cell alignment
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2022 ◽  
Vol 3 (2) ◽  
pp. 269-278
Author(s):  
Rika Harman ◽  
Tukino Tukino ◽  
Amrizal Amrizal ◽  
Sasa Ani Arnomo

The material provided in this training is divided into 3 groups, namely Microsoft Word 2010, Microsoft PowerPoint 2013, and Microsoft Paint groups. The briefing material given to the Microsoft PowerPoint 2010 group was the introduction of spreadsheets, starting from worksheets, to the use of functions and formulas to solve problems. Activities are carried out based on the division of the ability/skill level of each teacher. Teachers who have been proficient are grouped separately from teachers who are still new to computers so that coaching is more intensive. Teachers who are still laymen are guided and accompanied by instructors starting from the procedure for turning on the computer, opening files, saving files, using the mouse, basic typing, introduction to computer parts to the procedure for turning off the computer. The introduction to the spread sheet material begins with explaining worksheets, menu functions, and how to create borders, introducing cell alignment, and introducing Microsoft Excel formulas and functions to solve a particular problem/case. So far we have known more or less about Microsoft Office, including Microsoft Office XP, Microsoft Office 2003, Microsoft Office 2007, and the latest we know is Microsoft Office 2010.


Author(s):  
Benjamin W. Scandling ◽  
Jia Gou ◽  
Jessica Thomas ◽  
Jacqueline Xuan ◽  
Chuan Xue ◽  
...  

Many cells in the body experience cyclic mechanical loading, which can impact cellular processes and morphology. In vitro studies often report that cells reorient in response to cyclic stretch of their substrate. To explore cellular mechanisms involved in this reorientation, a computational model was developed by utilizing the previous computational models of the actin-myosin-integrin motor-clutch system developed by others. The computational model predicts that under most conditions, actin bundles align perpendicular to the direction of applied cyclic stretch, but under specific conditions, such as low substrate stiffness, actin bundles align parallel to the direction of stretch. The model also predicts that stretch frequency impacts the rate of reorientation, and that proper myosin function is critical in the reorientation response. These computational predictions are consistent with reports from the literature and new experimental results presented here. The model suggests that the impact of different stretching conditions (stretch type, amplitude, frequency, substrate stiffness, etc.) on the direction of cell alignment can largely be understood by considering their impact on cell-substrate detachment events, specifically whether detachment occurs during stretching or relaxing of the substrate.


2022 ◽  
Author(s):  
Junjie Xiong ◽  
Han Wang ◽  
Xingzi Lan ◽  
Yaqi Wang ◽  
Zixu Wang ◽  
...  

Abstract Many strategies have been adopted to engineer bone-ligament interface, which is of great value to both the tissue regeneration and the mechanism understanding underlying interface regeneration. However, how to recapitulate the complexity and heterogeneity of the native bone-ligament interface including the structural, cellular and mechanical gradients is still challenging. In this work, a bioinspired grid-crimp micropattern fabricated by melt electrospinning writing (MEW) was proposed to mimic the native structure of bone-ligament interface. The printing strategy of crimped fiber micropattern was developed and the processing parameters were optimized, which were used to mimic the crimp structure of the collagen fibrils in ligament. The guidance effect of the crimp angle and fiber spacing on the orientation of fibroblasts was studied, and both of them showed different levels of cell alignment effect.. MEW grid micropatterns with different fiber spacings were fabricated as bone region. Both the alkaling phosphatase activity and calcium mineralization results demonstrated the higher osteoinductive ability of the MEW grid structures, especially for that with smaller fiber spacing. The combined grid-crimp micropatterns were applied for the co-culture of fibroblasts and osteoblasts. The results showed that more cells were observed to migrate into the in-between interface region for the pattern with smaller fiber spacing, suggested the faster migration speed of cells. Finally, a cylindrical triphasic scaffold was successfully generated by rolling the grid-crimp micropatterns up, showing both structural and mechanical similarity to the native bone-ligament interface. In summary, the proposed strategy is reliable to fabricate grid-crimp triphasic micropatterns with controllable structural parameters to mimic the native bone-to-ligament structure, and the generated 3D scaffold shows great potential for the further bone-ligament interface tissue engineering.


Author(s):  
Koichi Matsuo ◽  
Ryota Tamura ◽  
Kohji Hotta ◽  
Mayu Okada ◽  
Akihisa Takeuchi ◽  
...  

The locomotor system is highly bilateral at the macroscopic level. Homochirality of biological molecules is fully compatible with the bilateral body. However, whether and how single-handed cells contribute to the bilateral locomotor system is obscure. Here, exploiting the small number of cells in the swimming tadpole larva of the ascidian Ciona, we analyzed morphology of the tail at cellular and subcellular scales. Quantitative phase-contrast X-ray tomographic microscopy revealed a high-density midline structure ventral to the notochord in the tail. Muscle cell nuclei on each side of the notochord were roughly bilaterally aligned. However, fluorescence microscopy detected left-right asymmetry of myofibril inclination relative to the longitudinal axis of the tail. Zernike phase-contrast X-ray tomographic microscopy revealed the presence of left-handed helices of myofibrils in muscle cells on both sides. Therefore, the locomotor system of ascidian larvae harbors symmetry-breaking left-handed helical cells, while maintaining bilaterally symmetrical cell alignment. These results suggest that bilateral animals can override cellular homochirality to generate the bilateral locomotor systems at the supracellular scale.


2021 ◽  
Author(s):  
Pinar Demetci ◽  
Rebecca Santorella ◽  
Bjorn Sandstede ◽  
Ritambhara Singh

Integrated analysis of multi-omics data allows the study of how different molecular views in the genome interact to regulate cellular processes; however, with a few exceptions, applying multiple sequencing assays on the same single cell is not possible. While recent unsupervised algorithms align single-cell multi-omic datasets, these methods have been primarily benchmarked on co-assay experiments rather than the more common single-cell experiments taken from separately sampled cell populations. Therefore, most existing methods perform subpar alignments on such datasets. Here, we improve our previous work Single Cell alignment using Optimal Transport (SCOT) by using unbalanced optimal transport to handle disproportionate cell-type representation and differing sample sizes across single-cell measurements. We show that our proposed method, SCOTv2, consistently yields quality alignments on five real-world single-cell datasets with varying cell-type proportions and is computationally tractable. Additionally, we extend SCOTv2 to integrate multiple ($M\geq2$) single-cell measurements and present a self-tuning heuristic process to select hyperparameters in the absence of any orthogonal correspondence information.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Wenzheng He ◽  
Xiongying Ye ◽  
Tianhong Cui

AbstractTraditional lithography plays a significant role in the fabrication of micro- and nanostructures. Nevertheless, the fabrication process still suffers from the limitations of manufacturing devices with a high aspect ratio or three-dimensional structure. Recent findings have revealed that shrink polymers attain a certain potential in micro- and nanostructure manufacturing. This technique, denoted as heat-induced shrink lithography, exhibits inherent merits, including an improved fabrication resolution by shrinking, controllable shrinkage behavior, and surface wrinkles, and an efficient fabrication process. These merits unfold new avenues, compensating for the shortcomings of traditional technologies. Manufacturing using shrink polymers is investigated in regard to its mechanism and applications. This review classifies typical applications of shrink polymers in micro- and nanostructures into the size-contraction feature and surface wrinkles. Additionally, corresponding shrinkage mechanisms and models for shrinkage, and wrinkle parameter control are examined. Regarding the size-contraction feature, this paper summarizes the progress on high-aspect-ratio devices, microchannels, self-folding structures, optical antenna arrays, and nanowires. Regarding surface wrinkles, this paper evaluates the development of wearable sensors, electrochemical sensors, energy-conversion technology, cell-alignment structures, and antibacterial surfaces. Finally, the limitations and prospects of shrink lithography are analyzed.


2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi202-vi202
Author(s):  
Sangjo Kang ◽  
Anirudh Sattiraju ◽  
Yuhuan Li ◽  
Shalaka Wahane ◽  
Theo Hanna ◽  
...  

Abstract Glioblastoma (GBM) is the most common malignant primary brain tumor. The nature of invasiveness of GBM makes complete surgical resection difficult. However, how GBM cells achieve wide infiltration in the brain is poorly understood. Microglia, the resident immune cells in the brain can support GBM growth and invasion, but the underlying mechanisms remain elusive. Here, we show that microglia are activated in a wide field away from tumor boundaries, ahead of tumor cell infiltration. Invading GBM cells are in close contact with microglia, progressively aligned with one another in the direction of tumor invasion. Moreover, ECM is also aligned with the infiltrating tumor and microglia, which may serve as invasion tracks in the brain. Mechanistically, we demonstrate that microglia direct cellular alignment and ECM remodeling in the invasion tracks through an axon guidance receptor Plexin-B2. Myeloid-specific ablation of Plexin-B2 perturbs microglia and tumor cell alignment, microglia migration, ECM organization, and GBM invasiveness. Together, our data reveal a hitherto under-appreciated role of microglia in providing directional cues for GBM invasion through physical interaction and alignment of ECM and tumor cells, thus providing new insights and novel molecular targets in curbing GBM invasion.


2021 ◽  
Vol 17 (11) ◽  
pp. e1009063
Author(s):  
Tania Mendonca ◽  
Ana A. Jones ◽  
Jose M. Pozo ◽  
Sarah Baxendale ◽  
Tanya T. Whitfield ◽  
...  

A common feature of morphogenesis is the formation of three-dimensional structures from the folding of two-dimensional epithelial sheets, aided by cell shape changes at the cellular-level. Changes in cell shape must be studied in the context of cell-polarised biomechanical processes within the epithelial sheet. In epithelia with highly curved surfaces, finding single-cell alignment along a biological axis can be difficult to automate in silico. We present ‘Origami’, a MATLAB-based image analysis pipeline to compute direction-variant cell shape features along the epithelial apico-basal axis. Our automated method accurately computed direction vectors denoting the apico-basal axis in regions with opposing curvature in synthetic epithelia and fluorescence images of zebrafish embryos. As proof of concept, we identified different cell shape signatures in the developing zebrafish inner ear, where the epithelium deforms in opposite orientations to form different structures. Origami is designed to be user-friendly and is generally applicable to fluorescence images of curved epithelia.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Miguel F. Tenreiro ◽  
Henrique V. Almeida ◽  
Tomás Calmeiro ◽  
Elvira Fortunato ◽  
Lino Ferreira ◽  
...  

AbstractThe extracellular matrix (ECM) of engineered human cardiac tissues corresponds to simplistic biomaterials that allow tissue assembly, or animal derived off-the-shelf non-cardiac specific matrices. Decellularized ECM from human cardiac tissue could provide a means to improve the mimicry of engineered human cardiac tissues. Decellularization of cardiac tissue samples using immersion-based methods can produce acceptable cardiac ECM scaffolds; however, these protocols are mostly described for animal tissue preparations. We have tested four methods to decellularize human cardiac tissue and evaluated their efficiency in terms of cell removal and preservation of key ECM components, such as collagens and sulfated glycosaminoglycans. Extended exposure to decellularization agents, namely sodium dodecyl sulfate and Triton-X-100, was needed to significantly remove DNA content by approximately 93% in all human donors. However, the biochemical composition of decellularized tissue is affected, and the preservation of ECM architecture is donor dependent. Our results indicate that standardization of decellularization protocols for human tissue is likely unfeasible, and a compromise between cell removal and ECM preservation must be established in accordance with the scaffold’s intended application. Notwithstanding, decellularized human cardiac ECM supported human induced pluripotent-derived cardiomyocyte (hiPSC-CM) attachment and retention for up to 2 weeks of culture, and promoted cell alignment and contraction, providing evidence it could be a valuable tool for cardiac tissue engineering.


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