Assessment of aggregative growth of MnZn ferrite nanoparticles

MnZn ferrite (MnZnFe₂O₄, MZF) nanoparticles (NPs) represent an intriguing class of magnetic NPs in terms of composition-tunable magnetic properties, but the ability to control the size and morphology is essential to exploit such properties. This report describes the findings of an investigation of the size and morphology controllability in terms of growth kinetics of the NPs in a thermochemical synthesis process. MZF NPs of different sizes were synthesized at different temperatures. In addition to shape evolution, the overall size of the as-synthesized magnetic NPs is shown to increase with the reaction temperature and reaction time, revealing that the size growth process can be described by an aggregative growth mechanism. While the apparent rate constant decreases with the reaction temperature, the growth factor remains at 1-2, consistent with a low-dimensionality growth mode. Higher temperature and longer reaction time apparently favor the formation of cubic shapes. The dependence of the overall average particle size on the reaction temperature yields a diffusional activation energy in the order of 10-20 kJ mol^-1, a value slightly smaller than those reported for aggregative growth of other types of NPs in solutions. The unravelling of the kinetic parameters provides some new insights into the development of strategies for synthesizing MZF NPs with controllable sizes and shapes.

Breast conservation following neoadjuvant therapy for breast cancer in the modern era: Are we losing the opportunity?

The main rationale for neoadjuvant therapy for breast cancer is to provide effective systemic treatment while surgically down-staging the cancer. This down-staging was initially to convert inoperable patients to operable and later to increase rates of breast conservation in patients initially deemed mastectomy only candidates. Unexpectedly, in recent neoadjuvant trials lower rates of breast conservation have been observed than in past decades, despite remarkable advances in systemic therapies, which have increased pathologic complete response rates. These results point to factors aside from response and eligibility for breast conservation that may lead surgeons and/or patients to recommend and choose mastectomy. Here, we aim to examine the surgical benefits offered by the modern era neoadjuvant therapy and explore factors that have contributed to this decrease in breast conservation rates. If the main benefit of neoadjuvant therapy is to increase the opportunity for breast conservation, then our review suggests that to optimize less invasive surgical approaches, we will need to address both surgeon and patient-level variables and biases that may be limiting our ability to identify patients appropriate for less aggressive options. As an oncology community, we must be aware of the surgical overtreatment of breast cancer, especially in a time where systemic therapies have remarkably improved outcomes and responses.

Lab-on-a-Drone: Toward Pinpoint Deployment of Smartphone-Enabled Nucleic Acid-Based Diagnostics for Mobile Health Care

We introduce a portable biochemical analysis platform for rapid field deployment of nucleic acid-based diagnostics using consumer-class quadcopter drones. This approach exploits the ability to isothermally perform the polymerase chain reaction (PCR) with a single heater, enabling the system to be operated using standard 5 V USB sources that power mobile devices (via battery, solar, or hand crank action). Time-resolved fluorescence detection and quantification is achieved using a smartphone camera and integrated image analysis app. Standard sample preparation is enabled by leveraging the drone's motors as centrifuges via 3D printed snap-on attachments. These advancements make it possible to build a complete DNA/RNA analysis system at a cost of ∼$50 ($US). Our instrument is rugged and versatile, enabling pinpoint deployment of sophisticated diagnostics to distributed field sites. This capability is demonstrated by successful in-flight replication of Staphylococcus aureus and λ-phage DNA targets in under 20 min. The ability to perform rapid in-flight assays with smartphone connectivity eliminates delays between sample collection and analysis so that test results can be delivered in minutes, suggesting new possibilities for drone-based systems to function in broader and more sophisticated roles beyond cargo transport and imaging.

Development and evaluation of a secondary reference panel for BCR-ABL1 quantification on the International Scale

Molecular monitoring of chronic myeloid leukemia patients using robust BCR-ABL1 tests standardized to the International Scale (IS) is key to proper disease management, especially when treatment cessation is considered. Most laboratories currently use a time-consuming sample exchange process with reference laboratories for IS calibration. A World Health Organization (WHO) BCR-ABL1 reference panel was developed (MR¹–MR⁴), but access to the material is limited. In this study, we describe the development of the first cell-based secondary reference panel that is traceable to and faithfully replicates the WHO panel, with an additional MR^4.5 level. The secondary panel was calibrated to IS using digital PCR with ABL1, BCR and GUSB as reference genes and evaluated by 44 laboratories worldwide. Interestingly, we found that >40% of BCR-ABL1 assays showed signs of inadequate optimization such as poor linearity and suboptimal PCR efficiency. Nonetheless, when optimized sample inputs were used, >60% demonstrated satisfactory IS accuracy, precision and/or MR^4.5 sensitivity, and 58% obtained IS conversion factors from the secondary reference concordant with their current values. Correlation analysis indicated no significant alterations in %BCR-ABL1 results caused by different assay configurations. More assays achieved good precision and/or sensitivity than IS accuracy, indicating the need for better IS calibration mechanisms.

A cross-sectional analysis of the relationships of FAM components and their effects on quality of life in Chinese patients with chronic musculoskeletal pain

Introduction

A body of evidence has accrued supporting the Fear-Avoidance Model (FAM) of chronic pain which postulated the mediating role of pain-related fear in the relationships between pain catastrophizing and pain anxiety in affecting pain-related outcomes. Yet, relatively little data points to the extent to which the FAM be extended to understand chronic pain in Chinese population and its impact on quality of life (QoL).

Objective

This study explored the relationships between FAM components and their effects on QoL in a Chinese sample.

Methods

A total of 401 Chinese patients with chronic musculoskeletal pain completed measures of three core FAM components (pain catastrophizing, pain-related fear, and pain anxiety) and QoL. Cross-sectional structural equation modeling (SEM) assessed the goodness of fit of the FAM for two QoL outcomes, Physical (Model 1) and Mental (Model 2). In both models, pain catastrophizing was hypothesized to underpin pain-related fear, thereby influencing pain anxiety and subsequently QoL outcomes.

Results

Results of SEM evidenced adequate data-model fit (CFI30.90) for the two models tested (Model 1: CFI = 0.93; Model 2: CFI = 0.94). Specifically, pain catastrophizing significantly predicted pain-related fear (Model 1: stdb = 0.90; Model 2: stdb = 0.91), which in turn significantly predicted pain anxiety (Model 1: stdb = 0.92; Model 2: stdb = 0.929) and QoL outcomes in a negative direction (Model 1: stdb = −0.391; Model 2: stdb = −0.651) (all P < 0.001) (Table 1, Fig. 1).

Conclusion

Our data substantiated the existing FAM literature and offered evidence for the cross-cultural validity of the FAM in the Chinese population with chronic pain.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

The net suppression effect of pain catastrophic cognition on anxiety sensitivity

Introduction

The existing literature on chronic pain points to the effects anxiety sensitivity, pain hypervigilance, and pain catastrophizing on pain-related fear; however, the nature of the relationships remains unclear. The three dispositional factors may affect one another in the prediction of pain adjustment outcomes. The addition of one disposition may increase the association between another disposition and outcomes, a consequence known as suppressor effects in statistical terms.

Objective

This study examined the possible statistical suppressor effects of anxiety sensitivity, pain hypervigilance and pain catastrophizing in predicting pain-related fear and adjustment outcomes (disability and depression).

Methods

Chinese patients with chronic musculoskeletal pain (n = 401) completed a battery of assessments on pain intensity, depression, anxiety sensitivity, pain vigilance, pain catastrophizing, and pain-related fear. Multiple regression analyses assessed the mediating/moderating role of pain hypervigilance. Structural equation modeling (SEM) was used to evaluate suppression effects.

Results

Our results evidenced pain hypervigilance mediated the effects of anxiety sensitivity (Model 1: Sobel z = 4.86) and pain catastrophizing (Model 3: Sobel z = 5.08) on pain-related fear. Net suppression effect of pain catastrophizing on anxiety sensitivity was found in SEM where both anxiety sensitivity and pain catastrophizing were included in the same full model to predict disability (Model 9: CFI = 0.95) and depression (Model 10: CFI = 0.93) (all P < 0.001) (see Figs. 3 and 4, Figs. 1 and 2).

Conclusions

Our findings evidenced that pain hypervigilance mediated the relationship of two dispositional factors, pain catastrophic cognition and anxiety sensitivity, with pain-related fear. The net suppression effects of pain catastrophizing suggest that anxiety sensitivity enhanced the effect of pain catastrophic cognition on pain hypervigilance.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Abstract P2-05-21: The AKT-mTOR pathway as a potential organ-specific drug target signature of hepatic metastases from breast cancer

Background: The identification of organ-specific targetable signatures may help design more effective treatment for patients with metastatic breast cancer (MBC). We took a multi-OMIC approach to assess whether the AKT-mTOR pathway is globally activated during metastatic progression or whether it represents an organ-specific target.

Methods: Snap frozen biopsies from 25 MBC patients enrolled in a prospective phase II trial were used. Sites of metastasis were classified as liver (n=8) and others (n=17), the latter including cutaneous, lung, lymph nodes, and intra-abdominal lesions. Signaling analysis of the 25 cases was performed using Reverse Phase Protein Microarray (RPPA) coupled with Laser Capture Microdissection. Activation of the AKT-mTOR pathway was quantified as phosphorylation of AKT (S473) and the mTOR target p70S6 (T389). Matched exome (WES) and RNASeq data were available for 17 of 25 patients, five with liver metastases. Sequencing data was processed using an in-house developed pipeline to identify somatic events including coding mutations, copy number alterations, gene fusions, and differential expression. Activation of the AKT-mTOR pathway and sequencing data were compared between hepatic and non-hepatic lesions using an integrated RPPA and genomic approach.

Results: Among liver metastases, AKT was activated in 4 of the 8 (50.0%) patients, while 6 of the 8 cases (75.0%) showed activation of p70S6. Sequencing data revealed mutation of PIK3CA in 4 of the 5 liver metastases (80.0%). Three of the PIK3CA mutated specimens with catalytic domain mutations (codons 1023 and 147) demonstrated co-activation of AKT and p70S6, while the fourth case, containing a helical domain mutation (E542K), had activation of p70S6 only. The PIK3CA wild-type liver metastasis demonstrated low activation of AKT and p70S6. For non-hepatic metastases AKT was activated in 2 of the 17 cases (11.8%) and p70S6 in 5 of the 17 patients (29.4%).

Discussion: Although these results need further validation, activation of the AKT-mTOR pathway appears to be a hepatic specific signature in MBC and could be used for the selection of targeted agents for hepatic lesions.

Citation Format: Pierobon M, Wong S, Reeder A, Anthony SP, Robert NJ, Northfelt DW, Jahanzeb M, Vocila L, Wulfkuhle J, Dunetz B, Aldrich J, Byron S, Craig D, Liotta L, Petricoin EF, Carpten J. The AKT-mTOR pathway as a potential organ-specific drug target signature of hepatic metastases from breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-05-21.

Abstract P3-12-02: Patient prognostic score and survival benefit offered by radiotherapy for ductal carcinoma in situ

Background: In general, radiotherapy (RT) follows breast-conserving surgery (BCS) and remains the standard of care for the surgical management of both invasive carcinoma and ductal carcinoma in situ (DCIS). Although it is associated with better local control, the magnitude of survival benefit conferred by RT for DCIS has not yet been established. We sought to evaluate whether a survival benefit exists with the addition of RT for patients with DCIS and to validate a patient prognostic score to predict survival benefit.

Methods: We performed a retrospective longitudinal cohort study by using the Surveillance Epidemiology and End Results database (SEER 17). Between 1988-2007, we identified 32,144 eligible patients who underwent BCS for DCIS. Using age, year of diagnosis, race, tumor size, hormone receptor status, tumor grade, marital status and SEER region, we calculated propensity score weights to balance clinicopathologic factors between patients receiving only surgery and those receiving surgery and RT. This cohort was divided into seven groups according to the previously validated patient prognostic score proposed by Smith et al. Breast cancer mortality (BCM) was assessed using a log-rank test and a multivariable Cox proportional hazards model.

Results: Of 32,144 cases of DCIS, 20,329 cases (63%) were treated with RT (+RT group) and 11,815 cases (37%) were treated with surgery alone (-RT group). There were 304 breast cancer-specific deaths observed over the follow-up period (median 96 months). The weighted cumulative incidence of BCM at ten-years was 1.8% for the +RT group compared to 2.1% for the -RT group (p= 0.003). The effect of RT on survival differed by nuclear grade (p= 0.007), age (p= 0.004), and tumor size (p=0.02). We found that the survival benefit for the +RT group was significantly greater than for the –RT group in subgroups of patients with higher nuclear grade, younger age, and larger tumor size, whereas a statistical reduction of BCM with RT was not observed among patients without these prognostic factors. Moreover, the magnitude of survival benefit was significantly correlated with the patient prognostic score [p&lt;0.0001, Table].

Conclusion: In this population-based cohort study, the patient prognostic score for DCIS accurately estimated the magnitude of survival benefit offered by radiotherapy after BCS, suggesting that decisions for RT could be tailored based on prognostic score and patient preference. Limitations of this study include unmeasured confounders such as a lack of information about patients' comorbidities, margin status and endocrine therapy, and further external validation is needed to confirm our results.

Patient Prognostic Score and Hazard Ratio (HR) Comparing Mortality between Radiotherapy Group and non-Radiotherapy GroupPatient Prognostic ScoreNumber of patients in -RT groupNumber of patients in +RT groupWeighted HR of BCM95% CIWeighted HR of OM95% CI078213881.20.67 - 2.10.910.76 - 1.11267744801.00.70 - 1.50.880.78 - 0.992410570800.690.51 - 0.940.710.63 - 0.793304854170.730.48 - 1.10.680.58 - 0.81496517010.310.16 - 0.580.420.30 - 0.5852232480.290.09 - 0.910.430.21 - 0.9161515N.A. N.A. Abbreviation: RT, Radiotherapy; BCM, Breast Cancer Mortality; OM, Overall Mortality: N.A., not available

Citation Format: Sagara Y, Freedman RA, Vaz-Luis I, Mallory MA, Wong S, Aydogan F, DeSantis S, Barry WT, Golshan M. Patient prognostic score and survival benefit offered by radiotherapy for ductal carcinoma in situ. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-12-02.

A Study of the Reliability and Concurrent Validity of the Chinese Version of the Pain Medication Attitude Questionnaire (ChPMAQ) in a Sample of Chinese Patients with Chronic Pain

OBJECTIVES

The Pain Medication Attitude Questionnaire (PMAQ) was designed to assess concerns about pain medication among patients with chronic nonmalignant pain. The instrument has been demonstrated to be a reliable measure with good psychometric properties, yet its validity among Chinese has not been evaluated. This study aimed to translate the English-language version of the PMAQ into Chinese (ChPMAQ) and to evaluate its reliability and concurrent validity.

METHODS

A total of 201 Chinese patients with chronic pain attending two multidisciplinary pain clinics in Hong Kong completed the ChPMAQ, the Chronic Pain Grade (CPG) questionnaire, the mental health subscale of the SF-12 (QoL-Mental), and questions assessing sociodemographic and pain characteristics.

RESULTS

Our results showed that the seven ChPMAQ scales possessed good internal consistency. Except for the correlation between Withdrawal and Mistrust (r = 0.13), all ChPMAQ scales were significantly correlated with each other (all p < 0.01). The scales also correlated with two concurrent criterion measures, QoL-Mental and Pain Disability, in a predictable direction. Results of hierarchical multiple regression analyses showed that the ChPMAQ scales predicted concurrent QoL-Mental (F(7,190) = 2.75, p < 0.05) and pain disability (F(7,188) = 3.00, p < 0.01). Need (std β = -0.23, p<0.05) and Side effects (std β = 0.27, p < 0.01) emerged as independent predictors of concurrent QoL-Mental and pain disability, respectively.

CONCLUSION

Despite the current preliminary findings for the reliability and concurrent validity of the ChPMAQ, more research is needed to substantiate the reliability, validity and other psychometric properties of the instrument.