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31.
32.
MJ STUDDERT 《Australian veterinary journal》1994,71(10):351-351
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Adaptation of thermal threshold analgesiometry for NSAIDs in cats: effects of ketoprofen 总被引:1,自引:0,他引:1
Nonsteroidal anti‐inflammatory drugs (NSAIDs) are widely used to provide analgesia in clinical veterinary medicine, but there are few objective data evaluating this effect under controlled conditions in cats. Analgesia is more difficult to detect with acute analgesiometry after NSAIDs than after opioids. This investigation aimed to adapt the feline thermal analgesiometry method previously employed with opioids ( Dixon et al. 2002 ) for use with NSAIDs. Ketoprofen, a COX1 inhibitor licensed for cats was chosen. Six cats (2 neutered, four entire females, weighing 2.2–5.4 kg) were studied in two blinded randomized crossover trials each at least 2 weeks apart. Thermal thresholds (TT) were measured using the thermal threshold‐testing device previously developed for cats. A heater element and temperature sensor in a small probe were held at constant pressure against the cats' shaved thorax with an elasticized band. Skin temperature was recorded before each test, then the heater activated. When the cat responded by flinching, turning or jumping the heater was turned off and the temperature recorded. In the first study TT were measured following subcutaneous (SC) injection of ketoprofen (2 mg kg?1) or a similar volume of saline. In the second study, prior to TT, and under isoflurane restraint, a mild inflammatory focus was produced at the probe site by five SC injections of 5 mg kaolin in 0.1 mL saline at each corner and in the center of a 1.5‐cm square. Saline or ketoprofen as in the first study were injected at the same time. Three baseline temperatures were recorded before any injections were given. Thermal thresholds were measured at 1 and 2 hours and then two‐hourly for 24 hours. Data were analysed using anova . Baseline skin temperature increased (37.3 ± 0.5–38.1 ± 0.8 °C) 24 hours after saline injection in study 2 (p < 0.05) but did not change after any other treatment. Thermal thresholds decreased (40.0 ± 1.3 to 39.1 ± 0.4 °C) 16 hours after ketoprofen in study 1 (p < 0.05) and increased (41.6 ± 1.5–44.8 ± 6.1 °C) 16–24 hours after ketoprofen in study 2 (p < 0.05), with no significant changes after saline. No obvious increase in sensitivity to thermal stimulation after kaolin injection was detected although obvious inflammation was present for up to 36 hours and the cats responded to digital pressure at the treated site. The method detected some effects of a COX1 selective NSAID and may be suitable for future NSAID studies in cats. However, a pressure stimulus ( Dixon et al. 2000) may prove better than thermal, and it requires investigation. 相似文献
35.
MJ Siemieniuch E Jursza MP Kowalewski M Majewska DJ Skarzynski 《Reproduction in domestic animals》2013,48(1):72-78
Sex steroids in synergy with prostaglandins (PG) are involved in the regulation of cyclic ovarian function. In this study, we investigated the mRNA expression of three genes involved in arachidonic acid (AA) metabolism and hence PG production in domestic cats: PG‐endoperoxide synthase (PTGS2), PGF2α synthase (PGFS) and PGE2 synthase (PGES). Feline endometria (n = 16) were collected at oestrus and mid and late phases of pseudopregnancy. In addition, the effects of E2 and/or P4 on PG secretion and gene expression on endometrial explants were studied in an in vitro culture system. Expression levels of all examined genes were up‐regulated at the mid phase of pseudopregnancy. The effects of E2 and/or P4 treatment on both PG secretion and expression of the genes were observed after 12 h of culture. Expression of PGES was significantly up‐regulated by E2 plus P4 at oestrus and the mid phase of pseudopregnancy and was also up‐regulated by a single treatment with P4 at late pseudopregnancy (p < 0.05). Simultaneous incubation with E2 and P4 up‐regulated PTGS2 gene expression at oestrus and mid‐luteal phase (p < 0.05). Progesterone plus E2 significantly increased PGE2 secretion at oestrus and the mid phase of pseudopregnancy. However, treatment with E2 and/or P4 affected neither PGF2α secretion nor PGFS expression at any phase after 12 h of culture. The overall findings indicate that genes involved in PG synthesis are up‐regulated at the mid phase of pseudopregnancy. An increase in PGE2 secretion and up‐regulation of PGES and PTGS2 are the main responses of the endometrium to treatment with E2 and P4 at oestrus and the mid phase of pseudopregnancy in the cat. These data support the hypothesis that ovarian sex steroids via endometrial PGE2 are involved in endocrine homoeostasis, especially at oestrus and the mid, but not the late, phase of pseudopregnancy in cats. 相似文献
36.
MJ Siemieniuch 《Reproduction in domestic animals》2008,43(4):473-476
Apoptosis (programmed cell death) could be considered as a physiological process that takes part in a healthy organism, which helps to maintain organism homeostasis. The visible deterioration of semen quality and the number of germ cells is accompanied by a seasonal decrease of the reproductive activity in some species. This post-effect cascade is caused by apoptosis, which is the primary mechanism responsible for the elimination of germ cells during spermatogenesis. The aim of our study was to assess apoptotic changes in the epithelium germinativum in cat testes at different ages. One hundred and two pairs of testes were obtained from domestic cats aged between 4 months and 10 years. The paraffin-embedded tissue sections were labelled using the Oncogene and Calbiochem Research Products DNA Fragmentation Detection Kit (Cat# QIA21; Darmstadt, Germany), which allows the recognition of apoptotic nuclei in tissue sections with Fragment End Labelling (FragELTM ) of DNA. The activity of apoptotic processes in cat testes collected from the spring-summer period compared with the autumn-winter season revealed that, 59.42% and 51.51%, respectively, males testes were characterized by insignificant changes. The obtained data revealed a distinctive apoptotic changes in the young animal testes before spermatogenesis onset. An intensification of programmed death cells in the epithelium germinativum in the elder cats (between 3–6 and 6–10 years) was not observed. Apoptotic changes slightly intensified in cats aged between 12 and 36 months. 相似文献
37.
Accelerator mass spectrometer dating of an assemblage of fibrous and leather footwear from Arnold Research Cave in central Missouri documents a long sequence of shoe construction by prehistoric Midwestern peoples, beginning perhaps as early as 8300 calendar years before the present (cal years B.P.). An earlier fibrous sandal form dates from 8325 to 7675 cal years B.P., and later fibrous or leather slip-ons span the period from 5575 to 1070 cal years B.P. The assemblage adds to a growing picture of the highly varied nature of prehistoric footwear production in the United States throughout the Holocene. 相似文献
38.
Genesis and evolution of the 1997-98 El Nino 总被引:4,自引:0,他引:4
MJ McPhaden 《Science (New York, N.Y.)》1999,283(5404):950-954
The 1997-98 El Nino was, by some measures, the strongest on record, with major climatic impacts felt around the world. A newly completed tropical Pacific atmosphere-ocean observing system documented this El Nino from its rapid onset to its sudden demise in greater detail than was ever before possible. The unprecedented measurements challenge existing theories about El Nino-related climate swings and suggest why climate forecast models underpredicted the strength of the El Nino before its onset. 相似文献
39.
G. S. Pegg F. R. Giblin A. R. McTaggart G. P. Guymer H. Taylor K. B. Ireland R. G. Shivas S. Perry 《Plant pathology》2014,63(5):1005-1021
Puccinia psidii has long been considered a significant threat to Australian plant industries and ecosystems. In April 2010, P. psidii was detected for the first time in Australia on the central coast of New South Wales (NSW). The fungus spread rapidly along the east coast and in December 2010 was found in Queensland (Qld) followed by Victoria a year later. Puccinia psidii was initially restricted to the southeastern part of Qld but spread as far north as Mossman. In Qld, 48 species of Myrtaceae are considered highly or extremely susceptible to the disease. The impact of P. psidii on individual trees and shrubs has ranged from minor leaf spots, foliage, stem and branch dieback to reduced fecundity. Tree death, as a result of repeated infection, has been recorded for Rhodomyrtus psidioides. Rust infection has also been recorded on flower buds, flowers and fruits of 28 host species. Morphological and molecular characteristics were used to confirm the identification of P. psidii from a range of Myrtaceae in Qld and compared with isolates from NSW and overseas. A reconstructed phylogeny based on the LSU and SSU regions of rDNA did not resolve the familial placement of P. psidii, but indicated that it does not belong to the Pucciniaceae. Uredo rangelii was found to be con‐specific with all isolates of P. psidii in morphology, ITS and LSU sequence data, and host range. 相似文献
40.
Tim S. Bugni Cynthia D. Andjelic Ann R. Pole Prem Rai Chris M. Ireland Louis R. Barrows 《Fitoterapia》2009
A traditional preparation of Parmotrema saccatilobum (Taylor) Hale (Family: Parmeliaceae) is being considered for inclusion into the PNG national drug formulary by the Ministry of Health Taskforce on Traditional Medicines. The lichen preparation is traditionally used in the Milne Bay province of Papua New Guinea for analgesic and anti-inflammatory activities. A hexane extract of P. saccatilobum yielded the principle components atranorin and chloroatranorin. Atranorin and chloroatranorin were tested in a COX-1 and -2 enzyme inhibition assay, which showed that atranorin inhibited COX-1 in a dose dependent manner and suggests partial inhibition by atranorin and chloroatranorin of COX-2 and COX-1, respectively. 相似文献