1,716 research outputs found

    Apoptotic and chemotherapeutic properties of iron(III)-salophene in an ovarian cancer animal model

    Get PDF
    The cytotoxicity of organometallic compounds iron(III)-, cobalt(III)-, manganese(II)-, and copper(II)-salophene (-SP) on platinum-resistant ovarian cancer cell lines was compared. Fe-SP displayed selective cytotoxicity (IC 50 at ∼1 μM) against SKOV-3 and OVCAR-3 cell lines while Co-SP caused cytotoxic effects only at higher concentrations (IC50 at 60 ?M) and Cu-SP effects were negligible. High cytotoxicity of Mn-SP (30-60 μM) appeared to be nonspecific because the Mn-chloride salt reduced cell viability similarly. The effect of Fe-SP at 1 μM proved to be ovarian cancer cell selective when compared to a panel of cell lines derived from different tumors. The first irreversible step in the induction of cell death by Fe-SP occurred after 3 hrs as indicated by the mitochondrial transmembrane potential (ΔΨm) and was mainly linked to apoptotic, not necrotic events. To evaluate the toxicity of Fe-SP in vivo we conducted an acute toxicity study in rats. The LD 50 of Fe-SP is >2000 mg/kg orally and >5.5 mg/kg body weight by intraperitoneal injection. An ovarian cancer animal model showed that the chemotherapeutic relevant dose of Fe-SP in rats is 0.5-1 mg/kg body weight. The present report suggests that Fe-SP is a potential therapeutic drug to treat ovarian cancer. © 2009 Lange et al, publisher and licensee Dove Medical Press Ltd

    Sexual reprogramming and estrogenic sensitization in wild fish exposed to ethinylestradiol.

    Get PDF
    addresses: School of Biosciences, University of Exeter, Exeter EX4 4PS, United Kingdom. [email protected]: Journal Article; Research Support, Non-U.S. Gov'tCopyright © 2009 American Chemical Society. Post print version of article deposited. The final published version is available from: http://dx.doi.org/10.1021/es802661pGlobally, feminization responses in wild male freshwater fish are caused by exposure to estrogenic chemicals, including natural and synthetic estrogens, contained in effluentsfromwastewater treatment works. In U.K. rivers, feminization responses, including intersex, are widespread in wild roach (Rutilus rutilus) populations, and severely affected fish have a reduced reproductive success. We exposed roach to environmentally relevant concentrations of the contraceptive estrogen 17alpha-ethinylestradiol (EE2) for up to 2 years, including intermittent and repeated exposures,to determine effects on sexual development and subsequent responsiveness to estrogen. Exposure of roach to EE2 (at 4 ng/L) for 2 years resulted in sex reversal in males, leading to an all-female population with two cohorts in terms of their stages of ovarian development one paralleling the control females and one at a significantly less advanced stage, which we propose were sex-reversed males. Differing developmental and maturing rates of the putative sex-reversed males compared with control females would question their functional capability as females in the wild. Early-life exposure to environmentally relevant concentrations of EE2 sensitized females to estrogen, as determined by the measurement of the responses of estrogen-sensitive genes in a further EE2 challenge 398 days after the original exposure. In the wild, exposure to environmentally relevant concentrations of EE2 during early life has significantly wider implications for the sexual physiology in fish than has thus far been determined

    Low recurrence rate of a two-layered closure repair for primary and recurrent midline incisional hernia without mesh

    Get PDF
    Background: Incisional hernia is a serious complication after abdominal surgery and occurs in 11-23% of laparotomies. Repair can be done, for instance, with a direct suture technique, but recurrence rates are high. Recent literature advises the use of mesh repair. In contrast to this development, we studied the use of a direct suture repair in a separate layer technique. The objective of this retrospective observational study is to assess the outcomes (recurrences and complications) of a two-layered open closure repair for primary and recurrent midline incisional hernia without the use of mesh. Methods: In an observational retrospective cohort study, we analysed the hospital and outpatient records of 77 consecutive patients who underwent surgery for a primary or recurrent incisional hernia between 1st May 2002 and 8th November 2006. The repair consisted of separate continuous suturing of the anterior and posterior fascia, including the rectus muscle, after extensive intra-abdominal adhesiolysis. Results: Forty-one men (53.2%) and 36 women (46.8%) underwent surgery. Sixty-three operations (81.8%) were primary repairs and 14 (18.2%) were repairs for a recurrent incisional hernia. Of the 66 patients, on physical examination, three had a recurrence (4.5%) after an average follow-up of 2.6 years. The 30-day postoperative mortality was 1.1%. Wound infection was seen in five patients (6.5%). Conclusions: A two-layered suture repair for primary and recurrent incisional hernia repair without mesh with extensive adhesiolysis was associated with a recurrence rate comparable to mesh repair and had an acceptable complication rate

    Is telomere length socially patterned? Evidence from the West of Scotland Twenty-07 study

    Get PDF
    Lower socioeconomic status (SES) is strongly associated with an increased risk of morbidity and premature mortality, but it is not known if the same is true for telomere length, a marker often used to assess biological ageing. The West of Scotland Twenty-07 Study was used to investigate this and consists of three cohorts aged approximately 35 (N = 775), 55 (N = 866) and 75 years (N = 544) at the time of telomere length measurement. Four sets of measurements of SES were investigated: those collected contemporaneously with telomere length assessment, educational markers, SES in childhood and SES over the preceding twenty years. We found mixed evidence for an association between SES and telomere length. In 35-year-olds, many of the education and childhood SES measures were associated with telomere length, i.e. those in poorer circumstances had shorter telomeres, as was intergenerational social mobility, but not accumulated disadvantage. A crude estimate showed that, at the same chronological age, social renters, for example, were nine years (biologically) older than home owners. No consistent associations were apparent in those aged 55 or 75. There is evidence of an association between SES and telomere length, but only in younger adults and most strongly using education and childhood SES measures. These results may reflect that childhood is a sensitive period for telomere attrition. The cohort differences are possibly the result of survival bias suppressing the SES-telomere association; cohort effects with regard different experiences of SES; or telomere possibly being a less effective marker of biological ageing at older ages

    Lipophilic aroylhydrazone chelator HNTMB and its multiple effects on ovarian cancer cells

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Metal chelators have gained much attention as potential anti-cancer agents. However, the effects of chelators are often linked solely to their capacity to bind iron while the potential complexation of other trace metals has not been fully investigated. In present study, we evaluated the effects of various lipophilic aroylhydrazone chelators (AHC), including novel compound HNTMB, on various ovarian cancer cell lines (SKOV-3, OVCAR-3, NUTU-19).</p> <p>Methods</p> <p>Cell viability was analyzed via MTS cytotoxicity assays and NCI60 cancer cell growth screens. Apoptotic events were monitored via Western Blot analysis, fluorescence microscopy and TUNEL assay. FACS analysis was carried out to study Cell Cycle regulation and detection of intracellular Reactive Oxygen Species (ROS)</p> <p>Results</p> <p>HNTMB displayed high cytotoxicity (IC50 200-400 nM) compared to previously developed AHC (oVtBBH, HNtBBH, StBBH/206, HNTh2H/315, HNI/311; IC50 0.8-6 μM) or cancer drug Deferoxamine, a hexadentate iron-chelator (IC50 12-25 μM). In a NCI60 cancer cell line screen HNTMB exhibited growth inhibitory effects with remarkable differences in specificity depending on the cell line studied (GI50 10 nM-2.4 μM). In SKOV-3 ovarian cancer cells HNTMB treatment led to chromatin fragmentation and activation of the extrinsic and intrinsic pathways of apoptosis with specific down-regulation of Bcl-2. HNTMB caused delayed cell cycle progression of SKOV-3 through G2/M phase arrest. HNTMB can chelate iron and copper of different oxidation states. Complexation with copper lead to high cytotoxicity via generation of reactive oxygen species (ROS) while treatment with iron complexes of the drug caused neither cytotoxicity nor increased ROS levels.</p> <p>Conclusions</p> <p>The present report suggests that both, non-complexed HNTMB as a chelator of intracellular trace-metals as well as a cytotoxic HNTMB/copper complex may be developed as potential therapeutic drugs in the treatment of ovarian and other solid tumors.</p

    Isothiocyanate NB7M causes selective cytotoxicity, pro-apoptotic signalling and cell-cycle regression in ovarian cancer cells

    Get PDF
    The present report identifies indole-3-ethyl isothiocyanate NB7M as a potent cytotoxic agent with selective activity against cell lines derived from various tumour types. Ovarian cancer cell lines showed sensitivity to NB7M (60–70% cytotoxicity at 2.5 μM), in contrast to control cells (TCL-1 and HTR-8; IC50 ∼15 μM). In a screen performed by the National Cancer Institute (NCI) (NCI60 cancer cell-line assay) NB7M (NSC746077) reduced growth up to 100% with an IC50 between 0.1 and 10 μM depending on the cell line studied. Using SKOV-3 ovarian cancer cells as a model, mechanisms of cytotoxicity were analysed. NB7M caused hallmarks of apoptosis such as PARP-1 deactivation, chromatin condensation, DNA nicks, activation of caspases-9, -8, -3, loss of mitochondrial transmembrane depolarisation potential and upregulation of pro-apoptotic mitogen activated protein kinases (p38, SAP/JNK). NB7M downregulated phosphorylation of prosurvival kinases (PI-3K, AKT, IKKα), transcription factor NF-κB, and expression of DNA-Pk and AXL receptor tyrosine kinase. Subcytotoxic doses of NB7M inhibited DNA synthesis, caused G1-phase cell-cycle arrest and upregulated p27 expression. The present report suggests that NB7M is a selective cytotoxic agent in vitro for cell lines derived from ovarian and certain other tumours. In addition, NB7M acts as a growth/cell-cycle-suppressing agent and may be developed as a potential therapeutic drug to treat ovarian cancer

    Phenotypic Variation and Bistable Switching in Bacteria

    Get PDF
    Microbial research generally focuses on clonal populations. However, bacterial cells with identical genotypes frequently display different phenotypes under identical conditions. This microbial cell individuality is receiving increasing attention in the literature because of its impact on cellular differentiation, survival under selective conditions, and the interaction of pathogens with their hosts. It is becoming clear that stochasticity in gene expression in conjunction with the architecture of the gene network that underlies the cellular processes can generate phenotypic variation. An important regulatory mechanism is the so-called positive feedback, in which a system reinforces its own response, for instance by stimulating the production of an activator. Bistability is an interesting and relevant phenomenon, in which two distinct subpopulations of cells showing discrete levels of gene expression coexist in a single culture. In this chapter, we address techniques and approaches used to establish phenotypic variation, and relate three well-characterized examples of bistability to the molecular mechanisms that govern these processes, with a focus on positive feedback.
    corecore