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991.
Mild, non-noxious, oscillating pinches to a rat's tail elicits hyperphagia. The present study examined whether tail-pinch (TP) would exert hyperalgesic and hyperactive effects in rats that also exhibit the overeating response. The first experiment assessed TP effects upon reactivity to electric shock as measured by flinch-jump thresholds. Significant decreases in jump thresholds were observed 0 and 15, but not 30, min following TP. This effect persisted regardless of whether food was present or absent during TP. The second experiment assessed TP effects upon reactivity to heat as measured by hot-plate latencies. In contrast to jump thresholds, the shortened hot-plate latencies observed following TP persisted into the recovery period. In examining TP effects upon activity levels (Experiment 3), it was found that animals display similar patterns of temporally-declining activity regardless of whether TP was administered or not. Finally, TP selectively decreased the analgesic responses to two different doses of morphine and two different cold-water swim temperatures (Experiment 4). The TP-induced reductions occurred when TP was administered either before or after the analgesic manipulation. These data are discussed in terms of the nociceptive selectivity of the TP effect, and its influences upon analgesic processes. 相似文献
992.
Janel K. Harris Simone A. French Robert W. Jeffery Paul G. McGovern Rena R. Wing 《Obesity (Silver Spring, Md.)》1994,2(4):307-313
Covariations in body mass index (BMI), physical activity, macronutrient intake, and the frequency of consumption of specific foods were examined among 82 men and 75 women participating in a behavioral weight loss program over a period of 18 months. Results of repeated measures analyses of covariance showed that BMI change was inversely related to change in physical activity and change in frequency of vegetable consumption. BMI change was positively related to change in calorie intake from fat and change in frequency of consumption of beef, hot dogs, and sweets. Change in fat calories predicted BMI change better than change in total calories. In addition, change in the frequency of consumption of specific foods accounted for a larger percentage of the variance in BMI change than did change in macronutrients (10.4% vs. 5.2%). No differences were found between predictors of weight loss vs. weight maintenance. 相似文献
993.
Makiko Horikawa Yosuke Kakiuchi Daiki Kashima Kenichiro Ogawa Masahiro Kawahara 《Biotechnology and bioengineering》2022,119(1):287-298
As protein–protein interactions (PPIs) are involved in many cellular events, development of mammalian cytosolic PPI detection systems is important for drug discovery as well as understanding biological phenomena. We have previously reported a c-kit-based PPI screening (KIPPIS) system, in which proteins of interest were fused with a receptor tyrosine kinase c-kit, leading to intracellular PPI-dependent cell growth. However, it has not been investigated whether PPI can be detected using other receptors. In this study, we employed a thrombopoietin receptor, which belongs to the Type I cytokine receptor family, to develop a thrombopoietin receptor-based PPI screening (THROPPIS) system. To improve the sensitivity of THROPPIS, we examined two strategies of (i) localization of the chimeric receptors on the cell membrane, and (ii) addition of a helper module to the chimeric receptors. Intriguingly, the nonlocalized chimeric receptor showed the best performance of THROPPIS. Furthermore, the addition of the helper module dramatically improved the detection sensitivity. In total, 5 peptide–domain interactions were detected successfully, demonstrating the versatility of THROPPIS. In addition, a peptide–domain interaction was detected even when insulin receptor or epidermal growth factor receptor was used as a signaling domain, demonstrating that this PPI detection system can be extended to other receptors. 相似文献
994.
Roginski Ana Cristina Zemniaçak Ângela Beatris Marschner Rafael Aguiar Wajner Simone Magagnin Ribeiro Rafael Teixeira Wajner Moacir Amaral Alexandre Umpierrez 《Journal of bioenergetics and biomembranes》2022,54(4):203-213
Journal of Bioenergetics and Biomembranes - Propionic acid (PA) predominantly accumulates in tissues and biological fluids of patients affected by propionic acidemia that may manifest chronic renal... 相似文献
995.
996.
Santos-Jiménez José Leonardo de Barros Montebianco Caroline Vidal Andreza Henrique G. Ribeiro Simone Barreto-Bergter Eliana Vaslin Maite Freitas Silva 《BioControl》2022,67(1):75-87
BioControl - Passion fruit woodiness disease is responsible for severe losses in passion fruit production around the world. The disease is caused by Cowpea aphid-borne mosaic virus (CABMV), an... 相似文献
997.
Annalisa Reale Simone Brogi Alessia Chelini Marco Paolino Angela Di Capua Germano Giuliani Andrea Cappelli Gianluca Giorgi Giulia Chemi Alessandro Grillo Massimo Valoti Lidia Sautebin Antonietta Rossi Simona Pace Concettina La Motta Lorenzo Di Cesare Mannelli Elena Lucarini Carla Ghelardini Maurizio Anzini 《Bioorganic & medicinal chemistry》2019,27(19):115045
A novel series of 1,5-diarylpyrrol-3-sulfur derivatives (10–12) was synthesized and characterized by NMR and mass spectroscopy and x-ray diffraction. The biological activity of these compounds was evaluated in in vitro and in vivo tests to assess their COX-2 inhibitory activity along with anti-inflammatory and antinociceptive effect.Results showed that the bioisosteric transformation of previously reported alkoxyethyl ethers (9a-c) into the corresponding alkyl thioethers (10a-c) still leads to selective and active compounds being the COX-2 inhibitory activity for most of them in the low nanomolar range. The oxidation products of 10a,b were also investigated and both couple of sulfoxides (11a,b) and sulfones (12a,b) showed an appreciable COX-2 inhibitory activity. Molecular modeling studies were performed to investigate the binding mode of the representative compounds 10b, 11b, and 12b into COX-2 enzyme and to explore the potential site of metabolism of 10a and 10b due to the different in vivo efficacy. Among the developed compounds, compound 10b showed a significant in vivo anti-inflammatory and antinociceptive activity paving the way to develop novel anti-inflammatory drugs. 相似文献
998.
999.
In vitro differentiation of male mouse embryonic stem cells into both presumptive sperm cells and oocytes 总被引:1,自引:0,他引:1
Kerkis A Fonseca SA Serafim RC Lavagnolli TM Abdelmassih S Abdelmassih R Kerkis I 《Cloning and stem cells》2007,9(4):535-548
Pioneer work in male mouse embryonic stem (ES) cells differentiation into germ cells (GC) showed generations of male or female gametes in separate experiments, using genetically manipulated or preselected ES cells. In an attempt to produce both types of gametes from male mouse ES cells without any genetic manipulation or preselection, we induce the differentiation by retinoic acid (RA) within nonadherent embryoid bodies (EB). It seems that gamete-like cell formation occurs in the correct manner based on the expression of early and late GC-specific genes such as Oct-4, Mvh, Stella, Dazl, Piwil 2, Pdrd 1, Rex 14, Rnf 17, Bmp8b, Acrosin, Stra-8, Haprin, LH-R, Gdf9, Zp3, Zp2, Sycp1, and Sycp3. Immunofluorescence analysis of morphologically well-formed GC and presumptive gametes showed positive labeling for SSEA1, Oct-4, EMA-1, FE-J1, Dazl, Fragilis, Mvh, Acrosin, and acetylated alpha-tubulin. Conventional cytogenetic and FISH analysis indicated a chromosome reduction in ES-derived GC. Our data suggest that ES cells with XY chromosomes can produce under the same experimental conditions both types of presumptive gametes, and this production depends on their positional and temporal information within the EB context. 相似文献
1000.
Sigurdson CJ Nilsson KP Hornemann S Manco G Polymenidou M Schwarz P Leclerc M Hammarström P Wüthrich K Aguzzi A 《Nature methods》2007,4(12):1023-1030
The occurrence of multiple strains of prions may reflect conformational variability of PrP(Sc), a disease-associated, aggregated variant of the cellular prion protein, PrP(C). Here we used luminescent conjugated polymers (LCPs), which emit conformation-dependent fluorescence spectra, for characterizing prion strains. LCP reactivity and emission spectra of brain sections discriminated among four immunohistochemically indistinguishable, serially mouse-passaged prion strains derived from sheep scrapie, chronic wasting disease (CWD), bovine spongiform encephalopathy (BSE), and mouse-adapted Rocky Mountain Laboratory scrapie prions. Furthermore, using LCPs we differentiated between field isolates of BSE and bovine amyloidotic spongiform encephalopathy, and identified noncongophilic deposits in prion-infected deer and sheep. We found that fibrils with distinct morphologies generated from chemically identical recombinant PrP yielded unique LCP spectra, suggesting that spectral characteristic differences resulted from distinct supramolecular PrP structures. LCPs may help to detect structural differences among discrete protein aggregates and to link protein conformational features with disease phenotypes. 相似文献