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851.
Morgan S. Schrock Abigail A. Zalenski Miranda M. Tallman Luke Kollin Anna Bratasz Griffin Weeks Margaret A. Miller Courtney N. Sweeney G. Elizabeth Pluhar Michael R. Olin William C. Kisseberth R. Timothy Bentley Peter J. Dickinson Daniel York Amy Webb Xu Wang Sarah Moore Monica Venere Matthew K. Summers 《Veterinary and comparative oncology》2023,21(3):492-502
High-grade glioma is an aggressive cancer that occurs naturally in pet dogs. Canine high-grade glioma (cHGG) is treated with radiation, chemotherapy or surgery, but has no curative treatment. Within the past eight years, there have been advances in our imaging and histopathology standards as well as genetic charactereization of cHGG. However, there are only three cHGG cell lines publicly available, all of which were derived from astrocytoma and established using methods involving expansion of tumour cells in vitro on plastic dishes. In order to provide more clinically relevant cell lines for studying cHGG in vitro, the goal of this study was to establish cHGG patient-derived lines, whereby cancer cells are expanded in vivo by injecting cells into immunocompromized laboratory mice. The cells are then harvested from mice and used for in vitro studies. This method is the standard in the human field and has been shown to minimize the acquisition of genetic alterations and gene expression changes from the original tumour. Through a multi-institutional collaboration, we describe our methods for establishing two novel cHGG patient-derived lines, Boo-HA and Mo-HO, from a high-grade astrocytoma and a high-grade oligodendroglioma, respectively. We compare our novel lines to G06-A, J3T-Bg, and SDT-3G (traditional cHGG cell lines) in terms of proliferation and sensitivity to radiation. We also perform whole genome sequencing and identify an NF1 truncating mutation in Mo-HO. We report the characterization and availability of these novel patient-derived lines for use by the veterinary community. 相似文献
852.
Bernstein JA Cook HE Gill AF Ryan KA Sirninger J 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2007,36(1):94-96
A 1-year-old male Foxhound/Walker Hound mix was presented to the small animal internal medicine service at Louisiana State University School of Veterinary Medicine with a 6-week history of progressive, multifocal, ulcerative and draining, well-circumscribed lesions in a generalized distribution. Prior to referral, a presumptive diagnosis was made of sterile pyogranulomatous disease; immunosuppressive therapy was instituted but resulted in clinical deterioration. At presentation, the dog had marked neutropenia (1100 neutrophils/microL), and a mild toxic left shift (400 bands/microL). Cytologic findings in the exudates from a draining skin lesion included high numbers of markedly degenerate neutrophils (about 95% of nucleated cells) as well as low numbers of macrophages, small mature lymphocytes, and eosinophils. Low numbers of intracellular (within neutrophils and macrophages) and extracellular, pleomorphic, cigar-to-ovoid shaped organisms ( approximately 3x9 microm) consistent with Sporothrix were observed. Histopathologic examination of a skin biopsy showed marked, chronic, active, ulcerative, pyogranulomatous dermatitis and panniculitis, with intralesional yeast consistent with Sporothrix sp. The etiologic agent was confirmed as Sporothrix schenckii by macerated tissue fungal culture. The patient was treated with itraconazole, enrofloxacin, and clindamycin, with clinical resolution occurring over a 3-month period. This case is a rare example of the cytologic diagnosis of Sporothrix schenckii in a canine patient. Diagnosis of canine sporotrichosis is often challenging and usually requires tissue culture, as infected dogs typically harbor very few organisms. The patient's prior immunosuppressive therapy likely contributed to higher numbers of organisms in exudates from the cutaneous lesions, facilitating cytologic diagnosis. 相似文献
853.
A 2-year-old Himalayan cat was presented for investigation of chronic, persistent, unilateral nasal discharge that was unresponsive to antibiotics. Unilateral choanal atresia was diagnosed on nasopharyngoscopy. Following surgical repair using the transnasal route and temporary stenting all clinical signs resolved. This is the first reported case of choanal atresia in a cat. It serves to alert practitioners to the occurrence of this unusual condition which should be included in the differential diagnoses of upper respiratory tract signs in young cats. 相似文献
854.
Amy Norvall Jose Guerrero Cota Nicola Pusterla Derek Cissell 《Veterinary radiology & ultrasound》2020,61(3):346-352
Equine temporomandibular joint (TMJ) diseases are increasingly recognized as a problem for the well‐being and performance of horses. Diagnosis is confounded by overlap of clinical signs associated with pathology of the oral cavity, poll, and cervical vertebrae. Arthrocentesis for intra‐articular analgesia, sampling of synovial fluid, and medication is needed for diagnostic and therapeutic purposes. Ultrasound features of the normal TMJ and a blind arthrocentesis technique have been described, but a systematic approach to ultrasound‐guided (USG) arthrocentesis has not been reported. Ultrasound guidance allows visualization of the TMJ that may prove beneficial in cases when pathology, abnormal anatomy, or clinician inexperience make blind arthrocentesis difficult. We hypothesized that USG arthrocentesis would result in fewer needle repositions than blind arthrocentesis. We also aimed to assess synovial fluid parameters for normal equine TMJs. A prospective randomized method comparison with crossover experimental design compared the number of needle positionings required for accurate injection of the TMJ using each technique. Arthrocentesis technique and operator experience were tested using cadavers and two operators. Injection success was confirmed using CT. The radiologist then applied both techniques in normal live horses. No statistically significant difference was noted between arthrocentesis techniques or operators (P > .05). No complications were observed in live horses following either technique. Synovial fluid parameters were largely within the normal range expected for other synovial joints. Either blind or USG arthrocentesis of the equine TMJ can be performed with minimal prior operator experience. Ultrasound‐guided arthrocentesis is an alternative method and can be considered in cases with altered anatomy. 相似文献
855.
856.
Gabriele Rossi Amy Richardson Hali Jamaludin Cristy Secombe 《Journal of veterinary diagnostic investigation》2021,33(1):59
Paraoxonase-1 (PON-1) activity is a new inflammatory and oxidative marker. Technical effects and biological factors could affect the accuracy of PON-1 activity measurement. We investigated the effects of storage at different temperatures, repeated freeze–thaw cycles, interferences from hemolytic, lipemic, and icteric samples, and seasonal effects on PON-1 activity in horses. We evaluated 2 substrates with an automated spectrophotometer. Ten equine serum samples were stored under different conditions. Although storage at room (21°C) or refrigeration (4°C) temperature induced a statistically significant decrease (p < 0.05) in PON-1 activity, this is not diagnostically relevant. PON-1 activity in frozen samples (−20°C) was stable for short-term storage; diagnostically significant (p < 0.01) fluctuations were observed after 1 mo. Four repeated freeze–thaw cycles were assessed, and all cycles affected PON-1 activity (p < 0.01); however, this was diagnostically significant only after the 4th cycle. Hemolysis induced an overestimation of PON-1 activity; lipemia and hyperbilirubinemia did not change PON-1 activity. Thirty-four horses were sampled monthly for 1 y, and PON-1 activity was higher in autumn (p < 0.05) and winter (p < 0.05) than in spring and summer. 相似文献
857.
Daniel L. Evans Victoria Janes-Bassett Pasquale Borrelli Claire Chenu Carla S. S. Ferreira Robert I. Griffiths Zahra Kalantari Saskia Keesstra Rattan Lal Panos Panagos David A. Robinson Samaneh Seifollahi-Aghmiuni Pete Smith Tammo S. Steenhuis Amy Thomas Saskia M. Visser 《European Journal of Soil Science》2022,73(1):e13145
858.
Over the last decade, researchers have developed a range of decision support systems (DSS) which seek to improve the evidence-base for decision-making in the forestry sector in Great Britain. Many are now integral to the systems of forest management and planning used. However, in some cases, levels of adoption have been lower than expected. This problem is neither unique to Great Britain nor to forestry, and increasingly it is being explained in terms of the quality of stakeholder engagement during DSS development and implementation. Thus, social research was undertaken to understand the factors affecting DSS uptake. The methods included an online survey completed by 81 members of the Institute of Chartered Foresters and Forestry Commission staff and 30 semi-structured interviews with stakeholders. Four sets of factors were seen to influence uptake: professional judgement and cultural resistance; communication and access; training, support and consolidation; and meeting user requirements. More generally, our conclusions highlight the need for a shift in the quality of interactions at the science–policy–practice interface: from knowledge-transfer (a unidirectional “bridging of gaps”) to knowledge-exchange (dialogue between collaborating partners) and knowledge-interaction (shared cultures and institutions). 相似文献
859.
Sui Hyang Kuit Louisa Shobhini Ponnampalam Philip S. Hammond Ving Ching Chong Amy Yee-Hui Then 《水产资源保护:海洋与淡水生态系统》2021,31(11):3120-3132
- The paucity of baseline data on coastal cetaceans due to a lack of research in developing countries frequently precludes assessment of their status and informed management actions for conservation.
- This study provides the first abundance estimates of Indo-Pacific humpback dolphins, Irrawaddy dolphins, and Indo-Pacific finless porpoises in the coastal waters of Matang, Peninsular Malaysia.
- Boat-based surveys covering 1,152 km2 of coastal waters with 4,108 km of survey effort were conducted between 2013 and 2016 to collect data for line transect analysis of Irrawaddy dolphins and finless porpoises. Photo-identification data of humpback dolphins were concurrently collected for mark–recapture analysis.
- Estimates of abundance from four sampling strata totalled 763 Irrawaddy dolphins (CV = 13%, 95% confidence interval (CI) [588, 990]) and 600 Indo-Pacific finless porpoises (CV = 27%, 95% CI [354, 1,016]).
- The annual abundance estimates of humpback dolphins ranged between 171 (95% CI [148, 208]) in 2014–2015 and 81 (95% CI [67, 98]) in 2015–2016, likely due to the presence of offshore individuals that moved in and out of the study area. The estuarine strata were inhabited by 68 (95% CI [63, 73]) inshore humpback dolphins in 2013–2014 to 87 (95% CI [78, 97]) dolphins in 2014–2015.
- As an International Union for Conservation of Nature important marine mammal area, the productive coastal waters of Matang are shown to support a high density of small coastal cetaceans, and the results serve as an important baseline for future studies to identify population trends for conservation management plans.
860.
Myron A Peck Lawrence J Buckley Linda M O'Bryan Edward J Davies & Amy E Lapolla 《Aquaculture Research》2004,35(10):992-996
In an effort to optimize the efficiency of high‐density incubation of Atlantic cod Gadus morhua and haddock Melanogrammus aeglefinus eggs, the per cent hatch of eggs treated with four disinfectants (3% hydrogen peroxide, 1% polyvinylpyrrolidone iodine, 0.1% sodium hypochlorite and a 0.005% antibiotic solution – penicillin/streptomycin) was compared in both species. The per cent hatch of eggs of each species was greatest after a 24 h treatment with the antibiotic solution. The hatching success of eggs treated within the different disinfectant treatments depended upon the embryonic developmental stage in both species. The sodium hypochlorite treatment had the lowest % coverage of colony growth after disinfected haddock eggs were plated onto sterile agar media, highest survival rates to the end of the embryonic period, but the lowest per cent hatch. 相似文献