Roadmap to clinical use of gold nanoparticles for radiation sensitization

The past decade has seen a dramatic increase in interest in the use of gold nanoparticles (GNPs) as radiation sensitizers for radiation therapy. This interest was initially driven by their strong absorption of ionizing radiation and the resulting ability to increase dose deposited within target volumes even at relatively low concentrations. These early observations are supported by extensive experimental validation, showing GNPs' efficacy at sensitizing tumors in both in vitro and in vivo systems to a range of types of ionizing radiation, including kilovoltage and megavoltage X rays as well as charged particles. Despite this experimental validation, there has been limited translation of GNP-mediated radiation sensitization to a clinical setting. One of the key challenges in this area is the wide range of experimental systems that have been investigated, spanning a range of particle sizes, shapes, and preparations. As a result, mechanisms of uptake and radiation sensitization have remained difficult to clearly identify. This has proven a significant impediment to the identification of optimal GNP formulations which strike a balance among their radiation sensitizing properties, their specificity to the tumors, their biocompatibility, and their imageability in vivo. This white paper reviews the current state of knowledge in each of the areas concerning the use of GNPs as radiosensitizers, and outlines the steps which will be required to advance GNP-enhanced radiation therapy from their current pre-clinical setting to clinical trials and eventual routine usage.

Intraclonal heterogeneity is a critical early event in the development of myeloma and precedes the development of clinical symptoms.

The mechanisms involved in the progression from monoclonal gammopathy of undetermined significance (MGUS) and smoldering myeloma (SMM) to malignant multiple myeloma (MM) and plasma cell leukemia (PCL) are poorly understood but believed to involve the sequential acquisition of genetic hits. We performed exome and whole-genome sequencing on a series of MGUS (n=4), high-risk (HR)SMM (n=4), MM (n=26) and PCL (n=2) samples, including four cases who transformed from HR-SMM to MM, to determine the genetic factors that drive progression of disease. The pattern and number of non-synonymous mutations show that the MGUS disease stage is less genetically complex than MM, and HR-SMM is similar to presenting MM. Intraclonal heterogeneity is present at all stages and using cases of HR-SMM, which transformed to MM, we show that intraclonal heterogeneity is a typical feature of the disease. At the HR-SMM stage of disease, the majority of the genetic changes necessary to give rise to MM are already present. These data suggest that clonal progression is the key feature of transformation of HR-SMM to MM and as such the invasive clinically predominant clone typical of MM is already present at the SMM stage and would be amenable to therapeutic intervention at that stage.

The Use of a Pressure-Indicating Sensor Film to Provide Feedback upon Hydrogel-Forming Microneedle Array Self-Application In Vivo

PURPOSE:
To evaluate the combination of a pressure-indicating sensor film with hydrogel-forming microneedle arrays, as a method of feedback to confirm MN insertion in vivo.
METHODS:
Pilot in vitro insertion studies were conducted using a Texture Analyser to insert MN arrays, coupled with a pressure-indicating sensor film, at varying forces into excised neonatal porcine skin. In vivo studies involved twenty human volunteers, who self-applied two hydrogel-forming MN arrays, one with a pressure-indicating sensor film incorporated and one without. Optical coherence tomography was employed to measure the resulting penetration depth and colorimetric analysis to investigate the associated colour change of the pressure-indicating sensor film.
RESULTS:
Microneedle insertion was achieved in vitro at three different forces, demonstrating the colour change of the pressure-indicating sensor film upon application of increasing pressure. When self-applied in vivo, there was no significant difference in the microneedle penetration depth resulting from each type of array, with a mean depth of 237 μm recorded. When the pressure-indicating sensor film was present, a colour change occurred upon each application, providing evidence of insertion.
CONCLUSIONS:
For the first time, this study shows how the incorporation of a simple, low-cost pressure-indicating sensor film can indicate microneedle insertion in vitro and in vivo, providing visual feedback to assure the user of correct application. Such a strategy may enhance usability of a microneedle device and, hence, assist in the future translation of the technology to widespread clinical use.

A 'before and after' study of nursing students' self-assessed competence in identifying the needs of older patients in hospital using an educational workbook.

Background: A core component of nurse education is clinical practice in order to support the development of clinical skills and competence. Assessment and measurement of the clinical competence of nursing students is important to gauge their professional development and educational needs.

Aim: To evaluate the impact of an Older Persons’ Assessment Educational Workbook (OPAEW) and explore second year nursing students’ competence and their opinions and use of the workbook.

Methods: A ‘before and after’ pre-experimental design was undertaken with n=6 second year nursing students. Outcome measures were the Nursing Competencies Questionnaire and the Self-efficacy in Clinical Performance Scale. Content analysis of workbooks and a survey (n=5) of opinions regarding the workbook was undertaken.

Findings: Pre and post test results for the study (n=5) were tested to determine if there was a relationship between changes in the NCQ and SECP repeated measures and use of an OPAEW. Testing identified evidence of a statistically significant difference for both SECP measures (SECP28 p=0.043; SECP7 p=0.042), with no clear statistical evidence of a difference for the NCQ (p=0.08). A weak negative association (NCQ ρ=-0.600 p=0.285; SECP28 ρ=-0.300 p=0.624; SECP7 ρ=-0.205 p=0.741), was found indicating that those participants who scored the lowest scores at the start of the study, benefited most from the workbook.

Content analysis of the OPAEW (n=5) found that 3 of the 5 participants completed all components of the workbook, with a mean of 1051 words used (SD 281.8). Through the survey (n=5) students reported the workbook as a useful guide when undertaking a patient assessment.

Conclusions: The OPAEW showed potential as an intervention to support the development of nursing students’ competence in older person assessment skills.

A 'before and after' study of nursing students' self-assessed competence in identifying the needs of older patients in hospital using an educational workbook.

Background: A core component of nurse education is clinical practice in order to support the development of clinical skills and competence. Assessment and measurement of the clinical competence of nursing students is important to gauge their professional development and educational needs.

Aim: To evaluate the impact of an Older Persons’ Assessment Educational Workbook (OPAEW) and explore second year nursing students’ competence and their opinions and use of the workbook.

Methods: A ‘before and after’ pre-experimental design was undertaken with n=6 second year nursing students. Outcome measures were the Nursing Competencies Questionnaire and the Self-efficacy in Clinical Performance Scale. Content analysis of workbooks and a survey (n=5) of opinions regarding the workbook was undertaken.

Findings: Pre and post test results for the study (n=5) were tested to determine if there was a relationship between changes in the NCQ and SECP repeated measures and use of an OPAEW. Testing identified evidence of a statistically significant difference for both SECP measures (SECP28 p=0.043; SECP7 p=0.042), with no clear statistical evidence of a difference for the NCQ (p=0.08). A weak negative association (NCQ ρ=-0.600 p=0.285; SECP28 ρ=-0.300 p=0.624; SECP7 ρ=-0.205 p=0.741), was found indicating that those participants who scored the lowest scores at the start of the study, benefited most from the workbook.

Content analysis of the OPAEW (n=5) found that 3 of the 5 participants completed all components of the workbook, with a mean of 1051 words used (SD 281.8). Through the survey (n=5) students reported the workbook as a useful guide when undertaking a patient assessment.

Conclusions: The OPAEW showed potential as an intervention to support the development of nursing students’ competence in older person assessment skills.

Testing the psychometric properties of two self-report clinical competence scales for nursing students.

Background: It is important to assess the clinical competence of nursing students to gauge their educational needs. Competence can be measured by self-assessment tools; however, Anema and McCoy (2010) contend that currently available measures should be further psychometrically tested.
Aim: To test the psychometric properties of Nursing Competencies Questionnaire (NCQ) and Self-Efficacy in Clinical Performance (SECP) clinical competence scales.
Method: A non-randomly selected sample of n=248 2nd year nursing students completed NCQ, SECP and demographic questionnaires (June and September 2013). Mokken Scaling Analysis (MSA) was used to investigate structural validity and scale properties; convergent and discriminant validity and reliability were also tested for each scale.
Results: MSA analysis identified that the NCQ is a unidimensional scale with strong scale scalability coefficients Hs =0.581; but limited item rankability HT =0.367. The SECP scale MSA suggested that the scale could be potentially split into two unidimensional scales (SECP28 and SECP7), each with good/reasonable scalablity psychometric properties as summed scales but negligible/very limited scale rankability (SECP28: Hs = 0.55, HT=0.211; SECP7: Hs = 0.61, HT=0.049). Analysis of between cohort differences and NCQ/SECP scores produced evidence of discriminant and convergent validity; good internal reliability was also found: NCQ α = 0.93, SECP28 α = 0.96 and SECP7 α=0.89.

Discussion: In line with previous research further evidence of the NCQ’s reliability and validity was demonstrated. However, as the SECP findings are new and the sample small with reference to Straat and colleagues (2014), the SECP results should be interpreted with caution and verified on a second sample.
Conclusions: Measurement of perceived self-competence could start early in a nursing programme to support students’ development of clinical competence. Further testing of the SECP scale with larger nursing student samples from different programme years is indicated.

References:
Anema, M., G and McCoy, JK. (2010) Competency-Based Nursing Education: Guide to Achieving Outstanding Learner Outcomes. New York: Springer.
Straat, JH., van der Ark, LA and Sijtsma, K. (2014) Minimum Sample Size Requirements for Mokken Scale Analysis Educational and Psychological Measurement 74 (5), 809-822.

A new generation of companion diagnostics: cobas BRAF, KRAS and EGFR mutation detection tests

The cobas® (Roche) portfolio of companion diagnostics in oncology currently has three assays CE-marked for in vitro diagnostics. Two of these (EGFR and BRAF) are also US FDA-approved. These assays detect clinically relevant mutations that are correlated with response (BRAF, EGFR) or lack of response (KRAS) to targeted therapies such as selective mutant BRAF inhibitors in malignant melanoma, tyrosine kinases inhibitor in non-small cell lung cancer and anti-EGFR monoclonal antibodies in colorectal cancer, respectively. All these assays are run on a single platform using DNA extracted from a single 5 µm section of a formalin-fixed paraffin-embedded tissue block. The assays provide an ‘end-to-end’ solution from extraction of DNA to automated analysis and report on the cobas z 480. The cobas tests have shown robust and reproducible performance, with high sensitivity and specificity and low limit of detection, making them suitable as companion diagnostics for clinical use.