Time-tagged ticker tapes for intracellular recordings

A core taken in a tree today can reveal climate events from centuries past. Here we adapt this idea to record histories of neural activation. We engineered slowly growing intracellular protein fibers which can incorporate diverse fluorescent marks during growth to store linear ticker tape-like histories. An embedded HaloTag reporter incorporated user-supplied HaloTag-ligand dyes, leading to colored stripes whose boundaries mapped fiber growth to wall-clock time. A co-expressed eGFP tag driven by the cFos immediate early gene promoter recorded the history of neural activity. High-resolution multispectral imaging on fixed samples read the cellular histories. We demonstrated recordings of cFos activation in ensembles of cultured neurons with a single-cell absolute accuracy of approximately 39 min over a 12-hour interval. Protein-based ticker tapes have the potential to achieve massively parallel single-cell recordings of multiple physiological modalities.

Ora-Pro-Nóbis: Ampliando os Conhecimentos de sua Utilização na Alimentação a Partir da Educação Alimentar e Nutricional (EAN)

Resumo Alcançar a saudabilidade por meio da mudança dos hábitos alimentares ocupa uma posição de destaque atualmente. Pesquisadores do Mundo todo buscam estudar alimentos alternativos para a manutenção da saúde e até para o tratamento de doenças. Entre os alimentos alternativos surge o Ora-Pro-Nóbis (Pereskia Aculeata Mill.), uma planta alimentícia classificada como hortaliça não convencional, que se destaca por possuir teor elevado de proteína, fibras, vitaminas e sais minerais, além de ser de baixo custo e de fácil cultivo. O presente estudo tem como objetivo apresentar os benefícios da utilização do Ora-Pro-Nóbis na dieta humana, e aprimorar a orientação sobre o seu uso junto aos profissionais da área de nutrição, contribuindo, assim, para a atuação do nutricionista como educador, por meio da prática da “Transposição Didática”. Para o desenvolvimento deste artigo foi realizada uma busca bibliográfica nas bases de dados: Lilacs, SciELO, Medline, Google Acadêmico e Catálogo de Teses e Dissertações da Capes. Esse material poderá ser utilizado como base para o profissional da área de nutrição fazer uma análise comparativa da composição nutricional da hortaliça com outros alimentos convencionais consumidos pela população em geral. Dessa maneira, o educador terá informações que irão contribuir com o “saber ensinar” e a possível ampliação do “saber aprendido” dos educandos, buscando, assim, uma mudança no comportamento alimentar em prol da saúde. Palavras-chave: Alimentos Alternativos. Plantas Alimentícias. Transposição Didática. AbstractAchieving healthiness through changing eating habits occupies a prominent position today. Researchers from all over the world search for alternative foods for the health maintenance and even for the treatment of diseases. Among the alternative foods, Ora-Pro-Nóbis (Pereskia Aculeata Mill.), a food plant classified as non-conventional vegetable, stands out for its high content of protein, fibers, vitamins and mineral salts, besides being of low cost and easy cultivation. This study aims to present the benefits of using Ora-Pro-Nóbis in the human diet, and improve orientation of its use with professionals in the nutrition area, thus contributing to the nutritionist's performance as an educator through the practice of "Didactic Transposition". For the development of this article, a bibliographic search was carried out in Lilacs, SciELO, Medline, Google Academic and Capes Thesis and Dissertation Catalogues. This material can be used as a basis for the nutrition professional to make a comparative analysis of the vegetables’ nutritional composition with other conventional foods consumed by the general population. Thus, the educator will have information that will contribute to the "knowledge to teach" and the possible expansion of the students’ "learned knowledge", thus seeking a change in food behavior in favor of health. Keywords: Alternative Foods. Food Plants. Didatic Transposition.

Extracellular Matrix Biomarkers in Colorectal Cancer

The cellular microenvironment composition and changes therein play an extremely important role in cancer development. Changes in the extracellular matrix (ECM), which constitutes a majority of the tumor stroma, significantly contribute to the development of the tumor microenvironment. These alterations within the ECM and formation of the tumor microenvironment ultimately lead to tumor development, invasion, and metastasis. The ECM is composed of various molecules such as collagen, elastin, laminin, fibronectin, and the MMPs that cleave these protein fibers and play a central role in tissue remodeling. When healthy cells undergo an insult like DNA damage and become cancerous, if the ECM does not support these neoplastic cells, further development, invasion, and metastasis fail to occur. Therefore, ECM-related cancer research is indispensable, and ECM components can be useful biomarkers as well as therapeutic targets. Colorectal cancer specifically, is also affected by the ECM and many studies have been conducted to unravel the complex association between the two. Here we summarize the importance of several ECM components in colorectal cancer as well as their potential roles as biomarkers.

Natural Dyeing of Cellulose and Protein Fibers with the Flower Extract of Spartium junceum L. Plant

In this study, the natural dye was extracted from Spartium junceum L. (SJL) flowers and applied on cellulose (cotton) and protein (wool) fabric. Fabrics were pre-mordant with alum prior to the dyeing process. Considering the global requirements on zero waste and green policy, the dyeing process was intended to be as much as possible environmentally friendly but still effective. Therefore, mordant concentration was optimized due to the reduction of the negative impact. The efficiency of the dyeing process was investigated by examination of fabrics’ color characteristics and colorfastness to washing properties. In this paper, we have proved that the extracted dye from Spartium junceum L. is an acidic dye (mordant dye) which is more applicable for the treatment of wool fabrics. In this paper, it was proved that phytochemicals responsible for coloring are part of the flavonoids group. The UV absorption spectra of extracted dye show 4 bands in the region of λmax 224, 268, 308 and 346 nm which are ascribed to bands characteristic for flavonoids. Wool fabric pre-mordant with 3% alum and dyed shows great chromatic (C*) properties where C* value is in a range from 47.76 for unwashed samples to 47.50 for samples after 5 washing cycles and color hue (h°) is in a range 82.13 for unwashed samples to 81.52 for samples after 5 washing cycles. The best result regarding the colorfastness properties is shown by the wool sample treated with 3% alum after 5 washing cycles (total difference in color (Delta E*) = 0.87). These results confirm that metal (Al) from alum mordant make strong chemical bonds with wool substrate and dye since Delta E* values decrease in comparison to Delta E* values of the cotton samples treated the same way. The results revealed it is possible to reduce the concentration of mordant up to 3% and obtain satisfactory results regarding the colorfastness. Nevertheless, future research will go in the direction of replacing synthetic mordant with a more environmentally friendly one.

Bioactive hierarchical silk fibers created by bioinspired self-assembly

Artificial recapitulation of the hierarchy of natural protein fibers is crucial to providing strategies for developing advanced fibrous materials. However, it is challenging due to the complexity of the natural environment. Inspired by the liquid crystalline spinning of spiders, we report the development of natural silk-like hierarchical fibers, with bundles of nanofibrils aligned in their long-axis direction, by self-assembly of crystallized silk fibroin (SF) droplets. The formation of self-assembled SF fibers is a process of coalesced droplets sprouting to form a branched fibrous network, which is similar to the development of capillaries in our body. The as-assembled hierarchical SF fibers are highly bioactive and can significantly enhance the spreading and growth of human umbilical vein endothelial cells compared to the natural SF fibers. This work could help to understand the natural silk spinning process of spiders and provides a strategy for design and development of advanced fibrous biomaterials for various applications.

Silkworm spinning: the programmed self-assembly from natural silk fibroin to superfibre

Silkworm silk is one of the best natural protein fibers spun by the silkworm at ambient temperature and pressure using aqueous silk protein solution. It is a great challenge to reproduce high-performance artificial fibers comparable to natural silk by bionics for the incomplete understanding of silkworm spinning mechanism, especially the structure and assembly of natural silk fibroin (NSF) in the silk gland. Here, we studied the structure and assembly of NSF with the assistance of amphipol and digitonin. Our results showed NSFs were present as nanofibrils primarily composed of random coils in the silk gland. Metal ions were vital for the formation of NSF nanofibrils. The successive decrease in pH from posterior silk gland (PSG) to anterior silk gland (ASG) resulted in a gradual increase in NSF hydrophobicity. NSF nanofibrils were randomly arranged from PSG to ASG-1, and then self-assembled into herringbone-like patterns near the spinneret (ASG-2) ready for silkworm spinning. Our study reveals the mechanism by which silkworms cleverly utilize metal ions and pH gradient in the silk gland to drive the programmed self-assembly of NSF from disordered nanofibrils to anisotropic liquid crystalline spinning dope (herringbone-like patterns) for silkworm spinning, thus providing novel insights into silkworm/spider spinning mechanism and bionic creation of high-performance fibers.