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201.
Strohmeyer RA Morley PS Hyatt DR Dargatz DA Scorza AV Lappin MR 《Journal of the American Veterinary Medical Association》2006,228(4):537-542
OBJECTIVE: To evaluate bacterial and protozoal contamination of commercially available raw meat diets for dogs. DESIGN: Prospective longitudinal study. SAMPLE POPULATION: 240 samples from 20 raw meat diets for dogs (containing beef, lamb, chicken, or turkey), 24 samples from 2 dry dog foods, and 24 samples from 2 canned dog foods. PROCEDURE: Each product was purchased commercially on 4 dates approximately 2 months apart. Three samples from each product at each sampling period were evaluated via bacterial culture for non-type-specific Escherichia coli (NTSEC), Salmonella enterica, and Campylobacter spp. Antimicrobial susceptibility testing was performed on selected isolates. Polymerase chain reaction assays were used to detect DNA from Cryptosporidium spp, Neospora spp, and Toxoplasma spp in samples obtained in the third and fourth sampling periods. RESULTS: One hundred fifty-three of 288 (53%) samples were contaminated with NTSEC. Both raw and prepared foods contained NTSEC during at least 1 culture period. Salmonella enterica was recovered from 17 (5.9%) samples, all of which were raw meat products. Campylobacter spp was not isolated from any samples. In 91 of 288 (31.6%) samples, there was no gram-negative bacterial growth before enrichment and in 48 of 288 (16.7%) samples, there was no aerobic bacterial growth before enrichment. Susceptibility phenotypes were variable. Cryptosporidium spp DNA was detected in 3 samples. CONCLUSIONS AND CLINICAL RELEVANCE: Bacterial contamination is common in commercially available raw meat diets, suggesting that there is a risk of foodborne illness in dogs fed these diets as well possible risk for humans associated with the dogs or their environments. 相似文献
202.
Proverbio D Spada E Perego R Grieco V Lodi M Di Giancamillo M Ferro E 《Journal of the American Animal Hospital Association》2012,48(2):132-138
This report describes multiple endocrine neoplasia in a dog, which is a rare hereditary disorder characterized by the presence of two or more neoplasms of different endocrine tissues within a patient. A 14 yr old dog was evaluated for polyuria/polydipsia, polyphagia, and abdominal enlargement. Adrenal-dependent hyperadrenocorticism with concomitant left thyroid enlargement and a presumed abdominal metastatic lesion were diagnosed by an adrenocorticotropic hormone stimulation test, ultrasonography, and computed tomography. Trilostane therapy was initiated and resolved the clinical signs for 2 yr at which time the dog presented with left testicular enlargement. The dog was euthanized and was diagnosed with adrenocortical carcinoma, thyroid carcinoma, an abdominal mass compatible with a metastatic lymph node, and bilateral interstitial cell testicular adenomas. To the authors' knowledge, this is the first report to describe the concomitant association of these types of endocrine neoplasms in a dog. The concomitant presence of these neoplasms could represent a potential variant of multiple endocrine neoplasia; however, the presence of the interstitial cell testicular adenomas may have only been an incidental finding. If any of these tumors are diagnosed, veterinarians should perform a thorough clinical assessment to evaluate for the presence of additional endocrine neoplasms or hyperplasia. 相似文献
203.
Benjamin J. Schlegel Victoria J. Nowell Valeria R. Parreira Glenn Soltes John F. Prescott 《Canadian journal of veterinary research》2012,76(4):248-254
This study examined known or possible virulence-associated genes in type A Clostridium perfringens from cases of both bovine clostridial abomasitis (BCA) and jejunal hemorrhage syndrome (JHS) and compared these to isolates from calves that were healthy or had undifferentiated diarrheal illness. A real-time polymerase chain reaction (PCR) assay was used to genotype the 218 C. perfringens isolates. Isolates were sourced from healthy and diarrheic young and mature cattle (n = 191), from calves with confirmed or suspected BCA (n = 22), and from mature cattle with JHS (n = 5). Of 216 isolates (96%), 208 were positive for the cpa gene and 13% (29/218) were positive for atypical cpb2. Three of 8 (37.5%) confirmed BCA isolates, 2 of 13 (15.4%) suspected BCA isolates, and no JHS isolates tested positive for atypical cpb2. As all isolates were negative for cpb, cpb2, cpe, etx, netB, and tpeL, the results of the present study do not support a role for these genes in BCA or JHS. A subset of unique genes identified in 1 bovine clostridial abomasitis isolate (F262), for which a genome sequence is available, was searched for in 8 BCA isolates by PCR. None of the 10 genes was consistently present in all or even in a majority of BCA isolates. Many of these genes were also variably and inconsistently present in type A isolates from calves that did not have BCA. Although a virulence signature to aid in the diagnosis of BCA caused by C. perfringens type A was not identified, further work may discover a gene or group of genes that would constitute such a signature. 相似文献
204.
Irradiated brain tumors commonly progress at the primary site, generating interest in focal dose escalation. The aim of this retrospective observational study was to use biological optimization objectives for a modeling exercise with simultaneously‐integrated boost IMRT (SIB‐IMRT) to generate a dose‐escalated protocol with acceptable late radiation toxicity risk estimate and improve tumor control for brainstem tumors in dogs safely. We re‐planned 20 dog brainstem tumor datasets with SIB‐IMRT, prescribing 20 × 2.81 Gy to the gross tumor volume (GTV) and 20 × 2.5 Gy to the planning target volume. During the optimization process, we used biologically equivalent generalized equivalent uniform doses (gEUD) as planning aids. These were derived from human data, calculated to adhere to normal tissue complication probability (NTCP) ≤5%, and converted to the herein used fractionation schedule. We extracted the absolute organ at risk dose‐volume histograms to calculate NTCP of each individual plan. For planning optimization, gEUD(a = 4) = 39.8 Gy for brain and gEUD(a = 6.3) = 43.8 Gy for brainstem were applied. Mean brain NTCP was low with 0.43% (SD ±0.49%, range 0.01‐2.04%); mean brainstem NTCP was higher with 7.18% (SD ±4.29%, range 2.87‐20.72%). Nevertheless, NTCP of < 10% in brainstem was achievable in 80% (16/20) of dogs. Spearman's correlation between relative GTV and NTCP was high (ρ = 0.798, P < .001), emphasizing increased risk with relative size even with subvolume‐boost. Including biologically based gEUD values into optimization allowed estimating NTCP during the planning process. In conclusion, gEUD‐based SIB‐IMRT planning resulted in dose‐escalated treatment plans with acceptable risk estimate of NTCP < 10% in the majority of dogs with brainstem tumors. Risk was correlated with relative tumor size. 相似文献
205.
Analytic errors in Sysmex‐generated hematology results in blood from a dog with chronic lymphocytic leukemia
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Marilisa Novacco Valeria Martini Carmen Grande Stefano Comazzi 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2015,44(3):337-341
A blood sample from a 14‐year‐old dog was submitted to the veterinary diagnostic laboratory of the University of Milan for marked leukocytosis with atypical cells. A diagnosis of chronic T‐cell lymphocytic leukemia (CLL) was made based on blood smear evaluation and flow cytometric phenotyping. A CBC by Sysmex XT‐2000iV revealed a moderate normocytic normochromic anemia. Red blood cells counted by optic flow cytometry (RBC‐O) resulted in a higher value than using electrical impedance (RBC‐I). The relative reticulocyte count based on RNA content and size was 35.3%, while the manual reticulocyte count was < 1%. The WBC count of 1,562,680 cells/μL was accompanied by a flag. Manual counts for RBC and WBC using the Bürker chamber confirmed the Sysmex impedance results. Finally the manual PCV was lower than HCT by Sysmex. While Sysmex XT can differentiate between RBC and WBC by impedance, even in the face of extreme lymphocytosis due to CLL, RBC‐O can be affected by bias, resulting in falsely increased RBC and reticulocyte numbers. Overestimation of RBC‐O may be due to incorrect Sysmex classification of leukemic cells or their fragments as reticulocytes. This phenomenon is known as pseudoreticulocytosis and can lead to misinterpretation of regenerative anemia. On the other side PCV can be affected by bias in CLL due to the trapping of RBC in the buffy coat, resulting in a pink hue in the separation area. As HGB concentration is not affected by flow cytometric or other cell‐related artifacts it may represent the most reliable variable to assess the degree of anemia in cases of CLL. 相似文献
206.
In our ongoing search for new pharmacologically active leads from Solomon organisms, we have examined the sponge Theonella swinhoei. Herein we report the isolation and structure elucidation of swinholide A (1) and one new macrolide, swinholide J (2). Swinholide J is an unprecedented asymmetric 44-membered dilactone with an epoxide functionality in half of the molecule. The structural determination was based on extensive interpretation of high-field NMR spectra and HRESIMS data. Swinholide J displayed potent in vitro cytotoxicity against KB cells (human nasopharynx cancer) with an IC(50) value of 6 nM. 相似文献
207.
Valeria Terzi Nicola Pecchioni Primetta Faccioli Ladislav Kučera Antonio Michele Stanca 《Genetic Resources and Crop Evolution》2001,48(5):447-458
Fifteen Hordeum species and subspeciesbelonging to groups with different genomes were studied usingPCR-based markers to establish phylogenetic relationshipswithin the genus. Two hundred and seventeen RAPD and STS markers wereused to calculate genetic distances and construct phylogenetic trees.The phenetic analysis clearly separated the primary gene pool,represented by H. vulgaressp. vulgare, H.vulgare ssp. vulgare convar. vulgare f. agriochriton andH. vulgare ssp.spontaneum, from the secondary gene pool,represented by H. bulbosumand the tertiary gene pool, represented by American wild barleys andH. bogdanii. Data obtainedfrom PCO analysis are in complete agreement with taxonomicclassifications proposed previously, which were comparisons ofnumerous morphological, cytological and reproductivecharacters. 相似文献
208.
Valeria Terzi Caterina Morcia A. Michele Stanca Ladislav Kucera Clara Fares Pasquale Codianni Natale Di Fonzo Primetta Faccioli 《Genetic Resources and Crop Evolution》2007,54(7):1613-1621
In the last few years, the renewed interest for emmer wheat (Triticum dicoccon Schrank) in Italy has stimulated breeding programs for this crop releasing improved genotypes obtained not only by selection
from landraces, but even by crosses with durum wheat (Triticum durum Desf.) varieties. The purpose of this work has been to uncover the genetic make-up of some emmer × durum derivatives, specifically
by comparing the differences from their parents. Genetic diversity of advanced breeding lines and varieties derived from a
durum × emmer cross has been evaluated on the basis of AFLP and SSR markers in comparison with the corresponding emmer and
durum wheat parent for addressing the seminal question of how much ‘wild’ variation remains after selection for agronomic
type. 相似文献
209.
Evaluation of extracts and isolated fraction from Capparis spinosa L. buds as an antioxidant source 总被引:16,自引:0,他引:16
Germanò MP De Pasquale R D'Angelo V Catania S Silvari V Costa C 《Journal of agricultural and food chemistry》2002,50(5):1168-1171
The antioxidant activity of extracts from Capparis spinosa L. buds was evaluated using different in vitro tests: ascorbate/Fe(2+)-mediated lipid peroxidation of microsomes from rat liver; bleaching of 1,1-diphenyl-2-picryl-hydrazyl radical; and autoxidation of Fe(2+) ion in the presence of bathophenanthroline disulfonate. The methanolic extract showed strong activities in all of these in vitro tests. The amount of total phenols was determined in the methanolic extract. In addition, the level of rutin was calculated as 0.39% (w/w) by HPLC analysis. Our findings indicate the following: (a) the antioxidant efficiency of the methanolic extract may be attributed to its phenolic content; and (b) the antioxidant activity of the methanolic extract was maintained after removal of glucosinolates, confirming that these compounds do not interfere with the antioxidant properties of the extract. The results obtained from this study exalt the nutritional value of the flowering buds (capers) which are widely used as a source of flavor. 相似文献
210.
Reducing the level of infection of cereal heads caused by Fusarium and associated mycotoxin accumulation in grains is of a high priority in order to secure the yield, agronomic performance, and food and feed safety from field to table. Strategies to tackle the problem have been proposed at many levels, including greater knowledge of the biology of toxigenic fungi and of plant–pathogen interactions, monitoring activities which extend from the field to the end-products, pre-breeding, breeding and transgenesis to develop new resistant plant varieties, crop protection based on synthetic or natural molecules, biocontrol of fungal populations, the development and use of models that take into account the climatic conditions, and the adoption of technological protocols for reducing or inactivating mycotoxins. This review article highlights that the problem is very complex but that the scientific community continues to produce important knowledge and potential solutions. 相似文献