Evidence for the potent influence of stromal organization and function on invasion and metastasis of breast tumors is ever growing. We have performed a rigorous examination of the relationship of a tumor-associated collagen signature-3 (TACS-3) to the long-term survival rate of human patients. TACS-3 is characterized by bundles of straightened and aligned collagen fibers that are oriented perpendicular to the tumor boundary. An evaluation of TACS-3 was performed in biopsied tissue sections from 196 patients by second harmonic generation imaging of the backscattered signal generated by collagen. Univariate analysis of a Cox proportional hazard model demonstrated that the presence of TACS-3 was associated with poor disease-specific and disease-free survival, resulting in hazard ratios between 3.0 and 3.9. Furthermore, TACS-3 was confirmed to be an independent prognostic indicator regardless of tumor grade and size, estrogen or progesterone receptor status, human epidermal growth factor receptor-2 status, node status, and tumor subtype. Interestingly, TACS-3 was positively correlated to expression of stromal syndecan-1, a receptor for several extracellular matrix proteins including collagens. Because of the strong statistical evidence for poor survival in patients with TACS, and because the assessment can be performed in routine histopathological samples imaged via second harmonic generation or using picrosirius, we propose that quantifying collagen alignment is a viable, novel paradigm for the prediction of human breast cancer survival.

Aligned collagen is a prognostic signature for survival in human breast carcinoma.

Second-harmonic generation (SHG) microscopy has emerged as a powerful modality for imaging fibrillar collagen in a diverse range of tissues. Because of its underlying physical origin, it is highly sensitive to the collagen fibril/fiber structure, and, importantly, to changes that occur in diseases such as cancer, fibrosis and connective tissue disorders. We discuss how SHG can be used to obtain more structural information on the assembly of collagen in tissues than is possible by other microscopy techniques. We first provide an overview of the state of the art and the physical background of SHG microscopy, and then describe the optical modifications that need to be made to a laser-scanning microscope to enable the measurements. Crucial aspects for biomedical applications are the capabilities and limitations of the different experimental configurations. We estimate that the setup and calibration of the SHG instrument from its component parts will require 2-4 weeks, depending on the level of the user's experience.

Second harmonic generation microscopy for quantitative analysis of collagen fibrillar structure

Photochromic organic–inorganic hybrid materials have attracted considerable attention owing to their potential application in photoactive devices, such as optical memories, windows, photochromic decorations, optical switches, filters or non-linear optics materials. The growing interest in this field has largely expanded the use of photochromic materials for the purpose of improving existing materials and exploring new photochromic hybrid systems. This tutorial review summarizes the design and preparation of photochromic hybrid materials, and particularly those based on the incorporation of organic molecules in organic–inorganic matrices by the sol–gel method. This is the most commonly used method for the preparation of these materials as it allows vitreous hybrid materials to be obtained at low temperatures, and controls the interaction between the organic molecule and its embedding matrix, and hence allows tailoring of the performance of the resulting devices.

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Photochromic organic-inorganic hybrid materials.

Although paper electronics is a compelling concept, the large surface roughness and opaqueness of most paper substrates has hindered its development from a dormant idea to a thriving technology. A recent demonstration of transparent paper with nanoscale surface roughness has revived an interest in using renewable cellulose substrates for electronics and optoelectronics. In this short review, we will first summarize the recent progress of transparent paper electronics through structure engineering. We will also discuss the properties and functionalization of transparent paper, such as surface roughness, printability, thermal stability, etc. Finally, we will summarize the recent achievements on proof-of-concepts of transparent paper, which pave the way for next-generation green electronics fabricated with roll-to-roll printing methods. Advantages of transparent paper over traditional flexible plastic substrates and its challenges will also be discussed.

Transparent paper: fabrications, properties, and device applications

https://cyberleninka.org/article/n/1310744.pdf

Poly(amidoamine), polypropylenimine, and related dendrimers and dendrons possessing different 1 → 2 branching motifs : An overview of the divergent procedures

Triboelectric nanogenerators (TENGs) have attracted increasing attention because of their excellent energy conversion efficiency, the diverse choice of materials, and their broad applications in energy harvesting devices and self-powered sensors. New materials have been explored, including green materials, but their performances have not yet reached the level of that for fluoropolymers. Here, a high-performance, fully green TENG (FG-TENG) using cellulose-based tribolayers is reported. It is shown that the FG-TENG has an output power density of above 300 W m-2 , which is a new record for green-material-based TENGs. The high performance of the FG-TENG is due to the high positive charge density of the regenerated cellulose. The FG-TENG is stable after more than 30 000 cycles of operations in humidity of 30%-84%. This work demonstrates that high-performance TENGs can be made using natural green materials for a broad range of applications.

/pdf/cellulose-based-fully-green-triboelectric-nanogenerators-1fkbz5yfjd.pdf

Cellulose‐Based Fully Green Triboelectric Nanogenerators with Output Power Density of 300 W m−2

Characteristic changes in the organization of fibrillar collagen can potentially serve as an early diagnostic marker in various pathological processes. Tissue types containing collagen I can be probed by pulsed high-intensity laser radiation, thereby generating second harmonic light that provides information about the composition and structure at a microscopic level. A technique was developed to determine the essential second harmonic generation (SHG) parameters in a laser scanning microscope setup. A rat-tail tendon frozen section was rotated in the xy-plane with the pulsed laser light propagating along the z-axis. By analyzing the generated second harmonic light in the forward direction with parallel and crossed polarizer relative to the polarization of the excitation laser beam, the second-order nonlinear optical susceptibilities of the collagen fiber were determined. Systematic variations in SHG response between ordered and less ordered structures were recorded and evaluated. A 500µm-thick z-cut lithiumniobate (LiNbO3) was used as reference. The method was applied on frozen sections of malignant melanoma and normal skin tissue. Significant differences were found in the values of d22, indicating that this parameter has a potential role in differentiating between normal and pathological processes.

/pdf/quantification-of-the-second-order-nonlinear-susceptibility-3gvg1g74c9.pdf

Jonas Örtegren

Papers

Cellulose‐Based Fully Green Triboelectric Nanogenerators with Output Power Density of 300 W m−2

Quantification of the second-order nonlinear susceptibility of collagen I using a laser scanning microscope.

Paper Surfaces for Metal Nanoparticle Inkjet Printing

Surface dilatational properties of mixed sodium dodecyl sulfate/dodecanol solutions

Interaction of the human body with triboelectric nanogenerators