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951.
Vail DM von Euler H Rusk AW Barber L Clifford C Elmslie R Fulton L Hirschberger J Klein M London C Martano M McNiel EA Morris JS Northrup N Phillips B Polton G Post G Rosenberg M Ruslander D Sahora A Siegel S Thamm D Westberg S Winter J Khanna C 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2012,26(3):598-607
Background
Effective treatments for dogs with advanced stage mast cell tumors (MCT) remain a pressing need. A micellar formulation of paclitaxel (paclitaxel [micellar]) has shown promise in early‐phase studies.Hypothesis/Objectives
The objective was to demonstrate greater activity for paclitaxel (micellar) compared with lomustine. The null hypothesis was μp = μL (ie, proportion of responders for the paclitaxel [micellar] and lomustine groups, respectively).Animals
Two hundred and fifty‐two dogs with advanced stage nonresectable grade 2 or 3 MCT.Methods
Prospective multicenter randomized double‐blind positive‐controlled clinical trial. The primary endpoint was confirmed overall response rate (CORR) at 14 weeks. A secondary endpoint, biologic observed response rate (BORR), also was calculated. Safety was assessed by the characterization and grading of adverse events (AE).Results
Overall CORR (7% versus 1%; P = .048) and BORR (23% versus 10%; P = .012) were greater for paclitaxel (micellar) compared with lomustine. Paclitaxel (micellar)‐treated dogs were 6.5 times more likely to have a confirmed response and 3.1 times more likely to experience a biologic observed response. The majority of AE with paclitaxel (micellar) were transient and clinically manageable. Twenty‐seven dogs (33%) receiving lomustine were discontinued because of hepatopathy compared with 3 dogs (2%) receiving paclitaxel (micellar) (P < .0001; odds ratio 26.7).Conclusions and Clinical Importance
Paclitaxel (micellar)'s activity and safety profile are superior to lomustine. The addition of an active and novel taxane to the veterinary armamentarium could fill a substantial need and, as its mechanism of action and AE profile do not overlap with currently available TKI, its availability could lead to effective combination protocols. 相似文献952.
Assarasakorn S Veir JK Hawley JR Brewer MM Morris AK Hill AE Lappin MR 《Research in veterinary science》2012,93(3):1213-1216
Flea infestations are common in Thailand, but little is known about the flea-borne infections. Fifty flea pools and 153 blood samples were collected from client-owned cats between June and August 2009 from veterinary hospitals in Bangkok, Thailand. Total DNA was extracted from all samples, and then assessed by conventional PCR assays. The prevalence rates of Bartonella spp. in blood and flea samples were 17% and 32%, respectively, with DNA of Bartonella henselae and Bartonella clarridgeiae being amplified most commonly. Bartonella koehlerae DNA was amplified for the first time in Thailand. Hemoplasma DNA was amplified from 23% and 34% of blood samples and flea pools, respectively, with 'Candidatus Mycoplasma haemominutum' and Mycoplasma haemofelis being detected most frequently. All samples were negative for Rickettsia felis. Prevalence rate of B. henselae DNA was increased 6.9 times in cats with flea infestation. Cats administered flea control products were 4.2 times less likely to be Bartonella-infected. 相似文献
953.
Western red cedar (WRC) is well known for its natural durability. However, the roles of all the extractives that may be associated with this durability are not fully understood. The literature primarily credits the thujaplicins, with a lesser role for the lignans; however, previous work has identified highly durable material with low thujaplicin content. To elucidate the relative importance of various extractives, the decay resistance of WRC stakes at four test sites was compared with data on the content of specific extractives to determine whether there was any detectable association. The concentration of plicatic acid, a lignan, was associated with the decay resistance of WRC lumber in ground contact. An unidentified, unquantified compound (B) appeared to be similarly associated with decay resistance. The thujaplicins were only weakly associated with the decay resistance of WRC in ground contact. 相似文献
954.
955.
The development of high‐quality wheat (Triticum aestivum L.) cultivars depends on a thorough understanding of the constituents of grain and their variation due to genetics and environment. Arabinoxylans (pentosans) are key constituents of wheat grain and have broad and far‐reaching influences on milling and baking quality. However, variation in arabinoxylans due to genotype and environment are not fully understood. In this study, 25 hard winter and 25 hard spring wheat commercial cultivars and advanced breeding lines developed from eight public and private breeding programs in the U.S. Pacific Northwest were analyzed for water‐extractable and total arabinoxylan contents (WE‐AX and total AX), and the proportion of total AX that was water‐extractable. Winter and spring genotypes were grown in three environments each. The results indicated that there were significant differences among both sets of hard wheat genotypes for WE‐AX, total AX, and proportion of total AX that was WE‐AX. The WE‐AX and total AX mean content ranges for the winter cultivars were 0.390–0.808 and 3.09–4.04%, respectively; and for the spring cultivars 0.476–0.919 and 3.94–4.70%, respectively. WE‐AX as a percentage of total AX was similar between the two genotype sets, 11.7–23.0%. Arabinoxylan fractions were generally not correlated with grain protein, test weight, and kernel hardness. The two highest correlations for winter wheats were between protein and total AX (r = –0.40) and test weight and percentage of total AX that were water‐extractable (r = 0.37) for winter wheats. Among spring wheats, single‐kernel characterization system hardness was negatively correlated with WE‐AX and proportion of total AX that was WE‐AX (r = –0.46 and –0.51, respectively). Although often significant, arabinoxylan fractions were usually not highly intercorrelated, indicating some independence of traits. Notable genotypes, being especially high or low for one or more arabinoxylan fraction and, thus, candidates for further genetic study and cross‐breeding, included Juniper, Eddy, and ORN980995 winter wheats, and Hollis, Alta Blanca, and WQL9HDALP spring wheats. Although the results indicate that arabinoxylan fractions of wheat grain can be highly influenced by environment, there is clear support for the existence of genetic differences, especially for WE‐AX and the proportion of total AX that is water‐extractable. As such, the manipulation of arabinoxylan content of wheat grain seems to be a reasonable breeding objective. 相似文献
956.
Cloning and phylogenetic analysis of polyphenol oxidase (PPO) genes in common wheat and its relatives would greatly advance
the understanding of molecular mechanisms of grain PPO activity. In the present study, six wheat relative species, including
T. urartu, T. boeoticum, T. monococcum, T. dicoccoides, T. durum and Ae. tauschii, were sampled to isolate new alleles at Ppo-A1 and Ppo-D1 loci corresponding to common wheat PPO genes, and seven new alleles were identified from these species, which were designated
as Ppo-A1c (from T. urartu), Ppo-A1d (T. boeoticum), Ppo-A1e (T. monococcum and T. durum), Ppo-A1f (T. dicoccoides), Ppo-A1g (T. durum), Ppo-D1c (Ae. tauschii) and Ppo-D1d (Ae. tauschii), respectively. Five out of the seven alleles detected in the wheat relatives contained an open reading frame (ORF) of 1,731
bp, encoding a polypeptide of 577 residues, which is the same as those of Ppo-A1 and Ppo-D1 genes in common wheat, whereas, the full-length ORF of the allele Ppo-A1g from T. durum was not obtained, and a 73-bp deletion occurred in the third exon of Ppo-D1d, an allele from Ae. tauschii, resulting in a shorter polypeptide of 466 amino acids. The 191-bp insertion in the first intron reported previously in common
wheat was also found in T. dicoccoides lines, implying that more than one tetraploid wheat lines may be involved in the origination of common wheat. Phylogenetic
trees were constructed using the genomic DNA sequences of the seven alleles, together with four from common wheat and four
partial PPO gene sequences deposited in GenBank. The genome tribe A was divided into two clusters, one of which contained
Ppo-A1d and Ppo-A1e, and the other included the remaining five alleles at Ppo-A1 locus. The alleles from different clusters showed high sequence divergences, indicated by dozens of SNPs and five to six
InDels. The genome tribe D comprised the alleles Ppo-D1a, Ppo-D1c, Ppo-D1d and Ppo-D1b, and the former three were clustered together, showing significant sequence divergence from Ppo-D1b. In addition, the relationships between these allelic variants and grain PPO activities were also discussed.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
957.
Shu DG Morris SC Han J Li Y Zhang XL Hua H Zhang ZF Liu JN Guo JF Yao Y Yasui K 《Science (New York, N.Y.)》2006,312(5774):731-734
Ediacaran assemblages immediately predate the Cambrian explosion of metazoans and should have played a crucial role in this radiation. Their wider relationships, however, have remained refractory and difficult to integrate with early metazoan phylogeny. Here, we describe a frondlike fossil, Stromatoveris (S. psygmoglena sp. nov.), from the Lower Cambrian Chengjiang Lagerst?tte (Yunnan, China) that is strikingly similar to Ediacaran vendobionts. The exquisite preservation reveals closely spaced branches, probably ciliated, that appear to represent precursors of the diagnostic comb rows of ctenophores. Therefore, this finding has important implications for the early evolution of this phylum and related diploblasts, some of which independently evolved a frondose habit. 相似文献
958.
Allen WR Wilsher S Morris L Crowhurst JS Hillyer MH Neal HN 《Equine veterinary journal》2006,38(5):454-459
REASONS FOR PERFORMING STUDY: Mares are occasionally encountered that consistently fail to conceive when inseminated, naturally or artificially, with fertile stallion semen in the absence of any identifiable pathology of either the structure or function of their reproductive tract. HYPOTHESIS: Temporary blockage of the oviducts by accumulations of naturally occurring oviducal masses may be preventing oviducal transport of the embryo to the uterus. METHODS: Mares, with known reproductive histories, that had exhibited inexplicable failure of conception were treated by laparoscopically guided administration of PGE2-laced triacetin gel directly onto the surface of their oviducts. RESULTS: Fifteen mares age 10-21 years that had exhibited inexplicable failure of conception during 1-4 years were treated, of which 14 (93%) conceived within the same or subsequent breeding season. CONCLUSIONS: The high success rate of this treatment supports the tentative diagnosis of oviducal obstruction in these mares and indicates that blockage of the mare's oviducts may occur in the form of a moveable accumulation of debris rather than from permanent fibrous adhesions resulting from salpingitis. POTENTIAL RELEVANCE: This laparoscopic application of PGE2 to the oviducts constitutes a sound and practical method of restoring fertility in mares suffering oviducal obstruction and further studies involving the procedure are warranted. 相似文献
959.
The medical records and histopathological sections of 29 dogs diagnosed with a unique eosinophilic dermatitis resembling Wells' syndrome were reviewed in an attempt to elucidate the pathogenesis of this syndrome. The medical records were reviewed for information on dermatological lesion appearance, systemic signs in other organ systems, clinical analyte abnormalities, and drug therapy. Histological sections of dogs with moderate to severe eosinophilic dermatitis without folliculitis and furunculosis were reviewed and evaluated for the presence of collagen flame figures. Three categories of patients were found. Category 1 consisted of 17 dogs treated for vomiting and/or diarrhoea (often haematochezia or haematemesis) prior (mean: 4.6 days) to the onset of skin lesions. Fourteen category 1 dogs had erythematous lesions (macules, papules or plaques) that were most pronounced on the abdomen. Sixteen of the 17 dogs received multiple classes of drugs, and 59% were hypoalbuminemic. Category 2 consisted of five dogs that had skin lesions and gastrointestinal signs at presentation and four of these dogs were hypoalbuminemic. Category 3 included seven dogs without enteric illness. A positive drug score was found in six category 1 dogs and one each from categories 2 and 3. Eighteen cases had eosinophilic dermatitis without flame figures, seven cases had early flame figures and four had well-developed flame figures. These changes did not correlate with the categories of clinical presentation. More than 50% of the dogs developed eosinophilic dermatitis following treatment for severe gastrointestinal disease. The authors propose that this represents a unique syndrome that may have causal drug association. 相似文献
960.
Companion animal staphylococcal isolate antibiograms were screened retrospectively to determine the frequency of methicillin-resistant (MR) infection by Staphylococcus aureus, Staphylococcus intermedius, and Staphylococcus schleiferi. Rates of MR were: S. aureus 35%, S. intermedius 17%, and S. schleiferi 40%. Frequency of isolation of methicillin-resistant S. aureus (MRSA) from dogs and cats was similar, whereas methicillin-resistant S. intermedius (MRSI) and methicillin-resistant S. schleiferi (MRSS) were significantly more common in dogs. MRSS was more commonly associated with superficial (skin and ear canal) infections, whereas MRSA was more commonly associated with deep infections. The MR strain resistance pattern to other classes of antibiotics was also investigated. MRSA was resistant to the most classes of antibiotics, followed by MRSI, while MRSS maintained the most favourable susceptibility profile. MR staphylococci may pose a significant risk to animal and public health. Therefore, to avoid selecting for resistant strains in cases of suspected staphylococcal infection, clinicians should consider culture and susceptibility testing early in the course of treatment. 相似文献