خيارات البحث
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Effect of cytochrome P450 inhibition on toxicity of diclofenac in chickens: Unravelling toxicity in Gyps vultures
2022
Sara Locke | Vinny Naidoo | Ibrahim Hassan | Neil Duncan
Diclofenac was responsible for the decimation of Gyps vulture species on the Indian subcontinent during the 1980s and 1990s. Gyps vultures are extremely sensitive (the lethal dose 50 [LD50] ~ 0.1 mg/kg – 0.2 mg/kg), with toxicity appearing to be linked to metabolic deficiency, demonstrated by the long T1/2 (~12 h – 17 h). This is in striking comparison to the domestic chicken (Gallus gallus domesticus), in which the LD50 is ~10 mg/kg and the T1/2 is ~1 h. The phase 1 cytochrome P450 (CYP) 2C subfamily has been cited as a possible reason for metabolic deficiency. The aim of this study was to determine if CYP2C9 homolog pharmacogenomic differences amongst avian species is driving diclofenac toxicity in Gyps vultures. We exposed each of 10 CYP-inhibited test group chickens to a unique dose of diclofenac (as per the Organisation for Economic Co-operation and Development [OECD] toxicity testing guidelines) and compared the toxicity and pharmacokinetic results to control group birds that received no CYP inhibitor. Although no differences were noted in the LD50 values for each group (11.92 mg/kg in the CYP-inhibited test group and 11.58 mg/kg in the control group), the pharmacokinetic profile of the test group was suggestive of partial inhibition of CYP metabolism. Evaluation of the metabolite peaks produced also suggested partial metabolic inhibition in test group birds, as they produced lower amounts of metabolites for one of the three peaks demonstrated and had higher diclofenac exposure. This pilot study supports the hypothesis that CYP metabolism is varied amongst bird species and may explain the higher resilience to diclofenac in the chicken versus vultures.
اظهر المزيد [+] اقل [-]Invastigation of 16S rRNA, mecA and nuc genes in coagulase-positive and negative Staphylococci by Real-Time PCR
2022
Aksakal, Abdulbaki | Onalan, Sukru | Okali̇n, Seyda Silan
Staphylococcus aureus is a Gram-positive and round-shaped bacterium. It is often positive for catalase and nitrate reduction. Pathogenic isolates support infections by producing protein toxins and the expression of a cell-surface protein virulence factors. Sepsis-related to methicillin-resistant S. aureus (MRSA) has significant morbidity and high mortality rates (15-30%). The methicillin resistance for S. aureus is coded with the MecA gene, while the methicillin sensitivity is coded with the Nuc gene, and they are chromosomal. Similarly, it is coded with the coagulase gene for S. aureus (Coa). In this study, the 16S rRNA gene identification by Real-Time PCR was investigated in forty S. aureus isolates, which were cultured at different times in terms of MIC and SIR tests. The isolates used in the study were determined at the gene level in terms of their differences in methicillin resistance gene (MecA), methicillin susceptibility gene (Nuc), coagulase gene (Coa) and intraspecies differences were examined.As a result of the study, Staphylococcus spp. yielded positive results with 16S rRNA gene-specific primers in all isolates. Real-Time PCR analysis of the isolates with SYBRGreen-based PCR analysis was performed with 16S rRNA gene-specific primers, and the samples were confirmed to be Staphylococcus. Analysis at the family level was followed by Coa, Nuc, and MecA gene Real-Time PCR results, and it was found that, in terms of Coa and Nuc genes, 19 isolates were positive and 21 isolates were negative. In terms of MecA gene, 16 isolates were positive according to the positive sigmoidal curves and to the single peak melting values, whereas 24 isolates were found to be negative.It is thought that this study will benefit the community by contributing to the rapid and effective treatment and diagnosis of infections caused by coagulase-positive/negative Staphylococci.
اظهر المزيد [+] اقل [-]Comparison of fertility parameters in Romanov sheep synchronized with progesterone-based protocol plus PMSG or GnRH
2022
Guner, Barıs | Karakaya Bi̇len, Ebru
The aim of this study was to compare the fertility parameters in response to pregnant mare serum gonadotropin (conventional treatment) or gonadotrophin-releasing hormone (alternative treatment) in Romanov sheep subjected to a 7-d short-term protocol during non-breeding season. All sheep (n:57) were subjected to short-term synchronization protocol. Intravaginal sponge impregnated with 20 mg fluorogestone acetate was inserted for 7 days and all sheep received 125 µg cloprostenol at sponge removal. Sheep were randomly assigned to receive no additional treatment (CON, n:16), 240 IU pregnant mare serum gonadotropin (PMSG, n:24) at sponge removal or 10 µg buserelin acetate (GnRH, n:17) at 30 h after sponge removal. Natural mating was performed following detection of estrous with fertile eight Romanov rams. Estrous response, pregnancy rate, lambing rate, and litter size were compared among groups. Estrous response and pregnancy rate were 86% and 75.4% in all sheep, respectively. Estrous response was numerically higher about 7% (p>0.05) in treatment groups (PMSG, 87.5%; GnRH, 88.2%) than CON (81.2%). However, pregnancy rate was numerically higher (p>0.05) in PMSG (83.3%) than GnRH (70.6%) and CON (68.7%). Similarly, lambing rate in the PMSG (79.1%) was approximately 15% numerically greater (p>0.05) than in GnRH (64.7%) and CON (62.5%). In addition, litter size in PMSG (2.1) was also numerically higher (p>0.05) than GnRH (1.9) and CON (1.9).The use of GnRH provided similar estrous response compared to use of PMSG in Romanov sheep synchronized with short-term protocol. However, use of PMSG provided numerically higher pregnancy rate, lambing rate, and litter size than use of GnRH. Considering the serious ethical concerns and animal welfare for the production of PMSG, it is necessary to use alternative gonadotropins. Comprehensive studies are needed to compare the fertility parameters between application of PMSG and GnRH in Romanov sheep.
اظهر المزيد [+] اقل [-]The Molecular Biology of Apoptosis
2022
Beyhan Yilmaz, Melisa | Muz, Dilek
Apoptosis, also known as programmed cell death, has become a target for treating many diseases, especially cancer. Many factors are influential in the cell's pathway to apoptosis. The defects in these pathways may transform the cell to become malignant, and the organism may face a lethal outcome such as cancer. Understanding apoptosis will provide clues in guiding the pathogenesis of diseases. Two main pathways leading to apoptosis, intrinsic and extrinsic, take an active role. The granzyme B pathway is also considered an apoptotic pathway, and this pathway is activated by enzymes secreted by immune cells such as T and NK. Many caspase molecules have initiator and enforcer roles and are active at critical points in the cell's apoptosis process. In cancer treatments, activating molecules in these pathways and repairing disrupted pathways are among the target approaches. This review discusses target strategies for inhibiting apoptotic pathways and molecules in cancer cells and activating these apoptotic pathways.
اظهر المزيد [+] اقل [-]Cutaneous metastasis of mammary gland tumor in a dog: a case report
2022
Choi, H.J. | Na, H.M. | Lee, S.K. | Bae, S.G. | Oh, T.H. | Lee, K.J.
An 8-year-old spayed female, mixed dog presented multiple, bloody exudative skin lesions on the bilateral flank which spread 1 week after mastectomy for treatment of mammary gland tumor (MGT). Multiple, ill-marginated, irregular, and heterogeneously thickened cutaneous and subcutaneous lesions and enlarged lymph nodes were identified in ultrasound and computed tomography. Histopathological examination confirmed adenocarcinoma with lymphatic invasion presumed to be metastatic MGT. Clinical signs improved after chemotherapy but died after 1 month. This study suggests that cutaneous metastasis be considered for differential diagnosis of cutaneous lesions in dogs with a history of MGT, although skin metastasis from MGT is rare.
اظهر المزيد [+] اقل [-]Synergistic anticancer activity of disulfiram/copper against mouse lymphoma cells
2022
Jung, H.B. | Joo, H.G.
Disulfiram (DSF) is a marketed drug to treat patients with alcohol dependence by inhibiting aldehyde dehydrogenase. Over the last few decades, DSF has been shown to have anticancer effects through different mechanisms. Moreover, this effect can be elevated when used with copper (Cu). Subsequent studies have been conducted on various cancers, but few on lymphoma. This study investigated the anticancer effects of DSF on lymphoma and how this effect changed when treated with Cu. DSF synergistically decreased the metabolic activity of EL4 lymphoma cells when combined with Cu. At 1 µM of DSF alone, the metabolic activity of EL4 cells decreased by 49% compared to the control, whereas it decreased by 87% with a DSF + CuCl₂ treatment. Rhodamine 123 and 2’,7’-dichlorofluorescein diacetate staining showed that DSF induced the reduction of the mitochondrial membrane potential and promoted the production of reactive oxygen species. In particular, the combined treatment of DSF + Cu induced cell death based on multiple assays, including annexin V-fluorescein isothiocyanate/propidium iodide staining. Overall, DSF has anticancer effects on lymphoma cells and exhibits synergistic effects when combined with Cu. This study provides some valuable information to broaden the use of DSF in clinics and basic research.
اظهر المزيد [+] اقل [-]Fatal pneumonia caused by extraintestinal pathogenic Escherichia coli in a young dog
2022
Kim, G.Y. | Kim, J.H. | Lee, H.K. | Kim, H.Y. | Moon, B.Y. | Lee, Y.R. | Park, J.W. | So, B.J. | Bae, Y.C.
This paper describes a fatal case of pneumonia in a 14-day-old dog caused by extraintestinal pathogenic Escherichia coli (ExPEC). The necropsy showed that almost all of left lobes of the lungs had dark-red consolidation. A histopathology examination revealed moderate acute fibrino-hemorrhagic necrotizing pneumonia with intralesional bacterial colonies. Non-suppurative epicarditis, congestion in the liver, and necrosis in the white pulp of the spleen also were found. E. coli with cytotoxic necrotizing factor 1 and α-hemolysin was isolated from the lung. This case was confirmed to have fatal pneumonia caused by ExPEC that led to a systemic infection.
اظهر المزيد [+] اقل [-]Tentative diagnosis and monitoring using ultrasound in a cat with pansteatitis: a case report
2022
Kang, H.S. | Noh, D.J. | Lee, S.K. | Lee, K.J.
A 7-year-old Scottish Straight cat presented with hypersalivation and generalized hyperesthesia. The cat was provided tuna-based food for 2 to 3 weeks before clinical symptoms appeared. Abdominal ultrasonography showed a heterogeneous, hyperechoic mesentery with hypoechoic foci. Pansteatitis was tentatively diagnosed and the cat was treated with vitamin E, anti-inflammatory drugs, and dietary changes. The clinical signs and changes in mesenteric fat on serial ultrasonography resolved. After feeding tuna-based food again, the same clinical signs and mesenteric changes on ultrasound recurred, which recovered through the same treatment. This study suggests that ultrasonography can be useful for diagnosis and monitoring of feline pansteatitis.
اظهر المزيد [+] اقل [-]Effects of orthopedic postoperative rehabilitation treatments in dogs
2022
Kang, H.M. | Nahm, S.S.
Rehabilitation treatments after orthopedic surgery promote postoperative healing in humans. In veterinary medicine, there is increased interest in rehabilitation treatments because they are potentially beneficial to animals in the post-operation period. This study examined the effectiveness of rehabilitation treatment in dogs that underwent orthopedic surgeries, including femoral head & neck ostectomy (FHNO) and medial patellar luxation treatment (MPLT). The group that received the rehabilitation treatment after FHNO (1.88 weeks) showed a significantly shorter recovery length of 6.62 weeks compared to those that did not receive the treatment (8.50 weeks). The other group that received the rehabilitation treatment after MPLT (4.38 weeks) showed a significantly shorter recovery length of 5.01 weeks compared to those that did not receive the treatment (9.39 weeks). For the qualitative evaluation, the types and frequencies of rehabilitation treatments were monitored. The rehabilitation programs used frequently were heat therapy, laser therapy, passive range of motion, exercise therapy, and aquatic therapy. A standard rehabilitation program after hindlimb surgery was suggested based on the quantitative and qualitative investigation. The results add additional evidence that showed the beneficial effects of rehabilitation treatments in dogs.
اظهر المزيد [+] اقل [-]Non-epitheliotropic Cutaneous T-cell lymphoma in a cat: a case report
2022
Jeon, Y.S. | Bae, H.A. | Shin, S.W. | Cho, A.R. | Kim, Y.J. | Hwang, T.S. | Lee, H.C. | Hyun, J.E. | Cho, K.W. | Jung, D.I. | Kim, D.Y. | Yu, D.H.
Cutaneous lymphoma is rare in cats. An 11-year-old spayed female Persian cat presented with crust, ulceration, and multiple nodules on the shoulder and forelimb for 2 months. Computed tomography revealed a diffuse, irregularly margined lesion in the dorsal cutis extending from cervical to thoracic vertebrae. Cytological evaluation predominantly revealed large round cells with multilobulated nuclei and basophilic cytoplasm. Histopathological examination confirmed round CD3+/PAX5- cells packed in the dermis. Thus, the diagnosis of non-epitheliotropic cutaneous lymphoma with a diffuse large T-cell type was made. The disease progressed rapidly for the next 2 weeks, and the owner elected humane euthanasia.
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