nanoparticle-tracking-analysis-gold-nanoparticles-aqueous-media

Nanoparticle Tracking Analysis of Gold Nanoparticles in Aqueous Media through an Inter-Laboratory Comparison

In the field of nanotechnology, analytical characterization plays a vital role in understanding the behavior and toxicity of nanomaterials (NMs). ...

uv-vis-spectroscopic-characterization-nanomaterials-aqueous

UV-Vis Spectroscopic Characterization of Nanomaterials in Aqueous Media

The physicochemical characterization of nanomaterials (NMs) is often an analytical challenge, due to their small size (at least one dimension in the ...

University of Oxford

Radical radiotherapy and surgery achieve similar cure rates in muscle-invasive bladder cancer, but the choice of which treatment would be most beneficial cannot currently be predicted for individual patients. The primary aim of this study was to assess whether expression of any of a panel of DNA damage signaling proteins in tumor samples taken before irradiation could be used as a predictive marker of radiotherapy response, or rather was prognostic. Protein expression of MRE11, RAD50, NBS1, ATM, and H2AX was studied by immunohistochemistry in pretreatment tumor specimens from two cohorts of bladder cancer patients (validation cohort prospectively acquired) treated with radical radiotherapy and one cohort of cystectomy patients. In the radiotherapy test cohort (n = 86), low tumor MRE11 expression was associated with worse cancer-specific survival compared with high expression [43.1% versus 68.7% 3-year cause-specific survival (CSS), P = 0.012] by Kaplan-Meier analysis. This was confirmed in the radiotherapy validation cohort (n = 93; 43.0% versus 71.2%, P = 0.020). However, in the cystectomy cohort (n = 88), MRE11 expression was not associated with cancer-specific survival, commensurate with MRE11 being a predictive marker. High MRE11 expression in the combined radiotherapy cohort had a significantly better cancer-specific survival compared with the high-expression cystectomy cohort (69.9% versus 53.8% 3-year CSS, P = 0.021). In this validated immunohistochemistry study, MRE11 protein expression was shown and confirmed as a predictive factor associated with survival following bladder cancer radiotherapy, justifying its inclusion in subsequent trial designs. MRE11 expression may ultimately allow patient selection for radiotherapy or cystectomy, thus improving overall cure rates.

MRE11 expression is predictive of cause-specific survival following radical radiotherapy for muscle-invasive bladder cancer.

We report the selective electrochemical detection of cysteine in the presence of homocysteine and glutathione with the use of an electrode modified with cyclotricatechylene (CTC). A carbon electrode was first modified with cyclotriveratrylene (CTV) and then electrochemically converted into CTC. Using cyclic voltammetry, the redox activity of CTC was investigated along with its electrochemical response to cysteine and the closely related compounds, glutathione and homocysteine which are commonly found in biological media alongside cysteine. The selective detection of cysteine was achieved with the use of the electrocatalytic oxidation reaction and exploiting the different rates of reaction of each thiol with the oxidized CTC via variable scan rate studies. The analytical parameters consisting of sensitivity, range of linear detection, and limit of detection were determined for selective cysteine detection in phosphate buffer solution and tissue culture media where the sensitivity of the system is ca. 0.023 μA μM(-1) and ca. 0.031 μA μM(-1) with a limit of detection of ca. 0.6 μM and ca. 0.9 μM for buffer solution and tissue culture media respectively. Practical assessment of this analytical method was carried out in mixed solutions containing a combination of cysteine, homocysteine and glutathione in both media. The determined results agree well with the added cysteine content. This work presents a novel way of utilizing CTC into detecting cysteine, and is well-suited for bio-marker sensing. 

Selective electrochemical determination of cysteine with a cyclotricatechylene modified carbon electrode.

Through-electrode thickness honeycomb architectures were layer-by-layer self-assembled directly through a scalable printing process for ultrapower hybrid lithium-ion capacitor applications. Initially, the electrochemical performance of the pore-array electrodes was investigated as a function of the active material type (graphene plates, carbon nanofibers, and activated carbon). Inactive components (conductive carbon and polymer binder) were then minimized to 5 wt %. Finally, an optimized activated carbon-based cathode was paired with a spray-printed LiTiO-based anode and a range of anode-to-cathode mass ratios in a lithium-ion capacitor arrangement were investigated. A 1:5 anode/cathode mass ratio provided an attractive energy density comparable with a LiTiO/LiFePO lithium-ion battery but with outstanding power capability that was an order of magnitude greater than typical for lithium-ion batteries. The pore-array electrode was reproduced over areas of 20 cm × 15 cm in a double-sided coated configuration, and the option for selectively patterning electrodes was also demonstrated.

Scalable, Large-Area Printing of Pore-Array Electrodes for Ultrahigh Power Electrochemical Energy Storage.

To determine trends in clinical practice for individuals with DSD requiring gonadectomy.

ArticleTotal : 2	Year
Publication title Cited by 11	2020
Publication title Cited by 25	2021

Article	Year
MRE11 expression is predictive of cause-specific survival following radical radiotherapy for muscle-invasive bladder cancer. Cancer research\| PubMed ID: 20843819	2010
Selective electrochemical determination of cysteine with a cyclotricatechylene modified carbon electrode. The Analyst\| PubMed ID: 25407642	2015
Scalable, Large-Area Printing of Pore-Array Electrodes for Ultrahigh Power Electrochemical Energy Storage. ACS applied materials & interfaces\| PubMed ID: 31553158	2019
Gonadectomy in conditions affecting sex development: a registry-based cohort study. European journal of endocrinology\| PubMed ID: 33780351	2021

Colin Johnston

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