scholarly journals Morphological mechanism allowing a parasitic leech, Ozobranchus jantseanus (Rhynchobdellida: Ozobranchidae), to survive in ultra-low temperatures

Biology Open ◽  
2021 ◽  
Author(s):  
Shengli Gu ◽  
Jianjun Liu ◽  
Lei Xiong ◽  
Jinxiu Dong ◽  
Entao Sun ◽  
...  
Keyword(s):  
Survival Rate ◽  
Liquid Nitrogen ◽  
Low Temperatures ◽  
Morphological Changes ◽  
Protective Role ◽  
The Body ◽  
Internal Organs ◽  
Cryoprotective Dehydration ◽  
Posterior Direction ◽  
Anterior Posterior

Ozobranchus jantseanus is the largest metazoan known to survive in liquid nitrogen without pretreatment to date, however, the mechanism underlying this tolerance remains unclear. In this study, the first analyses of histological and morphological changes in normal, frozen, and dehydrated states were performed. Adults survived after direct placement in liquid nitrogen for 96 h, with a survival rate of approximately 86.7%. The leech could withstand rapid desiccation and its survival rate after rehydration was 100% when its water loss was below about 84.8%. After freezing, desiccation, and ethanol dehydration, the leech immediately formed a hemispherical shape. Particularly during drying, obvious transparent glass-like substance was observed on surface. Scanning electron microscopy revealed many pores on the surface of the posterior sucker, creating a sponge-like structure, which may help to rapidly expel water, and a hemispherical shape may protect the internal organs by contraction and folding reconstruction in the anterior-posterior direction. A substantial amount of mucopolysaccharides on the surface and acid cells and collagen fibers in the body, all of which contained substantial polysaccharides, may play a key protective role during freezing. Our results indicate that the resistance of leeches to ultra-low temperatures can be explained by cryoprotective dehydration/vitrification strategies.

scholarly journals Influence of Embedded Fibers and an Epithelium Layer on the Glottal Closure Pattern in a Physical Vocal Fold Model

2014 ◽  
Vol 57 (2) ◽  
pp. 416-425 ◽  
Author(s):  
Yue Xuan ◽  
Zhaoyan Zhang
Keyword(s):  
Vocal Fold ◽  
High Speed ◽  
Critical Role ◽  
Structural Features ◽  
The Body ◽  
Baseline Model ◽  
Cover Layer ◽  
Glottal Closure ◽  
Posterior Direction ◽  
Anterior Posterior

Purpose The purpose of this study was to explore the possible structural and material property features that may facilitate complete glottal closure in an otherwise isotropic physical vocal fold model. Method Seven vocal fold models with different structural features were used in this study. An isotropic model was used as the baseline model, and other models were modified from the baseline model by either embedding fibers aligned along the anterior–posterior direction in the body or cover layer, adding a stiffer outer layer simulating the epithelium layer, or a combination of the 2 features. Phonation tests were performed with both aerodynamic and acoustic measurements and high-speed imaging of vocal fold vibration. Results Compared with the isotropic one-layer model, the presence of a stiffer epithelium layer led to complete glottal closure along the anterior–posterior direction and strong excitation of high-order harmonics in the resulting acoustic spectra. Similar improvements were observed with fibers embedded in the cover layer, but to a lesser degree. The presence of fibers in the body layer did not yield noticeable improvements in glottal closure or harmonic excitation. Conclusion This study shows that the presence of collagen and elastin fibers and the epithelium layer may play a critical role in achieving complete glottal closure.

Peculiarities of the course of radiation-mechanical injuries during modeling of bone-muscular trauma of the limbs in expirement

2020 ◽  
Vol 22 (4) ◽  
pp. 82-86
Author(s):  
S. I. Slukhay ◽  
K. P. Golovko ◽  
I. S. Drachev ◽  
D. V. Remizov
Keyword(s):  
Surgical Treatment ◽  
Soft Tissues ◽  
Morphological Changes ◽  
Mechanical Damage ◽  
The Body ◽  
Acute Radiation ◽  
Weapons Of Mass Destruction ◽  
Internal Organs ◽  
Septic Complications ◽  
Experimental Animals

Experimental data on the course of the wound process and changes in the internal organs of animals during acute radiation sickness are presented. Morphological changes in the wound and with a fracture of the femur, on the model of combined radiation-mechanical conduction in 30 experimental animals (rats). It was found that wounds after primary surgical treatment often suppurate, and the performed osteosynthesis in fractures of tubular bones turns out to be an untenable delivery of metal structures. An unfavorable course of the wound process is noted in the form of pronounced purulent-necrotic changes in soft tissues, which leads to the appearance of degenerative-dystrophic changes in internal organs in experimental animals. The development of the infectious process in the wound, radiation damage is more severe, while the lethality increases by 2023%. The total area and thickness of the newly formed granulation tissue is 1,52 times less than in non-irradiated animals. As a consequence of the disturbance of reparative processes during the development of the mutual burdening syndrome, the consolidation of the fracture with radiation injury to rats was completed in 28,51,2 days, while in non-irradiated animals it was already by 2023 days. The reason for the death of animals is purulent-septic complications in 21 (73%) irradiated rats. Sepsis due to St. aureus was noted in 14 (66,6%) rats and St. epidermalis in 2 (9,5%) animals. Colibacillary sepsis was recorded in 5 (23,8%) rats. Thus, in the conditions of the use of weapons of mass destruction, radiation-mechanical damage will occupy one of the leading places in the structure of sanitary losses. At the same time, the simultaneous effect of radiation and a mechanical factor on the body forms one of the most dangerous variants of damage, in which a favorable outcome is predicted only in milder forms of acute radiation syndrome and provided that surgical treatment is timely.

scholarly journals Postural Preparation to Stepping: Coupled Center of Pressure Shifts in the Anterior-Posterior and Medio-Lateral Directions

2016 ◽  
Vol 54 (1) ◽  
pp. 5-14 ◽  
Author(s):  
Clint Hansen ◽  
Jacques LaRue ◽  
Manh-Cuong Do ◽  
Mark L. Latash
Keyword(s):  
Center Of Pressure ◽  
Initial Conditions ◽  
Force Plate ◽  
Single Step ◽  
The Body ◽  
Lateral Direction ◽  
Postural Adjustments ◽  
Neural Organization ◽  
Posterior Direction ◽  
Anterior Posterior

AbstractWe explored changes in the postural preparation to stepping introduced by modifications of the initial coordinates of the center of pressure (COP). We hypothesized that the postural adjustments in the anterior-posterior direction would persist across all initial COP manipulations while the adjustments in the medio-lateral direction would be highly sensitive to the initial COP coordinate. Healthy subjects stood on a force plate, shifted the body weight to one of the initial conditions that spanned the range of COP coordinates in both directions, and initiated a single step or started to walk. No major changes were observed between the stepping and walking conditions. Changes in the initial COP coordinate in the medio-lateral direction led to scaling of the magnitude of the COP shift in that direction prior to stepping accompanied by a nearly proportional change in the COP shift in the anterior-posterior direction. Changes in the initial COP coordinate in the anterior-posterior direction led to scaling of the magnitude of the COP shift in that direction prior to stepping without consistent changes in the COP shift in the medio-lateral direction. We interpret the results as reflecting a neural organization using a small set of referent body configurations for the postural adjustments.

scholarly journals Modeling of viral-bacterial infections against antibiotic-induced intestinal dysbiosis

2019 ◽  
Vol 25 (2) ◽  
pp. 78-84
Author(s):  
V.V. Bobyr ◽  
L.О. Stechenko ◽  
V.P. Shyrobokov ◽  
О.І. Cryvosheyeva ◽  
О.А. Nazarchuk ◽  
...  
Keyword(s):  
Bacterial Infections ◽  
Morphological Changes ◽  
The Body ◽  
Coxsackie Virus ◽  
Clinical Strain ◽  
Internal Organs ◽  
Intestinal Infections ◽  
Virus Dose ◽  
Significant Difference ◽  
Bacterial Associations

The study of the role of viral-bacterial associations in the etiology of acute intestinal infections is considered new to medical microbiology. The purpose of the study was to determine the effect of viral-bacterial associations on the manifestation of virulence of pathogens and the degree of development of structural-morphological disorders of the internal organs in animals with antibiotic-induced dysbiosis. In a study of 210 white laboratory mice, BALB/c lines formed dysbiosis using antibacterial agents (ampicillin, gentamicin, metronidazole) followed by simulation of the experimental infection. To simulate salmonella infection, mice were infected with a clinical strain of Salmonella typhimurium intraperitoneally. Similarly, the animals were infected with Coxsackie B3 test culture virus (dose 106 TCD50). The sensitivity of mice to Coxsackie B and salmonella viruses was examined for mortality and disease characteristics. The animals were removed from the experiment 24 h after infection, electronically microscopically studied structural and morphological changes of the internal organs were performed. There was no statistically significant difference in morbidity (23.33-26.66 %) and mortality (16.66-20.0 %) of mice infected with Coxsackie virus with dysbiotic disorders and preserved microflora. Dysbiotic conditions have been shown to lead to associated viral-bacterial infections in animals and, accordingly, an increase in the incidence of disease and death in experimental animals. Against the background of disturbance of the composition of the normal intestine microbiota in viral bacterial infections, pronounced degenerative changes in the internal organs of animals were established, with signs of generalization. Electrogram data showed the appearance of activation of immunocompetent cells of the body in viral-bacterial infection in animals with impaired intestine microbiocenosis.

Clinical, morphological and biochemical signs of polymycotoxicosis in highly productive cows

2020 ◽  
pp. 14-17
Author(s):  
Irina A. Shkuratova ◽  
◽  
Lyudmila I. Drozdova ◽  
Aleksander I. Belousov ◽  
Keyword(s):  
Metabolic Disorders ◽  
Hepatorenal Syndrome ◽  
Morphological Changes ◽  
Clinical Manifestations ◽  
The Body ◽  
Feed Mixture ◽  
Milk Productivity ◽  
Structural Disorders ◽  
Increased Sensitivity ◽  
Penicillium Spp

Mycotoxicological monitoring of forages shows that the problem of mycotoxicosis has been relevant for several decades. Minimal doses of mycotoxins in feed lead to a decrease in milk productivity, increased sensitivity to infectious and non-infectious diseases. When several mycotoxins enter the body simultaneously, a synergistic effect develops, causing a significant increase in toxicity. Feed contaminated with several types of fungi and their toxins is dangerous for dairy cattle. It was found that the feed mixture contained the types of associations of Aspergillus spp. fungi + Fusarium; Aspergillus spp. + Penicillium spp. + Mucor spp; Fusarium + Penicillium; Mucor spp. + Fusarium + Ustilaginales. Pathogenetic features of metabolic and morphological changes in highly productive cows with polymycotoxicosis were studied. Feeding food contaminated with various metabolites of mold fungi leads to the development of signs of chronic toxemia in animals. Clinical manifestations are the development of diarrhea and dehydration, with a decrease in milk productivity. Metabolic disorders feature the development of an inflammatory process, metabolic acidosis, hyperfermentonemia, with an increase in the amount of creatinine and urea in the blood serum. Metabolic signs indicate the development of hepatorenal syndrome due to structural disorders of the liver and kidneys. Histological signs of polymicotoxicosis are intracapillary and hemorrhagic glomerulonephritis, hepatocyte micronecrosis, and proliferation of connective tissue stroma cells, which leads to the development of atrophic cirrhosis in the interstitial and circular phases.

Comparative assessment of morphological mechanisms of maintaining structural liver homeostasis in the dynamics of exposure to coal-rock dust and sodium fluoride on the body

2020 ◽  
pp. 189-194
Author(s):  
M. S. Bugaeva ◽  
O. I. Bondarev ◽  
N. N. Mikhailova ◽  
L. G. Gorokhova
Keyword(s):  
Sodium Fluoride ◽  
Morphological Changes ◽  
The Body ◽  
System Level ◽  
Production Factor ◽  
Coal Rock ◽  
The Impact ◽  
Structural Homeostasis ◽  
Rock Dust

Introduction. The impact on the body of such factors of the production environment as coal-rock dust and fluorine compounds leads to certain shift s in strict indicators of homeostasis at the system level. Maintaining the relative constancy of the internal environment of the body is provided by the functional consistency of all organs and systems, the leading of which is the liver. Organ repair plays a crucial role in restoring the structure of genetic material and maintaining normal cell viability. When this mechanism is damaged, the compensatory capabilities of the organ are disrupted, homeostasis is disrupted at the cellular and organizational levels, and the development of the main pathological processes is noted.The aim of the study is to compare the morphological mechanisms of maintaining structural homeostasis of the liver in the dynamics of the impact on the body of coal-rock dust and sodium fluoride.Materials and methods. Experimental studies were conducted on adult white male laboratory rats. Features of morphological mechanisms for maintaining structural homeostasis of the liver in the dynamics of exposure to coal-rock dust and sodium fluoride were studied on experimental models of pneumoconiosis and fluoride intoxication. For histological examination in experimental animals, liver sampling was performed after 1, 3, 6, 9, 12 weeks of the experiment.Results. The specificity of morphological changes in the liver depending on the harmful production factor was revealed. It is shown that chronic exposure to coal-rock dust and sodium fluoride is characterized by the development of similar morphological changes in the liver and its vessels from the predominance of the initial compensatory-adaptive to pronounced violations of the stromal and parenchymal components. Long-term inhalation of coal-rock dust at 1–3 weeks of seeding triggers adaptive mechanisms in the liver in the form of increased functional activity of cells, formation of double-core hepatocytes, activation of immunocompetent cells and endotheliocytes, ensuring the preservation of the parenchyma and the general morphostructure of the organ until the 12th week of the experiment. Exposure to sodium fluoride leads to early disruption of liver compensatory mechanisms and the development of dystrophic changes in the parenchyma with the formation of necrosis foci as early as the 6th week of the experiment.Conclusions. The study of mechanisms for compensating the liver structure in conditions of long-term exposure to coal-rock dust and sodium fluoride, as well as processes that indicate their failure, and the timing of their occurrence, is of theoretical and practical importance for developing recommendations for the timely prevention and correction of pathological conditions developing in employees of the aluminum and coal industry.The authors declare no conflict of interests.

The effectiveness of use of enterosorbent Shelltic Es when rearing of young pigs

2020 ◽  
pp. 3-11
Author(s):  
S. Grikshas ◽  
N. Kulmakova ◽  
K. Spitsyna ◽  
A. Dar’in ◽  
T. Mittelshtein
Keyword(s):  
Average Daily Gain ◽  
Live Weight ◽  
Feed Additives ◽  
The Body ◽  
Control Group ◽  
Internal Organs ◽  
Feed Digestibility ◽  
Young Pigs ◽  
Carcinogenic Effects ◽  
Experimental Group

Mycotoxins have been formed in feed are secondary metabolites of fungi and are quite stable substances that have teratogenic, mutagenic and carcinogenic effects. An effective way to combat mycotoxins in feed is the use of feed additives that adsorb toxins, prevent their absorption in the gastrointestinal tract of the animal and are excreted from the body. The infl uence of coconut enterosorbent Shelltic Es on fattening and meat qualities of young pigs has been studied. It has been found in the process of fattening that the highest feed digestibility was in pigs of the experimental group, in the diet of which enterosorbent has been added. The results of studies of the chemical composition and technological properties of pork have been provided. The positive eff ect of enterosorbent on precocity, absolute average daily gain of live weight and reduction of feed expenditures per 1 kg of gain has been revealed. In pigs from the experimental group the average thickness of the fat was higher and the area of the “muscle eye” was lower compared with animals of the control group, which indicates that higher rates of carcass yield have been obtained due to faster accumulation of fat tissue. The weight of internal organs of pigs indicates the intensity of metabolic processes in the body. In experimental animals the weight of the lungs was 0,1 kg lower, and the liver and heart were higher by 0,13 and 0,01 kg, respectively. Enterosorbent had no effect on the content of vitamins in the liver of pigs of the compared groups. The content of impurities of organochlorine toxicants and toxic elements in the meat and liver of animals of the experimental group was lower than that of control analogues. Therefore, the use of enterosorbent Shelltic Es promotes more active excretion of them from the body.

scholarly journals Ferromagnetic soft catheter robots for minimally invasive bioprinting

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Cheng Zhou ◽  
Youzhou Yang ◽  
Jiaxin Wang ◽  
Qingyang Wu ◽  
Zhuozhi Gu ◽  
...  
Keyword(s):  
Minimally Invasive ◽  
The Body ◽  
Magnetic Actuation ◽  
Internal Organs ◽  
Planar Surfaces ◽  
Reinforced Polymer ◽  
Direct Fabrication ◽  
Digitally Controlled

AbstractIn vivo bioprinting has recently emerged as a direct fabrication technique to create artificial tissues and medical devices on target sites within the body, enabling advanced clinical strategies. However, existing in vivo bioprinting methods are often limited to applications near the skin or require open surgery for printing on internal organs. Here, we report a ferromagnetic soft catheter robot (FSCR) system capable of in situ computer-controlled bioprinting in a minimally invasive manner based on magnetic actuation. The FSCR is designed by dispersing ferromagnetic particles in a fiber-reinforced polymer matrix. This design results in stable ink extrusion and allows for printing various materials with different rheological properties and functionalities. A superimposed magnetic field drives the FSCR to achieve digitally controlled printing with high accuracy. We demonstrate printing multiple patterns on planar surfaces, and considering the non-planar surface of natural organs, we then develop an in situ printing strategy for curved surfaces and demonstrate minimally invasive in vivo bioprinting of hydrogels in a rat model. Our catheter robot will permit intelligent and minimally invasive bio-fabrication.

scholarly journals Electrocution Stigmas in Organ Damage: The Pathological Marks

Diagnostics ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 682
Author(s):  
Gelsomina Mansueto ◽  
Mario Di Napoli ◽  
Pasquale Mascolo ◽  
Anna Carfora ◽  
Pierluca Zangani ◽  
...  
Keyword(s):  
Morphological Changes ◽  
Organ Damage ◽  
Pathological Findings ◽  
Internal Organs ◽  
Histological Changes ◽  
Morphological Findings ◽  
Starting Point ◽  
Autopsy Series ◽  
Golden Standard ◽  
Wide Variability

Background: Diagnostic criteria for electrocution related death are still a challenge in forensic pathology and it seems that the electrical mark is the only reliable evidence. Methods: A comparison of histological and morphological findings of skin and internal organs from an autopsy series of electrocution deaths with those mostly reported in literature as representative for electrocution. Results: The morphological changes of heart, brain and other main internal organs are still unspecific. Organ’s damage observed in electrocution deaths shows a wide variability, not reliable for a certain diagnosis of electrocution. The electrical mark is still the golden standard for diagnosis of electrocution. Conclusions: In electrocution related deaths, pathological findings of the main internal organs are not enough evidence to support with certainty a post-mortem diagnosis that a victim suffered an electrical damage. Although the organ histological changes are undoubtedly the starting point for a better understanding of the fatal even, the diagnosis of death from electrical damage is still a dark and unsolved chapter. The electrical mark still represents a fundamental indicator above all in the medical-legal field, but the identification of pathognomonic elements and signs not limited to the skin alone could be a valid help in the future, especially in unclear cases.

scholarly journals Interactions between the WEE-1.3 kinase and the PAM-1 aminopeptidase in oocyte maturation and the early C. elegans embryo

2021 ◽  
Author(s):  
Dorothy Benton ◽  
Eva C Jaeger ◽  
Arielle Kilner ◽  
Ashley Kimble ◽  
Josh Lowry ◽  
...  
Keyword(s):  
Missense Mutation ◽  
Oocyte Maturation ◽  
Protective Role ◽  
C Elegans ◽  
Direct Target ◽  
The One ◽  
Actomyosin Cytoskeleton ◽  
Embryonic Viability ◽  
Anterior Posterior

Abstract Puromycin-sensitive aminopeptidases are found across phyla and are known to regulate the cell-cycle and play a protective role in neurodegenerative disease. PAM-1 is a puromycin-sensitive aminopeptidase important for meiotic exit and polarity establishment in the one-cell Caenorhabditis elegans embryo. Despite conservation of this aminopeptidase, little is known about its targets during development. In order to identify novel interactors, we conducted a suppressor screen and isolated four suppressing mutations in three genes that partially rescued the maternal-effect lethality of pam-1 mutants. Suppressed strains show improved embryonic viability and polarization of the anterior-posterior axis. We identified a missense mutation in wee-1.3 in one of these suppressed strains. WEE-1.3 is an inhibitory kinase that regulates maturation promoting factor. While the missense mutation suppressed polarity phenotypes in pam-1, it does so without restoring centrosome-cortical contact or altering the cortical actomyosin cytoskeleton. To see if PAM-1 and WEE-1.3 interact in other processes, we examined oocyte maturation. While depletion of wee-1.3 causes sterility due to precocious oocyte maturation, this effect was lessened in pam-1 worms, suggesting that PAM-1 and WEE-1.3 interact in this process. Levels of WEE-1.3 were comparable between wild-type and pam-1 strains, suggesting that WEE-1.3 is not a direct target of the aminopeptidase. Thus, we have established an interaction between PAM-1 and WEE-1.3 in multiple developmental processes and have identified suppressors that are likely to further our understanding of the role of puromycin-sensitive aminopeptidases during development.

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