scholarly journals Hydrolytic degradation and in vivo resorption of poly-l-lactic acid-chitosan biomedical devices in the parietal bones of Wistar rats

2019 ◽  
Vol 47 (4) ◽  
pp. 1705-1716
Author(s):  
Carlos Humberto Valencia
Keyword(s):  
Wistar Rats ◽  
Animal Ethics ◽  
Foreign Body Reaction ◽  
Hydrolytic Degradation ◽  
Surface Erosion ◽  
Review Committee ◽  
Mixed Inflammatory Infiltrate ◽  
Response Compatible ◽  
Parietal Bones

Objectives This study sought to describe events related to the degradation/resorption of a device composed of polylactic acid (PLA) after implantation into Wistar rats. Methods Five-millimeter-diameter PLA rigid scaffolds and flexible analogs were elaborated, bioactivated through culture with osteoblasts, and implanted into the parietal bones of adult Wistar rats after 15 days. After 3 months, the samples were recovered and analyzed via optical microscopy (histochemical techniques) and scanning electron microscopy. This research was approved by the animal ethics review committee of Universidad of Valle in Cali, Colombia, according to the endorsement of the ethics committee CEAS 001-016. Results Initially, there was surface erosion and fragmentation of the device, inducing an inflammatory response compatible with the foreign body reaction, in addition to the presence of a pseudocapsule and a mixed inflammatory infiltrate that was responsible for phagocytosis of the material. Regeneration of the defect via the apposition of new bone occurred simultaneously with resorption of the material. Conclusions The results illustrated that the degradation/resorption of PLA occurs in a centripetal pattern.

Oral in vivo Bactofection in Dextran Sulfate Sodium Treated Female Wistar Rats

2010 ◽  
Vol 58 (3) ◽  
pp. 171-176 ◽  
Author(s):  
Roland Pálffy ◽  
Michal Behuliak ◽  
Roman Gardlík ◽  
Peter Jáni ◽  
L'udevít Kádaši ◽  
...  
Keyword(s):  
Wistar Rats ◽  
Dextran Sulfate ◽  
Dextran Sulfate Sodium ◽  
Female Wistar Rats

scholarly journals Effects of systemic glycine on accumbal glycine and dopamine levels and ethanol intake in male Wistar rats

2020 ◽  
Author(s):  
Yasmin Olsson ◽  
Helga Höifödt Lidö ◽  
Klara Danielsson ◽  
Mia Ericson ◽  
Bo Söderpalm
Keyword(s):  
Wistar Rats ◽  
In Vivo Microdialysis ◽  
Ethanol Intake ◽  
Water Model ◽  
Glycine Transporter 1 ◽  
Improved Outcomes ◽  
Male Wistar Rats ◽  
Treatment Principle ◽  
Reward Pathway

AbstractApproved medications for alcohol use disorder (AUD) display modest effect sizes. Pharmacotherapy aimed at the mechanism(s) by which ethanol activates the dopamine reward pathway may offer improved outcomes. Basal and ethanol-induced accumbal dopamine release in the rat involve glycine receptors (GlyR) in the nucleus accumbens (nAc). Glycine transporter 1 (GlyT-1) inhibitors, which raise extracellular glycine levels, have repeatedly been shown to decrease ethanol intake in the rat. To further explore the rational for elevating glycine levels in the treatment of AUD, this study examined accumbal extracellular glycine and dopamine levels and voluntary ethanol intake and preference in the rat, after systemic treatment with glycine. The effects of three different doses of glycine i.p. on accumbal glycine and dopamine levels were examined using in vivo microdialysis in Wistar rats. In addition, the effects of the intermediate dose of glycine on voluntary ethanol intake and preference were examined in a limited access two-bottle ethanol/water model in the rat. Systemic glycine treatment increased accumbal glycine levels in a dose-related manner, whereas accumbal dopamine levels were elevated in a subpopulation of animals, defined as dopamine responders. Ethanol intake and preference decreased after systemic glycine treatment. These results give further support to the concept of elevating central glycine levels to reduce ethanol intake and indicate that targeting the glycinergic system may represent a pharmacologic treatment principle for AUD.

Anti-diabetogenic and in vivo antioxidant activity of ethanol extract of Dryopteris dilatata in alloxan-induced male Wistar rats

Biomarkers ◽  
2021 ◽  
pp. 1-15
Author(s):  
Akpotu E. Ajirioghene ◽  
Samuel I. Ghasi ◽  
Lawrence O. Ewhre ◽  
Olusegun G. Adebayo ◽  
Jerome N. Asiwe
Keyword(s):  
Antioxidant Activity ◽  
Wistar Rats ◽  
Ethanol Extract ◽  
Male Wistar Rats

Physiological and Biochemical Evaluation of the Effectiveness of a New Food Ingredient, a Source of Phytoecdysteroids and Flavonoids from Quinoa Grain

2021 ◽  
Vol 37 (5) ◽  
pp. 88-95
Author(s):  
N.A. Petrov ◽  
S.N. Zorin ◽  
N.A. Biryulina ◽  
V.K. Mazo
Keyword(s):  
Wistar Rats ◽  
Immobilization Stress ◽  
Field Tests ◽  
Physical Exertion ◽  
Biologically Active ◽  
Food Sources ◽  
Food Ingredient ◽  
In Vivo Evaluation ◽  
Russian Scientific

Abstract- One of the promising food sources of biologically active substances is quinoa grain, which is valued for its high content of protein, sulfur-containing amino acids, lysine, fiber, and minerals. In addition, quinoa grain can be a valuable food source of polyphenolic compounds and phytoecdysteroids. The method for production of a concentrate of flavonoids and 20-hydroxyecdysone from quinoa grains sorbed on coagulated egg protein has been developed. The in vivo evaluation of efficacy of the developed food ingredient was conducted using male Wistar rats under immobilization stress and after exhausting physical exertion. The consumption of the food ingredient prevented an increase in the level of the main stress markers, catecholamines, in animals subjected to immobilization stress. The opposite effect was observed in animals that received the food ingredient after exhausting physical exertion: their levels of catecholamines were significantly higher than in the rest comparison groups. Using the Elevated Plus Maze and Open Field tests, it was shown that the consumption of the developed concentrate neutralized the negative effect of immobilization stress and treadmill exercise on anxiety in Wistar rats. The results obtained require additional study under conditions of preventive introduction of the food ingredient into the diet of intact animals, as well as a toxicological safety assessment. Key words: quinoa, 20-hydroxyecdysone, flavonoids, stress, immobilization, exhaustive physical exercise, catecholamines, corticosterone This work was supported by the Russian Scientific Foundation, grant no. 19-16-00107.

Viscoelastic mechanisms of aortic baroreceptor resetting to hypotension and to hypertension

1996 ◽  
Vol 271 (4) ◽  
pp. H1407-H1415 ◽  
Author(s):  
J. Xavier-Neto ◽  
E. D. Moreira ◽  
E. M. Krieger
Keyword(s):  
Wistar Rats ◽  
Temporal Relationship ◽  
Rat Aorta ◽  
Viscoelastic Relaxation ◽  
Phenylephrine Infusion

Viscoelastic and electrophysiological mechanisms have been implicated in the resetting of baroreceptors in hypertension, but resetting in response to hypotension has been less studied. To evaluate the temporal relationship between viscoelastic mechanisms and acute resetting, we examined the “in vivo” behavior of aortic caliber and aortic baroreceptor activity during step changes in pressure. Fifteen-minute hemorrhage in Wistar rats produced stable hypotension (30 mmHg) and viscoelastic contraction (111 +/- 14.2 microns systolic caliber; P < 0.01). Integrated aortic activity fell to 19.8 +/- 3.9% of control (P < 0.001) after 3 s of hypotension but recovered to 64 +/- 4.1% 15 min later (P < 0.01 from 3 s). Recovery of baroreceptor activity was linearly correlated to viscoelastic contraction (r = 0.963; P < 0.0001). Thirty-minute phenylephrine infusion (1.0-4.0 micrograms/min) produced stable hypertension (30 mmHg) and viscoelastic dilation (211 +/- 37.0 microns systolic caliber). Integrated aortic activity increased to 218.0 +/- 18% of control values (P < 0.001) 30 s after hypertension and was reduced to 164.0 +/- 12.0% (P < 0.001 from 3 s) within 30 min. Reduction of baroreceptor activity correlated linearly with viscoelastic relaxation (r = 0.963; P < 0.0001). The results indicate that in the in vivo rat aorta, viscoelastic mechanisms parallel and may contribute to the baroreceptor resetting during hypotension and hypertension.

scholarly journals Safety Evaluation of Multiple Strains ofLactobacillus plantarumandPediococcus pentosaceusin Wistar Rats Based on the Ames Test and a 28-Day Feeding Study

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Cheng-Chih Tsai ◽  
Sew-Fen Leu ◽  
Quan-Rong Huang ◽  
Lan-Chun Chou ◽  
Chun-Chih Huang
Keyword(s):  
Wistar Rats ◽  
Clinical Chemistry ◽  
Toxicity Study ◽  
Bacterial Strains ◽  
Oral Toxicity ◽  
Short Term ◽  
Mutagenic Potential ◽  
Multiple Strains

Three lactic acid bacterial strains,Lactobacillus plantarum, HK006, and HK109, andPediococcus pentosaceusPP31 exhibit probiotic potential as antiallergy agents, both in vitro and in vivo. However, the safety of these new strains requires evaluation when isolated from infant faeces or pickled cabbage. Multiple strains (HK006, HK109, and PP31) were subject to a bacterial reverse mutation assay and a short-term oral toxicity study. The powder product exhibited mutagenic potential inSalmonellaTyphimurium strains TA98 and TA1535 (with or without metabolic activation). In the short-term oral toxicity study, rats received a normal dosage of 390 mg/kg/d (approximately9×109 CFU/kg/d) or a high dosage of 1950 mg/kg/d (approximately4.5×1010 CFU/kg/d) for 28 d. No adverse effects were observed regarding the general condition, behaviour, growth, feed and water consumption, haematology, clinical chemistry indices, organ weights, or histopathologic analysis of the rats. These studies have demonstrated that the consumption of multiple bacterial strains is not associated with any signs of mutagenicity ofS.Typhimurium or toxicity in Wistar rats, even after consuming large quantities of bacteria.

Possible effects of radiofrequency electromagnetic fields on in vivo C6 brain tumors in Wistar rats

2018 ◽  
Vol 140 (3) ◽  
pp. 539-546 ◽  
Author(s):  
Nihal S. Ouadah ◽  
Anthony Lecomte ◽  
Franck Robidel ◽  
Ann Olsson ◽  
Isabelle Deltour ◽  
...  
Keyword(s):  
Brain Tumors ◽  
Electromagnetic Fields ◽  
Wistar Rats ◽  
Radiofrequency Electromagnetic Fields

scholarly journals RADIOLOGICAL STUDY OF MEGACOLON IN TRYPANOSOMA CRUZI INFECTED RATS

2018 ◽  
Vol 31 (1) ◽  
Author(s):  
Carlos Edmundo Rodrigues FONTES ◽  
Ana Paula de ABREU ◽  
Aretuza Zaupa GASPARIM
Keyword(s):  
Trypanosoma Cruzi ◽  
Wistar Rats ◽  
In Vivo Studies ◽  
Proposed Model ◽  
Male Wistar Rats ◽  
Group A ◽  
Time Of Infection ◽  
Group B ◽  
Digital Caliper

ABSTRACT Background: Researches on Chagas disease still use several animals and rats, due to size and susceptibility were preferred by many authors. Aim: To develop an experimental model of megacolon in rats inoculated with the strain Y of Trypanosoma cruzi. Methods: Thirty male Wistar rats were distributed in three groups inoculated with different inoculants: Group A: 600000, Group B: 1000000 and Group C: 1500000 blood trypomastigotes of T. cruzi. Animals were sedated intramuscularly at zero inoculation time (T0) and 60 days after inoculation (T60), to perform the barium enema in order to evaluate the dilatation of the different segments of colon in a comparative study of the measurements obtained, using a digital caliper. Evidence of infection was performed by blood smear collected from the animal’s tail 18 days after inoculation with observation of blood forms. Results: Comparing the intestinal diameter of the inoculated animals with 60,0000 trypomastigotes in the T0 of infection with T60 days after the inoculation, significant dilatation was observed between the proximal, medial and distal segments (p<0.01), indicating the establishment of the megacolon model. In addition, comparing intestinal diameter between the different segments, with in the T0 of infection and the T60 after inoculation, significant alterations were observed (p<0.05). Conclusion: The proposed model was possible for in vivo studies of alterations due to infection by T. cruzi and functional alterations of the colon. In addition, the changes manifested in the colon are not directly proportional to the size of the inoculum, but to the time of infection that the animals were submitted, since the animals inoculated with 60,0000 blood forms were the ones which presented the most significant alterations.

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