental in shaping the qualitative study, including the research questions. Their active involvement helped to ensure that that the study was sensitively designed, methodologically robust and ethically sound. The 2 nd PAG was formed in 2016 to give the project an overall steer. Patients in this group contributed to the work on the 'No' Audit and reviewed several CPFT policies such as the Seclusion and Segregation policy which has impacted on frontline practice. They also made a significant contribution to the study design for a funding application that was submitted by the PROMISE team to the National Institute for Health Research (NIHR). Both PAGs were supported by funding from East of England Collaboration for Leadership in Applied Health Research and Care (CLAHRC EoE) and were influential in different ways. An evaluation of the 2 nd PAG which was conducted in June 2017 showed very high satisfaction levels. The free text

  20. Dietary flavonoid derivatives enhance chemotherapeutic effect by inhibiting the DNA damage response pathway

    International Nuclear Information System (INIS)

    Kuo, Ching-Ying; Zupkó, István; Chang, Fang-Rong; Hunyadi, Attila; Wu, Chin-Chung; Weng, Teng-Song; Wang, Hui-Chun

    2016-01-01

    Flavonoids are the most common group of polyphenolic compounds and abundant in dietary fruits and vegetables. Diet high in vegetables or dietary flavonoid supplements is associated with reduced mortality rate for patients with breast cancer. Many studies have been proposed for mechanisms linking flavonoids to improving chemotherapy efficacy in many types of cancers, but data on this issue is still limited. Herein, we report on a new mechanism through which dietary flavonoids inhibit DNA damage checkpoints and repair pathways. We found that dietary flavonoids could inhibit Chk1 phosphorylation and decrease clonogenic cell growth once breast cancer cells receive ultraviolet irradiation, cisplatin, or etoposide treatment. Since the ATR-Chk1 pathway mainly involves response to DNA replication stress, we propose that flavonoid derivatives reduce the side effect of chemotherapy by improving the sensitivity of cycling cells. Therefore, we propose that increasing intake of common dietary flavonoids is beneficial to breast cancer patients who are receiving DNA-damaging chemotherapy, such as cisplatin or etoposide-based therapy. - Highlights: • First report on inhibition of both DNA damage and repair by dietary flavonoids • Dietary flavonoids inhibit cisplatin- and UV-induced Chk1 phosphorylation. • Flavonoids combined with cisplatin or UV treatment show notable growth inhibition. • Promising treatment proposal for patients who are receiving adjuvant chemotherapy

  1. Dietary flavonoid derivatives enhance chemotherapeutic effect by inhibiting the DNA damage response pathway

    Energy Technology Data Exchange (ETDEWEB)

    Kuo, Ching-Ying [Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Zupkó, István [Department of Pharmacodynamics and Biopharmacy, University of Szeged, Eötvös Utca 6, Szeged H-6720 (Hungary); Chang, Fang-Rong [Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Hunyadi, Attila [Institute of Pharmacognosy, Faculty of Pharmacy, University of Szeged, Eötvös Utca 6, Szeged H-6720 (Hungary); Wu, Chin-Chung; Weng, Teng-Song [Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Wang, Hui-Chun, E-mail: wanghc@kmu.edu.tw [Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); PhD Program in Translational Medicine, College of Medicine and PhD Program in Toxicology, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Research Center for Natural Product and Drug Development, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Translational Research Center and Cancer Center, Kaohsiung Medical University Hospital, Kaohsiung 80756, Taiwan (China); Department of Marine Biotechnology and Resources, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan (China); Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China)

    2016-11-15

    Flavonoids are the most common group of polyphenolic compounds and abundant in dietary fruits and vegetables. Diet high in vegetables or dietary flavonoid supplements is associated with reduced mortality rate for patients with breast cancer. Many studies have been proposed for mechanisms linking flavonoids to improving chemotherapy efficacy in many types of cancers, but data on this issue is still limited. Herein, we report on a new mechanism through which dietary flavonoids inhibit DNA damage checkpoints and repair pathways. We found that dietary flavonoids could inhibit Chk1 phosphorylation and decrease clonogenic cell growth once breast cancer cells receive ultraviolet irradiation, cisplatin, or etoposide treatment. Since the ATR-Chk1 pathway mainly involves response to DNA replication stress, we propose that flavonoid derivatives reduce the side effect of chemotherapy by improving the sensitivity of cycling cells. Therefore, we propose that increasing intake of common dietary flavonoids is beneficial to breast cancer patients who are receiving DNA-damaging chemotherapy, such as cisplatin or etoposide-based therapy. - Highlights: • First report on inhibition of both DNA damage and repair by dietary flavonoids • Dietary flavonoids inhibit cisplatin- and UV-induced Chk1 phosphorylation. • Flavonoids combined with cisplatin or UV treatment show notable growth inhibition. • Promising treatment proposal for patients who are receiving adjuvant chemotherapy.

  2. Chemotherapeutic potential of curcumin-bearing microcells against hepatocellular carcinoma in model animals

    Science.gov (United States)

    Farazuddin, Mohammad; Dua, Bhavyata; Zia, Qamar; Khan, Aijaz Ahmad; Joshi, Beenu; Owais, Mohammad

    2014-01-01

    Curcumin (diferuloylmethane) is found in large quantities in the roots of Curcuma longa. It possesses strong antioxidant and anti-inflammatory properties, and inhibits chemically-induced carcinogenesis in the skin, forestomach, colon, and liver. Unfortunately, the poor bioavailability and hydrophobicity of curcumin pose a major hurdle to its use as a potent anticancer agent. To circumvent some of these problems, we developed a novel, dual-core microcell formulation of curcumin. The encapsulation of curcumin in microcells increases its solubility and bioavailability, and facilitates slow release kinetics over extended periods. Besides being safe, these formulations do not bear any toxicity constraints, as revealed by in vitro and in vivo studies. Histopathological analysis revealed that curcumin-bearing microcells helped in regression of hepatocellular carcinoma and the maintenance of cellular architecture in liver tissue. Free curcumin had a very mild effect on cancer suppression. Empty (sham) microcells and microparticles failed to inhibit cancer cells. The novel curcumin formulation was found to suppress hepatocellular carcinoma efficiently in Swiss albino mice. PMID:24627632

  3. Chemotherapeutic potential of curcumin-bearing microcells against hepatocellular carcinoma in model animals

    Directory of Open Access Journals (Sweden)

    Farazuddin M

    2014-03-01

    Full Text Available Mohammad Farazuddin,1 Bhavyata Dua,2 Qamar Zia,1 Aijaz Ahmad Khan,3 Beenu Joshi,2 Mohammad Owais1 1Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, 2Immunology Division, National JALMA Institute for Leprosy and Other Mycobacterial Diseases (NJIL, Agra, 3Department of Anatomy, Jawaharlal Nehru Medical College, Aligarh Muslim University, Aligarh, India Abstract: Curcumin (diferuloylmethane is found in large quantities in the roots of Curcuma longa. It possesses strong antioxidant and anti-inflammatory properties, and inhibits chemically-induced carcinogenesis in the skin, forestomach, colon, and liver. Unfortunately, the poor bioavailability and hydrophobicity of curcumin pose a major hurdle to its use as a potent anticancer agent. To circumvent some of these problems, we developed a novel, dual-core microcell formulation of curcumin. The encapsulation of curcumin in microcells increases its solubility and bioavailability, and facilitates slow release kinetics over extended periods. Besides being safe, these formulations do not bear any toxicity constraints, as revealed by in vitro and in vivo studies. Histopathological analysis revealed that curcumin-bearing microcells helped in regression of hepatocellular carcinoma and the maintenance of cellular architecture in liver tissue. Free curcumin had a very mild effect on cancer suppression. Empty (sham microcells and microparticles failed to inhibit cancer cells. The novel curcumin formulation was found to suppress hepatocellular carcinoma efficiently in Swiss albino mice. Keywords: diferuloylmethane, carcinogenesis, microparticle, nanocells, cancer, Curcuma longa

  4. Baicalein attenuates vinorelbine-induced vascular endothelial cell injury and chemotherapeutic phlebitis in rabbits.

    Science.gov (United States)

    Ge, Gang-Feng; Shi, Wei-Wen; Yu, Chen-Huan; Jin, Xiao-Yin; Zhang, Huan-Huan; Zhang, Wen-You; Wang, Lu-Chen; Yu, Bing

    2017-03-01

    Chemotherapy is one of the major strategies for cancer treatment. Several antineoplastic drugs including vinorelbine (VRB) are commonly intravenously infused and liable to cause serious phlebitis. The therapeutic drugs for preventing this complication are limited. In this study, the mechanism of baicalein (BCN) was investigated on VRB-induced phlebitis in vivo and vascular endothelial cell injury in vitro. Treatment with BCN obviously attenuated vascular endothelial cell loss, edema, inflammatory cell infiltration and blood clots, and reduced the serum levels of TNF-α, IL-1β, IL-6 and ICAM-1 in the rabbit model of phlebitis induced by intravenous injection of VRB compared with vehicle. Further tests in vitro demonstrated that BCN lessened VRB-induced endothelial cell apoptosis, decreased intracellular ROS levels, suppressed phosphorylation of p38 and eventually inhibited activation of NF-κB signaling pathway. And these effects could be reversed by p38 agonist P79350. These results suggested that BCN exerted the protective effects against VRB-induced endothelial disruption in the rabbit model of phlebitis via inhibition of intracellular ROS generation and inactivation of p38/NF-κB pathway, leading to the decreased production of pro-inflammatory cytokines. Thus, BCN could be used as a potential agent for the treatment of phlebitis. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. A co-delivery nanosystem of chemotherapeutics and DNAzyme overcomes cancer drug resistance and metastasis

    Science.gov (United States)

    Sun, Shu-Pin; Liu, Ching-Ping; Huang, I.-Ping; Chu, Chia-Hui; Chung, Ming-Fang; Cheng, Shih-Hsun; Lin, Shu-Yi; Lo, Leu-Wei

    2017-12-01

    Multidrug resistance (MDR) constitutes a major problem in the management of cancer and cancer metastasized from primary-source tumor causes cancer-related deaths. Our new approach is the co-delivery of chemotherapy drugs with a transcription-factor-targeting genetic agent to simultaneously inhibit the growth and metastasis of cancer cells. C-Jun is a transcription factor that regulates multidrug resistance-associated protein 1 (MRP1) pump efflux transcription and tumor metastasis. In this work, we reported that mesoporous silica nanoparticles (MSNs) can be functionalized to co-deliver doxorubicin (Dox) and DNAzyme (Dz) to increase cancer cell killing in an additive fashion. The MSNs were sequentially conjugated with Dox into the MSNs’ nanochannels and Dz onto the MSNs’ outermost surface to target c-Jun as the Dox@MSN-Dz co-delivery system. The Dox-resistant PC-3 cells treated with Dox@MSN-Dz efficiently enhanced the intracellular Dox concentration due to the abrogation of Dox-induced MRP1 expression through the downregulation of c-Jun expression by Dz. Additionally, significant reductions in invasion and migration related to metastasis were also observed in cells treated with Dox@MSN-Dz. Therefore, our results contribute new insight to the treatment of MDR combined metastatic cancer cells, worthwhile for studying its potential for development in clinical translation.

  6. Perpendicular recording: the promise and the problems

    International Nuclear Information System (INIS)

    Wood, Roger; Sonobe, Yoshiaki; Jin Zhen; Wilson, Bruce

    2001-01-01

    Perpendicular recording has long been advocated as a means of achieving the highest areal densities. In particular, in the context of the 'superparamagnetic limit', perpendicular recording with a soft underlayer promises several key advantages. These advantages include a higher coercivity, thicker media that should permit smaller diameter grains and higher signal-to-noise ratio. Also, the sharper edge-writing will facilitate recording at very high track densities (lower bit aspect ratio). Recent demonstrations of the technology have shown densities comparable with the highest densities reported for longitudinal recording. This paper further examines the promise that perpendicular recording will deliver an increase in areal density two to eight times higher than that achievable with longitudinal recording. There are a number of outstanding issues but the key challenge is to create a low-noise medium with a coercivity that is high and is much larger than the remanent magnetization

  7. The deepwater Gulf of Mexico : promises delivered?

    International Nuclear Information System (INIS)

    Pickering, D.R.

    1999-01-01

    A summary review of deepwater Gulf of Mexico (GOM) oil production was presented for the years 1989 to 1998. Trends and prospects in deepwater GOM production and leasing were assessed. Promises and forecasts made in the early 1990s were compared with what actually happened since then. Forecasts in the early 1990s promised deeper, faster and cheaper developments in the deepwater Gulf. Results of the comparison showed that the prognosticators were correct on all three counts. Regarding the future of the Gulf, one can be justified in being optimistic in so far as more experience, robust economics, more and cheaper rigs can be taken as reliable indicators of optimism. In contrast, there are certain negatives to consider, such as low commodity prices, budget constraints, lease expirations, technical challenges and increased competition. . 12 figs

  8. Putative neuroprotective agents in neuropsychiatric disorders.

    Science.gov (United States)

    Dodd, Seetal; Maes, Michael; Anderson, George; Dean, Olivia M; Moylan, Steven; Berk, Michael

    2013-04-05

    In many individuals with major neuropsychiatric disorders including depression, bipolar disorder and schizophrenia, their disease characteristics are consistent with a neuroprogressive illness. This includes progressive structural brain changes, cognitive and functional decline, poorer treatment response and an increasing vulnerability to relapse with chronicity. The underlying molecular mechanisms of neuroprogression are thought to include neurotrophins and regulation of neurogenesis and apoptosis, neurotransmitters, inflammatory, oxidative and nitrosative stress, mitochondrial dysfunction, cortisol and the hypothalamic-pituitary-adrenal axis, and epigenetic influences. Knowledge of the involvement of each of these pathways implies that specific agents that act on some or multiple of these pathways may thus block this cascade and have neuroprotective properties. This paper reviews the potential of the most promising of these agents, including lithium and other known psychotropics, aspirin, minocycline, statins, N-acetylcysteine, leptin and melatonin. These agents are putative neuroprotective agents for schizophrenia and mood disorders. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Promising Products for Printing and Publishing Market

    Directory of Open Access Journals (Sweden)

    Renata Činčikaitė

    2011-04-01

    Full Text Available The article surveys printing and publishing market and its strong and weak aspects. The concept of a new product is described as well as its lifetime and the necessity of its introduction to the market. The enterprise X operating on the market is analyzed, its strong and weak characteristics are presented. The segmentation of the company consumers is performed. On the basis of the performed analysis the potential promising company products are defined.Article in Lithuanian

  10. Melanoma Vaccines: Mixed Past, Promising Future

    Science.gov (United States)

    Ozao-Choy, Junko; Lee, Delphine J.; Faries, Mark B.

    2014-01-01

    Synopsis Cancer vaccines were one of the earliest forms of immunotherapy to be investigated. Past attempts to vaccinate against cancer, including melanoma, have mixed results, revealing the complexity of what was thought to be a simple concept. However, several recent successes and the combination of improved knowledge of tumor immunology and the advent of new immunomodulators make vaccination a promising strategy for the future. PMID:25245965

  11. DMH1 (4-[6-(4-isopropoxyphenylpyrazolo[1,5-a]pyrimidin-3-yl]quinoline inhibits chemotherapeutic drug-induced autophagy

    Directory of Open Access Journals (Sweden)

    Yue Sheng

    2015-07-01

    Full Text Available Our previous work found that DMH1 (4-[6-(4-isopropoxyphenylpyrazolo [1,5-a]pyrimidin-3-yl]quinoline was a novel autophagy inhibitor. Here, we aimed to investigate the effects of DMH1 on chemotherapeutic drug-induced autophagy as well as the efficacy of chemotherapeutic drugs in different cancer cells. We found that DMH1 inhibited tamoxifen- and cispcis-diaminedichloroplatinum (II (CDDP-induced autophagy responses in MCF-7 and HeLa cells, and potentiated the anti-tumor activity of tamoxifen and CDDP for both cells. DMH1 inhibited 5-fluorouracil (5-FU-induced autophagy responses in MCF-7 and HeLa cells, but did not affect the anti-tumor activity of 5-FU for these two cell lines. DMH1 itself did not induce cell death in MCF-7 and HeLa cells, but inhibited the proliferation of these cells. In conclusion, DMH1 inhibits chemotherapeutic drug-induced autophagy response and the enhancement of efficacy of chemotherapeutic drugs by DMH1 is dependent on the cell sensitivity to drugs.

  12. Prediction of chemotherapeutic response in bladder cancer using K-means clustering of dynamic contrast-enhanced (DCE)-MRI pharmacokinetic parameters.

    Science.gov (United States)

    Nguyen, Huyen T; Jia, Guang; Shah, Zarine K; Pohar, Kamal; Mortazavi, Amir; Zynger, Debra L; Wei, Lai; Yang, Xiangyu; Clark, Daniel; Knopp, Michael V

    2015-05-01

    To apply k-means clustering of two pharmacokinetic parameters derived from 3T dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to predict the chemotherapeutic response in bladder cancer at the mid-cycle timepoint. With the predetermined number of three clusters, k-means clustering was performed on nondimensionalized Amp and kep estimates of each bladder tumor. Three cluster volume fractions (VFs) were calculated for each tumor at baseline and mid-cycle. The changes of three cluster VFs from baseline to mid-cycle were correlated with the tumor's chemotherapeutic response. Receiver-operating-characteristics curve analysis was used to evaluate the performance of each cluster VF change as a biomarker of chemotherapeutic response in bladder cancer. The k-means clustering partitioned each bladder tumor into cluster 1 (low kep and low Amp), cluster 2 (low kep and high Amp), cluster 3 (high kep and low Amp). The changes of all three cluster VFs were found to be associated with bladder tumor response to chemotherapy. The VF change of cluster 2 presented with the highest area-under-the-curve value (0.96) and the highest sensitivity/specificity/accuracy (96%/100%/97%) with a selected cutoff value. The k-means clustering of the two DCE-MRI pharmacokinetic parameters can characterize the complex microcirculatory changes within a bladder tumor to enable early prediction of the tumor's chemotherapeutic response. © 2014 Wiley Periodicals, Inc.

  13. Baicalein attenuates vinorelbine-induced vascular endothelial cell injury and chemotherapeutic phlebitis in rabbits

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Gang-Feng [Zhejiang Chinese Medical University, Hangzhou 310053 (China); Shi, Wei-Wen [Zhejiang Medical Science and Education Development Center, Hangzhou 310006 (China); Yu, Chen-Huan; Jin, Xiao-Yin; Zhang, Huan-Huan; Zhang, Wen-You [Key Laboratory of Experimental Animal and Safety Evaluation, Zhejiang Academy of Medical Sciences, Hangzhou 310013 (China); Wang, Lu-Chen [Zhejiang Chinese Medical University, Hangzhou 310053 (China); Yu, Bing, E-mail: Jellycook2002@163.com [Zhejiang Chinese Medical University, Hangzhou 310053 (China)

    2017-03-01

    Chemotherapy is one of the major strategies for cancer treatment. Several antineoplastic drugs including vinorelbine (VRB) are commonly intravenously infused and liable to cause serious phlebitis. The therapeutic drugs for preventing this complication are limited. In this study, the mechanism of baicalein (BCN) was investigated on VRB-induced phlebitis in vivo and vascular endothelial cell injury in vitro. Treatment with BCN obviously attenuated vascular endothelial cell loss, edema, inflammatory cell infiltration and blood clots, and reduced the serum levels of TNF-α, IL-1β, IL-6 and ICAM-1 in the rabbit model of phlebitis induced by intravenous injection of VRB compared with vehicle. Further tests in vitro demonstrated that BCN lessened VRB-induced endothelial cell apoptosis, decreased intracellular ROS levels, suppressed phosphorylation of p38 and eventually inhibited activation of NF-κB signaling pathway. And these effects could be reversed by p38 agonist P79350. These results suggested that BCN exerted the protective effects against VRB-induced endothelial disruption in the rabbit model of phlebitis via inhibition of intracellular ROS generation and inactivation of p38/NF-κB pathway, leading to the decreased production of pro-inflammatory cytokines. Thus, BCN could be used as a potential agent for the treatment of phlebitis. - Highlights: • Baicalein attenuated vinorelbine-induced vascular endothelial cell apoptosis. • Baicalein inhibited vinorelbine-induced oxidative stress in HUVECs. • Baicalein inhibited activation of p38/NF-κB signaling. • Baicalein attenuated vinorelbine-induced phlebitis and inflammation in rabbits.

  14. Baicalein attenuates vinorelbine-induced vascular endothelial cell injury and chemotherapeutic phlebitis in rabbits

    International Nuclear Information System (INIS)

    Ge, Gang-Feng; Shi, Wei-Wen; Yu, Chen-Huan; Jin, Xiao-Yin; Zhang, Huan-Huan; Zhang, Wen-You; Wang, Lu-Chen; Yu, Bing

    2017-01-01

    Chemotherapy is one of the major strategies for cancer treatment. Several antineoplastic drugs including vinorelbine (VRB) are commonly intravenously infused and liable to cause serious phlebitis. The therapeutic drugs for preventing this complication are limited. In this study, the mechanism of baicalein (BCN) was investigated on VRB-induced phlebitis in vivo and vascular endothelial cell injury in vitro. Treatment with BCN obviously attenuated vascular endothelial cell loss, edema, inflammatory cell infiltration and blood clots, and reduced the serum levels of TNF-α, IL-1β, IL-6 and ICAM-1 in the rabbit model of phlebitis induced by intravenous injection of VRB compared with vehicle. Further tests in vitro demonstrated that BCN lessened VRB-induced endothelial cell apoptosis, decreased intracellular ROS levels, suppressed phosphorylation of p38 and eventually inhibited activation of NF-κB signaling pathway. And these effects could be reversed by p38 agonist P79350. These results suggested that BCN exerted the protective effects against VRB-induced endothelial disruption in the rabbit model of phlebitis via inhibition of intracellular ROS generation and inactivation of p38/NF-κB pathway, leading to the decreased production of pro-inflammatory cytokines. Thus, BCN could be used as a potential agent for the treatment of phlebitis. - Highlights: • Baicalein attenuated vinorelbine-induced vascular endothelial cell apoptosis. • Baicalein inhibited vinorelbine-induced oxidative stress in HUVECs. • Baicalein inhibited activation of p38/NF-κB signaling. • Baicalein attenuated vinorelbine-induced phlebitis and inflammation in rabbits.

  15. Fisetin Enhances Chemotherapeutic Effect of Cabazitaxel against Human Prostate Cancer Cells.

    Science.gov (United States)

    Mukhtar, Eiman; Adhami, Vaqar Mustafa; Siddiqui, Imtiaz Ahmad; Verma, Ajit Kumar; Mukhtar, Hasan

    2016-12-01

    Although treatment of prostate cancer has improved over the past several years, taxanes, such as cabazitaxel, remain the only form of effective chemotherapy that improves survival in patients with metastatic castration-resistant prostate cancer. However, the effectiveness of this class of drugs has been associated with various side effects and drug resistance. We previously reported that fisetin, a hydroxyflavone, is a microtubule-stabilizing agent and inhibits prostate cancer cell proliferation, migration, and invasion and suggested its use as an adjuvant for treatment of prostate and other cancer types. In this study, we investigated the effect of fisetin in combination with cabazitaxel with the objective to achieve maximum therapeutic benefit, reduce dose and toxicity, and minimize or delay the induction of drug resistance and metastasis. Our data show for the first time that a combination of fisetin (20 μmol/L) enhances cabazitaxel (5 nmol/L) and synergistically reduces 22Rν1, PC-3M-luc-6, and C4-2 cell viability and metastatic properties with minimal adverse effects on normal prostate epithelial cells. In addition, the combination of fisetin with cabazitaxel was associated with inhibition of proliferation and enhancement of apoptosis. Furthermore, combination treatment resulted in the inhibition of tumor growth, invasion, and metastasis when assessed in two in vivo xenograft mouse models. These results provide evidence that fisetin may have therapeutic benefit for patients with advanced prostate cancer through enhancing the efficacy of cabazitaxel under both androgen-dependent and androgen-independent conditions. This study underscores the benefit of the combination of fisetin with cabazitaxel for the treatment of advanced and resistant prostate cancer and possibly other cancer types. Mol Cancer Ther; 15(12); 2863-74. ©2016 AACR. ©2016 American Association for Cancer Research.

  16. Identification of novel markers that demarcate the nucleolus during severe stress and chemotherapeutic treatment.

    Science.gov (United States)

    Su, Haitong; Kodiha, Mohamed; Lee, Sunghoon; Stochaj, Ursula

    2013-01-01

    The nucleolus, the ribosomal factory of the cell, has emerged as a key player that regulates many aspects of cell biology. Several thousand proteins associate at least transiently with nucleoli, thereby generating a highly dynamic compartment with a protein profile which is sensitive to changes in cell physiology and pharmacological agents. Powerful tools that reliably demarcate the nucleoli are a prerequisite to measure their composition and activities. Previously, we developed quantitative methods to measure fluorescently labeled molecules in nucleoli. While these tools identify nucleoli under control and mild stress conditions, the accurate detection of nucleolar boundaries under harsh experimental conditions is complicated by the lack of appropriate markers for the nucleolar compartment. Using fluorescence microscopy we have now identified new marker proteins to detect nucleoli upon (a) severe stress and (b) drug treatments that trigger a pronounced reorganization of nucleoli. Our results demonstrate that nucleolin is an ideal marker to delimit nucleoli when cells are exposed to heat or oxidative stress. Furthermore, we show for the first time that cellular apoptosis susceptibility protein (CAS) and human antigen R protein (HuR) are excluded from nucleoli and can be employed to delimit these compartments under severe conditions that redistribute major nucleolar proteins. As proof-of-principle, we used these markers to demarcate nucleoli in cells treated with pharmacological compounds that disrupt the nucleolar organization. Furthermore, to gain new insights into the biology of the nucleolus, we applied our protocols and quantified stress- and drug-induced changes in nucleolar organization and function. Finally, we show that CAS, HuR and nucleolin not only identify nucleoli in optical sections, but are also suitable to demarcate the nucleolar border following 3D reconstruction. Taken together, our studies present novel marker proteins that delimit nucleoli with

  17. Identification of novel markers that demarcate the nucleolus during severe stress and chemotherapeutic treatment.

    Directory of Open Access Journals (Sweden)

    Haitong Su

    Full Text Available The nucleolus, the ribosomal factory of the cell, has emerged as a key player that regulates many aspects of cell biology. Several thousand proteins associate at least transiently with nucleoli, thereby generating a highly dynamic compartment with a protein profile which is sensitive to changes in cell physiology and pharmacological agents. Powerful tools that reliably demarcate the nucleoli are a prerequisite to measure their composition and activities. Previously, we developed quantitative methods to measure fluorescently labeled molecules in nucleoli. While these tools identify nucleoli under control and mild stress conditions, the accurate detection of nucleolar boundaries under harsh experimental conditions is complicated by the lack of appropriate markers for the nucleolar compartment. Using fluorescence microscopy we have now identified new marker proteins to detect nucleoli upon (a severe stress and (b drug treatments that trigger a pronounced reorganization of nucleoli. Our results demonstrate that nucleolin is an ideal marker to delimit nucleoli when cells are exposed to heat or oxidative stress. Furthermore, we show for the first time that cellular apoptosis susceptibility protein (CAS and human antigen R protein (HuR are excluded from nucleoli and can be employed to delimit these compartments under severe conditions that redistribute major nucleolar proteins. As proof-of-principle, we used these markers to demarcate nucleoli in cells treated with pharmacological compounds that disrupt the nucleolar organization. Furthermore, to gain new insights into the biology of the nucleolus, we applied our protocols and quantified stress- and drug-induced changes in nucleolar organization and function. Finally, we show that CAS, HuR and nucleolin not only identify nucleoli in optical sections, but are also suitable to demarcate the nucleolar border following 3D reconstruction. Taken together, our studies present novel marker proteins that

  18. Nano-BCG: A Promising Delivery System for Treatment of Human Bladder Cancer.

    Science.gov (United States)

    Buss, Julieti Huch; Begnini, Karine Rech; Bender, Camila Bonemann; Pohlmann, Adriana R; Guterres, Silvia S; Collares, Tiago; Seixas, Fabiana Kömmling

    2017-01-01

    Mycobacterium bovis bacillus Calmette-Guerin (BCG) remains at the forefront of immunotherapy for treating bladder cancer patients. However, the incidence of recurrence and progression to invasive cancer is commonly observed. There are no established effective intravesical therapies available for patients, whose tumors recur following BCG treatment, representing an important unmet clinical need. In addition, there are very limited options for patients who do not respond to or tolerate chemotherapy due to toxicities, resulting in poor overall treatment outcomes. Within this context, nanotechnology is an emergent and promising tool for: (1) controlling drug release for extended time frames, (2) combination therapies due to the ability to encapsulate multiple drugs simultaneously, (3) reducing systemic side effects, (4) increasing bioavailability, (5) and increasing the viability of various routes of administration. Moreover, bladder cancer is often characterized by high mutation rates and over expression of tumor antigens on the tumor cell surface. Therapeutic targeting of these biomolecules may be improved by nanotechnology strategies. In this mini-review, we discuss how nanotechnology can help overcome current obstacles in bladder cancer treatment, and how nanotechnology can facilitate combination chemotherapeutic and BCG immunotherapies for the treatment of non-muscle invasive urothelial bladder cancer.

  19. Nano-BCG: A Promising Delivery System for Treatment of Human Bladder Cancer

    Directory of Open Access Journals (Sweden)

    Julieti Huch Buss

    2018-01-01

    Full Text Available Mycobacterium bovis bacillus Calmette–Guerin (BCG remains at the forefront of immunotherapy for treating bladder cancer patients. However, the incidence of recurrence and progression to invasive cancer is commonly observed. There are no established effective intravesical therapies available for patients, whose tumors recur following BCG treatment, representing an important unmet clinical need. In addition, there are very limited options for patients who do not respond to or tolerate chemotherapy due to toxicities, resulting in poor overall treatment outcomes. Within this context, nanotechnology is an emergent and promising tool for: (1 controlling drug release for extended time frames, (2 combination therapies due to the ability to encapsulate multiple drugs simultaneously, (3 reducing systemic side effects, (4 increasing bioavailability, (5 and increasing the viability of various routes of administration. Moreover, bladder cancer is often characterized by high mutation rates and over expression of tumor antigens on the tumor cell surface. Therapeutic targeting of these biomolecules may be improved by nanotechnology strategies. In this mini-review, we discuss how nanotechnology can help overcome current obstacles in bladder cancer treatment, and how nanotechnology can facilitate combination chemotherapeutic and BCG immunotherapies for the treatment of non-muscle invasive urothelial bladder cancer.

  20. NIR-Cyanine Dye Linker: a Promising Candidate for Isochronic Fluorescence Imaging in Molecular Cancer Diagnostics and Therapy Monitoring.

    Science.gov (United States)

    Komljenovic, Dorde; Wiessler, Manfred; Waldeck, Waldemar; Ehemann, Volker; Pipkorn, Ruediger; Schrenk, Hans-Hermann; Debus, Jürgen; Braun, Klaus

    2016-01-01

    Personalized anti-cancer medicine is boosted by the recent development of molecular diagnostics and molecularly targeted drugs requiring rapid and efficient ligation routes. Here, we present a novel approach to synthetize a conjugate able to act simultaneously as an imaging and as a chemotherapeutic agent by coupling functional peptides employing solid phase peptide synthesis technologies. Development and the first synthesis of a fluorescent dye with similarity in the polymethine part of the Cy7 molecule whose indolenine-N residues were substituted with a propylene linker are described. Methylating agent temozolomide is functionalized with a tetrazine as a diene component whereas Cy7-cell penetrating peptide conjugate acts as a dienophilic reaction partner for the inverse Diels-Alder click chemistry-mediated ligation route yielding a theranostic conjugate, 3-mercapto-propionic-cyclohexenyl-Cy7-bis-temozolomide-bromide-cell penetrating peptide. Synthesis route described here may facilitate targeted delivery of the therapeutic compound to achieve sufficient local concentrations at the target site or tissue. Its versatility allows a choice of adequate imaging tags applicable in e.g. PET, SPECT, CT, near-infrared imaging, and therapeutic substances including cytotoxic agents. Imaging tags and therapeutics may be simultaneously bound to the conjugate applying click chemistry. Theranostic compound presented here offers a solid basis for a further improvement of cancer management in a precise, patient-specific manner.

  1. Radiopharmaceutical scanning agents

    International Nuclear Information System (INIS)

    1976-01-01

    This invention is directed to dispersions useful in preparing radiopharmaceutical scanning agents, to technetium labelled dispersions, to methods for preparing such dispersions and to their use as scanning agents

  2. Taskable Reactive Agent Communities

    National Research Council Canada - National Science Library

    Myers, Karen

    2002-01-01

    The focus of Taskable Reactive Agent Communities (TRAC) project was to develop mixed-initiative technology to enable humans to supervise and manage teams of agents as they perform tasks in dynamic environments...

  3. Users, Bystanders and Agents

    DEFF Research Database (Denmark)

    Krummheuer, Antonia Lina

    2015-01-01

    Human-agent interaction (HAI), especially in the field of embodied conversational agents (ECA), is mainly construed as dyadic communication between a human user and a virtual agent. This is despite the fact that many application scenarios for future ECAs involve the presence of others. This paper...

  4. Asymptotically Optimal Agents

    OpenAIRE

    Lattimore, Tor; Hutter, Marcus

    2011-01-01

    Artificial general intelligence aims to create agents capable of learning to solve arbitrary interesting problems. We define two versions of asymptotic optimality and prove that no agent can satisfy the strong version while in some cases, depending on discounting, there does exist a non-computable weak asymptotically optimal agent.

  5. Reasoning about emotional agents

    NARCIS (Netherlands)

    Meyer, J.-J.

    In this paper we discuss the role of emotions in artificial agent design, and the use of logic in reasoning about the emotional or affective states an agent can reside in. We do so by extending the KARO framework for reasoning about rational agents appropriately. In particular we formalize in

  6. Does environmental archaeology need an ethical promise?

    DEFF Research Database (Denmark)

    Riede, Felix; Andersen, Per; Price, Neil

    2016-01-01

    formalized ethical codes or promises that not only guide the dissemination of data but oblige scientists to relate to fundamentally political issues. This article couples a survey of the recent environmental ethics literature with two case studies of how past natural hazards have affected vulnerable...... societies in Europe?s prehistory. We ask whether cases of past calamities and their societal effects should play a greater role in public debates and whether archaeologists working with past environmental hazards should be more outspoken in their ethical considerations. We offer no firm answers, but suggest...... that archaeologists engage with debates in human?environment relations at this interface between politics, public affairs and science....

  7. Sensitization of melanoma cells to alkylating agent-induced DNA damage and cell death via orchestrating oxidative stress and IKK? inhibition

    OpenAIRE

    Tse, Anfernee Kai-Wing; Chen, Ying-Jie; Fu, Xiu-Qiong; Su, Tao; Li, Ting; Guo, Hui; Zhu, Pei-Li; Kwan, Hiu-Yee; Cheng, Brian Chi-Yan; Cao, Hui-Hui; Lee, Sally Kin-Wah; Fong, Wang-Fun; Yu, Zhi-Ling

    2017-01-01

    Nitrosourea represents one of the most active classes of chemotherapeutic alkylating agents for metastatic melanoma. Treatment with nitrosoureas caused severe systemic side effects which hamper its clinical use. Here, we provide pharmacological evidence that reactive oxygen species (ROS) induction and IKKβ inhibition cooperatively enhance nitrosourea-induced cytotoxicity in melanoma cells. We identified SC-514 as a ROS-inducing IKKβ inhibitor which enhanced the function of nitrosoureas. Eleva...

  8. Radiographic scanning agent

    International Nuclear Information System (INIS)

    Bevan, J.A.

    1983-01-01

    This invention relates to radiodiagnostic agents and more particularly to a composition and method for preparing a highly effective technetium-99m-based bone scanning agent. One deficiency of x-ray examination is the inability of that technique to detect skeletal metastases in their incipient stages. It has been discovered that the methanehydroxydiphosphonate bone mineral-seeking agent is unique in that it provides the dual benefits of sharp radiographic imaging and excellent lesion detection when used with technetium-99m. This agent can also be used with technetium-99m for detecting soft tissue calcification in the manner of the inorganic phosphate radiodiagnostic agents

  9. Agente adaptable y aprendizaje

    Directory of Open Access Journals (Sweden)

    Arturo Angel Lara Rivero

    2013-05-01

    Full Text Available En este trabajo se contrasta el concepto de agente programado con el de agente complejo adaptable, se presenta una nueva visión ligada al aprendizaje y la estructura del agente. La imagen del agente se analiza considerando los modelos internos, la práctica, el concepto de rutina y la influencia en su comportamiento, y la importancia del aprendizaje ex ante y ex post. Por último se muestra que la resolución de problemas está sujeta a restricciones del agente y se describen las formas de explorar el espacio de soluciones mediante tres tipos de exploración: exhaustiva, aleatoria y selectiva.

  10. Why do people keep their promises? An overview of strategic commitment

    Directory of Open Access Journals (Sweden)

    Miranda del Corral

    2015-07-01

    Full Text Available Strategic commitments, such as promises and threats, pose several problems to the standard model of economic rationality: first, they can only arise when there is an incentive to free ride; second, they need to be credible in order to manipulate the others' behaviour; third, once the commitment has succeeded, it is no longer in the agent's self interest to fulfil her commitment. Why, then, do people keep their promises (and threats? This paper reviews the literature concerning the problem of commitment within the scope of pro-sociality and cooperation, and examines two mechanisms that enable credibility and trust: reputation and social emotions

  11. SMIFH2-mediated mDia formin functional inhibition potentiates chemotherapeutic targeting of human ovarian cancer spheroids.

    Science.gov (United States)

    Ziske, Megan A; Pettee, Krista M; Khaing, MaNada; Rubinic, Kaitlin; Eisenmann, Kathryn M

    2016-03-25

    Due to a lack of effective screening or prevention protocol for epithelial ovarian cancer (EOC), there is a critical unmet need to develop therapeutic interventions for EOC treatment. EOC metastasis is unique. Initial dissemination is not primarily hematogenous, yet is facilitated through shedding of primary tumor cells into the peritoneal fluid and accumulating ascites. Increasingly, isolated patient spheroids point to a clinical role for spheroids in EOC metastasis. EOC spheroids are highly invasive structures that disseminate upon peritoneal mesothelium, and visceral tissues including liver and omentum. Selection for this subset of chemoresistant EOC cells could influence disease progression and/or recurrence. Thus, targeting spheroid integrity/structure may improve the chemotherapeutic responsiveness of EOC. We discovered a critical role for mammalian Diaphanous (mDia)-related formin-2 in maintaining EOC spheroid structure. Both mDia2 and the related mDia1 regulate F-actin networks critical to maintain cell-cell contacts and the integrity of multi-cellular epithelial sheets. We investigated if mDia2 functional inhibition via a small molecule inhibitor SMIFH2 combined with chemotherapeutics, such as taxol and cisplatin, inhibits the viability of EOC monolayers and clinically relevant spheroids. SMIFH2-mediated mDia formin inhibition significantly reduced both ES2 and Skov3 EOC monolayer viability while spheroid viability was minimally impacted only at the highest concentrations. Combining either cisplatin or taxol with SMIFH2 did not significantly enhance the effects of either drug alone in ES2 monolayers, while Skov3 monolayers treated with taxol or cisplatin and SMIFH2 showed significant additive inhibition of viability. ES2 spheroids were highly responsive with clear additive anti-viability effects with dual taxol or cisplatin when combined with SMIFH2 treatments. While combined taxol with SMIFH2 in spheroids showed an additive effect relative to single

  12. Status and promise of fuel cell technology

    Energy Technology Data Exchange (ETDEWEB)

    Williams, M.C. [National Energy Technology Lab., Pittsburgh, PA (United States). Dept. of Energy

    2001-09-01

    The niche or early entry market penetration by ONSI and its phosphoric acid fuel cell technology has proven that fuel cells are reliable and suitable for premium power and other opportunity fuel niche market applications. Now, new fuel cell technologies - solid oxide fuel cells, molten carbonate fuel cells, and polymer electrolyte fuel cells - are being developed for near-term distributed generation shortly after 2003. Some of the evolving fuel cell systems are incorporating gas turbines in hybrid configurations. The combination of the gas turbine with the fuel cell promises to lower system costs and increase efficiency to enhance market penetration. Market estimates indicate that significant early entry markets exist to sustain the initially high cost of some distributed generation technologies. However, distributed generation technologies must have low introductory first cost, low installation cost, and high system reliability to be viable options in competitive commercial and industrial markets. In the long-term, solid state fuel cell technology with stack costs under $100/kilowatt (kW) promises deeper and wider market penetration in a range of applications including a residential, auxillary power, and the mature distributed generation markets. The solid state energy conversion alliance (SECA) with its vision for fuel cells in 2010 was recently formed to commercialize solid state fuel cells and realize the full potential of the fuel cell technology. Ultimately, the SECA concept could lead to megawatt-size fuel-cell systems for commercial and industrial applications and Vision 21 fuel cell turbine hybrid energy plants in 2015. (orig.)

  13. Promises in intelligent plant control systems

    International Nuclear Information System (INIS)

    Otaduy, P.J.

    1987-01-01

    The control system is the brain of a power plant. The traditional goal of control systems has been productivity. However, in nuclear power plants the potential for disaster requires safety to be the dominant concern, and the worldwide political climate demands trustworthiness for nuclear power plants. To keep nuclear generation as a viable option for power in the future, trust is the essential critical goal which encompasses all others. In most of today's nuclear plants the control system is a hybrid of analog, digital, and human components that focuses on productivity and operates under the protective umbrella of an independent engineered safety system. Operation of the plant is complex, and frequent challenges to the safety system occur which impact on their trustworthiness. Advances in nuclear reactor design, computer sciences, and control theory, and in related technological areas such as electronics and communications as well as in data storage, retrieval, display, and analysis have opened a promise for control systems with more acceptable human brain-like capabilities to pursue the required goals. This paper elaborates on the promise of futuristic nuclear power plants with intelligent control systems and addresses design requirements and implementation approaches

  14. Biosurfactants: Promising Molecules for Petroleum Biotechnology Advances

    Directory of Open Access Journals (Sweden)

    DARNE GERMANO DE ALMEIDA

    2016-10-01

    Full Text Available The growing global demand for sustainable technologies that improves the efficiency of petrochemical processes in the oil industry has driven advances in petroleum biotechnology in recent years. Petroleum industry uses substantial amounts of petrochemical-based synthetic surfactants in its activities as mobilizing agents to increase the availability or recovery of hydrocarbons as well as many other applications related to extraction, treatment, cleaning and transportation. However, biosurfactants have several potential applications for use across the oil processing chain and in the formulations of petrochemical products such as emulsifying/demulsifying agents, anticorrosive, biocides for sulphate-reducing bacteria, fuel formulation, extraction of bitumen from tar sands and many other innovative applications. Due to their versatility and proven efficiency, biosurfactants are often presented as valuable versatile tools that can transform and modernise petroleum biotechnology in an attempt to provide a true picture of state of the art and directions or use in the oil industry. We believe that biosurfactants are going to have a significant role in many future applications in the oil industries and in this review therefore, we highlight recent important relevant applications, patents disclosures and potential future applications for biosurfactants in petroleum and related industries.

  15. Biosurfactants: Promising Molecules for Petroleum Biotechnology Advances.

    Science.gov (United States)

    De Almeida, Darne G; Soares Da Silva, Rita de Cássia F; Luna, Juliana M; Rufino, Raquel D; Santos, Valdemir A; Banat, Ibrahim M; Sarubbo, Leonie A

    2016-01-01

    The growing global demand for sustainable technologies that improves the efficiency of petrochemical processes in the oil industry has driven advances in petroleum biotechnology in recent years. Petroleum industry uses substantial amounts of petrochemical-based synthetic surfactants in its activities as mobilizing agents to increase the availability or recovery of hydrocarbons as well as many other applications related to extraction, treatment, cleaning, and transportation. However, biosurfactants have several potential applications for use across the oil processing chain and in the formulations of petrochemical products such as emulsifying/demulsifying agents, anticorrosive, biocides for sulfate-reducing bacteria, fuel formulation, extraction of bitumen from tar sands, and many other innovative applications. Due to their versatility and proven efficiency, biosurfactants are often presented as valuable versatile tools that can transform and modernize petroleum biotechnology in an attempt to provide a true picture of state of the art and directions or use in the oil industry. We believe that biosurfactants are going to have a significant role in many future applications in the oil industries and in this review therefore, we highlight recent important relevant applications, patents disclosures and potential future applications for biosurfactants in petroleum and related industries.

  16. Biosurfactants: Promising Molecules for Petroleum Biotechnology Advances

    Science.gov (United States)

    De Almeida, Darne G.; Soares Da Silva, Rita de Cássia F.; Luna, Juliana M.; Rufino, Raquel D.; Santos, Valdemir A.; Banat, Ibrahim M.; Sarubbo, Leonie A.

    2016-01-01

    The growing global demand for sustainable technologies that improves the efficiency of petrochemical processes in the oil industry has driven advances in petroleum biotechnology in recent years. Petroleum industry uses substantial amounts of petrochemical-based synthetic surfactants in its activities as mobilizing agents to increase the availability or recovery of hydrocarbons as well as many other applications related to extraction, treatment, cleaning, and transportation. However, biosurfactants have several potential applications for use across the oil processing chain and in the formulations of petrochemical products such as emulsifying/demulsifying agents, anticorrosive, biocides for sulfate-reducing bacteria, fuel formulation, extraction of bitumen from tar sands, and many other innovative applications. Due to their versatility and proven efficiency, biosurfactants are often presented as valuable versatile tools that can transform and modernize petroleum biotechnology in an attempt to provide a true picture of state of the art and directions or use in the oil industry. We believe that biosurfactants are going to have a significant role in many future applications in the oil industries and in this review therefore, we highlight recent important relevant applications, patents disclosures and potential future applications for biosurfactants in petroleum and related industries. PMID:27843439

  17. Lipoprotein Nanoplatform for Targeted Delivery of Diagnostic and Therapeutic Agents

    Directory of Open Access Journals (Sweden)

    Jerry D. Glickson

    2008-03-01

    Full Text Available Low-density lipoprotein (LDL provides a highly versatile natural nanoplatform for delivery of visible or near-infrared fluorescent optical and magnetic resonance imaging (MRI contrast agents and photodynamic therapy and chemotherapeutic agents to normal and neoplastic cells that overexpress low-density lipoprotein receptors (LDLRs. Extension to other lipoproteins ranging in diameter from about 10 nm (high-density lipoprotein [HDL] to over a micron (chylomicrons is feasible. Loading of contrast or therapeutic agents onto or into these particles has been achieved by protein loading (covalent attachment to protein side chains, surface loading (intercalation into the phospholipid monolayer, and core loading (extraction and reconstitution of the triglyceride/cholesterol ester core. Core and surface loading of LDL have been used for delivery of optical imaging agents to tumor cells in vivo and in culture. Surface loading was used for delivery of gadolinium-bis-stearylamide contrast agents for in vivo MRI detection in tumor-bearing mice. Chlorin and phthalocyanine near-infrared photodynamic therapy agents (≤ 400/LDL have been attached by core loading. Protein loading was used to reroute the LDL from its natural receptor (LDLR to folate receptors and could be used to target other receptors. A semisynthetic nanoparticle has been constructed by coating magnetite iron oxide nanoparticles with carboxylated cholesterol and overlaying a monolayer of phospholipid to which apolipoprotein A1 or E was adsorbed for targeting HDL or adsorbing synthetic amphipathic helical peptides ltargeting LDL or folate receptors. These particles can be used for in situ loading of magnetite into cells for MRI-monitored cell tracking or gene expression.

  18. Nutraceuticals as therapeutic agents for atherosclerosis.

    Science.gov (United States)

    Moss, Joe W E; Williams, Jessica O; Ramji, Dipak P

    2018-05-01

    Atherosclerosis, a chronic inflammatory disorder of medium and large arteries and an underlying cause of cardiovascular disease (CVD), is responsible for a third of all global deaths. Current treatments for CVD, such as optimized statin therapy, are associated with considerable residual risk and several side effects in some patients. The outcome of research on the identification of alternative pharmaceutical agents for the treatment of CVD has been relatively disappointing with many promising leads failing at the clinical level. Nutraceuticals, products from food sources with health benefits beyond their nutritional value, represent promising agents in the prevention of CVD or as an add-on therapy with current treatments. This review will highlight the potential of several nutraceuticals, including polyunsaturated fatty acids, flavonoids and other polyphenols, as anti-CVD therapies based on clinical and pre-clinical mechanism-based studies. Copyright © 2018 The Author(s). Published by Elsevier B.V. All rights reserved.

  19. Moral actor, selfish agent.

    Science.gov (United States)

    Frimer, Jeremy A; Schaefer, Nicola K; Oakes, Harrison

    2014-05-01

    People are motivated to behave selfishly while appearing moral. This tension gives rise to 2 divergently motivated selves. The actor-the watched self-tends to be moral; the agent-the self as executor-tends to be selfish. Three studies present direct evidence of the actor's and agent's distinct motives. To recruit the self-as-actor, we asked people to rate the importance of various goals. To recruit the self-as-agent, we asked people to describe their goals verbally. In Study 1, actors claimed their goals were equally about helping the self and others (viz., moral); agents claimed their goals were primarily about helping the self (viz., selfish). This disparity was evident in both individualist and collectivist cultures, attesting to the universality of the selfish agent. Study 2 compared actors' and agents' motives to those of people role-playing highly prosocial or selfish exemplars. In content (Study 2a) and in the impressions they made on an outside observer (Study 2b), actors' motives were similar to those of the prosocial role-players, whereas agents' motives were similar to those of the selfish role-players. Study 3 accounted for the difference between the actor and agent: Participants claimed that their agent's motives were the more realistic and that their actor's motives were the more idealistic. The selfish agent/moral actor duality may account for why implicit and explicit measures of the same construct diverge, and why feeling watched brings out the better angels of human nature.

  20. Effects of Early Chemotherapeutic Treatment on Learning in Adolescent Mice: Implications for Cognitive Impairment and Remediation in Childhood Cancer Survivors

    Science.gov (United States)

    Bisen-Hersh, Emily B.; Hineline, Philip N.; Walker, Ellen A.

    2013-01-01

    Purpose Among children diagnosed with acute lymphoblastic leukemia (ALL) and given chemotherapy-only treatment, 40-70% of survivors experience neurocognitive impairment. The present study used a preclinical mouse model to investigate the effects of early exposure to common ALL chemotherapeutics methotrexate (MTX) and cytarabine (Ara-C) on learning and memory. Experimental Design Pre-weanling mouse pups were treated on postnatal day (PND) 14, 15, and 16 with saline, MTX, Ara-C, or a combination of MTX and Ara-C. Nineteen days following treatment (PND 35), behavioral tasks measuring different aspects of learning and memory were administered. Results Significant impairment in acquisition and retention over both short (1h) and long (24h) intervals, as measured by autoshaping and novel object recognition tasks, were found following treatment with MTX and Ara-C. Similarly, a novel conditional discrimination task revealed impairment in acquisition for chemotherapy-treated mice. No significant group differences were found following the extensive training component of this task, with impairment following the rapid training component occurring only for the highest MTX and Ara-C combination group. Conclusions Findings are consistent with clinical studies suggesting that childhood cancer survivors are slower at learning new information and primarily exhibit deficits in memory years after successful completion of chemotherapy treatment. The occurrence of mild deficits on a novel conditional discrimination task suggests that chemotherapy-induced cognitive impairment may be ameliorated through extensive training or practice. PMID:23596103

  1. Experimental studies on interactions of radiation and cancer chemotherapeutic drugs in normal tissues and a solid tumour

    International Nuclear Information System (INIS)

    Maase, H. van der

    1986-01-01

    The interactions of radiation and seven cancer chemotherapeutic drugs have been investigated in four normal tissues and in a solid C 3 H mouse mammary carcinoma in vivo. The investigated drugs were adriamycin (ADM), bleomycin (BLM), cyclophosphamide (CTX), 5-fluorouracil (5-FU), methotrexate (MTX), mitomycin C (MM-C) and cis-diamminedichloroplatinum(II) (cis-DDP). The drugs enhanced the radiation response in most cases. However, signs of radioprotection was observed for CTX in skin and for MTX in haemopoietic tissue. The interval and the sequence of the two treatment modalities were of utmost importance for the normal tissue reactions. In general, the most serious interactions occurred when drugs were administered simultaneously with or a few hours before radiation. The radiation-modifying effect of the drugs deviated from this pattern in the haemopoietic tissue as the radiation response was most enhanced on drug administration 1-3 days after radiation. Enhancement of the radiation response was generally less pronounced in the tumour model than in the normal tissues. The combined drug-radiation effect was apparently less time-dependent in the tumour than in the normal tissues. (Auth.)

  2. Effects of early chemotherapeutic treatment on learning in adolescent mice: implications for cognitive impairment and remediation in childhood cancer survivors.

    Science.gov (United States)

    Bisen-Hersh, Emily B; Hineline, Philip N; Walker, Ellen A

    2013-06-01

    Among children diagnosed with acute lymphoblastic leukemia (ALL) and given chemotherapy-only treatment, 40% to 70% of survivors experience neurocognitive impairment. The present study used a preclinical mouse model to investigate the effects of early exposure to common ALL chemotherapeutics methotrexate (MTX) and cytarabine (Ara-C) on learning and memory. Preweanling mouse pups were treated on postnatal day (PND) 14, 15, and 16 with saline, MTX, Ara-C, or a combination of MTX and Ara-C. Nineteen days after treatment (PND 35), behavioral tasks measuring different aspects of learning and memory were administered. Significant impairment in acquisition and retention over both short (1 hour) and long (24 hours) intervals, as measured by autoshaping and novel object recognition tasks, was found following treatment with MTX and Ara-C. Similarly, a novel conditional discrimination task revealed impairment in acquisition for chemotherapy-treated mice. No significant group differences were found following the extensive training component of this task, with impairment following the rapid training component occurring only for the highest MTX and Ara-C combination group. Findings are consistent with those from clinical studies suggesting that childhood cancer survivors are slower at learning new information and primarily exhibit deficits in memory years after successful completion of chemotherapy. The occurrence of mild deficits on a novel conditional discrimination task suggests that chemotherapy-induced cognitive impairment may be ameliorated through extensive training or practice. ©2013 AACR

  3. Inhibition of PKCδ reduces cisplatin-induced nephrotoxicity without blocking chemotherapeutic efficacy in mouse models of cancer

    Science.gov (United States)

    Pabla, Navjotsingh; Dong, Guie; Jiang, Man; Huang, Shuang; Kumar, M. Vijay; Messing, Robert O.; Dong, Zheng

    2011-01-01

    Cisplatin is a widely used cancer therapy drug that unfortunately has major side effects in normal tissues, notably nephrotoxicity in kidneys. Despite intensive research, the mechanism of cisplatin-induced nephrotoxicity remains unclear, and renoprotective approaches during cisplatin-based chemotherapy are lacking. Here we have identified PKCδ as a critical regulator of cisplatin nephrotoxicity, which can be effectively targeted for renoprotection during chemotherapy. We showed that early during cisplatin nephrotoxicity, Src interacted with, phosphorylated, and activated PKCδ in mouse kidney lysates. After activation, PKCδ regulated MAPKs, but not p53, to induce renal cell apoptosis. Thus, inhibition of PKCδ pharmacologically or genetically attenuated kidney cell apoptosis and tissue damage, preserving renal function during cisplatin treatment. Conversely, inhibition of PKCδ enhanced cisplatin-induced cell death in multiple cancer cell lines and, remarkably, enhanced the chemotherapeutic effects of cisplatin in several xenograft and syngeneic mouse tumor models while protecting kidneys from nephrotoxicity. Together these results demonstrate a role of PKCδ in cisplatin nephrotoxicity and support targeting PKCδ as an effective strategy for renoprotection during cisplatin-based cancer therapy. PMID:21633170

  4. Cyanobacteria: Promising biocatalysts for sustainable chemical production.

    Science.gov (United States)

    Knoot, Cory J; Ungerer, Justin; Wangikar, Pramod P; Pakrasi, Himadri B

    2018-04-06

    Cyanobacteria are photosynthetic prokaryotes showing great promise as biocatalysts for the direct conversion of CO 2 into fuels, chemicals, and other value-added products. Introduction of just a few heterologous genes can endow cyanobacteria with the ability to transform specific central metabolites into many end products. Recent engineering efforts have centered around harnessing the potential of these microbial biofactories for sustainable production of chemicals conventionally produced from fossil fuels. Here, we present an overview of the unique chemistry that cyanobacteria have been co-opted to perform. We highlight key lessons learned from these engineering efforts and discuss advantages and disadvantages of various approaches. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  5. Analysis of promising sustainable renovation concepts

    DEFF Research Database (Denmark)

    Vanhoutteghem, Lies; Tommerup, Henrik M.; Svendsen, Svend

    This report focuses on analyses of the most promising existing sustainable renovation concepts, i.e. full-service concepts and technical concepts, for single-family houses. As a basis for the analyses a detailed building stock analysis was carried out. Furthermore, as a basis a general working...... method for proposals on package solutions for sustainable renovation was described. The method consists of four steps, going from investigation of the house to proposal for sustainable renovation, detailed planning and commissioning after renovation. It could be used by teams of consultants...... of the building envelope and the electricity required to run the system. Positive impact on the indoor environment can be expected. Thermal comfort will be improved by insulation and air-tightness measures that will increase surface temperatures and reduce draught from e.g. badly insulated windows. A ventilation...

  6. Biomolecular simulations on petascale: promises and challenges

    International Nuclear Information System (INIS)

    Agarwal, Pratul K; Alam, Sadaf R

    2006-01-01

    Proteins work as highly efficient machines at the molecular level and are responsible for a variety of processes in all living cells. There is wide interest in understanding these machines for implications in biochemical/biotechnology industries as well as in health related fields. Over the last century, investigations of proteins based on a variety of experimental techniques have provided a wealth of information. More recently, theoretical and computational modeling using large scale simulations is providing novel insights into the functioning of these machines. The next generation supercomputers with petascale computing power, hold great promises as well as challenges for the biomolecular simulation scientists. We briefly discuss the progress being made in this area

  7. Halopentacenes: Promising Candidates for Organic Semiconductors

    International Nuclear Information System (INIS)

    Gong-He, Du; Zhao-Yu, Ren; Ji-Ming, Zheng; Ping, Guo

    2009-01-01

    We introduce polar substituents such as F, Cl, Br into pentacene to enhance the dissolubility in common organic solvents while retaining the high charge-carrier mobilities of pentacene. Geometric structures, dipole moments, frontier molecule orbits, ionization potentials and electron affinities, as well as reorganization energies of those molecules, and of pentacene for comparison, are successively calculated by density functional theory. The results indicate that halopentacenes have rather small reorganization energies (< 0.2 eV), and when the substituents are in position 2 or positions 2 and 9, they are polarity molecules. Thus we conjecture that they can easily be dissolved in common organic solvents, and are promising candidates for organic semiconductors. (condensed matter: electronicstructure, electrical, magnetic, and opticalproperties)

  8. Underexploited tropical plants with promising economic value

    Energy Technology Data Exchange (ETDEWEB)

    1975-01-01

    The apparent advantages of staple plants over the minor tropical plants often result only from the disproportionate research attention they have been given. A world-wide inquiry resulted in a list of 400 promising but neglected species. The 36 most important species are described in compact monographs and concern cereals (Echinochloa turnerana, grain amaranths, quinua and Zosterea mazina), roots and tubers (Arrachacha, cocoyams and taro), vegetables (chaya, hearts of palms, wax gourd, winged bean), fruits (durian, mangosteen, naranjilla, pejibaye, pummelo, soursop, uvilla), oilseeds (babassu palm, buffalo gourd, Caryocar species, Hessenia polycarpa and jojoba), forage (Acacia albida, Brosimum alicastrum Cassia sturtii, saltbushes and tamarugo) and other crops (buriti palm, Calathea lutea, candelilla, guar, guayule, Paspalum vaginatum, ramie and Spirulina).

  9. Nanomedicine delivers promising treatments for rheumatoid arthritis.

    Science.gov (United States)

    Prasad, Leena Kumari; O'Mary, Hannah; Cui, Zhengrong

    2015-01-01

    An increased understanding in the pathophysiology of chronic inflammatory diseases, such as rheumatoid arthritis, reveals that the diseased tissue and the increased presence of macrophages and other overexpressed molecules within the tissue can be exploited to enhance the delivery of nanomedicine. Nanomedicine can passively accumulate into chronic inflammatory tissues via the enhanced permeability and retention phenomenon, or be surface conjugated with a ligand to actively bind to receptors overexpressed by cells within chronic inflammatory tissues, leading to increased efficacy and reduced systemic side-effects. This review highlights the research conducted over the past decade on using nanomedicine for potential treatment of rheumatoid arthritis and summarizes some of the major findings and promising opportunities on using nanomedicine to treat this prevalent and chronic disease.

  10. Agent Architectures for Compliance

    Science.gov (United States)

    Burgemeestre, Brigitte; Hulstijn, Joris; Tan, Yao-Hua

    A Normative Multi-Agent System consists of autonomous agents who must comply with social norms. Different kinds of norms make different assumptions about the cognitive architecture of the agents. For example, a principle-based norm assumes that agents can reflect upon the consequences of their actions; a rule-based formulation only assumes that agents can avoid violations. In this paper we present several cognitive agent architectures for self-monitoring and compliance. We show how different assumptions about the cognitive architecture lead to different information needs when assessing compliance. The approach is validated with a case study of horizontal monitoring, an approach to corporate tax auditing recently introduced by the Dutch Customs and Tax Authority.

  11. Stabilized radiographic scanning agents

    International Nuclear Information System (INIS)

    Fawzi, M.B.

    1982-01-01

    Stable compositions useful as technetium 99m-based scintigraphic agents comprise gentisic acid or a pharmaceutically-acceptable salt or ester thereof in combination with a pertechnetate reducing agent or dissolved in pertechnetate-99m (sup(99m)TcOsub(4)sup(-)) solution. The compositions are especially useful in combination with a phosphate or phosphonate material that carries the radionuclide to bone, thus providing a skeletal imaging agent

  12. Contrast agents for MRI

    International Nuclear Information System (INIS)

    Bonnemain, B.

    1994-01-01

    Contrast agents MRI (Magnetic Resonance Imaging) have been developed to improve the diagnostic information obtained by this technic. They mainly interact on T1 and T2 parameters and increase consequently normal to abnormal tissues contrast. The paramagnetic agents which mainly act on longitudinal relaxation rate (T1) are gadolinium complexes for which stability is the main parameter to avoid any release of free gadolinium. The superparamagnetic agents that decrease signal intensity by an effect on transversal relaxation rate (T2) are developed for liver, digestive and lymph node imaging. Many area of research are now opened for optimal use of present and future contrast agents in MRI. (author). 28 refs., 4 tabs

  13. Decontamination Data - Blister Agents

    Data.gov (United States)

    U.S. Environmental Protection Agency — Decontamination efficacy data for blister agents on various building materials using various decontamination solutions. This dataset is associated with the following...

  14. Magnetic hydroxyapatite: a promising multifunctional platform for nanomedicine application

    Science.gov (United States)

    Mondal, Sudip; Manivasagan, Panchanathan; Bharathiraja, Subramaniyan; Santha Moorthy, Madhappan; Kim, Hye Hyun; Seo, Hansu; Lee, Kang Dae; Oh, Junghwan

    2017-01-01

    In this review, specific attention is paid to the development of nanostructured magnetic hydroxyapatite (MHAp) and its potential application in controlled drug/gene delivery, tissue engineering, magnetic hyperthermia treatment, and the development of contrast agents for magnetic resonance imaging. Both magnetite and hydroxyapatite materials have excellent prospects in nanomedicine with multifunctional therapeutic approaches. To date, many research articles have focused on biomedical applications of nanomaterials because of which it is very difficult to focus on any particular type of nanomaterial. This study is possibly the first effort to emphasize on the comprehensive assessment of MHAp nanostructures for biomedical applications supported with very recent experimental studies. From basic concepts to the real-life applications, the relevant characteristics of magnetic biomaterials are patented which are briefly discussed. The potential therapeutic and diagnostic ability of MHAp-nanostructured materials make them an ideal platform for future nanomedicine. We hope that this advanced review will provide a better understanding of MHAp and its important features to utilize it as a promising material for multifunctional biomedical applications. PMID:29200851

  15. Cannabis and endocannabinoid modulators: Therapeutic promises and challenges

    Science.gov (United States)

    Grant, Igor; Cahn, B. Rael

    2008-01-01

    The discovery that botanical cannabinoids such as delta-9 tetrahydrocannabinol exert some of their effect through binding specific cannabinoid receptor sites has led to the discovery of an endocannabinoid signaling system, which in turn has spurred research into the mechanisms of action and addiction potential of cannabis on the one hand, while opening the possibility of developing novel therapeutic agents on the other. This paper reviews current understanding of CB1, CB2, and other possible cannabinoid receptors, their arachidonic acid derived ligands (e.g. anandamide; 2 arachidonoyl glycerol), and their possible physiological roles. CB1 is heavily represented in the central nervous system, but is found in other tissues as well; CB2 tends to be localized to immune cells. Activation of the endocannabinoid system can result in enhanced or dampened activity in various neural circuits depending on their own state of activation. This suggests that one function of the endocannabinoid system may be to maintain steady state. The therapeutic action of botanical cannabis or of synthetic molecules that are agonists, antagonists, or which may otherwise modify endocannabinoid metabolism and activity indicates they may have promise as neuroprotectants, and may be of value in the treatment of certain types of pain, epilepsy, spasticity, eating disorders, inflammation, and possibly blood pressure control. PMID:18806886

  16. Microencapsulation: A promising technique for controlled drug delivery.

    Science.gov (United States)

    Singh, M N; Hemant, K S Y; Ram, M; Shivakumar, H G

    2010-07-01

    MICROPARTICLES OFFER VARIOUS SIGNIFICANT ADVANTAGES AS DRUG DELIVERY SYSTEMS, INCLUDING: (i) an effective protection of the encapsulated active agent against (e.g. enzymatic) degradation, (ii) the possibility to accurately control the release rate of the incorporated drug over periods of hours to months, (iii) an easy administration (compared to alternative parenteral controlled release dosage forms, such as macro-sized implants), and (iv) Desired, pre-programmed drug release profiles can be provided which match the therapeutic needs of the patient. This article gives an overview on the general aspects and recent advances in drug-loaded microparticles to improve the efficiency of various medical treatments. An appropriately designed controlled release drug delivery system can be a foot ahead towards solving problems concerning to the targeting of drug to a specific organ or tissue, and controlling the rate of drug delivery to the target site. The development of oral controlled release systems has been a challenge to formulation scientist due to their inability to restrain and localize the system at targeted areas of gastrointestinal tract. Microparticulate drug delivery systems are an interesting and promising option when developing an oral controlled release system. The objective of this paper is to take a closer look at microparticles as drug delivery devices for increasing efficiency of drug delivery, improving the release profile and drug targeting. In order to appreciate the application possibilities of microcapsules in drug delivery, some fundamental aspects are briefly reviewed.

  17. Magnetic hydroxyapatite: a promising multifunctional platform for nanomedicine application.

    Science.gov (United States)

    Mondal, Sudip; Manivasagan, Panchanathan; Bharathiraja, Subramaniyan; Santha Moorthy, Madhappan; Kim, Hye Hyun; Seo, Hansu; Lee, Kang Dae; Oh, Junghwan

    2017-01-01

    In this review, specific attention is paid to the development of nanostructured magnetic hydroxyapatite (MHAp) and its potential application in controlled drug/gene delivery, tissue engineering, magnetic hyperthermia treatment, and the development of contrast agents for magnetic resonance imaging. Both magnetite and hydroxyapatite materials have excellent prospects in nanomedicine with multifunctional therapeutic approaches. To date, many research articles have focused on biomedical applications of nanomaterials because of which it is very difficult to focus on any particular type of nanomaterial. This study is possibly the first effort to emphasize on the comprehensive assessment of MHAp nanostructures for biomedical applications supported with very recent experimental studies. From basic concepts to the real-life applications, the relevant characteristics of magnetic biomaterials are patented which are briefly discussed. The potential therapeutic and diagnostic ability of MHAp-nanostructured materials make them an ideal platform for future nanomedicine. We hope that this advanced review will provide a better understanding of MHAp and its important features to utilize it as a promising material for multifunctional biomedical applications.

  18. Volatile aldehydes are promising broad-spectrum postharvest insecticides.

    Science.gov (United States)

    Hammond, D G; Rangel, S; Kubo, I

    2000-09-01

    A variety of naturally occurring aldehydes common in plants have been evaluated for their insecticidal activity and for phytotoxicity to postharvest fruits, vegetables, and grains. Twenty-nine compounds were initially screened for their activity against aphids on fava bean leaf disks. Application under reduced pressure (partial vacuum) for the first quarter of fumigation increased insecticidal activity severalfold. The 11 best aldehydes were assayed against aphids placed under the third leaf of whole heads of iceberg lettuce using the same two-tier reduced-pressure regime, which caused no additional detriment to the commodity over fumigation at atmospheric pressure. Phytotoxicity to naked and wrapped iceburg lettuce, green and red table grapes, lemon, grapefruit, orange, broccoli, avocado, cabbage, pinto bean, and rice at doses that killed 100% of aphids was recorded for three promising fumigants: propanal, (E)-2-pentenal, and 2-methyl-(E)-2-butenal. These three compounds have excellent potential as affordable postharvest insect control agents, killing 100% of the aphids with little or no detectable harm to a majority of the commodities tested. Preliminary assays indicate that similar doses are also effective against mealybugs, thrips, and whitefly.

  19. The promise of Lean in health care.

    Science.gov (United States)

    Toussaint, John S; Berry, Leonard L

    2013-01-01

    An urgent need in American health care is improving quality and efficiency while controlling costs. One promising management approach implemented by some leading health care institutions is Lean, a quality improvement philosophy and set of principles originated by the Toyota Motor Company. Health care cases reveal that Lean is as applicable in complex knowledge work as it is in assembly-line manufacturing. When well executed, Lean transforms how an organization works and creates an insatiable quest for improvement. In this article, we define Lean and present 6 principles that constitute the essential dynamic of Lean management: attitude of continuous improvement, value creation, unity of purpose, respect for front-line workers, visual tracking, and flexible regimentation. Health care case studies illustrate each principle. The goal of this article is to provide a template for health care leaders to use in considering the implementation of the Lean management system or in assessing the current state of implementation in their organizations. Copyright © 2013 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  20. Hyperthermia: Clinical promise and current challenges

    International Nuclear Information System (INIS)

    Kapp, D.S.

    1987-01-01

    Local-regional hyperthermia (HT) when used in conjunction with radiation therapy (XRT), has been shown in numerous clinical trials to result in considerable improvement in response rates and local tumor control rates when compared with treatment by XRT alone. Although considerable progress has been made in understanding the biological basis for hyperthermia induced cytotoxicity and radiosensitization, additional research remains in establishing the optimal treatment schedules for the clinical utilization of HT-XRT. The number of HT treatments; the sequencing of HT and XRT; the frequency of administration of HT; and the ideal temperature-time parameters all remain to be better defined for the clinical setting. The role of tumor blood flow on the thermal distributions also warrants further investigation. In addition, considerable effort is needed to improve hyperthermia equipment in order to provide more uniform therapeutic temperature distributions (temperatures ≥42.5%C). Better heating equipment is particularly needed for the treatment of deep seeted tumors. Pertinent clinical literature will be presented summarizing the clinical promise of hyperthermia and the above mentioned clinical challenges

  1. Uterine transplantation: a promising surrogate to surrogacy?

    Science.gov (United States)

    Grynberg, Michael; Ayoubi, Jean-Marc; Bulletti, Carlo; Frydman, Rene; Fanchin, Renato

    2011-03-01

    Infertility due to the inability of the uterus to carry a pregnancy ranks among the most unresolved issues in reproductive medicine. It affects millions of women worldwide who have congenital or acquired uterine affections, often requiring hysterectomy, and potentially represents a considerable fraction of the general infertile population. Patients suffering from severe uterine infertility are currently compelled to go through gestational surrogacy or adoption; both approaches, unfortunately, deprive them of the maternal experience of pregnancy and birth. Uterine transplantation represents an outstanding, yet complex, perspective to alleviating definitive uterine infertility. In the past decades, a number of scientific experiments conducted both in animals and women, focusing on uterine transplantation, have led to promising results. Collectively, these findings undoubtedly constitute a sound basis to clinically apply uterine transplantation in the near future. This paper is, however, an overview not only of the extent and limitations of accumulated scientific knowledge on uterine transplantation, but also its ethical implications, in an effort to define the actual place of such an approach among the therapeutic arsenal for alleviating infertility. © 2011 New York Academy of Sciences.

  2. Medical big data: promise and challenges

    Directory of Open Access Journals (Sweden)

    Choong Ho Lee

    2017-03-01

    Full Text Available The concept of big data, commonly characterized by volume, variety, velocity, and veracity, goes far beyond the data type and includes the aspects of data analysis, such as hypothesis-generating, rather than hypothesis-testing. Big data focuses on temporal stability of the association, rather than on causal relationship and underlying probability distribution assumptions are frequently not required. Medical big data as material to be analyzed has various features that are not only distinct from big data of other disciplines, but also distinct from traditional clinical epidemiology. Big data technology has many areas of application in healthcare, such as predictive modeling and clinical decision support, disease or safety surveillance, public health, and research. Big data analytics frequently exploits analytic methods developed in data mining, including classification, clustering, and regression. Medical big data analyses are complicated by many technical issues, such as missing values, curse of dimensionality, and bias control, and share the inherent limitations of observation study, namely the inability to test causality resulting from residual confounding and reverse causation. Recently, propensity score analysis and instrumental variable analysis have been introduced to overcome these limitations, and they have accomplished a great deal. Many challenges, such as the absence of evidence of practical benefits of big data, methodological issues including legal and ethical issues, and clinical integration and utility issues, must be overcome to realize the promise of medical big data as the fuel of a continuous learning healthcare system that will improve patient outcome and reduce waste in areas including nephrology.

  3. Candida Biofilms: Threats, Challenges, and Promising Strategies

    Science.gov (United States)

    Cavalheiro, Mafalda; Teixeira, Miguel Cacho

    2018-01-01

    Candida species are fungal pathogens known for their ability to cause superficial and systemic infections in the human host. These pathogens are able to persist inside the host due to the development of pathogenicity and multidrug resistance traits, often leading to the failure of therapeutic strategies. One specific feature of Candida species pathogenicity is their ability to form biofilms, which protects them from external factors such as host immune system defenses and antifungal drugs. This review focuses on the current threats and challenges when dealing with biofilms formed by Candida albicans, Candida glabrata, Candida tropicalis, and Candida parapsilosis, highlighting the differences between the four species. Biofilm characteristics depend on the ability of each species to produce extracellular polymeric substances (EPS) and display dimorphic growth, but also on the biofilm substratum, carbon source availability and other factors. Additionally, the transcriptional control over processes like adhesion, biofilm formation, filamentation, and EPS production displays great complexity and diversity within pathogenic yeasts of the Candida genus. These differences not only have implications in the persistence of colonization and infections but also on antifungal resistance typically found in Candida biofilm cells, potentiated by EPS, that functions as a barrier to drug diffusion, and by the overexpression of drug resistance transporters. The ability to interact with different species in in vivo Candida biofilms is also a key factor to consider when dealing with this problem. Despite many challenges, the most promising strategies that are currently available or under development to limit biofilm formation or to eradicate mature biofilms are discussed. PMID:29487851

  4. Artificial Intelligence in Surgery: Promises and Perils.

    Science.gov (United States)

    Hashimoto, Daniel A; Rosman, Guy; Rus, Daniela; Meireles, Ozanan R

    2018-07-01

    The aim of this review was to summarize major topics in artificial intelligence (AI), including their applications and limitations in surgery. This paper reviews the key capabilities of AI to help surgeons understand and critically evaluate new AI applications and to contribute to new developments. AI is composed of various subfields that each provide potential solutions to clinical problems. Each of the core subfields of AI reviewed in this piece has also been used in other industries such as the autonomous car, social networks, and deep learning computers. A review of AI papers across computer science, statistics, and medical sources was conducted to identify key concepts and techniques within AI that are driving innovation across industries, including surgery. Limitations and challenges of working with AI were also reviewed. Four main subfields of AI were defined: (1) machine learning, (2) artificial neural networks, (3) natural language processing, and (4) computer vision. Their current and future applications to surgical practice were introduced, including big data analytics and clinical decision support systems. The implications of AI for surgeons and the role of surgeons in advancing the technology to optimize clinical effectiveness were discussed. Surgeons are well positioned to help integrate AI into modern practice. Surgeons should partner with data scientists to capture data across phases of care and to provide clinical context, for AI has the potential to revolutionize the way surgery is taught and practiced with the promise of a future optimized for the highest quality patient care.

  5. Candida Biofilms: Threats, Challenges, and Promising Strategies.

    Science.gov (United States)

    Cavalheiro, Mafalda; Teixeira, Miguel Cacho

    2018-01-01

    Candida species are fungal pathogens known for their ability to cause superficial and systemic infections in the human host. These pathogens are able to persist inside the host due to the development of pathogenicity and multidrug resistance traits, often leading to the failure of therapeutic strategies. One specific feature of Candida species pathogenicity is their ability to form biofilms, which protects them from external factors such as host immune system defenses and antifungal drugs. This review focuses on the current threats and challenges when dealing with biofilms formed by Candida albicans, Candida glabrata, Candida tropicalis , and Candida parapsilosis , highlighting the differences between the four species. Biofilm characteristics depend on the ability of each species to produce extracellular polymeric substances (EPS) and display dimorphic growth, but also on the biofilm substratum, carbon source availability and other factors. Additionally, the transcriptional control over processes like adhesion, biofilm formation, filamentation, and EPS production displays great complexity and diversity within pathogenic yeasts of the Candida genus. These differences not only have implications in the persistence of colonization and infections but also on antifungal resistance typically found in Candida biofilm cells, potentiated by EPS, that functions as a barrier to drug diffusion, and by the overexpression of drug resistance transporters. The ability to interact with different species in in vivo Candida biofilms is also a key factor to consider when dealing with this problem. Despite many challenges, the most promising strategies that are currently available or under development to limit biofilm formation or to eradicate mature biofilms are discussed.

  6. Medical big data: promise and challenges.

    Science.gov (United States)

    Lee, Choong Ho; Yoon, Hyung-Jin

    2017-03-01

    The concept of big data, commonly characterized by volume, variety, velocity, and veracity, goes far beyond the data type and includes the aspects of data analysis, such as hypothesis-generating, rather than hypothesis-testing. Big data focuses on temporal stability of the association, rather than on causal relationship and underlying probability distribution assumptions are frequently not required. Medical big data as material to be analyzed has various features that are not only distinct from big data of other disciplines, but also distinct from traditional clinical epidemiology. Big data technology has many areas of application in healthcare, such as predictive modeling and clinical decision support, disease or safety surveillance, public health, and research. Big data analytics frequently exploits analytic methods developed in data mining, including classification, clustering, and regression. Medical big data analyses are complicated by many technical issues, such as missing values, curse of dimensionality, and bias control, and share the inherent limitations of observation study, namely the inability to test causality resulting from residual confounding and reverse causation. Recently, propensity score analysis and instrumental variable analysis have been introduced to overcome these limitations, and they have accomplished a great deal. Many challenges, such as the absence of evidence of practical benefits of big data, methodological issues including legal and ethical issues, and clinical integration and utility issues, must be overcome to realize the promise of medical big data as the fuel of a continuous learning healthcare system that will improve patient outcome and reduce waste in areas including nephrology.

  7. Epigenetic Pathways of Oncogenic Viruses: Therapeutic Promises.

    Science.gov (United States)

    El-Araby, Amr M; Fouad, Abdelrahman A; Hanbal, Amr M; Abdelwahab, Sara M; Qassem, Omar M; El-Araby, Moustafa E

    2016-02-01

    Cancerous transformation comprises different events that are both genetic and epigenetic. The ultimate goal for such events is to maintain cell survival and proliferation. This transformation occurs as a consequence of different features such as environmental and genetic factors, as well as some types of infection. Many viral infections are considered to be causative agents of a number of different malignancies. To convert normal cells into cancerous cells, oncogenic viruses must function at the epigenetic level to communicate with their host cells. Oncogenic viruses encode certain epigenetic factors that lead to the immortality and proliferation of infected cells. The epigenetic effectors produced by oncogenic viruses constitute appealing targets to prevent and treat malignant diseases caused by these viruses. In this review, we highlight the importance of epigenetic reprogramming for virus-induced oncogenesis, with special emphasis on viral epigenetic oncoproteins as therapeutic targets. The discovery of molecular components that target epigenetic pathways, especially viral factors, is also discussed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. UVA1 a promising approach for scleroderma

    Science.gov (United States)

    Keyal, Uma; Bhatta, Anil Kumar; Wang, Xiu Li

    2017-01-01

    Scleroderma is a complex connective tissue disease characterized by fibrosis, vasculopathy, and immune system dysfunction. The heterogeneity of disease presentation and poorly understood etiology has made the management of scleroderma difficult. The available treatment options like immunosuppressive agents are associated with potentially hazardous side effects and physiotherapy, which to a certain degree helps to minimize the loss of function in digits and limbs, has only limited success. Also, studies investigating antifibrotic therapies have failed to report any significant improvement. Hence, there is currently no effective therapy for scleroderma. Recently, phototherapy has been extensively studied and found to be effective in treating scleroderma. Initially psoralen + ultraviolet A (PUVA) significantly enriched the therapeutic panel, but more recently ultraviolet A1 (UVA1) is seen to replace PUVA therapy. This might be because of UVA1 therapy being free of side effects seen with psoralens such as nausea, vomiting or photokeratitis. In addition, UVA1 is seen to lower risk of phototoxic reactions with deeper penetration of radiation. The present review will put some light on the use of UVA1 for treating cutaneous lesion in scleroderma and we aim to find the most benefitted group of patients and most effective dose of UVA1 for different types of scleroderma. PMID:28979701

  9. Promising therapies for treatment of nonalcoholic steatohepatitis

    Science.gov (United States)

    Noureddin, Mazen; Zhang, Alice; Loomba, Rohit

    2018-01-01

    Introduction Non-alcoholic fatty liver disease (NAFLD) has become the most common etiology for abnormal aminotransferase levels and chronic liver disease. Its growing prevalence is largely linked to the presence of metabolic syndrome, particularly diabetes and insulin resistance. It is estimated that 60–80% of the type 2 diabetic population has NAFLD. NAFLD encompasses a range of conditions ranging from simple steatosis to nonalcoholic steatohepatitis (NASH). A subset of patients with hepatic steatosis progress to NASH, while 15–20% of patients with NASH develop cirrhosis. This progression is thought to be multifactorial, and there are currently no FDA-approved medications for the treatment of NASH. Areas covered We review drugs currently in Phase II and III clinical trials for treatment of NAFLD and NASH, including their mechanisms of action, relationship to the pathophysiology of NASH, and rationale for their development. Expert opinion The treatment of NASH is complex and necessitates targeting a number of different pathways. Combination therapy, preferably tailored toward the disease stage and severity, will be needed to achieve maximum therapeutic effect. With multiple agents currently being developed, there may soon be an ability to effectively slow or even reverse the disease process in many NAFLD/NASH patients. PMID:27501374

  10. Evaluation of silymarin as a promising radioprotector

    Energy Technology Data Exchange (ETDEWEB)

    Adhikari, Manish; Chawla, Raman [Institute of Nuclear Medicine and Allied Sciences, Delhi (India); Arora, Rajesh [Institute of Nuclear Medicine and Allied Sciences, Delhi (India); Trakia Univ., Stara Zagora (BG). Dept. of Chemistry and Biochemistry] (and others)

    2010-05-15

    Silymarin, a purified extract of seeds of Silybum marianum L. and well known for its hepatoprotective abilities, has been evaluated for inherent utility as a radioprotective agent. A fraction (INM-7035) was authenticated by characterizing the percentage composition of silybin A and B (39.9% and 57.4%). Free radical scavenging activities of INM-7035 against superoxide radicals (>68%), hydroxyl radicals (>33.75%), DPPH (67.2%), and ABTS (32.4%) were also evaluated. The fraction chelated (>30%) ferrous ions, thereby able to restrict amplification. INM-7035 exhibited >50% peroxyl radical scavenging activity in the lipid phase along with dose-dependent (R{sup 2} = 0.990) reducing power in the aqueous phase. Radiation-induced free radical flux can lead to disruption of biomolecules like membrane lipids. INM-7035 completely inhibited lipid peroxidative stress in case of membranes against supralethal radiation stress in the liposomal system. The ability of INM-7035 to modulate the levels of NF-{kappa}B, indicated its inherent potential as a radioprotective bioactive constituent. (orig.)

  11. Change Agent Survival Guide

    Science.gov (United States)

    Dunbar, Folwell L.

    2011-01-01

    Consulting is a rough racket. Only a tarantula hair above IRS agents, meter maids and used car sales people, the profession is a prickly burr for slings and arrows. Throw in education, focus on dysfunctional schools and call oneself a "change agent," and this bad rap all but disappears. Unfortunately, though, consulting/coaching/mentoring in…

  12. Teaching Tourism Change Agents

    DEFF Research Database (Denmark)

    Stilling Blichfeldt, Bodil; Kvistgaard, Hans-Peter; Hird, John

    2017-01-01

    course that is part of a Tourism Master’s program, where a major challenge is not only to teach students about change and change agents, but to teach them how change feels and ho w to become change agents. The c hange management course contains an experiment inspired by experiential teaching literature...... change in tourism in the future....

  13. Travel Agent Course Outline.

    Science.gov (United States)

    British Columbia Dept. of Education, Victoria.

    Written for college entry-level travel agent training courses, this course outline can also be used for inservice training programs offered by travel agencies. The outline provides information on the work of a travel agent and gives clear statements on what learners must be able to do by the end of their training. Material is divided into eight…

  14. Radiographic scintiscanning agent

    International Nuclear Information System (INIS)

    Bevan, J.A.

    1979-01-01

    A new technetium-based scintiscanning agent has been prepared comprising a water soluble sup(99m)Tc-methanehydroxydiphosphonate in combination with a reducing agent selected from stannous, ferrous, chromous and titanous salts. As an additional stabilizer salts and esters of gentisic or ascorbic acids have been used. (E.G.)

  15. Radiographic scanning agent

    International Nuclear Information System (INIS)

    Tofe, A.J.

    1976-01-01

    A stable radiographic scanning agent on a sup(99m)Tc basis has been developed. The substance contains a pertechnetate reduction agent, tin(II)-chloride, chromium(II)-chloride, or iron(II)-sulphate, as well as an organospecific carrier and ascorbic acid or a pharmacologically admissible salt or ester of ascorbic acid. (VJ) [de

  16. Stable radiographic scanning agents

    International Nuclear Information System (INIS)

    1976-01-01

    Stable compositions which are useful in the preparation of Technetium-99m-based scintigraphic agents are discussed. They are comprised of ascorbic acid or a pharmaceutically acceptable salt or ester thereof in combination with a pertechnetate reducing agent or dissolved in oxidized pertechnetate-99m (sup(99m)TcO 4 - ) solution

  17. Strategy for chemotherapeutic delivery using a nanosized porous metal-organic framework with a central composite design.

    Science.gov (United States)

    Li, Yingpeng; Li, Xiuyan; Guan, Qingxia; Zhang, Chunjing; Xu, Ting; Dong, Yujing; Bai, Xinyu; Zhang, Weiping

    2017-01-01

    Enhancing drug delivery is an ongoing endeavor in pharmaceutics, especially when the efficacy of chemotherapy for cancer is concerned. In this study, we prepared and evaluated nanosized HKUST-1 (nanoHKUST-1), nanosized metal-organic drug delivery framework, loaded with 5-fluorouracil (5-FU) for potential use in cancer treatment. NanoHKUST-1 was prepared by reacting copper (II) acetate [Cu(OAc) 2 ] and benzene-1,3,5-tricarboxylic acid (H 3 BTC) with benzoic acid (C 6 H 5 COOH) at room temperature (23.7°C±2.4°C). A central composite design was used to optimize 5-FU-loaded nanoHKUST-1. Contact time, ethanol concentration, and 5-FU:material ratios were the independent variables, and the entrapment efficiency of 5-FU was the response parameter measured. Powder X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and nitrogen adsorption were used to determine the morphology of nanoHKUST-1. In addition, 5-FU release studies were conducted, and the in vitro cytotoxicity was evaluated. Entrapment efficiency and drug loading were 9.96% and 40.22%, respectively, while the small-angle X-ray diffraction patterns confirmed a regular porous structure. The SEM and TEM images of the nanoHKUST-1 confirmed the presence of round particles (diameter: approximately 100 nm) and regular polygon arrays of mesoporous channels of approximately 2-5 nm. The half-maximal lethal concentration (LC 50 ) of the 5-FU-loaded nanoHKUST-1 was approximately 10 µg/mL. The results indicated that nanoHKUST-1 is a potential vector worth developing as a cancer chemotherapeutic drug delivery system.

  18. Integrity protection for code-on-demand mobile agents in e-commerce

    OpenAIRE

    Wang, TH; Guan, SU; Chan, TK

    2002-01-01

    The mobile agent paradigm has been proposed as a promising solution to facilitate distributed computing over open and heterogeneous networks. Mobility, autonomy, and intelligence are identified as key features of mobile agent systems and enabling characteristics for the next-generation smart electronic commerce on the Internet. However, security-related issues, especially integrity protection in mobile agent technology, still hinder the widespread use of software agents: from the agent’s pers...

  19. The promise of innovation: Nuclear energy horizons

    International Nuclear Information System (INIS)

    Mourogov, V.

    2003-01-01

    The 21st century promises the most open, competitive, and globalized markets in human history, as well as the most rapid pace of technological change ever. For nuclear energy, as any other, that presents challenges. Though the atom now supplies a good share of world electricity, its share of total energy is relatively small, anywhere from four to six per cent depending on how it is calculated. And, while energy is most needed in the developing world, four of every five nuclear plants are in industrialized countries. Critical problems that need to be overcome are well known - high capital costs for new plants, and concerns over proliferation risks and safety, (including safety of waste disposal) stand high among them. The IAEA and other programmes are confronting these problems through ambitious initiatives involving both industrialized and developing countries. They include the collaborative efforts known as the Generation-IV International Forum (GIF) and the IAEA International Project on Innovative Nuclear Reactors and Fuel Cycles (INPRO). They use ideas, results and the best experiences from today's research and development tools and advanced types of nuclear energy systems to meet tomorrow's challenges. Though the market often decides the fate of new initiatives, the market is not always right for the common good. Governments, and the people that influence them, play an indispensable role in shaping progress in energy fields for rich and poor countries alike. They shoulder the main responsibilities for fundamental science, basic research, and long-term investments. For energy in particular, government investment and support will prove instrumental in the pace of innovation toward long-term options that are ready to replace limited fossil fuel supplies, and respond to the growing premium put on clean energy alternatives. Yet governments cannot go it alone. The challenges are too diverse and complex, and public concerns - about proliferation or safety - go beyond

  20. The epigenetic promise for prostate cancer diagnosis.

    Science.gov (United States)

    Van Neste, Leander; Herman, James G; Otto, Gaëtan; Bigley, Joseph W; Epstein, Jonathan I; Van Criekinge, Wim

    2012-08-01

    Prostate cancer is the most common cancer diagnosis in men and a leading cause of death. Improvements in disease management would have a significant impact and could be facilitated by the development of biomarkers, whether for diagnostic, prognostic, or predictive purposes. The blood-based prostate biomarker PSA has been part of clinical practice for over two decades, although it is surrounded by controversy. While debates of usefulness are ongoing, alternatives should be explored. Particularly with recent recommendations against routine PSA-testing, the time is ripe to explore promising biomarkers to yield a more efficient and accurate screening for detection and management of prostate cancer. Epigenetic changes, more specifically DNA methylation, are amongst the most common alterations in human cancer. These changes are associated with transcriptional silencing of genes, leading to an altered cellular biology. One gene in particular, GSTP1, has been widely studied in prostate cancer. Therefore a meta-analysis has been conducted to examine the role of this and other genes and the potential contribution to prostate cancer management and screening refinement. More than 30 independent, peer reviewed studies have reported a consistently high sensitivity and specificity of GSTP1 hypermethylation in prostatectomy or biopsy tissue. The meta-analysis combined and compared these results. GSTP1 methylation detection can serve an important role in prostate cancer managment. The meta-analysis clearly confirmed a link between tissue DNA hypermethylation of this and other genes and prostate cancer. Detection of DNA methylation in genes, including GSTP1, could serve an important role in clinical practice. Copyright © 2011 Wiley Periodicals, Inc.

  1. Candida Biofilms: Threats, Challenges, and Promising Strategies

    Directory of Open Access Journals (Sweden)

    Mafalda Cavalheiro

    2018-02-01

    Full Text Available Candida species are fungal pathogens known for their ability to cause superficial and systemic infections in the human host. These pathogens are able to persist inside the host due to the development of pathogenicity and multidrug resistance traits, often leading to the failure of therapeutic strategies. One specific feature of Candida species pathogenicity is their ability to form biofilms, which protects them from external factors such as host immune system defenses and antifungal drugs. This review focuses on the current threats and challenges when dealing with biofilms formed by Candida albicans, Candida glabrata, Candida tropicalis, and Candida parapsilosis, highlighting the differences between the four species. Biofilm characteristics depend on the ability of each species to produce extracellular polymeric substances (EPS and display dimorphic growth, but also on the biofilm substratum, carbon source availability and other factors. Additionally, the transcriptional control over processes like adhesion, biofilm formation, filamentation, and EPS production displays great complexity and diversity within pathogenic yeasts of the Candida genus. These differences not only have implications in the persistence of colonization and infections but also on antifungal resistance typically found in Candida biofilm cells, potentiated by EPS, that functions as a barrier to drug diffusion, and by the overexpression of drug resistance transporters. The ability to interact with different species in in vivo Candida biofilms is also a key factor to consider when dealing with this problem. Despite many challenges, the most promising strategies that are currently available or under development to limit biofilm formation or to eradicate mature biofilms are discussed.

  2. Enantioselectivity of mass spectrometry: challenges and promises.

    Science.gov (United States)

    Awad, Hanan; El-Aneed, Anas

    2013-01-01

    With the fast growing market of pure enantiomer drugs and bioactive molecules, new chiral-selective analytical tools have been instigated including the use of mass spectrometry (MS). Even though MS is one of the best analytical tools that has efficiently been used in several pharmaceutical and biological applications, traditionally MS is considered as a "chiral-blind" technique. This limitation is due to the MS inability to differentiate between two enantiomers of a chiral molecule based merely on their masses. Several approaches have been explored to assess the potential role of MS in chiral analysis. The first approach depends on the use of MS-hyphenated techniques utilizing fast and sensitive chiral separation tools such as liquid chromatography (LC), gas chromatography (GC), and capillary electrophoresis (CE) coupled to MS detector. More recently, several alternative separation techniques have been evaluated such as supercritical fluid chromatography (SFC) and capillary electrochromatography (CEC); the latter being a hybrid technique that combines the efficiency of CE with the selectivity of LC. The second approach is based on using the MS instrument solely for the chiral recognition. This method depends on the behavioral differences between enantiomers towards a foreign molecule and the ability of MS to monitor such differences. These behavioral differences can be divided into three types: (i) differences in the enantiomeric affinity for association with the chiral selector, (ii) differences of the enantiomeric exchange rate with a foreign reagent, and (iii) differences in the complex MS dissociation behaviors of the enantiomers. Most recently, ion mobility spectrometry was introduced to qualitatively and quantitatively evaluate chiral compounds. This article provides an overview of MS role in chiral analysis by discussing MS based methodologies and presenting the challenges and promises associated with each approach. © 2013 Wiley Periodicals, Inc.

  3. Enhancing E-Learning through Web Service and Intelligent Agents

    Directory of Open Access Journals (Sweden)

    Nasir Hussain

    2006-04-01

    Full Text Available E-learning is basically the integration of various technologies. E-Learning technology is now maturing and we can find a multiplicity of standards. New technologies such as agents and web services are promising better results. In this paper we have proposed an e-learning architecture that is dependent on intelligent agent systems and web services. These communication technologies will make the architecture more robust, scalable and efficient.

  4. Invariance and universality in social agent-based simulations

    Science.gov (United States)

    Cioffi-Revilla, Claudio

    2002-01-01

    Agent-based simulation models have a promising future in the social sciences, from political science to anthropology, economics, and sociology. To realize their full scientific potential, however, these models must address a set of key problems, such as the number of interacting agents and their geometry, network topology, time calibration, phenomenological calibration, structural stability, power laws, and other substantive and methodological issues. This paper discusses and highlights these problems and outlines some solutions. PMID:12011412

  5. Agent Programming Languages and Logics in Agent-Based Simulation

    DEFF Research Database (Denmark)

    Larsen, John

    2018-01-01

    and social behavior, and work on verification. Agent-based simulation is an approach for simulation that also uses the notion of agents. Although agent programming languages and logics are much less used in agent-based simulation, there are successful examples with agents designed according to the BDI...

  6. Biological warfare agents

    Directory of Open Access Journals (Sweden)

    Duraipandian Thavaselvam

    2010-01-01

    Full Text Available The recent bioterrorist attacks using anthrax spores have emphasized the need to detect and decontaminate critical facilities in the shortest possible time. There has been a remarkable progress in the detection, protection and decontamination of biological warfare agents as many instrumentation platforms and detection methodologies are developed and commissioned. Even then the threat of biological warfare agents and their use in bioterrorist attacks still remain a leading cause of global concern. Furthermore in the past decade there have been threats due to the emerging new diseases and also the re-emergence of old diseases and development of antimicrobial resistance and spread to new geographical regions. The preparedness against these agents need complete knowledge about the disease, better research and training facilities, diagnostic facilities and improved public health system. This review on the biological warfare agents will provide information on the biological warfare agents, their mode of transmission and spread and also the detection systems available to detect them. In addition the current information on the availability of commercially available and developing technologies against biological warfare agents has also been discussed. The risk that arise due to the use of these agents in warfare or bioterrorism related scenario can be mitigated with the availability of improved detection technologies.

  7. Biological warfare agents

    Science.gov (United States)

    Thavaselvam, Duraipandian; Vijayaraghavan, Rajagopalan

    2010-01-01

    The recent bioterrorist attacks using anthrax spores have emphasized the need to detect and decontaminate critical facilities in the shortest possible time. There has been a remarkable progress in the detection, protection and decontamination of biological warfare agents as many instrumentation platforms and detection methodologies are developed and commissioned. Even then the threat of biological warfare agents and their use in bioterrorist attacks still remain a leading cause of global concern. Furthermore in the past decade there have been threats due to the emerging new diseases and also the re-emergence of old diseases and development of antimicrobial resistance and spread to new geographical regions. The preparedness against these agents need complete knowledge about the disease, better research and training facilities, diagnostic facilities and improved public health system. This review on the biological warfare agents will provide information on the biological warfare agents, their mode of transmission and spread and also the detection systems available to detect them. In addition the current information on the availability of commercially available and developing technologies against biological warfare agents has also been discussed. The risk that arise due to the use of these agents in warfare or bioterrorism related scenario can be mitigated with the availability of improved detection technologies. PMID:21829313

  8. Green and social bonds - A promising tool

    International Nuclear Information System (INIS)

    Blanc, Dominique; Barochez, Aurelie de; Cozic, Aela

    2013-11-01

    Issues of green bonds, socially responsible bonds and climate bonds are on the rise. Novethic estimates that some Euro 5 billion in such bonds has been issued since the start of 2013 by development banks, the main issuers of this type of debt. The figure is equal to over half of their total issues since 2007. Including local authorities, corporations and banks, a total Euro 8 billion of these bonds has been issued thus far in 2013. Given the size of the bond market, which the OECD estimated at Euro 95,000 billion in 2011, green and social bonds are still something of a niche but have strong growth potential. A number of large issues, from Euro 500 million to Euro 1 billion, were announced at the end of the year. Unlike conventional bonds, green and social bonds are not intended to finance all the activities of the issuer or refinance its debt. They serve instead to finance specific projects, such as producing renewable energy or adapting to climate change, the risk of which is shouldered by the issuer. This makes them an innovative instrument, used to earmark investments in projects with a direct environmental or social benefit rather than simply on the basis of the issuer's sustainable development policy. With financing being sought for the ecological transition, green and social bonds are promising instruments, sketching out at global level the shape of tools adapted to the financing of a green economy. On the strength of these advantages, the interest of responsible investors - the main target of green and social bond issuers - is growing fast. Judging by issuer press releases and the most commonly used currencies, the main subscribers today are US investors, among them CalSTRS and fund managers like Calvert Investment Management and Trillium Asset Management. European asset owners are also starting to focus on green and social bonds. A Novethic survey shows that 13% of them have already subscribed to such an issue or plan to do so. The present study

  9. inventory management, VMI, software agents, MDV model

    Directory of Open Access Journals (Sweden)

    Waldemar Wieczerzycki

    2012-03-01

    Full Text Available Background: As it is well know, the implementation of instruments of logistics management is only possible with the use of the latest information technology. So-called agent technology is one of the most promising solutions in this area. Its essence consists in an entirely new way of software distribution on the computer network platform, in which computer exchange among themselves not only data, but also software modules, called just agents. The first aim is to propose the alternative method of the implementation of the concept of the inventory management by the supplier with the use of intelligent software agents, which are able not only to transfer the information but also to make the autonomous decisions based on the privileges given to them. The second aim of this research was to propose a new model of a software agent, which will be both of a high mobility and a high intelligence. Methods: After a brief discussion of the nature of agent technology, the most important benefits of using it to build platforms to support business are given. Then the original model of polymorphic software agent, called Multi-Dimensionally Versioned Software Agent (MDV is presented, which is oriented on the specificity of IT applications in business. MDV agent is polymorphic, which allows the transmission through the network only the most relevant parts of its code, and only when necessary. Consequently, the network nodes exchange small amounts of software code, which ensures high mobility of software agents, and thus highly efficient operation of IT platforms built on the proposed model. Next, the adaptation of MDV software agents to implementation of well-known logistics management instrument - VMI (Vendor Managed Inventory is illustrated. Results: The key benefits of this approach are identified, among which one can distinguish: reduced costs, higher flexibility and efficiency, new functionality - especially addressed to business negotiation, full automation

  10. Culturally Aware Agent Communication

    DEFF Research Database (Denmark)

    Rehm, Matthias; Nakano, Yukiko; Koda, Tomoko

    2012-01-01

    Agent based interaction in the form of Embodied Conversational Agents (ECAs) has matured over the last decade and agents have become more and more sophisticated in terms of their verbal and nonverbal behavior like facial expressions or gestures. Having such “natural” communication channels...... available for expressing not only task-relevant but also socially and psychologically relevant information makes it necessary to take influences into account that are not readily implemented like emotions or cultural heuristics. These influences have a huge impact on the success of an interaction...

  11. Systemic use of tumor necrosis factor alpha as an anticancer agent

    Science.gov (United States)

    Roberts, Nicholas J.; Zhou, Shibin; Diaz, Luis A.; Holdhoff, Matthias

    2011-01-01

    Tumor necrosis factor-α (TNF-α) has been discussed as a potential anticancer agent for many years, however initial enthusiasm about its clinical use as a systemic agent was curbed due to significant toxicities and lack of efficacy. Combination of TNF-α with chemotherapy in the setting of hyperthermic isolated limb perfusion (ILP), has provided new insights into a potential therapeutic role of this agent. The therapeutic benefit from TNF-α in ILP is thought to be not only due to its direct anti-proliferative effect, but also due to its ability to increase penetration of the chemotherapeutic agents into the tumor tissue. New concepts for the use of TNF-α as a facilitator rather than as a direct actor are currently being explored with the goal to exploit the ability of this agent to increase drug delivery and to simultaneously reduce systemic toxicity. This review article provides a comprehensive overview on the published previous experience with systemic TNF-α. Data from 18 phase I and 10 phase II single agent as well as 18 combination therapy studies illustrate previously used treatment and dose schedules, response data as well as the most prominently observed adverse effects. Also discussed, based on recent preclinical data, is a potential future role of systemic TNF-α in combination with liposomal chemotherapy to facilitate increased drug uptake into tumors. PMID:22036896

  12. Mobile Agent Data Integrity Using Multi-Agent Architecture

    National Research Council Canada - National Science Library

    McDonald, Jeffrey

    2004-01-01

    .... Security issues for mobile agents continue to produce research interest, particularly in developing mechanisms that guarantee protection of agent data and agent computations in the presence of malicious hosts...

  13. Perspectives in the development of hybrid bifunctional antitumour agents.

    Science.gov (United States)

    Musso, Loana; Dallavalle, Sabrina; Zunino, Franco

    2015-08-15

    In spite of the development of a large number of novel target-specific antitumour agents, the single-agent therapy is in general not able to provide an effective durable control of the malignant process. The limited efficacy of the available agents (both conventional cytotoxic and novel target-specific) reflects not only the expression of defence mechanisms, but also the complexity of tumour cell alterations and the redundancy of survival pathways, thus resulting in tumour cell ability to survive under stress conditions. A well-established strategy to improve the efficacy of antitumour therapy is the rational design of drug combinations aimed at achieving synergistic effects and overcoming drug resistance. An alternative strategy could be the use of agents designed to inhibit simultaneously multiple cellular targets relevant to tumour growth/survival. Among these novel agents are hybrid bifunctional drugs, i.e. compounds resulting by conjugation of different drugs or containing the pharmocophores of different drugs. This strategy has been pursued using various conventional or target-specific agents (with DNA damaging agents and histone deacetylase inhibitors as the most exploited compounds). A critical overview of the most representative compounds is provided with emphasis on the HDAC inhibitor-based hybrid agents. In spite of some promising results, the actual pharmacological advantages of the hybrid agents remain to be defined. This commentary summarizes the recent advances in this field and highlights the pharmacological basis for a rational design of hybrid bifunctional agents. Copyright © 2015. Published by Elsevier Inc.

  14. Delta agent (Hepatitis D)

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000216.htm Hepatitis D (Delta agent) To use the sharing features on this page, please enable JavaScript. Hepatitis D is a viral infection caused by the ...

  15. The NPT regime: Progress and promises

    International Nuclear Information System (INIS)

    Dhanapala, Jayantha

    2001-01-01

    Full text: Thesis. The 'NPT regime' has arrived at a fateful crossroads. Though extended indefinitely in 1995, its future is my no means secure. The future 'progress' of this treaty will depend upon whether the 'promises' of its States parties are fully implemented and, eventually, upon the treaty's success in achieving fully universal membership. Challenges The treaty faces many short-term and longer-term challenges: Short term - The first Preparatory Committee meeting for the 2005 Review Conference will meet next year. NNWS will want to see some evidence of progress on nuclear disarmament (Art. VI), along the lines prescribed in the 13 'practical steps' agreed at the last Review Conference. Yet progress has been set back by: uncertainties over the future of the ABM Treaty; the failure of START II and the CTBT to enter into force; the lack of a FISMAT treaty and a treaty establishing a NWFZ in Central Asia; continued qualitative improvements in nuclear weapons; hints that nuclear testing may one day resume; the persistence of doctrines of first-use, pre-emptive use, and use against states that use CBW. Other compliance-related questions will arise over safeguards (e.g. the inability of the IAEA to conduct inspections in the DPRK; signs of a breakdown of the norm of full-scope IAEA safeguards, e.g. in South Asia). There are also concerns over the implementation of non-proliferation commitments (e.g. persisting allegations about nuclear weapon programmes in existing NNWS). The terrorist attacks in New York and Washington, D.C. on 11 September should also serve as a reminder of the new terrorist dangers relating to the possible use of weapons of mass destruction and unorthodox delivery systems. Longer term - Selectivity in the enforcement of NPT norms; unilateralism; IAEA funding uncertainties and shortfalls; difficulties in reaching universal membership (India, Pakistan, and Israel); continuing compliance problems with respect to both non-proliferation and

  16. [Absorbable coronary stents. New promising technology].

    Science.gov (United States)

    Erbel, Raimund; Böse, Dirk; Haude, Michael; Kordish, Igor; Churzidze, Sofia; Malyar, Nasser; Konorza, Thomas; Sack, Stefan

    2007-06-01

    Coronary stent implantation started in Germany 20 years ago. In the beginning, the progress was very slow and accelerated 10 years later. Meanwhile, coronary stent implantation is a standard procedure in interventional cardiology. From the beginning of permanent stent implantation, research started to provide temporary stenting of coronary arteries, first with catheter-based systems, later with stent-alone technology. Stents were produced from polymers or metal. The first polymer stent implantation failed except the Igaki-Tamai stent in Japan. Newly developed absorbable polymer stents seem to be very promising, as intravascular ultrasound (IVUS) and optical coherence tomography have demonstrated. Temporary metal stents were developed based on iron and magnesium. Currently, the iron stent is tested in peripheral arteries. The absorbable magnesium stent (Biotronik, Berlin, Germany) was tested in peripheral arteries below the knee and meanwhile in the multicenter international PROGRESS-AMS (Clinical Performance and Angiographic Results of Coronary Stenting with Absorbable Metal Stents) study. The first magnesium stent implantation was performed on July 30, 2004 after extended experimental testing in Essen. The magnesium stent behaved like a bare-metal stent with low recoil of 5-7%. The stent struts were absorbed when tested with IVUS. Stent struts were not visible by fluoroscopy or computed tomography (CT) as well as magnetic resonance imaging (MRI). That means, that the magnesium stent is invisible and therefore CT and MRI can be used for imaging of interventions. Only using micro-CT the stent struts were visible. The absorption process could be demonstrated in a patient 18 days after implantation due to suspected acute coronary syndrome, which was excluded. IVUS showed a nice open lumen. Stent struts were no longer visible, but replaced by tissue indicating the previous stent location. Coronary angiography after 4 months showed an ischemia-driven target lesion

  17. Prosecuting the Leaders: Promises, Politics and Practicalities

    Directory of Open Access Journals (Sweden)

    Robert Cryer

    2009-02-01

    Full Text Available Given recent developments in relation to the prosecution of international crimes,  it might be thought that one of the last bastions of sovereignty has been breached, and international criminal law has not only entrenched itself in international law. Indeed further to this, it has assumed a supranational position that stands entirely above States, promising justice for all and as a trump card over depredations committed in the name of State sovereignty. After all, Charles Taylor from Liberia is standing trial before the Special Court for Sierra Leone, Slobodan Milošević only escaped judgment by the International Criminal Tribunal for the former

  18. Agents Within our Midst

    Science.gov (United States)

    2012-03-14

    agents; and the development of bio -monitoring protocols for civilian and service personnel during a chemical attack. These efforts have resulted in greater...produced by staphylococcal bacteria that is and is classified as a CDC select agent which has the potential to be used as a biological weapon .1...NMR chemical shift perturbation titrations with Fab (fragment, antigen binding regions) domains of 20B1, 14G8, and 6D3 using deuterated (2H) SEB

  19. Adrenal imaging agents

    International Nuclear Information System (INIS)

    Davis, M.A.; Hanson, R.N.; Holman, B.L.

    1980-01-01

    The goals of this proposal are the development of selenium-containing analogs of the aromatic amino acids as imaging agents for the pancreas and of the adrenal cortex enzyme inhibitors as imaging agents for adrenal pathology. The objects for this year include (a) the synthesis of methylseleno derivatives of phenylalanine and tryptophan, and (b) the preparation and evaluation of radiolabeled iodobenzoyl derivatives of the selenazole and thiazole analogs of metyrapone and SU-9055

  20. Antimicrobial Peptides: A Promising Therapeutic Strategy in Tackling Antimicrobial Resistance.

    Science.gov (United States)

    Nuti, Ramya; Goud, Nerella S; Saraswati, A Prasanth; Alvala, Ravi; Alvala, Mallika

    2017-01-01

    Antimicrobial resistance (AMR) has posed a serious threat to global public health and it requires immediate action, preferably long term. Current drug therapies have failed to curb this menace due to the ability of microbes to circumvent the mechanisms through which the drugs act. From the drug discovery point of view, the majority of drugs currently employed for antimicrobial therapy are small molecules. Recent trends reveal a surge in the use of peptides as drug candidates as they offer remarkable advantages over small molecules. Newer synthetic strategies like organometalic complexes, Peptide-polymer conjugates, solid phase, liquid phase and recombinant DNA technology encouraging the use of peptides as therapeutic agents with a host of chemical functions, and tailored for specific applications. In the last decade, many peptide based drugs have been successfully approved by the Food and Drug Administration (FDA). This success can be attributed to their high specificity, selectivity and efficacy, high penetrability into the tissues, less immunogenicity and less tissue accumulation. Considering the enormity of AMR, the use of Antimicrobial Peptides (AMPs) can be a viable alternative to current therapeutics strategies. AMPs are naturally abundant allowing synthetic chemists to develop semi-synthetics peptide molecules. AMPs have a broad spectrum of activity towards microbes and they possess the ability to bypass the resistance induction mechanisms of microbes. The present review focuses on the potential applications of AMPs against various microbial disorders and their future prospects. Several resistance mechanisms and their strategies have also been discussed to highlight the importance in the current scenario. Breakthroughs in AMP designing, peptide synthesis and biotechnology have shown promise in tackling this challenge and has revived the interest of using AMPs as an important weapon in fighting AMR. Copyright© Bentham Science Publishers; For any queries