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Applicability of thyroxine measurements and ultrasound imaging in evaluations of thyroid function in turtles
2019
Pajdak-Czaus, Joanna | Terech-Majewska, Elżbieta | Będzłowicz, Dagmara | Mączyński, Martyn | Krystkiewicz, Wioletta | Łabuć, Sebastian | Platt-Samoraj, Aleksandra | Szweda, Wojciech
Introduction: The thyroid and parathyroid glands play a major role in maintaining physiological homeostasis in all vertebrates. Reptiles have plasma concentrations of thyroid hormones far lower than mammals. Low levels of these hormones in reptiles impede thyroid hormone detection with assays designed for the higher levels of mammals. The aim of this study was to explore teaming this with ultrasound imaging of the thyroid to appraise glandular function. Material and Methods: Thyroid function of four pond sliders was evaluated based on the results of T4 analyses and ultrasound. Results: The concentrations of T4 varied considerably between the examined animals from <9 nmol/L to >167.3 nmol/L. Ultrasound examination revealed uniform echogenicity and a smooth outline of the thyroid gland in all animals. Conclusion: Monitoring of thyroid function based on T4 and electrolyte concentrations is helpful in assessing the health and living conditions of reptiles, which is important in veterinary practice but problematic. Ultrasound examinations are useful in diagnosing changes in gland structure, such as tumours and goitres, and a combination of both methods supports comprehensive assessments of the anatomy and function of the thyroid gland.
Mostrar más [+] Menos [-]In ovo administration of CpG ODN induces expression of immune response genes in neonatal chicken spleen
2017
Sajewicz-Krukowska, Joanna | Olszewska-Tomczyk, Monika | Domańska-Blicharz, Katarzyna
Introduction: Due to their immunostimulatory properties TLR ligands are used prophylactically to protect against a variety of viral and bacterial pathogens in mammals. Knowledge of the molecular and functional aspects of TLRs is essential for a better understanding of the immune system and resistance to diseases in birds. For that reason, this study attempted to determine the impact of TLR21 stimulation by its synthetic ligand (CpG ODN, class B) on the chicken immune system. Material and Methods: Sixty embryonated chicken eggs were randomly allocated into three groups (control and two experimental groups). On day 18 of embryonic development, chickens in one experimental group were administered in ovo a low dose of CpG ODN and the birds of the second experimental group were given a high dose of the ligand. Spleens were collected at 1, 2, 5, and 10 days post-hatching (dph) for analysis of IFN-α, IFN-β, IFN-γ, IL-6, and IL-10 expression using qRT-PCR. Results: Significant differences were observed in mRNA expression levels of all the measured cytokines associated with the modulation and regulation of the immune response at different time points. Conclusion: The obtained data clearly demonstrate that immune response induction takes place after in ovo administration of class B CpG ODN, and that the ligand has the ability to induce cytokine responses in neonatal chicken spleen.
Mostrar más [+] Menos [-]Characterisation of thrombocytes in Osteichthyes
2019
Stosik, Michał | Tokarz-Deptuła, Beata | Deptuła, Wiesław
Thrombocytes in vertebrates other than mammals, inter alia in fish, are analogues of platelets in mammals. In Osteichthyes, these cells take part in haemostatic processes, including aggregation and release reactions in cases of blood vessel damage, and in the immune response development as well. This paper discusses the development of thrombocytes in Osteichthyes, taking into account the need to make changes to the concept of grouping progenitor cells as suggested in the literature. The following pages present the morphological and cytochemical properties of thrombocytes as well as their defence functions, and also point out differences between thrombocytes in fish and platelets in mammals. The paper further highlights the level of thrombocytes’ immune activity observed in fish and based on an increased proportion of these cells in response to antigenic stimulation, on morphological shifts towards forms characteristic of dendritic cells after antigenic stimulation and on the presence of surface structures and cytokines released through, inter alia, gene expression of TLR receptors, MHC class II protein-coding genes and pro-inflammatory cytokines. The study also points out the need to recognise thrombocytes in Osteichthyes as specialised immune cells conditioning non-specific immune mechanisms and playing an important role in affecting adaptive immune mechanisms.
Mostrar más [+] Menos [-]Cloning and expression of NS3 gene of Pakistani isolate type 2 dengue virus
2018
Yasmin, Farkhanda | Yaqub, Tahir | Idrees, Muhammad | Shahzad, Wasim | Hashmi, Abu Saeed | Aqil, Kiran | Mukhtar, Nadia | Zahoor, Muhammad Yasir | Akhtar, Naeem | Umar, Sajid
Dengue is one of the major emerging viral diseases in the world, with dramatic increases in reported cases in the last few decades and annual worldwide occurrence of approximately 390 million infections. It is a highly important mosquito-vectored disease and is a problem in tropical and subtropical areas of the world. The major aim of this study was to clone and express the dengue NS3 gene, in service to its therapeutic importance for the development of stable cell lines. Blood samples from dengue fever (DF) patients were collected and subjected to PCR amplification of the NS3 gene of dengue virus serotype-2 (DENV-2). The NS3 gene was amplified using gene specific primers and cloned in the TA cloning vectors. The gene was successfully expressed in mammalian expression vector pcDNA3.1. The current finding was different from a previously reported DENV-2 strain replicon constructed in different cells, in which the whole genetic material of the virus was used instead of an active protease gene, and which gave a low yield of replicon expressing cells. Recombinant NS3 could be used to produce an antibody that is possibly helpful for developing a single step diagnostic assay to detect the dengue virus NS3 antigen in sera of dengue patients.
Mostrar más [+] Menos [-]H9N2 avian influenza virus retained low pathogenicity after serial passage in chickens
2018
Jaqede, A. | Fu, Q. | Berhane, Y. | Lin, M. | Kumar, A. | Guan, J.
The H9N2 strains of avian influenza viruses (AIVs) circulate worldwide in poultry and cause sporadic infection in humans. To better understand the evolution of these viruses while circulating in poultry, an H9N2 chicken isolate was passaged 19 times in chickens via aerosol inoculation. Whole-genome sequencing showed that the viruses from the initial stock and those after the 8th and 19th passages (P0, P8, and P19) all had the same monobasic cleavage site in the hemagglutinin (HA), typical for viruses of low pathogenicity. However, at position 226 of the HA protein the ratio of glutamine (which favors avian-type receptor binding) to leucine (which favors mammalian-type receptor binding) decreased from 54:46 in P0, to 87:13 in P8, and then 0:100 in P19. In chickens exposed to aerosols of P0, P8, or P19, replication of the viruses was similar and mainly limited to the respiratory tract. None of the infected chickens showed any clinical signs. Over the 19 passages the viruses maintained relatively stable infectivity but gradually lost lethality to chicken embryos. According to the hemagglutination inactivation assay, P8 was slightly and P19 significantly (P < 0.05) less thermostable than P0. Collectively, after 19 passages in chickens the H9N2 AIVs retained low pathogenicity with a positive selection of L226 in the HA. These findings suggest that H9N2 viruses might acquire mammalian specificity after asymptomatic circulation in avian species.
Mostrar más [+] Menos [-]In vitro characterization of a formulation of butorphanol tartrate in a poloxamer 407 base intended for use as a parenterally administered slow-release analgesic agent
2017
Laniesse, Dalphine | Smith, Dale A. | Knych, Heather K. | Mosley, Cornelia | Sanchez-Migallon Guzman, David | Beaufrere, Huges
OBJECTIVE To assess rheological properties and in vitro diffusion of poloxamer 407 (P407) and butorphanol-P407 (But-P407) hydrogels and to develop a sustained-release opioid formulation for use in birds. SAMPLE P407 powder and a commercially available injectable butorphanol tartrate formulation (10 mg/mL). PROCEDURES P407 and But-P407 gels were compounded by adding water or butorphanol to P407 powder. Effects of various concentrations of P407 (20%, 25% and 30% [{weight of P407/weight of diluent} × 100]), addition of butorphanol, and sterilization through a microfilter on rheological properties of P407 were measured by use of a rheometer. In vitro diffusion of butorphanol from But-P407 25% through a biological membrane was compared with that of a butorphanol solution. RESULTS P407 20% and 25% formulations were easily compounded, whereas it was difficult to obtain a homogenous P407 30% formulation. The P407 was a gel at avian body temperature, although its viscosity was lower than that at mammalian body temperature. The But-P407 25% formulation (butorphanol concentration, 8.3 mg/mL) was used for subsequent experiments. Addition of butorphanol to P407 as well as microfiltration did not significantly affect viscosity. Butorphanol diffused in vitro from But-P407, and its diffusion was slower than that from a butorphanol solution. CONCLUSIONS AND CLINICAL RELEVANCE But-P407 25% had in vitro characteristics that would make it a good candidate for use as a sustained-release analgesic medication. Further studies are needed to characterize the pharmacokinetic and pharmacodynamic properties of But-P407 25% in vivo before it can be recommended for use in birds.
Mostrar más [+] Menos [-]Fluorophotometric determination of aqueous humor flow rates in red-tailed hawks (Buteo jamaicensis)
2012
Jones, Michael P. | Ward, Daniel A.
Objective: To determine aqueous humor flow rate (AHFR) in an avian species by use of anterior segment fluorophotometry. Animals: 9 healthy red-tailed hawks (Buteo jamaicensis; 4 males and 5 females) that ranged from 8 months to 8 years of age. Procedures: A protocol was developed for fluorophotometric determination of AHFR. Topical administration of 10% fluorescein was used to load the corneas, and corneal and aqueous humor fluorescein concentrations were measured approximately 5, 6.5, and 8 hours later. Concentration-versus-time plots were generated, and slopes and cornea-to-aqueous humor concentration ratios from these plots were used to manually calculate flow rates. Results: Mean ± SD AHFRs for the right eye, left eye, and both eyes were 3.17 ± 1.36 μL/min (range, 1.67 to 6.21 μL/min), 2.86 ± 0.88 μL/min (range, 2.04 to 4.30 μL/min), and 2.90 ± 0.90 μL/min (range, 1.67 to 4.42 μL/min), respectively. The AHFRs were similar for right and left eyes. These flow rates represented a mean aqueous humor transfer coefficient of 0.0082/min, which is similar to that of mammalian species. Conclusions and Clinical Relevance: The AHFR in red-tailed hawks was similar to that of most mammalian species, and the fractional egress was almost identical to that of other species. This information will allow a greater understanding of aqueous humor flow in avian eyes, which is crucial when evaluating diseases that affect avian eyes as well as medications that alter aqueous humor flow.
Mostrar más [+] Menos [-]Proto-oncogenes of genomic DNA in clinically normal animals of various species
1991
Miyoshi, N. | Tateyama, S. | Ogawa, K. | Nosaka, D. | Ohashi, T. | Sunyasootcharee, B.
To provide information about oncogenes for molecular biological studies of tumors in domestic animals, theproto-oncogenes homologous to the c-myc, c-erbB-2, c-ros-1, c-yes-1, v-myc, v-Ki-ras, and v-Ha-ras oncogenes of genomic DNA in cattle, horses, pigs, dogs, cats, and chickens were investigated by Southern blot hybridization. High molecular weight genomic DNA in each of the animals contained proto-oncogenes that had a certain homology with the oncogenes used, but the extent of nucleotide homology of the proto-oncogenes differed in number and molecular weight: ie, 1 or 2 bands at 1.6 to 22.0 kilobase (kb) in the c-myc probe, 1 or 2 bands at 1.1 to 16.0 kb in the c-ros-1 probe, 1 to 3 bands at 0.7 to 23.0 kb in the c-erbB-2 probe, 1 to 4 bands at 0.6 to 18.0 kb in the c-yes-1 probe, 1 to 3 bands at 1.6 to 30.0 kb in the v-myc probe, 1 to 7 bands at 1.0 to 36.0 kb in the v-Ki-ras probe, and 1 to 4 bands at 1.0 to 27.0 kb in the v-Ha-ras probe. Furthermore, signal strength of each band, as determined by autoradiography, was not always the same for each probe in the various animals. Our findings indicate that these proto-oncogenes are well conserved with species specificities in each animal.
Mostrar más [+] Menos [-]Non-specific esterase isoenzymes of adult schistosomes from the hippopotamus (Hippopotamus amphibius)
1981
Fripp, P.J.
isoenzyme patterns of extracts of adult schistosomes collected from Hippopotamus amphibius in Kruger National Park compared with similar extracts of adult Schistosoma mansoni and S. rodhaini, characteristics differed suggesting that H. amphibius schistosome is separate species
Mostrar más [+] Menos [-]Clodronate treatment significantly depletes macrophages in chickens
2014
Kameka, Amber M. | Haddadi, Siamak | Jamaldeen, Fathima Jesreen | Moinul, Prima | He, Xiao T. | Nawazdeen, Fathima Hafsa P. | Bonfield, Stephan | Sharif, Shayan | Van Rooijen, Nico | Abdul-Careem, Mohamed Faizal
Macrophages function as phagocytes and antigen-presenting cells in the body. As has been demonstrated in mammals, administration of clodronate [dichloromethylene bisphosphonate (Cl 2MBP)] encapsulated liposomes results in depletion of macrophages. Although this compound has been used in chickens, its effectiveness in depleting macrophages has yet to be fully determined. Here, we show that a single administration of clodronate liposomes to chickens results in a significant depletion of macrophages within the spleen and lungs of chickens up to 4 d post-treatment. This finding suggests that, in order to obtain depletion of macrophages in chickens for greater than 5 d, it is necessary to administer clodronate liposomes 4 d apart. The study also showed that 2 treatments of clodronate liposomes at 4-day intervals resulted in the depletion of macrophages for up to 10 d. The findings of the present study will encourage more precise studies to be done on the potential roles of macrophages in immune responses and in the pathogenesis of microbial infections in chickens.
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