Cancer screening through surface-enhanced Raman spectroscopy fingerprinting analysis of urinary metabolites using surface-carbonized silver nanowires on a filter membrane.

BACKGROUND: Label-free surface-enhanced Raman spectroscopy (SERS)-based metabolic profiling has great potential for early cancer diagnosis, but further advancements in analytical methods and clinical evidence studies are required for clinical applications. To improve the cancer diagnostic accuracy of label-free SERS spectral analysis of complex biological fluids, it is necessary to obtain specifically enhanced SERS signals of cancer-related metabolites present at low concentrations. RESULTS: This study presents a novel 3D SERS sensor, comprising a surface-carbonized silver nanowire (AgNW)-stacked filter membrane, alongside an optimized urine/methanol/chloroform extraction technique, which specifically changes the molecular adsorption and orientation of aromatic metabolites onto SERS substrates. By analyzing the pretreated urine samples on the surface-carbonized AgNW 3D SERS sensor, distinct and highly enhanced SERS peaks derived from semi-polar aromatic metabolites were observed for pancreatic cancer and prostate cancer samples compared with normal controls. Urine metabolite analysis using SERS fingerprinting successfully differentiated pancreatic cancer and prostate cancer groups from normal control group: normal control (n = 56), pancreatic cancer (n = 40), and prostate cancer (n = 39). SIGNIFICANCE AND NOVELTY: We confirmed the clinical feasibility of performing fingerprint analysis of urinary metabolites based on the surface-carbonized AgNW 3D SERS sensor and methanol/chloroform extraction for noninvasive cancer screening. This technology holds potential for large-scale screening owing to its high accuracy, and cost effective, simple and rapid detection method.

Exploring the nexus between physical environments, resident preferences, and usage frequency of community centers: Evidence from two Korean neighborhoods in Seoul.

Community centers offer a public space for physical activities, attracting residents with diverse interests and abilities, and promoting social interaction and connection, which in turn enhances individuals' physical and mental fitness and fosters a sense of community. When exploring the correlation between community space accessibility and usage frequency, it is crucial to consider empirical evidence and resident preferences. Nevertheless, the role of physical environments in determining community center usage frequency, while also considering residents' inclination for effortless access, remains unclear. This study investigated the impact of resident preferences and satisfaction with the accessibility of community centers and physical environments on usage frequency, addressing a gap in previous research. Structural equation models were utilized to analyze a household drop-off survey consisting of 186 residents gathered from two neighborhoods in Korea. The results revealed that while the preference for easy access to community centers did not have a substantial effect on their usage frequency, satisfaction with easy access to such centers was positively linked to usage frequency. Furthermore, the perception of physical environments as being walkable and having a diverse range of amenities was associated with a higher frequency of community center usage. These findings have policy implications as they can help increase the usage frequency of community centers and enhance overall well-being in regenerated neighborhoods.

Effects of Multifaceted Determinants on Individual Stress: The Mediating Role of Social Capital.

Stress substantially results in various negative health outcomes. While there is a nexus between social capital and individual stress, previous studies have primarily explored the direct relationship between them. Social capital may potentially have an indirect effect on perceived stress via social networking pathways that provide accessible resources. This study addresses this research gap by exploring the mediating effect of social capital for associations between personal-level features, personal-level behaviors, physical environments, and perceived stress. A household drop-off survey of 600 respondents was collected from two neighborhoods in Korea and analyzed by structural equation models. Results showed that social capital acted as a mediator on perceived stress level. The frequency of community center use had both direct and indirect impacts on stress level through social capital. Those who were satisfied with the cleanliness of the neighborhood had a higher level of social capital and a lower level of stress indirectly through social capital. Households with more children had a lower level of social capital, while persons who had chronic disease and were more extroverted, agreeable, and open to others enjoyed a higher level of social capital. The results provide policy implications on how community revitalization affects social capital and perceived stress.

Rapid and sensitive multiplex molecular diagnosis of respiratory pathogens using plasmonic isothermal RPA array chip.

The current clinically available multiplex molecular diagnostic technologies are difficult to apply to onsite diagnostic platforms due to their large and sophisticated instrumentation, long amplification times and limited number of simultaneous detections. We developed a plasmonic isothermal recombinase polymerase amplification (RPA) array chip for rapid and sensitive multiplex molecular detection. The 3D plasmonic substrate composed of Au nanoparticles (NPs) on dense Au nanopillars (NPOP) showed highly enhanced plasmon-enhanced fluorescence (PEF) of RPA products with long DNA amplicons (~200 bp). The plasmonic 4-plex RPA array chip successfully detected bacterial DNA within 30 min and viral RNA within 40 min; the sensitivity of the plasmonic RPA array chip was comparable to or 10-fold higher than that of the 4-pelx liquid-phase RPA and 4-plex liquid-phase PCR techniques. Additionally, no cross-reactivity was observed. The 4-plex plasmonic RPA array chip was preliminary evaluated using clinical respiratory viral-positive nasopharyngeal swab samples. This approach enables rapid, sensitive and high-multiplex molecular detection and can be used in the realization of a simplified and miniaturized platform for onsite multiplex molecular diagnostics.

Label-Free SERS Analysis of Urine Using a 3D-Stacked AgNW-Glass Fiber Filter Sensor for the Diagnosis of Pancreatic Cancer and Prostate Cancer.

Metabolomics shows tremendous potential for the early diagnosis and screening of cancer. For clinical application as an effective diagnostic tool, however, improved analytical methods for complex biological fluids are required. Here, we developed a reliable rapid urine analysis system based on surface-enhanced Raman spectroscopy (SERS) using 3D-stacked silver nanowires (AgNWs) on a glass fiber filter (GFF) sensor and applied it to the diagnosis of pancreatic cancer and prostate cancer. Urine samples were pretreated with centrifugation to remove large debris and with calcium ion addition to improve the binding of metabolites to AgNWs. The label-free urine-SERS detection using the AgNW-GFF SERS sensor showed different spectral patterns and distinguishable specific peaks in three groups: normal control (n = 30), pancreatic cancer (n = 22), and prostate cancer (n = 22). Multivariate analyses of SERS spectra using unsupervised principal component analysis and supervised orthogonal partial least-squares discriminant analysis showed excellent discrimination between the pancreatic cancer group and the prostate cancer group as well as between the normal control group and the combined cancer groups. The results demonstrate the great potential of the urine-SERS analysis system using the AgNW-GFF SERS sensor for the noninvasive diagnosis and screening of cancers.

Highly sensitive and repeatable DNA-SERS detection system using silver nanowires-glass fiber filter substrate.

This paper describes a new simple DNA detection method based on surface-enhanced Raman scattering (SERS) technology using a silver nanowire stacked-glass fiber filter substrate. In this system, DNA-intercalating dye (EVAGreen) and reference dye (ROX) are used together to improve the repeatability and reliability of the SERS signals. We found that the SERS signal of EVAGreen was reduced by intercalation into DNA amplicons of a polymerase chain reaction on the silver nanowire stacked-glass fiber filter substrate, whereas that of ROX stayed constant. The DNA amplicons could be quantified by correcting the EVAGreen-specific SERS signal intensity with the ROX-specific SERS signal intensity. Multivariate analysis by partial least square methods was also successfully performed. And we further applied it to loop-mediated isothermal amplification with potential use for on-site diagnostics. The sensitivities of the DNA-SERS detection showed about 100 times higher than those of conventional fluorescence-based detection methods. The DNA-SERS detection method can be applied to various isothermal amplification methods, which is expected to realize on-site molecular diagnostics with high sensitivity, repeatability, simplicity, affordability, and convenience.

Does elderly safety matter? Associations between built environments and pedestrian crashes in Seoul, Korea.

Korea's elderly population is growing rapidly, as is attention to elderly pedestrian safety. Despite a consensus that the elderly are vulnerable to pedestrian safety issues, our understanding of the determinants of elderly pedestrian crashes is limited. This study explores which attributes of the built environment affect the risk of pedestrian accidents among the elderly, particularly with respect to injury severity, in Seoul, Korea. We compare the impacts of various determinants on pedestrian crashes to specify how the associations between various built environments and pedestrian accidents differ by pedestrian age. We also examine how the associations vary by neighborhood economic attributes. Our findings provide policy implications for identifying various attributes of the built environment that increase the risk of elderly pedestrian crashes and improving the safety of elderly pedestrian by neighborhood economic status.

Author Correction: Closed-type pre-treatment device for point-of-care testing of sputum.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Closed-type pre-treatment device for point-of-care testing of sputum.

The procedures and protocols for the pre-treatment of sputum specimens, mainly used for the diagnosis of pneumonia, are complex, labor intensive, and require skilled specialists working in a biosafety containment laboratory because of sample infectivity. In this study, we developed the first portable, low-power pre-treatment device that carries out all sputum pre-treatment procedures (liquefaction, homogenization, dissolution, and inactivation) in an enclosed space. Designed to simultaneously employ chemical and mechanical dissolution in the enclosed chamber, this device eliminates the risk of transmission and improves the effectiveness of sputum dissolution and pathogen detection. This device is expected to allow for the pre-treatment of infectious sputum specimens outside of a biosafety containment laboratory. Used in conjunction with automated genome extraction and detection systems, this device should make the on-site diagnosis using infectious sputum specimens possible.

The Impacts of Residential Segregation on Obesity.

BACKGROUND: This study examined the association between residential segregation and obesity for Whites, African Americans, Hispanics, and Asians. This study considered 3 dimensions of residential segregation, isolation, dissimilarity, and concentration. METHODS: By combining individual-level data from the Behavioral Risk Factor Surveillance System and county-level data from the County Health Rankings and Roadmaps, the total sample size was 204,610 respondents (160,213 Whites, 21,865 African Americans, 18,027 Hispanics, and 4505 Asians) from 205 counties in the United States. Two-level logistic regression models were performed. RESULTS: African Americans and Hispanics in counties with high levels of isolation, dissimilarity, and concentration were more likely to be obese; these relationships did not hold true for Whites and Asians. Counties with a higher percentage of populations with the income below the poverty line and a higher percentage of fast food restaurants in the county were associated with a higher likelihood of obesity for all racial/ethnic groups. African Americans and Hispanics with low levels of education and income were more likely to be obese. CONCLUSIONS: Residential segregation had a contextual influence on weight status, and the context of counties influenced racial/ethnic groups differently. Obesity reduction programs should consider the contextual influence on minority populations and target subgroups living in highly segregated areas.

Silicon membrane filter designed by fluid dynamics simulation and near-field stress analysis for selective cell enrichment.

Selective cell enrichment technologies can play an important role in both diagnostic and therapeutic areas. However, currently used cell sorting techniques have difficulties in rapidly isolating only the desired target cells from a large volume of body fluids. In this work, we developed a filtering system that can quickly separate and highly concentrate cells from a large volume of solution, depending on their size, using a silicon membrane filter. To overcome the problems caused by material limitations of the brittle silicon, we designed a novel membrane filter with various pore designs. From these designs, the most optimal design with high pore density, while preventing crack formation was derived by applying fluid dynamics simulation and near-field stress analysis. The membrane filter system using the selected design was fabricated, and cell filtration performance was evaluated. The LNCaP cell in horse blood was recovered up to 86% and enriched to 187-fold compared to initial cell populations after filtration at a flow rate of 5 mL/min. The results demonstrate that the filter presented in this study can rapidly and selectively isolate target cells from a large volume of body fluid sample.

From Perception to Action: The Mediating Role of Parental Safety Concerns on Adolescents' Physical Activity.

BACKGROUND: Parental safety concerns have been recognized as a critical determinant of adolescents' physical activity. However, it is still uncertain what factors relate to parental safety concern, and how they, in turn, affect adolescents' physical activity. This study explored the mediating relationships of parental safety concern on adolescents' physical activity by considering personal, social, and built environmental factors. METHODS: This cross-sectional analysis used the data from Growing Up in Ireland (GUI), a national study (N = 5212). A structural equation model (SEM) was used to evaluate the hypothesized framework. RESULTS: 50% of the adolescents engaged in at least 6 days of exercise every 14 days, at a rate of at least 20-minutes per day. Adolescents were more physically active when parents perceived higher levels of safety. Parents perceived their children as safe when they lived in areas with easy access to play spaces. Moreover, adolescents with more close friends and more friends with whom they could play were more physically active and their parents perceived higher levels of safety. CONCLUSIONS: Parental safety concerns may profoundly affect adolescent's physical activity and the resulting health outcomes. Programs and policies should consider the importance of parental safety concerns in promoting adolescents' physical activity.