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This article discusses the importance of understanding research paradigms in medical education and provides a method for novice researchers to deconstruct their own paradigms. The authors use gamification techniques and Socratic questioning to guide researchers in thinking openly about their assumptions and improving the conduct of research. The article emphasizes the need for healthcare professionals to be aware of different paradigms, such as positivism, interpretivism, and critical theory, and how these paradigms can influence research methodology. The authors believe that their approach can be applied to researchers in other disciplines and can help educators teach the philosophy of research practice. [Extracted from the article]

Introduction: Persistent pain following breast surgery is common and may be challenging to treat. In patients refractory to conservative treatments, ultrasound‐guided fascial plane blocks of thoracic nerves can be a useful option. Results: This type of neuro blockade technique provides advantages in terms of safety and efficacy that are convenient for physicians managing refractory and complex cases of post‐breast surgery syndrome. Conclusion: This technical review aims to present an up‐to‐date summary of the most common ultrasound‐guided fascial plane blocks for chronic pain in post‐breast surgery patients, provide a detailed technical description of each intervention, and propose preferred injections based on the anatomical location of the pain. [ABSTRACT FROM AUTHOR]

The article provides information on a learning activity for medical students that uses Play-Doh as a tool to teach creative data collection. Topics discussed include steps involved in the learning activity, reason for including a variety of colours when purchasing more Play-Doh for the next cohort, and lessons learned from the activity.

Background: To evaluate risk factors (treatment-related, comorbidities, and lifestyle) for breast cancer-related lymphedema (BCRL) within the context of a Prospective Surveillance and Early Intervention (PSEI) model of care for subclinical BCRL.Methods: The parent randomized clinical trial assigned patients newly diagnosed with breast cancer to PSEI with either bioimpedance spectroscopy (BIS) or tape measurement (TM). Surgical, systemic and radiation treatments, comorbidities, and lifestyle factors were recorded. Detection of subclinical BCRL (change from baseline of either BIS L-Dex ≥6.5 or tape volume ≥ 5% and < 10%) triggered an intervention with compression therapy. Volume change from baseline ≥10% indicated progression to chronic lymphedema and need for complex decongestive physiotherapy. In this secondary analysis, multinomial logistic regressions including main and interaction effects of the study group and risk factors were used to test for factor associations with outcomes (no lymphedema, subclinical lymphedema, progression to chronic lymphedema after intervention, progression to chronic lymphedema without intervention). Post hoc tests of significant interaction effects were conducted using Bonferroni-corrected alphas of .008; otherwise, an alpha of .05 was used for statistical significance.Results: The sample (n = 918; TM = 457; BIS = 461) was female with a median age of 58.4 years. Factors associated with BCRL risk included axillary lymph node dissection (ALND) (p < .001), taxane-based chemotherapy (p < .001), regional nodal irradiation (RNI) (p ≤ .001), body mass index >30 (p = .002), and rurality (p = .037). Mastectomy, age, hypertension, diabetes, seroma, smoking, and air travel were not associated with BCRL risk.Conclusions: Within the context of 3 years of PSEI for subclinical lymphedema, variables of ALND, taxane-based chemotherapy, RNI, body mass index >30, and rurality increased risk. [ABSTRACT FROM AUTHOR]

Methylglyoxal (MG) production after myocardial infarction (MI) leads to advanced glycation end‐product formation, adverse remodeling, and loss of cardiac function. The extracellular matrix (ECM) is a main target for MG glycation. This suggests that ECM‐mimicking biomaterial therapies may protect the post‐MI environment by removing MG. In this study, mechanisms by which a recombinant human collagen type I hydrogel therapy confers cardioprotection are investigated. One‐week post‐MI, mice receive intramyocardial injection of hydrogel or PBS. The hydrogel improves border zone contractility after 2 days, which is maintained for 28 days. RNA sequencing shows that hydrogel treatment decreases the expression of erythroid differentiation regulator 1, a factor associated with apoptosis. Hydrogel treatment reduces cardiomyocyte apoptosis and oxidative stress at 2 days with greater myocardial salvage seen at 28 days. The hydrogel located at the epicardial surface is modified by MG, and less MG‐modified proteins are observed in the underlying myocardium of hydrogel‐treated mice. Biomaterials that can be a target for MG glycation may act as a sponge to remove MG from the myocardium post‐MI. This leads to less oxidative stress, greater survival and contractility of cardiomyocytes, which altogether suggests a novel mechanism by which biomaterials improve function of the infarcted heart. [ABSTRACT FROM AUTHOR]

Cell Communication Network factor 4 (CCN4/WISP1) is a matricellular protein secreted by cancer cells that promotes metastasis by inducing the epithelial–mesenchymal transition. While metastasis limits survival, limited anti‐tumor immunity also associates with poor patient outcomes with recent work linking these two clinical correlates. Motivated by increased CCN4 correlating with dampened anti‐tumor immunity in primary melanoma, we test for a direct causal link by knocking out CCN4 (CCN4 KO) in the B16F0 and YUMM1.7 mouse melanoma models. Tumor growth is reduced when CCN4 KO melanoma cells are implanted in immunocompetent but not in immunodeficient mice. Correspondingly, CD45+ tumor‐infiltrating leukocytes are significantly increased in CCN4 KO tumors, with increased natural killer and CD8+ T cells and reduced myeloid‐derived suppressor cells (MDSC). Among mechanisms linked to local immunosuppression, CCN4 suppresses IFN‐gamma release by CD8+ T cells and enhances tumor secretion of MDSC‐attracting chemokines like CCL2 and CXCL1. Finally, CCN4 KO potentiates the anti‐tumor effect of immune checkpoint blockade (ICB) therapy. Overall, our results suggest that CCN4 promotes tumor‐induced immunosuppression and is a potential target for therapeutic combinations with ICB. Synopsis: Cell Communication Network factor 4, a secreted matricellular protein that promotes metastasis in melanoma, also suppresses anti‐tumor immunity via autocrine and paracrine mechanisms. CCN4 is a potential target in combination with immune checkpoint blockade therapy. Knockout of CCN4 reduces tumor growth and increases overall survival only in immunocompetent mice.CCN4 suppresses antitumor immunity by promoting CCL2 and CXCL1 secretion, leading to increased MDSC infiltration.CCN4 suppresses IFN‐γ release by CD8+ T cells through a paracrine mechanism resulting in lower CD45+ cell numbers.Knockout of CCN4 complements immune checkpoint blockade therapy. [ABSTRACT FROM AUTHOR]

Purpose: Study objectives were to examine: (a) biomarker trajectories (change from presurgical baseline values of Lymphedema index (L‐Dex) units and arm volume difference) and symptom cluster scores 24 months after breast cancer surgery and (b) associations of these objective biomarkers and symptom cluster scores. Patient/treatment characteristics influencing trajectories were also evaluated. Methods: A secondary analysis of data from the published interim analysis of a randomized parent study was undertaken using trajectory analysis. Five hundred and eight participants included in the prior analysis with 24 months of postsurgical follow‐up were initially measured with bioelectric impedance spectroscopy (BIS) and tape measure (TM) and completed self‐report measures. Patients were reassessed postsurgery for continuing eligibility and then randomized to either BIS or TM groups and measured along with self‐report data at regular and optional* visits 3, 6,12,15*,18, 21*, and 24‐months. Results: Three subclinical trajectories were identified for each biomarker (decreasing, stable, increasing) and symptom cluster scores (stable, slight increase/decrease, increasing). Subclinical lymphedema was identified throughout the 24‐month period by each biomarker. An L‐Dex increase at 15 months in the BIS group was noted. The self‐report sets demonstrated contingency coefficients of 0.20 (LSIDS‐A soft tissue, P =.031) and 0.19 (FACTB+4, P =.044) with the L‐Dex unit change trajectories. Conclusions: These data support the need for long‐term (24 months) prospective surveillance with frequent assessments (every 3 months) at least 15 months after surgery. Statistically significant convergence of symptom cluster scores with L‐Dex unit change supports BIS as beneficial in the early identification of subclinical lymphedema. [ABSTRACT FROM AUTHOR]

Abstract: Background: Breast cancer patients report a perception of increased muscle fatigue, which can persist following surgery and standardized therapies. In a clinical experiment, we tested the hypothesis that pathways regulating skeletal muscle fatigue are down‐regulated in skeletal muscle of breast cancer patients and that different muscle gene expression patterns exist between breast tumour subtypes. In a preclinical study, we tested the hypothesis that mammary tumour growth in mice induces skeletal muscle fatigue and that overexpression of the cytokine interleukin‐15 (IL‐15) can attenuate mammary tumour‐induced muscle fatigue. Methods: Early stage non‐metastatic female breast cancer patients (n = 14) and female non‐cancer patients (n = 6) provided a muscle biopsy of the pectoralis major muscle during mastectomy, lumpectomy, or breast reconstruction surgeries. The breast cancer patients were diagnosed with either luminal (ER+/PR+, n = 6), triple positive (ER+/PR+/Her2/neu+, n = 5), or triple negative (ER−/PR−/Her2/neu−, n = 3) breast tumours and were being treated with curative intent either with neoadjuvant chemotherapy followed by surgery or surgery followed by standard post‐operative therapy. Biopsies were used for RNA‐sequencing to compare the skeletal muscle gene expression patterns between breast cancer patients and non‐cancer patients. The C57BL/6 mouse syngeneic mammary tumour cell line, E0771, was used to induce mammary tumours in immunocompetent mice, and isometric muscle contractile properties and fatigue properties were analysed following 4 weeks of tumour growth. Results: RNA‐sequencing and subsequent bioinformatics analyses revealed a dysregulation of canonical pathways involved in oxidative phosphorylation, mitochondrial dysfunction, peroxisome proliferator‐activated receptor signalling and activation, and IL‐15 signalling and production. In a preclinical mouse model of breast cancer, the rate of muscle fatigue was greater in mice exposed to mammary tumour growth for 4 weeks, and this greater muscle fatigue was attenuated in transgenic mice that overexpressed the cytokine IL‐15. Conclusions: Our data identify novel genes and pathways dysregulated in the muscles of breast cancer patients with early stage non‐metastatic disease, with particularly aberrant expression among genes that would predispose these patients to greater muscle fatigue. Furthermore, we demonstrate that IL‐15 overexpression can attenuate muscle fatigue associated with mammary tumour growth in a preclinical mouse model of breast cancer. Therefore, we propose that skeletal muscle fatigue is an inherent consequence of breast tumour growth, and this greater fatigue can be targeted therapeutically. [ABSTRACT FROM AUTHOR]

Objective To define a pharmacodynamic biomarker based on gene expression in skin that would provide a biologic measure of the extent of disease in patients with diffuse cutaneous systemic sclerosis (dcSSc) and could be used to monitor skin disease longitudinally. Methods Skin biopsy specimens obtained from a cohort of patients with dcSSc (including longitudinal specimens) were analyzed by microarray. Expression of genes correlating with the modified Rodnan skin thickness score (MRSS) were examined for change over time using a NanoString platform, and a generalized estimating equation (GEE) was used to define and validate longitudinally measured pharmacodynamic biomarkers composed of multiple genes. Results Microarray analysis of genes parsed to include only those correlating with the MRSS revealed prominent clusters of profibrotic/transforming growth factor β-regulated, interferon-regulated/proteasome, macrophage, and vascular marker genes. Using genes changing longitudinally with the MRSS, we defined 2 multigene pharmacodynamic biomarkers. The first was defined mathematically by applying a GEE to longitudinal samples. This modeling method selected cross-sectional THBS1 and longitudinal THBS1 and MS4A4A. The second model was based on a weighted selection of genes, including additional genes that changed statistically significantly over time: CTGF, CD163, CCL2, and WIF1. In an independent validation data set, biomarker levels calculated using both models correlated highly with the MRSS. Conclusion Skin gene expression can be used effectively to monitor changes in SSc skin disease over time. We implemented 2 relatively simple models on a NanoString platform permitting highly reproducible assays that can be applied directly to samples from patients or collected as part of clinical trials. [ABSTRACT FROM AUTHOR]

BACKGROUND Biomarkers are routinely used to predict responses to systemic therapies, but their utility for predicting responses to local therapy for breast cancer is not known. This study determined whether biomarkers could predict responses to breast-conserving therapy (BCT) and mastectomy. METHODS A review of the Surveillance, Epidemiology, and End Results database identified women diagnosed with early-stage invasive ductal breast cancer and treated with BCT or mastectomy from 1998 to 2008. The estrogen receptor (ER) status and the histologic grade were used to construct 3 biomarker profiles: low risk (ER-positive, low/intermediate grade), intermediate risk (ER-positive, high grade), and high risk (ER-negative, any grade). The primary measured outcome was disease-specific survival (DSS). RESULTS BCT and mastectomy were performed in 114,486 patients (59.2%) and 79,035 patients (40.8%), respectively. There were 122,420 low-risk patients (63.3%), 34,341 intermediate-risk patients (17.7%), and 36,760 high-risk patients (19.0%). Multivariate analyses were performed separately for patients with low-, intermediate-, and high-risk tumors. The adjusted hazard ratios for DSS for patients who underwent mastectomy versus BCT for low-, intermediate-, and high-risk tumors were 1.66 (95% confidence interval [CI], 1.54-1.79; P < .001), 1.40 (95% CI, 1.29-1.53; P < .001), and 1.27 (95% CI, 1.19-1.35; P < .001), respectively. CONCLUSIONS Patients with ER-positive, low-grade breast cancers who underwent mastectomy had a 66% increase in disease-specific mortality versus those who underwent BCT. Biomarker profiles defined by the ER status and grade may improve the selection of local therapy for breast cancer. Cancer 2015;121:2705-2712. © 2015 American Cancer Society [ABSTRACT FROM AUTHOR]

The article discusses a study on the cost-effectiveness of preoperative magnetic resonance imaging (MRI) in selecting patients for prophylactic mastectomy (PM) with or without sentinel lymph node biopsy (SLNB). Six hundred-thirteen PMs were performed in 529 study population between January 1999 and January 2006. Such a surgical operation is frequently recommended as an alternative to intensive screening for patients with known mutations of the BRCA1 or BRCA2 genes. Characteristics of patients who underwent PM with or without SLNB are also cited.

The effects of fetal cocaine exposure on newborn cry characteristics were studied in 80 cocaine-exposed and 80 control infants. The groups were stratified to be similar on maternal demographic characteristics and maternal use of other illegal substances and alcohol during pregnancy. The hypothesis was that excitable cry characteristics were related to the direct effects of cocaine, while depressed cry characteristics were related to the indirect effects of cocaine secondary to low birthweight. Structural equation modeling (EQS) showed direct effects of cocaine on cries with a longer duration, higher fundamental frequency, and a higher and more variable first formant frequency. Indirect effects of cocaine secondary to low birthweight resulted in cries with a longer latency, fewer utterances, lower amplitude, and more dysphonation. Cocaine-exposed infants had a lower birthweight, shorter length, and smaller head circumference than the unexposed controls. Findings were consistent with the notion that 2 neurobehavioral syndromes, excitable and depressed, can be described in cocaine-exposed infants, and that these 2 syndromes are due, respectively, to direct neurotoxic effects and indirect effects secondary to intrauterine growth retardation. [ABSTRACT FROM PUBLISHER]