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The preventive role of Spirulina platensis (Arthrospira platensis) in immune and oxidative insults in a stress-induced rat model Texte intégral
2021
Seyidoğlu, Nilay | Köşeli, Eda | Gurbanlı, Rovshan | Aydın, Cenk
There is a balance between oxidative stress, antioxidant capacity and immune response. Their roles in physiological and behavioural mechanisms are important for the maintenance of the organism’s internal equilibrium. This study aimed to evaluate the antioxidant effects of the exogenous alga Spirulina platensis (Arthrospira platensis) in a stress-induced rat model, and to describe its possible mechanism of action. Thirty-six adult male Sprague Dawley rats were separated into four groups: control (C), stress (S), S. platensis (Sp), and S. platensis + stress (SpS). The rats in groups Sp and SpS were fed with 1,500 mg/kg b.w./day Spirulina platensis for 28 days. All rats were exposed to prolonged light phase conditions (18 h light : 6 h dark) for 14 days. The SpS and S groups were exposed to stress by being kept isolated and in a crowded environment. Blood samples were obtained by puncturing the heart on the 28th day. The effect of stress on serum corticosterone, oxidative stress markers (TOS, TAC, PON1, OSI) and immunological parameters (IL-2, IL-4, IFN-ɣ) were tested. Also, the brain, heart, intestines (duodenum, ileum, and colon), kidney, liver, spleen, and stomach of the rats were weighed. Serum corticosterone levels were higher in the S group than in the C group, and significantly lower in the SpS group than in the S group. Mean total antioxidant capacity were lower in the S group than in the C group, and Spirulina reversed this change. Although not significantly different, IL-2 was lower in the S group than in the C group. However, in the SpS group, IL-2 increased due to Spirulina platensis mitigating effects of stress. Male rats fed a diet with Spirulina platensis could experience significantly milder physiological changes during stress, although stress patterns may be different. Exogenous antioxidant supplements merit further investigation in animals and humans where the endogenous defence mechanism against stress may not be sufficient.
Afficher plus [+] Moins [-]Seroprevalence of feline foamy virus in domestic cats in Poland Texte intégral
2021
Materniak-Kornas, Magdalena | Frymus, Tadeusz | Löchelt, Martin | Kuźmak, Jacek
Feline foamy virus (FFVfca) is widespread and its prevalence in naturally infected domestic cats ranges between 30% and 80% worldwide. The infection is persistent, with a sustained antibody response in FFVfca-positive cats; however to date, no defined disease or clinical symptoms have been proved to be associated with it. The goal of the presented study was to determine the prevalence of FFVfca infection in domestic cats in Poland. A total of 223 serum samples collected from domestic cats were tested with a glutathione S-transferase capture ELISA test to detect antibodies specific to capsid (Gag), accessory (Bet) and envelope (Env) FFVfca antigens. A Western blot test was used to confirm the ELISA results. The cut-off value for the Gag antigen was established by calculation and evaluation with the immunoblotting assay. The cut-off values for Bet and Env were calculated from the reactivity of Gag-negative samples. The sera of 99 cats (44%) showed reactivity to Gag, those of 80 did so (35.9 %) to Bet, while only 56 samples (25%) were reactive to Env. Only 51 (22.9%) sera were positive for all antigens. The main diagnostic antigen was selected to be Gag. A statistically significant association was found between FFVfca status and the age of the cat. This study proved the high seroprevalence of FFVfca in domestic cats in Poland for the first time and confirmed that adult cats are at higher FFVfca infection risk than preadult cats. Its results correspond to those reported from other countries.
Afficher plus [+] Moins [-]Therapeutic effects of revascularisation on the healing of free bone grafts in dogs Texte intégral
2020
Zheng, Jia-San | Ruan, Hong-Ri | Shuang-Qiu, | Jing-Nie, | Hou, Kai-Wen | Rui-Wu,
The therapeutic effect of subcutaneous embedding and revascularisation on the repair of canine bone defects caused by open fracture was examined. A total of 12 adult beagle dogs were randomly split into a control group (group C) and a test group (group T). A section of the radius was removed from each dog under general anaesthesia and the deficit supported by an orthopaedic implant. Group T had the section surgically implanted next to the blood vessel–rich saphenous vein and Group C had it cryopreserved at −80°C. After eight weeks, the bone was surgically implanted back into the matching radial deficit. Bone healing was evaluated by gross morphological and X-ray examinations, post-mortem histology, and successive blood measurements of key bone biochemical markers. At 12 weeks, the bone healing boundary was disappearing more quickly in group T dogs than in their group C counterparts. X-ray and histological examinations showed that the cortical repair of group T subjects was complete and the bony plate arrangement was more regular than that in group C. The levels of bone biochemical markers also proved that the healing state of group T was better. The results showed that the degree of healing, osteoclast activity, and bone formation status of group T were better than those of group C, proving that the vascularised bone graft had a significantly shorter healing time than the cryopreserved bone graft.
Afficher plus [+] Moins [-]Occurrence of gastrointestinal parasites in camels in the Tianshan Mountains pastoral area in China Texte intégral
2020
Guowu, Zhang | Kai, Zhang | Xifeng, Wang | Chunhui, Ji | Chengcheng, Ning | Yue, Zhao | Jun, Qiao | Qingling, Meng | Xingxing, Zhang | Kuojun, Cai | Jinsheng, Zhang | Zaichao, Zhang | Xuepeng, Cai
Gastrointestinal parasites are some of the most common pathogens which are seriously harmful to the camel’s health. The infection status of gastrointestinal parasites in camels (Camelus bactrianus) in the Tianshan Mountains pastoral area in China is still unclear. The aim of this study was to investigate the species and infection intensity of gastrointestinal tract parasites in local camels. A total of 362 fresh faecal samples were collected and examined for parasite eggs using the saturated saline floating and natural sedimentation method. The parasite eggs were subjected to morphological and molecular examination and identification, and the infection rate and mean intensity of the parasites were analysed. A total of 15 gastrointestinal tract parasite species’ eggs were identified, with a detection rate of 100%. Ostertagia spp. (100%) and Trichostrongylus spp. (98.1%) were dominant. Camels were often coinfected by 5–14 species. The average number of eggs per gram of faeces was higher for Ostertagia spp. (298), Haemonchus contortus (176) and Nematodirus spp. (138). The number of species of parasites infecting young camels was significantly lower than that of adult camels, but the infection intensity in young camels was significantly higher. Gastrointestinal parasites were highly prevalent in camels from the Tianshan Mountains pastoral area in China. This finding provides important epidemiological data for the prevention and control of associated infections in camels.
Afficher plus [+] Moins [-]Pituitary-testicular axis dysfunction in methimazole-induced hypothyroidism in rats Texte intégral
2019
Gołyński, Marcin | Metyk, Michał | Szkodziak, Piotr | Lutnicki, Krzysztof | Kalisz, Grzegorz | Szczepanik, Marcin | Wilkołek, Piotr | Dobrowolski, Piotr
Introduction: Thyroid hormones play a major role in the regulation of testicular maturation and growth and in the control of Sertoli and Leydig cell functions in adulthood. When naturally occurring, hypothyroidism causes male hypogonadotropic hypogonadism and Sertoli cell function disorders, but when iatrogenic and methimazole-induced its influence on the pituitary-testicular axis function with respect to Sertoli cells is poorly known. Material and Methods: Male adult Wistar rats (n = 14) were divided into two groups: E – taking methimazole orally for 60 days, and C – control animals. After 60 d, the concentrations in serum of testosterone, follicle-stimulating and luteinising hormones, and inhibins A and B were measured. Testicles were examined morphologically: the apoptotic Sertoli cell percentage (ASC%) and number of these cells functional per tubular mm² (FSCN/Tmm²) were calculated. Results: In group E, inhibin A was higher while inhibin B was lower than in group C. ASC% was higher and FSCN/Tmm² lower in group E than in group C. Conclusion: A specific modulation of Sertoli cell function in the course of methimazole-induced hypothyroidism leads to a simultaneous concentration increase in inhibin A and decrease in B. Inhibin A might share responsibility for pituitary-testicular axis dysfunction and hypogonadotropic hypogonadism in this model of hypothyroidism.
Afficher plus [+] Moins [-]Histopathological evaluation of polycaprolactone nanocomposite compared with tricalcium phosphate in bone healing Texte intégral
2018
Eftekhari, Hadi | Jahandideh, Alireza | Asghari, Ahmad | Akbarzadeh, Abolfazl | Hesaraki, Saeed
In recent years, the use of bone scaffolds as bone tissue substitutes, especially the use of such as hydroxyapatite and tricalcium phosphate, has been very popular. Today, the use of modern engineering techniques and advances in nanotechnology have expanded the use of nanomaterials as bone scaffolds for bone tissue applications. This study was performed on 60 adult male New Zealand rabbits divided into four experimental groups: the control group without any treatment, the second group receiving hydroxyapatite, the third group treated with β-tricalcium phosphate, and the fourth group receiving nanocomposite polycaprolactone (PCL) scaffold. In a surgical procedure, a defect 6 mm in diameter was made in a hind limb femur. Four indexes were used to assess histopathology, which were union index, spongiosa index, cortex index, and bone marrow. The results showed that nanocomposite PCL and control groups always had the respective highest and lowest values among all the groups at all time intervals. The histopathological assessment demonstrated that the quantity of newly formed lamellar bone in the nanocomposite PCL group was higher than in other groups. All these data suggest that PCL had positive effects on the bone healing process, which could have great potential in tissue engineering and clinical applications.
Afficher plus [+] Moins [-]Red foxes (Vulpes vulpes) as reservoirs of respiratory capillariosis in Serbia Texte intégral
2016
Ilić, Tamara | Becskei, Zsolt | Tasić, Aleksandar | Stepanović, Predrag | Radisavli︠e︡vich Katarina, | Đurić, Boban | Dimitrijević, Sanda
Introduction: The aim of the study was to determine the prevalence of respiratory capillariosis in red foxes (Vulpes vulpes) in some regions of Serbia.Material and Methods: The study was conducted on 102 foxes in six epizootiological regions of Serbia, during the hunting season between 2008 and 2012.Results: The presence of respiratory capillariosis in all tested epizootiological regions was confirmed. The E. aerophilus nematode was detected with overall prevalence of 49.02%. The diagnosis of E. aerophilus infection was confirmed by the determination of morphological characteristics of adult parasites found at necropsy and the trichurid egg types collected from the bronchial lavage and the content of the intestine.Conclusion: The presented results contribute to better understanding of the epidemiology of this nematodosis in Serbia. However, the high prevalence of capillaries in tested foxes, demonstrated in all explored areas, might suggest that foxes from other regions in Serbia may also be infected. The fact that domestic carnivores and humans can also be infected enhances the importance of the overall epidemiological status. To establish the relevant prevalence of respiratory capillariosis, further investigations and continous monitoring of parasitic fauna of carnivores are needed in the whole country.
Afficher plus [+] Moins [-]A preliminary study on semen collection, its evaluation, and testicular and sperm morphometries in the wild proboscis monkey (Nasalis larvatus) Texte intégral
2021
Zainuddin, Zainal Zahari | Tarmizi, Mohamed Reza Mohamed | Chee, Yap Keng | Erut, Alvin | Fitri, Wan Nor | Salleh, Annas
The proboscis monkey (Nasalis larvatus) is an endangered species with a declining population. This article describes the first successful attempt at sperm collection and evaluation, and the testicular and sperm morphometries of the wild proboscis monkey in Sabah, Malaysia. Eight semen collection procedures using electro-ejaculation and digital manipulation were conducted in three wild adult male proboscis monkeys. A total of 21 ejaculates were collected. The testicular biometry was measured with the aid of ultrasonography. Sample evaluation included semen volume and pH and sperm concentration, viability, and abnormality. The sperm morphometry was undertaken using phase contrast microscopy. The mean (±SD) total testicular volume of these animals was 5.77 cm³ (±1.58). Semen collection by electro-ejaculation resulted in an 84% success rate, while digital manipulation did not result in any ejaculation. Each animal showed different semen characteristics, where the volume was 5–540 μL, pH 8–9, and sperm concentration 0.041–83.00 ×106/mL. The percentage of abnormal sperm was high at 76.8% (±89.60), largely due to midpiece abnormality. Normal sperm had a spherical head and long tail with a head : midpiece : tail length ratio of 1 : 2: 8. The social status of these animals may contribute to the generally low quality of the semen. The techniques and data from this study are useful for future conservation and application of assisted reproductive technology in this species.
Afficher plus [+] Moins [-]Fasciola hepatica isolates induce different immune responses in unmaturated bovine macrophages Texte intégral
2019
Bąska, Piotr | Zawistowska-Deniziak, Anna | Norbury, Luke James | Wiśniewski, Marcin | Januszkiewicz, Kamil
Introduction: Fasciola hepatica (liver fluke) is a parasite of great socioeconomic importance. A number of fluke isolates have been identified; however, to date the differences between the immunomodulatory properties of different parasite isolates have not been sufficiently investigated. The aim of this study was to explore differences between the immunomodulatory properties of two F. hepatica isolates using unmaturated bovine macrophages. Material and Methods: A cell line of bovine macrophages was stimulated with excretory/secretory products released by adult flukes from either a laboratory (Fh-WeyES) or wild (Fh-WildES) strain and subsequently subjected to microarray and ELISA analyses. Results: Both Fh-WeyES and Fh-WildES dampened the release of interleukin-10 by bovine macrophages, but only Fh-WildES dampened the release of proinflammatory tumour necrosis factor-α. Microarray analysis revealed that Fh-WildES down- and upregulated 90 and 18 genes, respectively, when compared to Fh-WeyES. Conclusion: The results indicated different impacts of the isolates on macrophages. A number of researchers use flukes obtained from local slaughterhouses for experiments. Our findings may explain some discrepancies between published results arising from parasite strain choice. The findings indicate that consideration should be given to the use of different strains, and open new and currently unexplored avenues in parasitology for controlling the parasite.
Afficher plus [+] Moins [-]Prevalence of Borrelia burgdorferi sensu lato in ticks from the Ternopil region in Ukraine Texte intégral
2018
Lyme borreliosis/Lyme disease is caused by Borrelia burgdorferi and is one of the most common vector-borne diseases transmitted by ticks. A total of 136 Ixodes ricinus ticks, collected in the Ternopil (Ukraine) region, including 126 adults (70 females and 56 males), and 10 nymphs were examined. The identification of the species and their developmental form was based on morphological characteristics. PCR with B5S-Bor and 23S-Bor primers resulted in Borrelia burgdorferi sensu lato DNA amplification among six ticks (4.4%). The detailed analysis based on the DNA sequencing showed the presence of DNA of Borrelia afzelii in four samples; the remaining two represented Borrelia burgdorferi sensu lato complex, although their genospecies were not determined. The research confirmed the dominance of Borrelia afzelii genospecies in the ticks from Ukraine. It seems reasonable to undertake similar research in ticks from other regions of Ukraine. Knowledge in this field can be useful for public health and planning the prevention of tick-borne diseases.
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