scholarly journals Optimization of Complete Rat Heart Decellularization Using Artificial Neural Networks

Micromachines ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 79
Author(s):  
Greta Ionela Barbulescu ◽  
Taddeus Paul Buica ◽  
Iacob Daniel Goje ◽  
Florina Maria Bojin ◽  
Valentin Laurentiu Ordodi ◽  
...  
Keyword(s):  
Neural Networks ◽  
Histological Analysis ◽  
Sodium Dodecyl ◽  
Sprague Dawley ◽  
Deep Convolutional Neural Networks ◽  
Software Application ◽  
Sprague Dawley Rats ◽  
Machine Learning Approach ◽  
Image Set ◽  
Exact Moment

Whole organ decellularization techniques have facilitated the fabrication of extracellular matrices (ECMs) for engineering new organs. Unfortunately, there is no objective gold standard evaluation of the scaffold without applying a destructive method such as histological analysis or DNA removal quantification of the dry tissue. Our proposal is a software application using deep convolutional neural networks (DCNN) to distinguish between different stages of decellularization, determining the exact moment of completion. Hearts from male Sprague Dawley rats (n = 10) were decellularized using 1% sodium dodecyl sulfate (SDS) in a modified Langendorff device in the presence of an alternating rectangular electric field. Spectrophotometric measurements of deoxyribonucleic acid (DNA) and total proteins concentration from the decellularization solution were taken every 30 min. A monitoring system supervised the sessions, collecting a large number of photos saved in corresponding folders. This system aimed to prove a strong correlation between the data gathered by spectrophotometry and the state of the heart that could be visualized with an OpenCV-based spectrometer. A decellularization completion metric was built using a DCNN based classifier model trained using an image set comprising thousands of photos. Optimizing the decellularization process using a machine learning approach launches exponential progress in tissue bioengineering research.

Characterization of vasoactive intestinal peptide receptors on rat alveolar macrophages

1994 ◽  
Vol 267 (3) ◽  
pp. L256-L262 ◽  
Author(s):  
H. Sakakibara ◽  
K. Shima ◽  
S. I. Said
Keyword(s):  
Vasoactive Intestinal Peptide ◽  
Alveolar Macrophages ◽  
Inflammatory Responses ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
High Capacity ◽  
Sprague Dawley ◽  
Major Band ◽  
High Affinity ◽  
Sprague Dawley Rats

In view of the evidence that vasoactive intestinal peptide (VIP) may modulate acute inflammatory injury in the lung, we investigated the presence and characteristics of VIP receptors on alveolar macrophages (AMs). We examined the binding of monoiodinated [Tyr(125I)10]-labeled VIP (125I-VIP) to rat AMs (> 96% pure), obtained from Sprague-Dawley rats by bronchoalveolar lavage (BAL). At 23 degrees C, the interaction of 125I-VIP with AMs was rapid, reversible, saturable, and linearly proportional to the number of cells. At equilibrium, the binding was competitively inhibited by 10(-11)-10(-6) M of native peptide [half-maximal inhibition (IC50) = 0.53 +/- 0.34 nM, n = 8], with evidence for two classes of binding sites: one with a high affinity (Kd = 0.20 +/- 0.09 nM) and a low capacity (1,190 +/- 640 sites/cell) and another with a low affinity (Kd = 43.2 +/- 13.8 nM) and a high capacity (51,700 +/- 14,000 sites/cell). VIP-related peptides inhibited the binding with the order of potency: VIP > peptide histidine isoleucine > helodermin >> secretin; glucagon was ineffective. In the presence of 3-isobutyl-1-methylxanthine, VIP dose dependently stimulated adenosine 3',5'-cyclic monophosphate accumulation in intact AMs, with maximal stimulation (6.3 times basal level) at 1 nM, and half-maximal accumulation at 0.23 +/- 0.11 nM VIP (Kd for high-affinity sites). For determination of the mass of the VIP receptor, 125I-VIP was covalently bound to AMs with the cross-linking agent dithiobis succinimidyl propionate. Autoradiographic studies after sodium dodecyl sulfate/polyacrylamide gel electrophoresis of solubilized affinity-labeled cells revealed a single major band of M(r) 76,400. We conclude that VIP binds to specific receptors on rat AMs that are coupled to adenylate cyclase, through which VIP may modulate inflammatory responses within the lung.

Persistent functional and structural retinal anomalies in newborn rats exposed to hyperoxia

1999 ◽  
Vol 77 (1) ◽  
pp. 48-55 ◽  
Author(s):  
Pierre Lachapelle ◽  
Olga Dembinska ◽  
Luz Marina Rojas ◽  
Julie Benoit ◽  
Guillermina Almazan ◽  
...  
Keyword(s):  
Structural Modification ◽  
Histological Analysis ◽  
Plexiform Layer ◽  
Oscillatory Potentials ◽  
Newborn Rats ◽  
Sprague Dawley ◽  
Structural Modifications ◽  
Retina Development ◽  
Sprague Dawley Rats ◽  
Retinal Disorder

Previous studies have shown that newborn rats exposed postnatally to hyperoxia will develop a permanent impairment of the retinal function as determined with the electroretinogram (ERG). The purpose of our study was to examine whether postnatal hyperoxia equally alters the light- and dark-adapted ERGs and oscillatory potentials (OPs) as well as leads to permanent structural modification of the retina. During the first 14 days of life, cohorts of Sprague-Dawley rats were exposed to a hyperoxic environment, and ERGs were recorded at mean ages of approximately 25 and 55 days. Our results indicate that both light- and dark-adapted ERGs and OPs are already significantly altered within a few days following exposure to hyperoxia. None of the ERG and (or) OP parameters, with the exception of the a-wave, returned to normal values by 55 days of age. In fact some dark-adapted OPs were completely abolished following postnatal O2 exposure. Histological analysis revealed that the retina of rats exposed to hyperoxia failed to develop an outer plexiform layer and had a reduced count of horizontal cells, consistent with the permanent postreceptoral anomalies seen in the ERG responses. Our results suggest that postnatal hyperoxia causes a generalized retinal disorder leading to permanent structural modifications of the retinal cytoarchitecture and lasting anomalies of the rod and cone functions.Key words: rods, cones, electroretinography, oscillatory potentials, hyperoxia, retina, development.

Histological analysis of different local haemostatic agents used for periapical surgery: An experimental study with Sprague‐Dawley rats

2019 ◽  
Vol 45 (3) ◽  
pp. 357-364
Author(s):  
Jesús Mena‐Álvarez ◽  
Norberto Quispe‐López ◽  
Álvaro Zubizarreta‐Macho ◽  
Cristina Rico‐Romano ◽  
Rosa Rodero‐Villanueva ◽  
...  
Keyword(s):  
Experimental Study ◽  
Histological Analysis ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Haemostatic Agents

scholarly journals Diabetes increases brain damage caused by severe hypoglycemia

2009 ◽  
Vol 297 (1) ◽  
pp. E194-E201 ◽  
Author(s):  
Adam J. Bree ◽  
Erwin C. Puente ◽  
Dorit Daphna-Iken ◽  
Simon J. Fisher
Keyword(s):  
Brain Damage ◽  
Histological Analysis ◽  
Neuronal Damage ◽  
Severe Hypoglycemia ◽  
Hippocampal Damage ◽  
Sprague Dawley ◽  
Brain Areas ◽  
Sprague Dawley Rats ◽  
Brain Tissue Damage ◽  
Extent Of Damage

Insulin-induced severe hypoglycemia causes brain damage. The hypothesis to be tested was that diabetes portends to more extensive brain tissue damage following an episode of severe hypoglycemia. Nine-week-old male streptozotocin-diabetic (DIAB; n = 10) or vehicle-injected control (CONT; n = 7) Sprague-Dawley rats were subjected to hyperinsulinemic (0.2 U·kg−1·min−1) severe hypoglycemic (10–15 mg/dl) clamps while awake and unrestrained. Groups were precisely matched for depth and duration (1 h) of severe hypoglycemia (CONT 11 ± 0.5 and DIAB 12 ± 0.2 mg/dl, P = not significant). During severe hypoglycemia, an equal number of episodes of seizure-like activity were noted in both groups. One week later, histological analysis demonstrated extensive neuronal damage in regions of the hippocampus, especially in the dentate gyrus and CA1 regions and less so in the CA3 region ( P < 0.05), although total hippocampal damage was not different between groups. However, in the cortex, DIAB rats had significantly (2.3-fold) more dead neurons than CONT rats ( P < 0.05). There was a strong correlation between neuronal damage and the occurrence of seizure-like activity ( r2 > 0.9). Separate studies conducted in groups of diabetic ( n = 5) and nondiabetic ( n = 5) rats not exposed to severe hypoglycemia showed no brain damage. In summary, under the conditions studied, severe hypoglycemia causes brain damage in the cortex and regions within the hippocampus, and the extent of damage is closely correlated to the presence of seizure-like activity in nonanesthetized rats. It is concluded that, in response to insulin-induced severe hypoglycemia, diabetes uniquely increases the vulnerability of specific brain areas to neuronal damage.

Decellularized Pancreas Matrix Scaffolds for Tissue Engineering Using Ductal or Arterial Catheterization

2018 ◽  
Vol 205 (2) ◽  
pp. 72-84 ◽  
Author(s):  
Javad Hashemi ◽  
Parvin Pasalar ◽  
Masoud Soleimani ◽  
Ehsan Arefian ◽  
Reza Khorramirouz ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Regenerative Medicine ◽  
Islet Cells ◽  
Sodium Dodecyl ◽  
3D Structure ◽  
Sprague Dawley ◽  
Efficient Procedure ◽  
Sprague Dawley Rats ◽  
High Concentrations ◽  
Great Burden

Introduction: Diabetes is known as a worldwide disease with a great burden on society. Since therapeutic options cover a limited number of target points, new therapeutic strategies in the field of regenerative medicine are considered. Bioscaffolds along with islet cells would provide bioengineered tissue as a substitute for β-cells. The perfusion-decellularization technique is considered to create such scaffolds since they mimic the compositional, architectural, and biomechanical nature of a native organ. In this study, we investigated 2 decellularization methods preserving tissue microarchitecture. Methods: Procured pancreas from Sprague-Dawley rats was exposed to different percentages of detergent for 2, 4, and 6 h after cannulation via the common bile duct or aorta. Results: High concentrations of sodium dodecyl sulfate (SDS), i.e., > 0.05%, resulted in tissue disruption or incomplete cell removal depending on the duration of exposure. In both methods, 6-h exposure to 0.05% SDS created a bioscaffold with intact extracellular matrices and proper biomechanical characteristics. Tissue-specific stainings revealed that elastic, reticular, and collagen fiber concentrations were well preserved. Quantitative findings showed that glycosaminoglycan content was slightly different, but hydroxyproline was in the range of native pancreas tissue. Dye infusion through ductal and vascular cannulation proved that the vascular network was intact, and scanning electron microscopy indicated a homogeneous porous structure. Conclusions: Using the detergent-based method, an effective and time-efficient procedure, a whole pancreas extracellular matrix bioscaffold can be developed that can be used as a 3D structure for pancreas tissue engineering-based studies and regenerative medicine applications.

scholarly journals Chronic stress increases the tyrosine phosphorylation in female reproductive organs: An experimental study

2021 ◽  
Author(s):  
Sudtida Bunsueb ◽  
Natthapol Lapyuneyong ◽  
Saranya Tongpan ◽  
Supatcharee Arun ◽  
Sitthichai Iamsaard
Keyword(s):  
Experimental Study ◽  
Tyrosine Phosphorylation ◽  
Chronic Stress ◽  
Cold Water ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Reproductive Organs ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Sds Page

Background: Changes in tyrosine-phosphorylated (TyrPho) protein expressions have demonstrated stress in males. In females, chronic stress (CS) is a major cause of infertility, especially anovulation. However, the tyrosine phosphorylation in the female reproductive system under stress conditions has never been reported. Objective: To investigate the alteration of TyrPho protein expression in ovary, oviduct, and uterus of CS rats. Materials and Methods: In this experimental study, 16 female Sprague-Dawley rats (5 wk: 220-250 gr) were divided into control and CS groups (n = 8/group). Every day, the CS animals were immobilized within a restraint cage and individually forced to swim in cold water for 60 consecutive days. Following the stress induction, the ovary, oviduct, and uterus of all rats were observed for their morphologies. The total protein profiles of all tissues were revealed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) before detecting TyrPho proteins using western blot. Intensity analysis was used to compare the expression of proteins between groups. Results: The results showed that the morphology and weights of ovary and oviduct in the CS group were not different from control. In contrast, the CS significantly increased the uterine weight as compared to control. Moreover, the expressions of TyrPho proteins in the ovary (72, 43, and 28 kDas), oviduct (170, 55, and 43 kDas), and uterus (55, 54, and 43 kDas) were increased in CS group as compared to those of control. Conclusion: The increased expressions of TyrPho proteins in ovary, oviduct, and uterus could be potential markers used to explain some mechanisms of female infertility caused by chronic stress. Key words: Ovary, Oviduct, Uterus, Phosphorylation.

scholarly journals Localization (and profiles) of tyrosinephosphorylated proteins in female reproductive organs of adult rats

2020 ◽  
Vol 47 (3) ◽  
pp. 180-185
Author(s):  
Sudtida Bunsueb ◽  
Nareelak Tangsrisakda ◽  
Alexander T.H. Wu ◽  
Sitthichai Iamsaard
Keyword(s):  
Stromal Cells ◽  
Expression Patterns ◽  
Sodium Dodecyl ◽  
Reproductive Organs ◽  
Uterine Wall ◽  
Apical Surface ◽  
Sprague Dawley ◽  
Adult Rats ◽  
Sprague Dawley Rats ◽  
Estrus Phase

Objective: Tyrosine phosphorylation is an essential process in many biological systems, including the male reproductive system. The presence of tyrosine-phosphorylated (TyrPho) proteins has been well documented in male reproductive organs, but research in fertile females is still limited.Methods: The ovary, oviduct, and uterus of adult female Sprague-Dawley rats in the estrus phase were used to localize TyrPho proteins using an immunohistochemical technique. These proteins were separated and their expression patterns were examined by sodium dodecyl sulfatepolyacrylamide gel electrophoresis and Western blot analysis, respectively.Results: TyrPho proteins were localized in the cytoplasm of the oocyte except the antral fluid; in the granulosa cells, theca cells, and stromal cells of the ovary; at the apical surface of oviductal epithelial cells; and in the basal epithelium and submucosa of the uterine wall. Moreover, we found that 72-, 43-, and 28-kDa TyrPho proteins were localized in the ovary, while 170-, 55-, and 43-kDa proteins were localized in the oviduct. In the uterus, we detected four major bands, corresponding to 61-, 55-, 54-, and 43-kDa TyrPho proteins.Conclusion: Given that these TyrPho proteins were found in major reproductive organs in the estrus phase, these proteins may play important roles in female fertility.

scholarly journals Classification of down-core foraminifera image sets using convolutional neural networks.

2019 ◽  
Author(s):  
Ross Marchant ◽  
Martin Tetard ◽  
Adnya Pratiwi ◽  
Thibault de Garidel-Thoron
Keyword(s):  
Neural Networks ◽  
Convolutional Neural Networks ◽  
Automated Classification ◽  
Deep Convolutional Neural Networks ◽  
The North ◽  
Manual Counting ◽  
North Eastern ◽  
Long Time ◽  
Image Set

Manual identification of foraminifera species or morphotypes under stereoscopic microscopes is time-consuming for the taxonomist, and a long-time goal has been automating this process to improve efficiency and repeatability. Recent advances in computation hardware have seen deep convolutional neural networks emerge as the state-of-the-art technique for image-based automated classification. Here, we describe a method for classifying large down-core foraminifera image set using convolutional neural networks. Construction of the classifier is demonstrated on the publically available Endless Forams image set with an best accuracy of approximately 90%. A complete down-core analysis is performed for benthic species in the Holocene period for core MD02-2518 from the North Eastern Pacific, and the relative abundances compare favourably with manual counting, showing the same signal dynamics. Using our workflow opens the way to automated paleo-reconstruction based on computer image analysis, and can be employed using our labelling and classification software, ParticleTrieur.

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