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For patients with nonpalpable breast lesions, breast-conserving surgery can be performed to remove the primary lesion while leaving as much normal breast tissue as possible. To perform breast-conserving surgery, localization tools are required to indicate such lesions’ location. Conventional localization tools such as wire-guided localization (WGL) lead to a high reexcision rate. A magnetic detection system reduces the reexcision rate by providing objective information about the marker’s location. In this study, we numerically evaluated the induced magnetic field strength from the magnetic marker from all orientations and found an optimal design achieving 100% detection at 40 mm distance from all orientations. Two marker samples are fabricated, and the experimentally detectable magnetic field strength is compared with the numerical simulation results. Both data show similar trends, thus validating the numerical simulation. The application of premagnetization on the magnetic markers are also evaluated. With the use of premagnetization, magnetic markers with 0.6 mm diameter can be detected in 46 mm distance, exceeding existing commercialized magnetic markers. [ABSTRACT FROM AUTHOR]

To excise the non-palpable breast lesion, conventionally surgeons estimate the excision margin by naked eyes subjectively with a localization tool such as a hook wire. By introducing a magnetic detection system, location of the magnetic marker injected intratumorally can be identified with a handheld magnetic probe. Detection ranges of existing magnetic markers are up to 30 mm, limiting applications on tumors located deeper down the skin. In this study, materials and designs of magnetic markers are evaluated to achieve an extended detection range. Stainless steel (SUS) 304 is magnetic and biocompatible for an implant device, and a SQUID measurement is performed to evaluate its magnetic properties. A numerical simulation tool has been developed to evaluate the magnetic field strength induced by the magnetic marker from any orientation. Based on a backward-facing hook shape design, magnetic field strength induced by the marker with varies hook length and separation angle between the hook and the main body is evaluated. At an extended distance of 40 mm, the detection of the magnetic marker with 8 mm hook length and 75° separation angle can be achieved on 57% of the orientations. [ABSTRACT FROM AUTHOR]

BACKGROUND: Docetaxel is a yew compound antitumor agent with accurate antitumor efficacy, but its application is limited due to the high and serious adverse effects, and finding effective combination therapy options is a viable strategy. Immune checkpoint inhibitors have become hotspots in enhancing anti-tumor immunity by blocking immune checkpoint signaling pathways, but their response rate to monotherapy use is not high and the efficacy is minimal. OBJECTIVE: To explore the anti-tumor effects and mechanisms of the combination of PD-1 inhibitors and Docetaxel through in vivo experiments and develop a feasible combination treatment for the therapy of prostate cancer. METHODS: Tumor-bearing mice were subcutaneously injected with 0.1 ml RM-1 cells. Treatment were taken when the tumor growed up to 3 mm, after which the tumor and spleen were removed to test the antitumor effect with Flow cytometric (FACS) analysis, Immunohistochemistry, Western Blot. RESULTS: In this experiment, we found that PD-1 inhibitors combined with Docetaxel had a synergistic effect on mouse prostate cancer, inhibited the growth of prostate cancer, improved survival and reduced adverse reactions, increased spleen and tumor infiltrative CD4+ and CD8+ T cells, especially in group combination with low-dose Docetaxel, and were related to the PI3K/AKT/NFKB-P65/PD-L1 signaling pathway. CONCLUSION: Our study confirms that PD-1 inhibitors in combination with Docetaxel are a viable combination strategy and provide a safe and effective combination option for the clinical treatment of prostate cancer. [ABSTRACT FROM AUTHOR]

Abdominal aortic aneurysms (AAA) are associated with systemic inflammation and endothelial dysfunction. We previously reported flow mediated dilatation (FMD) of the brachial artery as a predictor of AAA growth. We hence hypothesised that other physical characteristics of the brachial artery correlate with AAA growth. Using a prospectively cohort of AAA patients, we devised a 'brachial artery relaxation index' (BARI) and examined its role as a biomarker for AAA growth. However, no correlation between BARI and future aneurysm growth was observed (p = 0.45). Therefore, our investigations did not substantiate the hypothesis that other physical characteristics of the brachial artery predicts AAA growth. [ABSTRACT FROM AUTHOR]

Early detection of compromised circulation is essential for postoperative monitoring of free flap. Hourly clinical check-ups such as inspection and palpation still result in a delay in detection. Conversely, optical reflection and temperature measurement are useful alternatives for detecting blood circulation. However, conventional methods that verify ischemia and congestion within a short period have not been reported. In this study, we measured short-term changes in optical reflection and temperature in a rat flap using a wearable flexible sensor probe previously developed in our laboratory. Five ischemia and five congestion groin flap models were measured using a sensor probe and reference devices. Curve fitting was performed on transition signals to evaluate changes in signals and their time constants. The optical reflection signal decreased after venous ligation and increased after arterial ligation. The parameters of the fitted curves indicate a significant difference between congestion and ischemia at p < 0.01 (probability value), which was detected within a few minutes after ligation. However, insufficient significance was observed in the temperature signal. Our method gives supporting information to verify ischemia and congestion, and has the potential to rapidly detect compromised circulation. [ABSTRACT FROM AUTHOR]

Arterial spin labeling (ASL) MRI is a non-invasive technique for the quantification of cerebral perfusion, and pseudo-continuous arterial spin labeling (PCASL) has been recommended as the standard implementation by a recent consensus of the community. Due to the low spatial resolution of ASL images, perfusion quantification is biased by partial volume effects. Consequently, several partial volume correction (PVEc) methods have been developed to reduce the bias in gray matter (GM) perfusion quantification. The efficacy of these methods relies on both the quality of the ASL data and the accuracy of partial volume estimates. Here we systematically investigate the sensitivity of different PVEc methods to variability in both the ASL data and partial volume estimates using simulated PCASL data and in vivo PCASL data from a reproducibility study. We examined the PVEc methods in two ways: the ability to preserve spatial details and the accuracy of GM perfusion estimation. Judging by the root-mean-square error (RMSE) between simulated and estimated GM CBF, the spatially regularized method was superior in preserving spatial details compared to the linear regression method (RMSE of 1.2 vs 5.1 in simulation of GM CBF with short scale spatial variations). The linear regression method was generally less sensitive than the spatially regularized method to noise in data and errors in the partial volume estimates (RMSE 6.3 vs 23.4 for SNR = 5 simulated data), but this could be attributed to the greater smoothing introduced by the method. Analysis of a healthy cohort dataset indicates that PVEc, using either method, improves the repeatability of perfusion quantification (within-subject coefficient of variation reduced by 5% after PVEc). [ABSTRACT FROM AUTHOR]