scholarly journals Új, laparoszkópos beültetésre alkalmas sérvháló állatkísérletes vizsgálata

2016 ◽  
Vol 157 (5) ◽  
pp. 180-184 ◽  
Author(s):  
Péter Marcell Guba

Introduction: Reconstruction of the abdominal wall with mesh is a widely used surgical procedure. The non-absorbable meshes tend to cause numerous side-effects. Aim: The aim of the author was to produce an absorbable, polymer-based mesh that possesses appropriate chemical, mechanical and biological properties. Method: A three-dimensional, biocompatible mesh was produced from poly-vinyl-alcohol using reactive electrospinning. Toxicity and cell-mesh interactions were tested using human lung carcinoma epithelial cells (A-549), and in vivo tests were conducted in 42 male Wistar rats at the 1–5, 7 and 14 postoperative days (3 rats/groups). Results: In the in vitro tests poly-vinyl-alcohol was biocompatible. In the in vivo tests no major complication was associated with the mesh made of poly-vinyl-alcohol. Conclusions: The author concludes that this polymer mesh is biocompatible, it does not damage the surrounding tissues and integrates well with them. Orv. Hetil., 2016, 157(5), 180–184.

1995 ◽  
Vol 23 (4) ◽  
pp. 491-496
Author(s):  
Hanna Tähti ◽  
Leila Vaalavirta ◽  
Tarja Toimela

— There are several hundred industrial chemicals with neurotoxic potential. The neurotoxic risks of most of these chemicals are unknown. Additional methods are needed to assess the risks more effectively and to elucidate the mechanisms of neurotoxicity more accurately than is possible with the conventional methods. This paper deals with general tasks concerning the use of in vitro models in the evaluation of neurotoxic risks. It is based on our previous studies with various in vitro models and on recent literature. The induction of glial fibrillary acidic protein in astrocyte cultures after treatment with known neurotoxicants (mercury compounds and aluminium) is discussed in more detail as an important response which can be detected in vitro. When used appropriately with in vivo tests and with previous toxicological data, in vitro neurotoxicity testing considerably improves risk assessment. The incorporation of in vitro tests into the early stages of risk evaluation can reduce the number of animals used in routine toxicity testing, by identifying chemicals with high neurotoxic potential.


2016 ◽  
Vol 87 (17) ◽  
pp. 2117-2126 ◽  
Author(s):  
Małgorzata Cieślak ◽  
Agnieszka Karaszewska ◽  
Ewa Gromadzińska ◽  
Izabela Jasińska ◽  
Irena Kamińska

The article presents the results of measurements of pressure exerted by two model knitted products – bands with different structure (WI jersey weft-knitted fabric and WII openwork warp-knitted fabric). The tests were carried out with using the I-Scan system (in vivo and in vitro tests) and the STM 579 device (in vitro test). A comparative analysis of the in vivo and in vitro results for the I-Scan method and in vitro results for the I-Scan and STM 579 method was performed. It was found that the pressure values are lower for openwork warp-knitted fabric than for jersey weft-knitted fabric both in the case of the in vitro and in vivo tests, and the values of pressure for the same band are higher in the case of the in vitro tests.


2007 ◽  
Vol 342-343 ◽  
pp. 209-212 ◽  
Author(s):  
Hisatoshi Kobayashi

Previously we have found that the immobilization of Type I collagen on the poly(vinyl alcohol)(PVA) hydrogel disc was effective in supporting adhesion and growth of the corneal epithelium and stromal cell in vitro. But the durability of the produced corneal epithelium layer in vivo has some problem. We hypothesized the cell construction force is much stronger than the force of the cell adhesion on the flat modified PVA surfaces. Therefore the improvement of mechanical anchoring force between the substrate and formed corneal cell layer maybe become one of the solving methods. In this study, we prepared the PVA nanofiber mat by using the electrospinning method and the surface modification of the PVA nanofiber was studied to improve the durability of the corneal epithelium layer. The collagen-immobilized PVA nanofiber sheets could support the adhesion and proliferation of rabbit corneal epithelial cells. And the stratified corneal epithelium structure was observed on the PVA nanofiber sheets when the epithelium was co-cultured with rabbit corneal stromal cells. It means that the corneal epithelium was well differentiated on the collagen immobilized PVA nanofiber sheet. The stability of the corneal epithelium layer on the PVA was dramatically improved; the stratified epithelium layer was kept for two weeks after the differentiation introduction, totally after one month. A light transmittance of these materials is not yet enough. Further study to improve the transmission of light, is required.


2018 ◽  
Vol 41 (8) ◽  
pp. 467-473 ◽  
Author(s):  
Rethinam Senthil ◽  
Robert Berly ◽  
Thimmiah Bhargavi Ram ◽  
Nallathambi Gobi

Purpose: In this study, a blend of synthetic polymer (poly(vinyl) alcohol), natural polymer (collagen type I from fish bone), and graphene oxide nanoparticles is used to fabricate a composite nanofibrous scaffold, by electrospinning, for their potential application in accelerated wound healing. Methods: The scaffold was characterized for its physicochemical and mechanical properties. In vitro studies were carried out using human keratinocyte cell line (HaCaT) which proved the biocompatibility of the scaffold. In vivo study using mice model was carried out and the healing pattern was evaluated using histopathological studies. Results: Scaffold prepared from poly(vinyl) alcohol, collagen type I from fish bone, and graphene oxide possessed better physicochemical and mechanical properties. In addition, in vivo and in vitro studies showed its accelerated wound healing properties. Conclusion: The scaffold with required strength and biocompatibility may be tried as a wound dressing material in large animals after getting necessary approval.


1990 ◽  
Vol 18 (1_part_1) ◽  
pp. 19-22
Author(s):  
Marcel B. Roberfroid ◽  
Fabienne Goethals

Foreword — Animal experimentation is an emotional topic, which arouses passionate feelings both in animal protection groups and in the scientific community. For many years, antivivisectionists have fought for the abolition of all animal experimentation, whereas other groups campaign for suppression/reduction of the level of pain animals suffer because of experimentation. Despite all these efforts, the number of animals used in scientific research does not seem to have decreased significantly during the last few years. At best, this number remains constant or shows minor reductions in some countries, whereas in others it is still increasing. In addition to this situation, which certainly does not satisfy the antivivisectionists, the validity of the use of animal models in biomedical research is increasingly being questioned. On the other hand, a number of developments and projects exist which attest to the growing interest of scientists in in vitro models which use few, or even no, animals. Such a change in attitude is particularly evident in practice and research in toxicology, which uses a large number of animals. Taking into account the special status of toxicology among the biomedical sciences, since its practice is required and defined by laws and directives, a semantic problem exists over which adjective should be applied to describe such new methods. For some, it must be alternative — for consistancy to underline the possibility of replacing classical in vivo tests with new in vitro tests, the validity of which is demonstrated by reference to these in vivo tests. For others, it has to be complementary — to characterise the new protocols and the new experimental models which are of interest, because they contribute to the improvement of toxicology by strengthening its scientific nature. For a third group, it must be adjunct — to emphasise the relatively minor role of non-animal tests in relation to the conventional animal tests. It is the second concept that is favoured in this article. The experimental models to which it applies will, according to the Three Rs of Russell & Burch (1), lead either to the replacement of animal models, or to a reduction in the number of animals used or to refinement of test procedures in order to minimise the suffering and stress caused to animals.


2019 ◽  
Vol 20 (12) ◽  
pp. 2987 ◽  
Author(s):  
Julián Andrés Tamayo Marín ◽  
Sebastián Ruiz Londoño ◽  
Johannes Delgado ◽  
Diana Paola Navia Porras ◽  
Mayra Eliana Valencia Zapata ◽  
...  

Tissue engineering is gaining attention rapidly to replace and repair defective tissues in the human body after illnesses and accidents in different organs. Electrospun nanofiber scaffolds have emerged as a potential alternative for cell regeneration and organ replacement. In this paper, porous membranes, based on nanofibrous chitosan (CS), polyvinyl alcohol (PVA), and graphene oxide (GO), were obtained via electrospinning methodology. Three different formulations were obtained varying GO content, being characterized by Fourier Transform Infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). In vitro tests were carried out, consisting of hydrolytic degradation inside simulated biological fluid (SBF), and in vivo tests were carried out, where the material was implanted in Wistar rats’ subcutaneous tissue to determine its biocompatibility. The antibacterial activity was tested against Gram-positive bacteria Bacillus cereus and Staphylococcus aureus, and against Gram-negative Salmonella enterica and Escherichia coli, by contact of the electrospun nanofiber scaffolds above inoculum bacterial in Müeller Hinton agar with good inhibition only for scaffolds with the higher GO content (1.0%). The results confirmed good biocompatibility of the nanofibrous scaffolds after in vivo tests in Wistar rats, which evidences its high potential in applications of tissue regeneration.


Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2488
Author(s):  
Judith Salas-Oropeza ◽  
Manuel Jimenez-Estrada ◽  
Armando Perez-Torres ◽  
Andres Eliu Castell-Rodriguez ◽  
Rodolfo Becerril-Millan ◽  
...  

Bursera morelensis is used in Mexican folk medicine to treat wounds on the skin. Recently, it was shown that the essential oil (EO) of B. morelensis has wound healing activity, accelerating cutaneous wound closure and generating scars with good tensile strength. α-pinene (PIN) and α-phellandrene (FEL) are terpenes that have been found in this EO, and it has been shown in different studies that both have anti-inflammatory activity. The aim of this study was to determine the wound healing activity of these two terpenes. The results of in vitro tests demonstrate that PIN and FEL are not cytotoxic at low concentrations and that they do not stimulate fibroblast cell proliferation. In vivo tests showed that the terpenes produce stress-resistant scars and accelerate wound contraction, due to collagen deposition from the early stages, in wounds treated with both terpenes. Therefore, we conclude that both α-pinene and α-phellandrene promote the healing process; this confirms the healing activity of the EO of B. morelensis, since having these terpenes as part of its chemical composition explains part of its demonstrated activity.


2011 ◽  
Vol 13 (1) ◽  
pp. 73-83 ◽  
Author(s):  
Ritu Goyal ◽  
Sushil K. Tripathi ◽  
Esther Vazquez ◽  
Pradeep Kumar ◽  
Kailash C. Gupta

2019 ◽  
Vol 28 (1) ◽  
pp. 32-46 ◽  
Author(s):  
Zahra Rafati ◽  
Mohammad Sirousazar ◽  
Zuhair Muhammad Hassan ◽  
Farshad Kheiri

1958 ◽  
Vol 107 (5) ◽  
pp. 711-729 ◽  
Author(s):  
N. Raphael Shulman

Regulated intravenous doses of quinidine were given to patients with the antibody of quinidine purpura to produce controlled thrombocytopenia without clinical sequelae. The degree of thrombocytopenia and the rate at which it developed were dependent on the relative plasma concentration of quinidine and antibody. By relating in vivo changes in platelet levels to concurrent in vitro tests for antibody activity and to quantitative relationships between reactants determined in Papers I and III of this series, it was concluded that the amount of antibody which attaches to platelets when thrombocytopenia develops is insufficient to cause complement fixation or platelet agglutination. Platelets do not appear to be destroyed directly by reaction with antibody in vivo. The minimal amount of antibody which does attach to platelets in vivo appears to increase their susceptibility to the usual mechanisms of sequestration. Megakaryocytes and blood vessels do not appear to be affected directly by the antibody which causes quinidine purpura, and hemorrhagic manifestations of the disease appear to be consequent to changes in platelets alone. A safe method of performing in vivo tests for the presence of an antibody of drug purpura is described. The implications of the present work in idiopathic thrombocytopenic purpura are discussed.


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