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* Context.--Mitochondria and mitochondrial DNA have been suggested to play a role in cancer initiation and progression. Knowledge of mitochondrial DNA could provide a breakthrough to advance cancer management. Objective.--To identify the mitochondrial DNA landscape in non-small cell lung carcinoma. Design.--The adenocarcinoma set consisted of 365 pairs of adenocarcinomas and normal lung tissues, whereas the metastasis set included 12 primary non-small cell carcinomas, 15 metastatic tumors, and their normal counterparts. Tumor-specific somatic variants were identified, and if a variant showed heteroplasmy, the proportion of minor alleles was evaluated. Variants with greater than 10% change in allele frequency between tumor and normal pairs were identified as 'heteroplasmic shifts.' Results.--Tumor-specific variants appeared throughout the whole mitochondrial genome, without a common hot spot. Distinct variant profiles were seen in 289 (79.18%) of all individual adenocarcinomas. The presence of a unique profile and the number and loading of heteroplasmic shifts in tumors increased with higher stage or lymph node metastasis, and were related to shorter survival. In the metastasis set, the primary tumor variants were generally found in metastatic tumors. Conclusions.--This study shows that somatic mitochondrial DNA mutations present with diverse locations and unique profiles in each individual tumor, implying their clinicopathologic utility. doi: 10.5858/arpa.2022-0175-OA, Alongside conventional studies investigating cancer genetics, interest in mitochondrial DNA (mtDNA) is increasing, with the anticipation that it will provide a genetic breakthrough. (1-8) Mitochondria perform several key functions, such [...]

In low-dose cone beam computed tomography (CT), the insufficient number of photons inevitably results in noise, which reduces the accuracy of disease diagnosis. One approach to improving the image quality of CT images acquired using a low-dose protocol involves the utilization of a reconstruction algorithm that efficiently reduces noise. In this study, we modeled the Feldkamp–Davis–Kress (FDK) algorithm using various filters and projection angles and applied it to the reconstruction process using CT simulation. To quantitatively evaluate the quality of the reconstruction images, we measured the coefficient of variation (COV), and signal-to-noise ratio (SNR) in the air, brain, and bone regions to evaluate the noise level. Furthermore, we calculated root mean square error (RMSE), universal image quality index (UQI), and blind/referenceless image spatial quality evaluator (BRISQUE) as similarity and no-reference evaluation. The Hann filter of the FDK algorithm showed superior performance in terms of COV, SNR, RMSE, and UQI compared to the other filters. In addition, when analyzing the COV and SNR results, we observed that image quality increased significantly at projection angles smaller than approximately 2.8°. Moreover, based on BRISQUE results, we confirm that the Shepp–Logan filter exhibited the most superior performance. In conclusion, we believe that the application of the Hann filter in the FDK reconstruction process offers significant advantages in improving the image quality acquired under a low-dose protocol, and we expect that our study will be a preliminary study of no-reference evaluation of CT reconstruction images. [ABSTRACT FROM AUTHOR]

Noise in computed tomography (CT) is inevitably generated, which lowers the accuracy of disease diagnosis. The non-local means approach, a software technique for reducing noise, is widely used in medical imaging. In this study, we propose a noise reduction algorithm based on fast non-local means (FNLMs) and apply it to CT images of a phantom created using 3D printing technology. The self-produced phantom was manufactured using filaments with similar density to human brain tissues. To quantitatively evaluate image quality, the contrast-to-noise ratio (CNR), coefficient of variation (COV), and normalized noise power spectrum (NNPS) were calculated. The results demonstrate that the optimized smoothing factors of FNLMs are 0.08, 0.16, 0.22, 0.25, and 0.32 at 0.001, 0.005, 0.01, 0.05, and 0.1 of noise intensities, respectively. In addition, we compared the optimized FNLMs with noisy, local filters and total variation algorithms. As a result, FNLMs showed superior performance compared to various denoising techniques. Particularly, comparing the optimized FNLMs to the noisy images, the CNR improved by 6.53 to 16.34 times, COV improved by 6.55 to 18.28 times, and the NNPS improved by 10−2 mm2 on average. In conclusion, our approach shows significant potential in enhancing CT image quality with anthropomorphic phantoms, thus addressing the noise issue and improving diagnostic accuracy. [ABSTRACT FROM AUTHOR]

The aim of this research is to make a cross-national comparison of art curricula for kindergarten-aged children across five countries--Korea, Norway, New Zealand, Slovakia and Singapore. A document analysis was conducted on the five curricula using a constant comparative approach for selected qualitative statements to analyse two major constructs: "art within the curriculum system" and the "educational value of art". Only two countries expressly mentioned art education in the overall aims of their curricula document. All five countries included art education as part of an interdisciplinary learning area. The goals of art education were primarily concerned with art expression in the affective domain. The content of art education identified in the curriculum documents was related mainly to expression. Guidance on assessment of art education was lacking in most countries. While the value of art was recognized by all countries, art education did not appear to have enough attention or recognition in the "general aims" of the curricula. Governments should give greater consideration to the value of art education to maximize its many positive effects on children.

Small molecule fluorophores often face challenges such as short blood half-life, limited physicochemical and optical stability, and poor pharmacokinetics. To overcome these limitations, we conjugated the zwitterionic near-infrared fluorophore ZW800-PEG to human serum albumin (HSA), creating HSA-ZW800-PEG. This conjugation notably improves chemical, physical, and optical stability under physiological conditions, addressing issues commonly encountered with small molecules in biological applications. Additionally, the high molecular weight and extinction coefficient of HSA-ZW800-PEG enhances biodistribution and tumor targeting through the enhanced permeability and retention effect. The unique distribution and elimination dynamics, along with the significantly extended blood half-life of HSA-ZW800-PEG, contribute to improved tumor targetability in both subcutaneous and orthotopic xenograft tumor-bearing animal models. This modification not only influences the pharmacokinetic profile, affecting retention time and clearance patterns, but also enhances bioavailability for targeting tissues. Our study guides further development and optimization of targeted imaging agents and drug-delivery systems. [ABSTRACT FROM AUTHOR]

The assembly of 30S ribosomes requires the precise addition of 20 proteins to the 16S ribosomal RNA. How early binding proteins change the ribosomal RNA structure so that later proteins may join the complex is poorly understood. Here we use single-molecule fluorescence resonance energy transfer (FRET) to observe real-time encounters between Escherichia coli ribosomal protein S4 and the 16S 5' domain RNA at an early stage of 30S assembly. Dynamic initial S4-RNA complexes pass through a stable non-native intermediate before converting to the native complex, showing that non-native structures can offer a low free-energy path to protein-RNA recognition. Three-colour FRET and molecular dynamics simulations reveal how S4 changes the frequency and direction of RNA helix motions, guiding a conformational switch that enforces the hierarchy of protein addition. These protein-guided dynamics offer an alternative explanation for induced fit in RNA-protein complexes., The ribosome is a large cellular complex that synthesizes proteins. During assembly of the small (30S) subunit of the E. coli ribosome, 20 ribosomal proteins associate with the 16S ribosomal [...]