The Dependence of Mechanical Properties of Adult Rat Myocytes on Cell Alignment

2008 ◽  
Author(s):  
Honghai Liu ◽  
Julie X. Yun ◽  
Russel K. Pirlo ◽  
Delpine Dean ◽  
Hai Yao ◽  
...  
Keyword(s):  
Cardiac Tissue ◽  
The Body ◽  
Cell Alignment ◽  
Culture Dish ◽  
Adult Rat ◽  
Laser Alignment ◽  
Adult Cardiomyocytes ◽  
Cell Micropatterning ◽  
A Cell ◽  
Controlled Environments

In response to damage, stress and cell death cardiac muscle undergoes remodeling in which cardiomyocytes de-differentiate and re-differentiate. An understanding of the mechanisms involved in this process may lead to therapies to promote and enhance the repair of damaged cardiac tissue. However, due to the complexity of native environments, it is hard to investigate this remodeling process directly on tissues isolated from the body. Therefore, it is important to construct a cell-culture model that will replicate the most relevant characteristics of that tissue in controlled environments with greater capability to be assessed. Native cardiac myocytes have an aligned arrangement in which neighboring cardiomyocytes are electrically and mechanical coupled through contact junctions. When adult cardiomyocytes are placed into a culture dish, the cells will be randomly oriented and lose their native phenotypes gradually due to the lack of proper aligned cell-cell connections. To address this issue, we have implemented our laser cell micropatterning system to create an adult cardiomyocyte culturing model with aligned rows of cells connected end to end. In this abstract, we describe the experimental procedure to achieve the laser alignment of adult cardiomyocytes and the results of mechanical property testing of the myocytes investigated using Multimode Picoforce Nanoscope Atomic Force Microscope (AFM) (Veeco).

scholarly journals Power Failure of Mitochondria and Oxidative Stress in Neurodegeneration and Its Computational Models

Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 229
Author(s):  
JunHyuk Woo ◽  
Hyesun Cho ◽  
YunHee Seol ◽  
Soon Ho Kim ◽  
Chanhyeok Park ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Mitochondrial Dysfunction ◽  
Computational Models ◽  
Neuronal Damage ◽  
Living Organism ◽  
The Body ◽  
Mitochondrial Functions ◽  
A Cell ◽  
The Brain ◽  
And Oxidative Stress

The brain needs more energy than other organs in the body. Mitochondria are the generator of vital power in the living organism. Not only do mitochondria sense signals from the outside of a cell, but they also orchestrate the cascade of subcellular events by supplying adenosine-5′-triphosphate (ATP), the biochemical energy. It is known that impaired mitochondrial function and oxidative stress contribute or lead to neuronal damage and degeneration of the brain. This mini-review focuses on addressing how mitochondrial dysfunction and oxidative stress are associated with the pathogenesis of neurodegenerative disorders including Alzheimer’s disease, amyotrophic lateral sclerosis, Huntington’s disease, and Parkinson’s disease. In addition, we discuss state-of-the-art computational models of mitochondrial functions in relation to oxidative stress and neurodegeneration. Together, a better understanding of brain disease-specific mitochondrial dysfunction and oxidative stress can pave the way to developing antioxidant therapeutic strategies to ameliorate neuronal activity and prevent neurodegeneration.

Abstract 14201: The Application of Hipsc-derived Cardiomyocytes Paced by Re-entrant Waves for Drug Assessment

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Junjun Li ◽  
Itsunari Minami ◽  
Shigeru Miyagawa ◽  
Xiang Qu ◽  
YING HUA ◽  
...  
Keyword(s):  
Cardiac Tissue ◽  
Troponin T ◽  
Field Potential ◽  
Electrical Signal ◽  
Assessment System ◽  
K Channel ◽  
Control Group ◽  
Culture Dish ◽  
Robust Response

Introduction: How to precisely evaluate response in newly developed medications in vitro may be a great concern in drug screening. We modified normal low-attachment culture dish and created closed-loop tissue ring from single hiPSC-CMs. We hypothesized that the re-entrant wave (ReW) could originate and pace the cardiac tissue ring, and the CMs under pacing could be matured and used for drug assessment. Methods: PDMS wells and pillars were mounted in low-attachment petri dishes (Figure 1A). 4 х 10 5 hiPSC-CMs were plated into the wells to form tissue ring where the ReW could spontaneously originate. After cultivation for 14 days, the hiPSC-CMs were evaluated by immunostaining and gene expression. Micro electrode array (MEA) were used to evaluating the CM response to different drugs. Results: The electrical signal recorded by MEA indicated that the ReWs could make the CMs beat at a much higher rate than the Control group (Figure 1B, 123.26 ± 10.36 bpm vs. 14.08 ± 4.53 bpm, p<0.0001). After 14 day culture, the ReW group demonstrated significantly higher expression of Troponin T (TnT2), myosin heavy chain 7 (β-MHC), and α-actinin. Interestingly, the α-actinin staining indicated alignment of CMs within the ReW group (Figure 1C). The CMs under ReW pacing showed robust response to several cardiac compounds including E4031, (hERG K+ channel blocker, Figure 1D and E), isoproterenol (β adrenoceptor agonist) and propranolol (beta-blocker). Both the field potential as well as the Ca 2+ transients showed correlated dose-dependent change and the recovering after washout of the drugs. Conclusions: The ReWs could spontaneously originate in the cultured cardiac tissue ring with enhancement of the maturation in the hiPSC-CMs and robust response to various drugs, indicating the system as a robust drug assessment system with multiple read-out methods.

scholarly journals Ca2+-ATPase activity and Ca2+ uptake by sarcoplasmic reticulum in fish heart: effects of thermal acclimation.

1998 ◽  
Vol 201 (4) ◽  
pp. 525-532 ◽  
Author(s):  
E Aho ◽  
M Vornanen
Keyword(s):  
Atpase Activity ◽  
Uptake Rate ◽  
Teleost Fish ◽  
Crucian Carp ◽  
Thermal Acclimation ◽  
The Body ◽  
Newborn Rat ◽  
Fish Heart ◽  
Adult Rat ◽  
Uptake Velocity

This study was designed to compare the activities of sarcoplasmic (SR) Ca2+-ATPase and Ca2+ uptake in fish and mammalian hearts and to determine whether thermal acclimation has any effect on the function of the cardiac SR in fish. To this end, we measured thapsigargin-sensitive Ca2+-ATPase activity and thapsigargin-inhibitable Ca2+ uptake velocity in crude cardiac homogenates of newborn and adult rats and of two teleost fish (crucian carp and rainbow trout) acclimated to low (4 degrees C) and high (17 degrees C and 24 degrees C for trout and carp, respectively) ambient temperatures. The TG-sensitive Ca2+-ATPase activity was highest in adult rat, and the corresponding activities of cold-acclimated trout, warm-acclimated trout, warm-acclimated carp, cold-acclimated carp and newborn rat were 76, 58, 43, 28 and 23 %, respectively, of that of the adult rat at 25 degrees C. SR Ca2+ uptake velocity, measured using Fura-2 at room temperature (approximately 22 degrees C), was highest in cold-acclimated trout, and the values for adult rat, warm-acclimated trout, newborn rat, warm-acclimated carp and cold-acclimated carp were 93, 56, 24, 21 and 14 % of the uptake velocity of cold-acclimated trout, respectively. When corrected to the body temperature of the animal, the relative rates of SR Ca2+ uptake were 100, 26, 19, 18, 11 and 2 % for adult rat, newborn rat, cold-acclimated trout, warm-acclimated trout, warm-acclimated carp and cold-acclimated carp, respectively. These findings show that SR Ca2+ uptake is slower in fish than in mammalian hearts and that marked species-specific differences exist among teleost fish in this respect. Furthermore, acclimation to cold increases the Ca2+ uptake rate of trout cardiac SR (complete thermal compensation) but decreases the SR Ca2+ uptake rate of crucian carp heart. This difference in acclimation response probably reflects the different activity patterns of the two species in their natural habitat during the cold season.

scholarly journals Особливості масометричних показників та морфологічних змін головного мозку статевозрілих щурів в умовах впливу на організм сульфатів міді, цинку та заліза

2015 ◽  
Author(s):  
А. М. Романюк ◽  
Г. Ю Будко
Keyword(s):  
Copper Sulfate ◽  
Morphological Changes ◽  
The Body ◽  
Male Rats ◽  
Relative Mass ◽  
Adult Rat ◽  
Applied Anatomy ◽  
Adult Rat Brain ◽  
Long Acting ◽  
The Brain

ОСОБЛИВОСТІ МАСОМЕТРИЧНИХ ПОКАЗНИКІВ ТА МОРФОЛОГІЧНИХ ЗМІН ГОЛОВНОГО МОЗКУ СТАТЕВОЗРІЛИХ ЩУРІВ В УМОВАХ ВПЛИВУ НА ОРГАНІЗМ СУЛЬФАТІВ МІДІ, ЦИНКУ ТА ЗАЛІЗА - З метою вивчення масометричних показників щурів та їх головного мозку за умов довготривалої дії (упродовж 90 діб) на організм сульфатів міді, цинку та заліза було проведено експеримент на 48 білих статевозрілих щурах-самцях масою 200-250 г віком 5-7 місяців. Застосовували анатомічні, статистичні та загальноприйняті методики мікроанатомічного методу дослідження. Встановлено, що комбінований вплив на організм сульфатів міді цинку та заліза чинить на головний мозок досить виражений токсичний ефект, що негативно позначається на масометричних показниках загальної маси щурів та маси головного мозку. Це свідчить про розвиток у головному мозку явищ гострого набряку з ознаками геморагічної інфільтрації. Ступінь вираження набряку зростає та досягає максимальних показників наприкінці експерименту.<br />ОСОБЕННОСТИ МАСОМЕТРИЧЕСКИХ ПОКАЗАТЕЛЕЙ И МОРФОЛОГИЧЕСКИХ ИЗМЕНЕНИЙ ГОЛОВНОГО МОЗГА ПОЛОВОЗРЕЛЫХ КРЫС В УСЛОВИЯХ ВОЗДЕЙСТВИЯ НА ОРГАНИЗМ СУЛЬФАТОВ МЕДИ, ЦИНКА И ЖЕЛЕЗА - С целью изучения масометрических показателей крыс и их головного мозга в условиях длительного действия (в течение 90 суток) на организм сульфатов меди, цинка и железа был проведен эксперимент на 48 белых половозрелых крысах-самцах массой 200250 г в возрасте 5-7 месяцев. Применялись анатомические, статистические и общепринятые методики микроанатомического метода исследования. Установлено, что комбинированное воздействие на организм сульфатов меди и цинка и железа оказывает на мозг достаточно выразительный токсический эффект, что отрицательно сказывается на массометрических показателях общего веса крыс и веса головного мозга. Это свидетельствует о развитии в головном мозге явлений острого отека с признаками геморрагической инфильтрации, степень выраженности которого максимальна в конце эксперимента.<br />FEATURES OF MASS INDICES AND MORPHOLOGICAL CHANGES IN ADULT RAT BRAIN UNDER THE INFLUENCE ON THE BODY OF COPPER SULFATE, ZINC AND IRON - To study the performance of rats and their mass brain in long acting (for 90 days) on the body of copper sulfate, zinc and iron, an experiment was conducted on 48 white adult male rats weighing 200-250 gram, aged 5-7 months. There was applied anatomy, statistics and conventional techniques microanatomical research method. It was established that the combined effect on the body of copper and zinc sulphates and iron in the brain has enough expressive toxicity, which affects performance on the total weight of the rats and brain weight. This testifies to the development of brain edema, acute phenomena with signs of hemorrhagic infiltration. The severity of edema increases and reaches maximum performance at the end of the experiment.<br />Ключові слова: головний мозок, солі важких металів, відносна маса, коефіцієнт цефалізації.<br />Ключевые слова: головной мозг, соли тяжелых металлов, относительная масса, коэффициент цефа- лизации.<br />Key words: brain, salts of heavy metals, relative mass, ratio cephalization.

scholarly journals Identification of Freshness of Marine Fish Based on Image of Hue Saturation Value and Morphology

Jurnal INFORM ◽  
2021 ◽  
Vol 6 (1) ◽  
pp. 40-48
Author(s):  
Ekojono Ekojono ◽  
Al Wegi Herman ◽  
Mentari Mustika
Keyword(s):  
Nearest Neighbor ◽  
The Body ◽  
K Nearest Neighbor ◽  
The People ◽  
Image Conversion ◽  
Object Part ◽  
A Cell ◽  
Protein Amino Acids ◽  
Image Object ◽  
Rgb Image

Euthynus is one of the fish that is widely consumed for the enjoyment of the people of Indonesia or abroad, because of its very soft quality, easy to obtain, and contains a lot of essential protein amino acids that are good for the body. This research aims to identify the freshness of the fish purchased based on the eyes and fish gills. The initial process of identifying the freshness of fish uses several methods. Image input process through image object taking using a cell phone camera. The image object is used to determine the value of the RGB image object. RGB color extraction clarifies the value obtained from the image object before proceeding to the next process. Image resize is the process of cutting the image on the desired object part. Image conversion using the HSV method was used to determine the freshness of fish in the gills. The Local Binary Pattern method is used to determine the freshness of the fisheye. The next step is to refine the RGB image into Morphology. The KNN (K-Nearest Neighbor Method) method is used to group objects based on learning data closest to the object. The journal analysis results on the comparison of methods, after 45 trials for each method, found that the Hue Saturation Value method obtained the highest success by 90% and for the texture value obtained 85% success.

A Mechanistic Motor-Clutch Model That Explains Cell Shape Dynamics to Cyclic Stretch

2022 ◽  
Author(s):  
Benjamin W. Scandling ◽  
Jia Gou ◽  
Jessica Thomas ◽  
Jacqueline Xuan ◽  
Chuan Xue ◽  
...  
Keyword(s):  
Computational Model ◽  
Computational Models ◽  
The Body ◽  
Cyclic Stretch ◽  
Substrate Stiffness ◽  
Cell Alignment ◽  
Cellular Mechanisms ◽  
Actin Bundles ◽  
The Impact

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.

The distribution of E-cadherin during Xenopus laevis development

Development ◽  
1991 ◽  
Vol 111 (1) ◽  
pp. 159-169 ◽  
Author(s):  
G. Levi ◽  
B. Gumbiner ◽  
J.P. Thiery
Keyword(s):  
Xenopus Laevis ◽  
Developmental Stages ◽  
Early Embryo ◽  
The Body ◽  
Gut Epithelium ◽  
A Cell ◽  
Well Differentiated ◽  
Sensory Layer ◽  
Endodermal Cells ◽  
E Cadherin

A vast amount of experimental evidence suggests that cell surface molecules involved in cell-to-cell and/or cell-to-substrate interactions participate in the control of basic events in morphogenesis. E-cadherin is a cell adhesion molecule directly implicated in the control of Ca2(+)-dependent interactions between epithelial cells. We report here the patterns of expression of E-cadherin in developmental stages of Xenopus laevis ranging from early embryo to adult using immunofluorescence microscopy. Although its distribution shares some similarities with those of L-CAM in the chicken and E-cadherin/Uvomorulin in the mouse, the distribution of E-cadherin in Xenopus presents several peculiar and unique features. In early stages of Xenopus development, E-cadherin is not expressed. The molecule is first detectable in the ectoderm of late gastrulas (stage 13-13.5 NF). At this time both the external and the sensory layer of the nonneural ectoderm accumulate high levels of E-cadherin while the ectoderm overlying the neural plate and regions of the involuting marginal zone (IMZ) not yet internalized by the movements of gastrulation are E-cadherin-negative. Unlike most other species, endodermal cells express no or very low levels of E-cadherin up to stage 20 NF. Endodermal cells become strongly E-cadherin-positive only when a well-differentiated epithelium forms in the gut. No mesodermal structures are stained during early development. In the placodes, in contrast to other species, E-cadherin disappears very rapidly after placode thickening. During further embryonic development E-cadherin is present in the skin, the gut epithelium, the pancreas, many monostratified epithelia and most glands. Hepatocytes are stained weakly while most other tissues, including the pronephros, are negative. In the mesonephros, the Wolffian duct and some tubules are positive. During metamorphosis a profound restructuring of the body plan takes place under the control of thyroid hormones, which involves the degeneration and subsequent regeneration of several tissues such as the skin and the gut. All newly formed epithelia express high levels of E-cadherin. Surprisingly, degenerating epithelia of both skin and intestine maintain high levels of the protein even after starting to become disorganized and to degenerate. In the adult, staining is strong in the skin, the glands, the lungs, the gut epithelium and the pancreas, weak in the liver and absent from most other tissues. Our results show that the expression of E-cadherin in Xenopus is strongly correlated with the appearance of differentiated epithelia.

Extracellular vesicles, stem cells and the role of miRNAs in neurodegeneration

2021 ◽  
Vol 19 ◽  
Author(s):  
Ayaz M. Belkozhayev ◽  
Minnatallah Al-Yozbaki ◽  
Alex George ◽  
Raigul Ye Niyazova ◽  
Kamalidin O. Sharipov ◽  
...  
Keyword(s):  
Stem Cells ◽  
Neurodegenerative Diseases ◽  
Extracellular Vesicles ◽  
Intercellular Communication ◽  
Direct Consequence ◽  
Therapeutic Benefit ◽  
The Body ◽  
A Cell ◽  
Crucial Information

There are different modalities of intercellular communication governed by cellular homeostasis. In this review, we will explore one of these forms of communication called extracellular vesicles (EVs). These vesicles are released by all cells in the body and are heterogeneous in nature. The primary function of EVs is to share information through their cargo consisting of proteins, lipids and nucleic acids (mRNA, miRNA, dsDNA etc.) with other cells, which have a direct consequence on their microenvironment. We will focus on the role of EVs of mesenchymal stem cells (MSCs) in the nervous system and how these participate in intercellular communication to maintain physiological function and provide neuroprotection. However, deregulation of this same communication system could play a role in several neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, Amyotrophic lateral sclerosis, multiple sclerosis, prion disease and Huntington’s disease. The release of EVs from a cell provides crucial information to what is happening inside the cell and thus could be used in diagnostics and therapy. We will discuss and explore new avenues for the clinical applications of using engineered MSC-EVs and their potential therapeutic benefit in treating neurodegenerative diseases.

Data Mining with Cubegrades

2011 ◽  
pp. 519-525
Author(s):  
Amin A. Abdulghani
Keyword(s):  
Association Rules ◽  
Association Rule ◽  
The Body ◽  
General View ◽  
Arbitrary Measure ◽  
Support Count ◽  
A Cell ◽  
Delta Change ◽  
Probabilistic Rule ◽  
And Function

A lot of interest has been expressed in database mining using association rules (Agrawal, Imielinski, & Swami, 1993). In this chapter, we provide a different view of the association rules, referred to as cubegrades (Imielinski, Khachiyan, & Abdulghani, 2002) . An example of a typical association rule states that, say, 23% of supermarket transactions (so called market basket data) which buy bread and butter buy also cereal (that percentage is called confidence) and that 10% of all transactions buy bread and butter (this is called support). Bread and butter represent the body of the rule and cereal constitutes the consequent of the rule. This statement is typically represented as a probabilistic rule. But association rules can also be viewed as statements about how the cell representing the body of the rule is affected by specializing it by adding an extra constraint expressed by the rule’s consequent. Indeed, the confidence of an association rule can be viewed as the ratio of the support drop, when the cell corresponding to the body of a rule (in our case the cell of transactions buying bread and butter) is augmented with its consequent (in this case cereal). This interpretation gives association rules a “dynamic flavor” reflected in a hypothetical change of support affected by specializing the body cell to a cell whose description is a union of body and consequent descriptors. For example, our earlier association rule can be interpreted as saying that the count of transactions buying bread and butter drops to 23% of the original when restricted (rolled down) to the transactions buying bread, butter and cereal. In other words, this rule states how the count of transactions supporting buyers of bread and butter is affected by buying cereal as well. With such interpretation in mind, a much more general view of association rules can be taken, when support (count) can be replaced by an arbitrary measure or aggregate and the specialization operation can be substituted with a different “delta” operation. Cubegrades capture this generalization. Conceptually, this is very similar to the notion of gradients used in calculus. By definition the gradient of a function between the domain points x1 and x2 measures the ratio of the delta change in the function value over the delta change between the points. For a given point x and function f(), it can be interpreted as a statement of how a change in the value of x (?x), affects a change of value in the function (? f(x)).

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