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51.
Peters SM Yancy H Deaver C Jones YL Kenyon E Chiesa OA Esparza J Screven R Lancaster V Stubbs JT Yang M Wiesenfeld PL Myers MJ 《Veterinary immunology and immunopathology》2012,148(3-4):236-242
Non-steroidal anti-inflammatory drugs (NSAID) are a family of chemicals that function to reduce pain, fever, and inflammation, and they are commonly used in people and animals for this purpose. Currently there are no NSAIDs approved for the management of inflammation in swine due to a lack of validated animal models and suitable biomarkers to assess efficacy. A previous in vitro study examining biomarkers of inflammation identified fourteen genes that were significantly altered in response to Escherichia coli lipopolysaccharide (LPS)-induced inflammation. In the present study, five of those fourteen genes were tested in vivo to determine if the same effects observed in vitro were also observed in vivo. Plasma levels of prostaglandin E(2) (PGE(2)), an essential mediator of fever and inflammation, were also determined. Two groups of swine were stimulated with LPS with the second group also treated with flunixin meglumine. Blood was collected at 0, 1, 3, 6, 8, 24, and 48h post LPS-stimulation. The RNA was extracted from the blood and quantitative real-time-PCR (qRT-PCR) was utilized to determine the expression patterns of CD1, CD4, serum amyloid A2 (SAA2), Caspase 1, and monocyte chemoattractant protein 1 (MCP-1). The LPS-stimulated animals demonstrated a statistically significant alteration in expression of SAA2 and CD1 at 3h post-stimulation. Flunixin meglumine treated animals' demonstrated reduced expression of CD1 in comparison to the LPS-stimulated swine at 24 and 48h post LPS-stimulation. Flunixin meglumine treated animals exhibited reduced expression of SAA2 at 48h post-stimulation compared to LPS-stimulated swine. Swine treated with LPS demonstrated statistically significant increases in plasma PGE(2) at 1h post-stimulation. Swine treated with flunixin meglumine had no increase in plasma PGE(2) levels at any time. These results demonstrate that PGE(2) production, along with two out of five genes (SAA2 and CD1) have the potential to serve as early biomarkers of inflammation as well as indicators of NSAID efficacy. 相似文献
52.
53.
Wibke Himmelsbach Eduardo J. Treviño-Garza Humberto González-Rodríguez Marco A. González-Tagle Marco V. Gómez Meza Oscar A. Aguirre Calderón A. Eduardo Estrada Castillón Ralph Mitlöhner 《European Journal of Forest Research》2012,131(2):355-367
Water availability and salt excess are limiting factors in Mexican mixed pine-oak forest. In order to characterise the acclimatation
of native species to these stresses, leaf water (Ψw) and osmotic potentials (Ψs) of Juniperus flaccida, Pinus pseudostrobus and Quercus canbyi were measured under natural drought and non-drought conditions under two different aspects in the Sierra Madre Oriental.
Factorial ANOVA revealed significant differences in Ψw and Ψs between two aspects, species and sampling dates. In general, all species showed high predawn and low midday values that declined
progressively with increasing drought and soil–water loss. Seasonal and diurnal fluctuation of Ψw and Ψs were higher for J. flaccida and Q. canbyi than for P. pseudostrobus. Leaf Ψw and Ψs were mainly correlated with soil water content, while Ψs of P. pseudostrobus were hardly correlated with environmental variables. Thus, species have different strategies to withstand drought.
P. pseudostrobus was identified as a species with isohydric water status regulation, while J. flaccida and Q. canbyi presented water potential patterns typical for anisohydric species. The type of water status regulation may be a critical
factor for plant survival and mortality in the context of climate change. Nevertheless, for precise conclusions about the
advantages and disadvantages of each type, further long-term investigations are required. 相似文献
54.
Johanna Bernáldez Sergio A. Román-González Oscar Martínez Samanta Jiménez Oscar Vivas Isabel Arenas Gerardo Corzo Roberto Arreguín David E. García Lourival D. Possani Alexei Licea 《Marine drugs》2013,11(4):1188-1202
A novel peptide, RsXXIVA, was isolated from the venom duct of Conus regularis, a worm-hunting species collected in the Sea of Cortez, México. Its primary structure was determined by mass spectrometry and confirmed by automated Edman degradation. This conotoxin contains 40 amino acids and exhibits a novel arrangement of eight cysteine residues (C-C-C-C-CC-CC). Surprisingly, two loops of the novel peptide are highly identical to the amino acids sequence of ω-MVIIA. The total length and disulfide pairing of both peptides are quite different, although the two most important residues for the described function of ω-MVIIA (Lys2 and Tyr13) are also present in the peptide reported here. Electrophysiological analysis using superior cervical ganglion (SCG) neurons indicates that RsXXIVA inhibits CaV2.2 channel current in a dose-dependent manner with an EC50 of 2.8 μM, whose effect is partially reversed after washing. Furthermore, RsXXIVA was tested in hot-plate assays to measure the potential anti-nociceptive effect to an acute thermal stimulus, showing an analgesic effect in acute thermal pain at 30 and 45 min post-injection. Also, the toxin shows an anti-nociceptive effect in a formalin chronic pain test. However, the low affinity for CaV2.2 suggests that the primary target of the peptide could be different from that of ω-MVIIA. 相似文献
55.
Salgado-Roman M Botello-Alvarez E Rico-Martínez R Jiménez-Islas H Cárdenas-Manríquez M Navarrete-Bolaños JL 《Journal of agricultural and food chemistry》2008,56(21):10012-10018
Enzymatic treatments using noncommercial enzymes as a means to the improve the extraction of carotenoids and capsaicinoids from chili fruits are explored in this study. The results show that it is possible to obtain chili fruit powder with a higher concentration of both capsaicinoids and carotenoids than previously reported for similar processes. Furthermore, extraction yields above 96% for carotenoids and 85% for capsaicinoids as separate fractions can be achieved using a sequential and selective two-stage extraction. Evidence is presented demonstrating that the content and extraction yield depend directly on the extent of the enzymatic hydrolysis of chili cell walls, and higher yields are obtained when the sample is completely hydrolyzed. The enzymatic treatment described here is a promising alternative to current industrial practices, and it improves the extraction of carotenoids and capsaicinoids from chili fruits. 相似文献
56.
Masole Charity Ayuya Oscar Ingasia Moreki John Cassius 《Tropical animal health and production》2019,51(2):373-382
Tropical Animal Health and Production - This paper examines factors influencing the adoption of alternative response to Foot and Mouth Disease (FMD) among smallholder beef producers in the dry... 相似文献
57.
Samkange Alaster Kandiwa Erick Mushonga Borden Bishi Alec Muradzikwa Erdwin Madzingira Oscar 《Tropical animal health and production》2019,51(7):1829-1837
Tropical Animal Health and Production - A retrospective study from 2004 to 2017 investigated the effect of bull age, cow age and breed on conception rates, and calving intervals of beef cattle at... 相似文献
58.
Modifications to atrazine degradation pathways in a loamy soil after addition of organic amendments 总被引:4,自引:0,他引:4
The effects of two organic amendments, a municipal solid waste compost and a composted straw, on [U-ring-
]atrazine degradation pathways in a loamy soil (Grignon, Yvelines, France) were studied during laboratory incubations under controlled conditions. Three month conditionings were conducted under sterile or non-sterile conditions, with soil plus atrazine, organic amendment plus atrazine, or soil plus organic amendment. Then either an organic amendment or soil or atrazine was added, respectively, to these three treatments and incubated for an additional 3 months under non-sterile conditions. Both organic amendments modified the behaviour of atrazine in soil but via different processes. The addition of municipal compost increased atrazine sorption and decreased its availability for degradation by soil microorganisms. The effect of the composted straw was mainly related to its high enzymatic activity, which appeared to be responsible for the production of large amounts of hydroxyatrazine. This hydroxylation favoured the opening of the triazine ring and its subsequent mineralization in the soil. At the end of the incubations, less atrazine was mineralized in the presence of the two types of organic amendment, which both increased the formation of non-extractable residues of atrazine. The addition of municipal compost preserved larger amounts of extractable atrazine, while the addition of composted straw enhanced hydroxyatrazine production. In all cases, the greatest effects were found when atrazine was directly in contact with the organic amendment during conditioning. 相似文献
59.
Oscar Ramirez III DVM Richard K. Dodge MS Rodney L. Page DVM MS G. Sylvester Price DVM PhD Marlene L. Hauck DVM PhD Tracy A. Ladue DVM Felicia Nutter DVM Donald E. Thrall DVM PhD 《Veterinary radiology & ultrasound》1999,40(5):517-522
Ninety-five dogs with either a presumptive (n = 24) or biopsy confirmed diagnosis (n = 71) of osteosarcoma received palliative radiotherapy using 60Co photons. Parallel opposed beams were used with each dog receiving either 10 Gy on days 0, 7 and 21 (n = 58) or 8 Gy on days 0 and 7 (n = 37). The 8 Gy fractionation scheme was given with the intent of retreating upon relapse from pain relief. Only 9 of 37 (24%) dogs in the 8 Gy group returned for retreatment. Forty-seven of the 95 dogs (49%) received concurrent or sequential chemotherapy. Seventy of the 95 dogs (74%) experienced pain relief following treatment. In dogs experiencing pain relief the median duration of response was 73 days. Numerous clinical variables were evaluated as predictors of response. The only variable significantly related to achieving a response was the use of chemotherapy. The following variables were significantly related to the duration of response: extent of bone lysis, chemotherapy use, length of bone involved and tumor site (humerus). In a multivariate analysis (n = 73 dogs), after adjusting for chemotherapy use, extent of bone involvement (p = 0.01) and tumor site (p = 0.02) retained statistical significance, while degree of bone lysis did not (p = 0.11). No difference in response incidence or duration was found between 3 fractions of 10 Gy vs. 2 fractions of 8 Gy. Administration of a low initial dose with the intent of retreatment was not a successful strategy. 相似文献
60.
Rogelio GonzÁlez Armas Oscar Sosa-Nishizaki RenÉ Funes RodrÍguez & Victor AndrÉS Levy PÉrez 《Fisheries Oceanography》1999,8(3):238-242
We report the presence of striped marlin larvae in coastal waters of the mouth of the Gulf of California, collected during seven oceanographic cruises during 1990 to 1993. From 169 sampled stations, 30 produced a total of 68 larvae of 2.4–30.5 mm total length. Most of the larvae were about 3 mm, indicating a recent spawn. The sea surface temperature at the sampled stations ranged from 19.4°C to 32.0°C, but larvae were caught at stations with temperatures between 27.8°C and 31.5°C. These results clarify the existence of a spawning area of striped marlin in the eastern Pacific, located closer to the coast than previously believed, during several months of the year. 相似文献