HDAC inhibitor confers radiosensitivity to prostate stem-like cells

Background: Radiotherapy can be an effective treatment for prostate cancer, but radiorecurrent tumours do develop. Considering prostate cancer heterogeneity, we hypothesised that primitive stem-like cells may constitute the radiation-resistant fraction. Methods: Primary cultures were derived from patients undergoing resection for prostate cancer or benign prostatic hyperplasia. After short-term culture, three populations of cells were sorted, reflecting the prostate epithelial hierarchy, namely stem-like cells (SCs, α2β1integrinhi/CD133+), transit-amplifying (TA, α2β1integrinhi/CD133−) and committed basal (CB, α2β1integrinlo) cells. Radiosensitivity was measured by colony-forming efficiency (CFE) and DNA damage by comet assay and DNA damage foci quantification. Immunofluorescence and flow cytometry were used to measure heterochromatin. The HDAC (histone deacetylase) inhibitor Trichostatin A was used as a radiosensitiser. Results: Stem-like cells had increased CFE post irradiation compared with the more differentiated cells (TA and CB). The SC population sustained fewer lethal double-strand breaks than either TA or CB cells, which correlated with SCs being less proliferative and having increased levels of heterochromatin. Finally, treatment with an HDAC inhibitor sensitised the SCs to radiation. Interpretation: Prostate SCs are more radioresistant than more differentiated cell populations. We suggest that the primitive cells survive radiation therapy and that pre-treatment with HDAC inhibitors may sensitise this resistant fraction

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Termite soil as a potential low-cost adsorbent for the removal of methylene blue and malachite green dyes

The adsorption of methylene blue (MB) and malachite green (MG) from aqueous solution using a termite soil has been studied by batch adsorption technique. The adsorption experiments were carried out under different conditions of initial concentration (5–100 mg/L). The equilibrium data were fitted to Langmuir and Freundlich isotherms and the equilibrium adsorption was best described by the Langmuir isotherm model with maximum monolayer adsorption capacities found to be 338.98 and 327.21 mg/g at 305 K, respectively. Three kinetic models, pseudo-first-order, pseudo-second-order and intraparticle diffusion were employed to describe the adsorption mechanism. The experimental results showed that the pseudo-second-order equation is the best model that describes the adsorption behaviour with the coefficient of correlation R2 ≥0.99. Fourier transform infra red (FTIR) spectroscopy, X-ray diffraction (XRD), Scanning electron microscopy (SEM), Tunnelling electron microscopy (TEM) studies are evident that the termite soil has an effective adsorbent material.The results suggested that termite soil has high potential to be used as effective adsorbent for MB removal

KINETICS OF ADSORPTION OF VINYL SULPHONE RED DYE FROM AQUEOUS SOLUTION ONTO COMMERCIAL ACTIVATED CARBON

The adsorption of Vinyl Sulphone Red dye onto commercial activated carbon from aqueous solution was investigated. Batch mode adsorption experiment was carried out. The influence of various parameters such as agitation time, concentration of the dye solution, and adsorption dose were studied. Experimental data were fitted to the pseudo first order, pseudo second order and intra particle diffusion models. Kinetic parameters were calculated and discussed in detail