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621.
For the Previcox (firocoxib, Merial) Experience Trial, practicing veterinarians across the United States were asked to enroll dogs diagnosed with osteoarthritis (OA). At an initial visit, owners of dogs deemed suitable for NSAID therapy were given Previcox and instructed to maintain a daily diary and to return 10 and 40 days after treatment began. Approximately 86% of the 1,002 enrolled dogs completed the study. The withdrawal rate associated with gastrointestinal side effects was low (2.9% of dogs), and no serious drug-related adverse events were reported. Investigators and Owners rated 93% and 91% of dogs, respectively, as improved, and 86% of owners rated their dogs "happier" or "more active" after treatment with firocoxib. The improvements observed following initiation of firocoxib therapy were independent of gender, breed, starting body weight, age, and prior NSAID use. These results support previous findings indicating that firocoxib is well tolerated and effective when used under field conditions.  相似文献   
622.
Presented is the case of an epiglottal fibrosarcoma in a dog. The location of the mass resulted in challenges in the delivery of adequate dose to the tumor, and herein we describe the treatment using an electronic brachytherapy source. The treatment consisted of four Gy fractions, twice daily for a total of 10 fractions (40 Gy total). Visual reevaluation two weeks after treatment supported adequate spatial dose delivery, and the patient was reportedly improved six weeks after treatment. We demonstrate that plesiotherapy using an electronic brachytherapy device is feasible and may be useful in the treatment of carefully selected veterinary tumors.  相似文献   
623.

Objective

To determine the anti-inflammatory efficacy of choline in vivo and in vitro and to investigate the anti-inflammatory mechanisms of choline.

Study design

Randomized, controlled studies.

Animals

In vivo trials used 16 Romney sheep. In vitro experiments utilized RAW 264.7 mouse macrophage cells.

Methods

Hypoxaemia induced in 16 sheep by intravenous (IV) injection of 50 μg kg–1 xylazine, an α-2 agonist, was measured in sheep at 0, 1 and 4 minutes using arterial blood gas analysis with and without 50 mg kg–1 IV choline chloride premedication. Cell culture studies used enzyme-linked immunosorbent assay to measure the release of tumour necrosis factor (TNF-α) from lipopolysaccharide (LPS) stimulated macrophages with and without choline chloride premedication. TNF-α release was compared to thalidomide suppressed and untreated cells.

Results

Choline premedication in sheep mitigated a reduction in arterial partial pressure of oxygen (PaO2) but did not prevent development of clinically significant hypoxaemia. Decrease in mean PaO2 of choline treated sheep was 6.36 kPa (47.7 mmHg) compared to 9.81 kPa (73.6 mmHg) in control sheep. In vitro studies demonstrate that choline administered concurrent with LPS activation did not significantly suppress TNF-α expression but that treatment of cells with choline 10 minutes prior to LPS activation did significantly suppress TNF-α expression. Choline pretreated cells expressed 23.99 ± 4.52 ng mg–1 TNF-α while LPS only control cells expressed 33.83 ± 3.20 ng mg–1.

Conclusions

Choline is able to prevent macrophage activation in vitro when administered prior to LPS activation and may reduce hypoxaemia in sheep developing pulmonary oedema after xylazine administration. This effect requires premedication with choline.

Clinical relevance

Pharmacological manipulation of autonomic inflammatory responses holds promise for the treatment of inflammation. However, the complex cellular mechanisms involved in this reflex means that an adequate therapy should approach multiple pathways and mechanisms of the inflammatory response.  相似文献   
624.
625.
Renal carcinomas (RC) are uncommonly encountered in feline medicine. Limited information regarding clinical presentation and postoperative outcomes is available. The purpose of this multi-institutional, retrospective study was to describe the presenting features and clinical outcomes of cats with RC undergoing nephrectomy. Thirty-six client-owned cats were included. Medical records from participating institutions were searched to identify cats that had a histopathologic diagnosis of RC and underwent nephrectomy from January 2001 to October 2021. The most common presenting complaints were weight loss (36.1%) and hyporexia (30.6%). Based on preoperative imaging and intraoperative findings, eight cats had suspected metastasis at the time of surgery (22.2%). Twenty-eight cats survived to discharge (77.8%). Median progression free interval (PFI) could not be determined, as only six cats developed suspected recurrence (16.7%) and seven cats developed suspected metastasis (19.4%). The all-cause median survival time (MST) was 203 days (95% confidence interval [CI]: 84, 1379 days). When cases that died prior to discharge were excluded, MST increased to 1217 days (95% CI: 127, 1641 days). One-year, two-year, and three-year survival rates were all 40.4%. Neither renal tumour histologic subtype nor the presence of preoperative azotemia, anaemia, erythrocytosis, haematuria, or suspected metastasis at diagnosis were found to influence survival. For cats surviving to discharge, prolonged survival times were possible. Further studies are necessary to elucidate other potential prognostic factors, the utility of postoperative adjuvant treatment, and to identify cats at-risk of mortality in the perioperative period.  相似文献   
626.
Palliative chemotherapy options for dogs with macroscopic non-osseous mesenchymal tumours are limited. The purpose of this study was to assess the response rate of these tumours to carboplatin chemotherapy. Medical records of 28 dogs treated with carboplatin for macroscopic mesenchymal neoplasia between 1990 and 2022 were retrospectively reviewed. Sixteen dogs with soft tissue sarcoma and 12 dogs with haemangiosarcoma were included. Responses observed included one complete response and three partial responses, for an overall response rate of 14.2% (4/28) and median time to progression of 42 days (range 21–259 days). Responses were only seen in patients with haemangiosarcoma, for a response rate of 33.3% (4/12) and median time to progression for responders of 103 days (range 39–252 days). Median time to progression for dogs with metastatic disease was similar to those with only local disease (distant median: 44 days; local median: 23 days, p = 0.56). Dogs with chemotherapy-naïve disease were compared to dogs having received previous chemotherapy treatment and had a median time to progression of 75 days and 40.5 days respectively (p = 0.13). Twenty-two dogs experienced 48 adverse events, with most being grade 1 or 2 (79%). Carboplatin was well tolerated, with variable macroscopic anti-tumour activity and short response duration. Carboplatin may be an acceptable rescue option for dogs with macroscopic haemangiosarcoma, especially those patients that cannot receive doxorubicin.  相似文献   
627.
Published radiotherapy results for spinal nephroblastomas in dogs are limited. In this retrospective longitudinal study (1/2007–1/2022), five dogs with a median age of 2.8 years received post-operative 3D conformal, conventional fractionated radiotherapy (CFRT) with 2–4 fields (parallel-opposed with or without two hinge-angle fields), for an incompletely resected nephroblastoma. Clinical findings prior to surgery included one or more of the following: pelvic limb paresis (5), faecal incontinence (2), flaccid tail (1), non-ambulatory (2) and deep pain loss (1). All masses were located between T11 and L3 and surgically removed via hemilaminectomy. Dogs received 45–50 Gray (Gy) in 18–20 fractions, and no dogs received chemotherapy post-radiation. At analysis, all dogs were deceased, with none lost to follow-up. The median overall survival (OS) from first treatment to death of any cause was 3.4 years (1234 days; 95% CI 68 days-upper limit not reached; range: 68–3607 days). The median planning target volume was 51.3 cc, with a median PTV dose of 51.4 Gy and median D98 = 48.3 Gy. Late complications or recurrence was difficult to fully determine in this small dataset; however, some degree of ataxia persisted throughout life in all dogs. This study provides preliminary evidence that post-operative radiotherapy may result in prolonged survival times dogs with spinal nephroblastomas.  相似文献   
628.
The cover image is based on the Research Article The novel pyridazine pyrazolecarboxamide insecticide dimpropyridaz inhibits chordotonal organ function upstream of TRPV channels by Christian Spalthoff et al., https://doi.org/10.1002/ps.7352

  相似文献   

629.
Studies were conducted to compare polyphenol oxidase (PPO) specific activities in various milling fractions of a variety of wheat cultivars and determine the levels of activities in a number of cultivars from different localities and harvesting seasons. Substrate specificities were also investigated. Bran was singled out as the richest source of PPO activity, which may also influence the activity in the other milling fractions that are known to have some proportion of bran content. We showed by gel electrophoresis and spectrophotometrically that the protein responsible for PPO activity apparently exists as a single isoform in bran and that the observed enzyme activity is likely to be a tyrosinase type, not a laccase or peroxidase. The specific activity was not significantly different between the reduction shorts and break shorts from the same cultivar, indicating a similar level of bran contamination in these fractions. Very low levels of PPO activity were recorded in the flour of all cultivars studied. Bran was used, therefore, to determine the varietal differences in the PPO activities in a number of cultivars from different localities and seasons of harvest. Results showed that the most significant determinant of PPO activity was the genotype, and this may be influenced by seasonality. We also determined that, apart from substrate preferences by the PPO enzyme, some phenolic acids actually inhibit PPO. Furthermore, we found that bran of some cultivars extracted with acidified methanol inhibited PPO activity substantially, whereas other extracts had less inhibitory properties. Thus, these unknown compounds in wheat may inhibit endogenous PPO activity.  相似文献   
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