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111.
Adipose triglyceride lipase (ATGL), a newly identified lipase, is a rate-limiting enzyme for triglyceride hydrolysis in adipocytes. The regulatory proteins involved in ATGL-mediated lipolysis in fat tissue are not fully identified and understood. The G(0)/G(1) switch gene 2 (G0S2) is an inhibitor of ATGL activity by interacting with ATGL through the hydrophobic domain of G0S2. Here, for the first time, we have cloned the coding sequence of G0S2 cDNA for the chicken, turkey, and quail. Sequence comparisons with mammals revealed that the avian G0S2 also have a conserved hydrophobic domain. Avian G0S2 is predominantly expressed in adipose tissues relative to other tested tissues. Within the adipose tissue, G0S2 is expressed 20-fold greater in the adipocyte than in the stromal-vascular (SV) fraction (P < 0.001). Expression of G0S2 mRNA gradually increased during differentiation of chicken adipocytes in culture (P < 0.05). However, there is G0S2 expression in embryonic adipose tissue, SV fraction, and primary preadipocytes before confluence that generally have an increased capacity of cell proliferation, which indicates it has an important role in adipocyte differentiation rather than proliferation. For a better understanding of how G0S2 responds to environmental stimuli, chickens were fasted for 24 h and then refed. Expression of G0S2 in adipose tissue was dramatically decreased (P < 0.05) in the chickens and quail after a 24-h fasting period, and increased to the control level after refeeding. In contrast to G0S2 expression, ATGL expression was induced (P < 0.05) after the 24-h fasting period and rapidly returned to the control level during the refeeding period. These data indicate that changes in lipolytic activities of adipose tissue in vivo can be regulated by G0S2 expression, as an inhibitor of ATGL.  相似文献   
112.
Serr J  Suh Y  Lee K 《Journal of animal science》2011,89(11):3490-3500
Adipose triglyceride lipase (ATGL) is the rate-limiting enzyme of lipolysis in chicken adipose tissue. Its regulation is not fully understood. Recent studies suggest ATGL may be regulated by physical protein-protein interactions. Comparative gene identification 58 (CGI-58) has been identified as an activator of ATGL in mice. The purpose of the current study was to clone and sequence the CGI-58 gene in avian species and to investigate its regulation during development, fasting, and refeeding. Here, we report the cloning and sequencing of the complete coding sequence of CGI-58 and the deduced AA sequences for the domestic chicken, turkey, and Coturnix quail. The CGI-58 protein is a 343-AA protein in the chicken and quail, and a 344-AA protein in the turkey. Sequence comparisons with the human and mouse show that the CGI-58 gene is highly conserved among avian and mammalian species, with complete identities at the predicted lipid-binding site. Cell fractionation of chicken fat cells and stromal-vascular cells revealed that CGI-58 is expressed primarily in mature adipocytes (P < 0.01). When compared in multiple organs and tissues, avian CGI-58 is expressed predominantly in the adipose tissue (P < 0.001), similar to ATGL. To understand CGI-58 expression during adipose tissue development, its mRNA expression was measured along with ATGL and stearoyl CoA desaturase (SCD-1) mRNA, an adipogenic marker, in embryos and adults. Messenger RNA expression of CGI-58 increased (P < 0.05) immediately after hatching, concurrent with peak ATGL expression. It is interesting that CGI-58 remained somewhat increased at posthatch d 11 and 33 as SCD-1 mRNA expression increased (P < 0.05). To evaluate the response of CGI-58 to nutritional status, chickens and quail were fasted for 24 h and subsequently refed. After the fasting period, CGI-58 mRNA was induced (P < 0.05) for both chickens and quail and was returned to control levels upon refeeding. The ATGL mRNA responded similarly, increasing dramatically after fasting and quickly decreasing with refeeding. The direct relationship between CGI-58 and ATGL mRNA expression indicates a role for CGI-58 in activating ATGL-mediated lipolysis in avian species.  相似文献   
113.
Policosanols (PCs) are a group of long‐chain alcohols that have been reported to have many beneficial physiological activities. In this study, the total content and composition of PCs in 15 rice (Oryza sativa L.) cultivars from Korea were characterized by gas chromatography–time‐of‐flight mass spectrometry. This method proved to be sufficiently precise and accurate with respect to the degree of endogenous biological variability found in the rice samples. Octacosanol (C28) and triacontanol (C30) were the major components of PCs in all cultivars. In addition, there were positive correlations among the determined PC contents. Given its high PC content, the Heughyangbyeo cultivar may appear to be a good candidate for future breeding programs.  相似文献   
114.
This study analyses the behaviour and mobility of major and some trace elements during the physical and chemical development of landslide-prone soil profiles in Limbe, SW Cameroon. The soils result from in situ weathering of Tertiary basaltic and picrobasaltic rocks. Textural and chemical characterisations, together with two mass balance models are applied to understand the mobility and redistribution of elements during the weathering of pyroclastic cones and lava flows. Weathering indices are used to estimate the extent of weathering. The chemical composition of the samples is evaluated by Inductively Coupled Plasma–Optical Emission Spectroscopy (ICP–OES) and their mineralogical composition by X-Ray Diffraction (XRD) analyses. It is observed that intensive weathering results in thick meta-stable soils in which significant loss of Ca, K, Mg, Na and Sr has taken place. There is a noticeable relative enrichment in all analysed trace elements (Ba, Zr, Y, Sc, V, Ni, and Co). Ti, Fe, Al, Mn, P and Ce tend to be leached in some horizons and concentrated in others. Zr, Ti, and Ce concentrations are greater in the soils than in the bedrock but show slight fluctuations in the soil and saprolites hence cannot be used as immobile elements for mass balance evaluations. Y increases progressively with advanced weathering. Major secondary mineral phases developed through weathering are a mixture of expanding (smectites) and non-expanding clays (kaolinite, halloysite and mica). The profiles show the presence of textural heterogeneities that can be exploited as slip surfaces. Data plotted in Si–Al–Fe diagram point out that the most advanced stage of weathering noted in these profiles is the kaolinisation stage.  相似文献   
115.
Here, percutaneous spinal cord injury (SCI) methods using a balloon catheter in adult rats are described. A balloon catheter was inserted into the epidural space through the lumbosacral junction and then inflated between T9-T10 for 10min under fluoroscopic guidance. Animals were divided into three groups with respect to inflation volume: 20 µL (n = 18), 50 µL (n = 18) and control (Fogarty catheter inserted but not inflated; n = 10). Neurological assessments were then made based on BBB score, magnetic resonance imaging and histopathology. Both inflation volumes produced complete paralysis. Gradual recovery of motor function occurred when 20 µL was used, but not after 50 µL was applied. In the 50 µL group, all gray and white matter was lost from the center of the lesion. In addition, supramaximal damage was noted, which likely prevented spontaneous recovery. This percutaneous spinal cord compression injury model is simple, rapid with high reproducibility and the potential to serve as a useful tool for investigation of pathophysiology and possible protective treatments of SCI in vivo.  相似文献   
116.
This study investigated the use of sprayed intraperitoneal bupivacaine to relieve postoperative pain behavior and biochemical stress response after laparoscopic ovariohysterectomy (LOVH) in dogs. Sixteen sexually intact female dogs were randomly assigned to two groups. The sprayed intraperitoneal bupivacaine (SIB) group received 4.4 mg/kg of sprayed intraperitoneal bupivacaine diluted to 0.25% with an equivalent volume of saline after pneumoperitoneum. The control group received 1.76 mL/kg of saline in a similar fashion. Both groups received preoperative periportal 5% bupivacaine (1 mL) before incision. Postoperative pain was measured using the short form of the Glasgow composite measures pain scale (CMPS-SF, 0-24). Serum cortisol and glucose concentrations were measured preoperatively and 0.5, 1, 2, 4, 6, 12, and 24h postoperatively. The SIB group had significantly lower CMPS-SF compared to the control group 1, 2, 4, 6, and 12h after the operation. Cortisol concentrations were significantly increased from preoperative concentrations in the control group at 0.5, 1, 2, and 4h post operation and at 0.5 and 1h post operation in the SIB group. No significant differences were seen in serum glucose within each group. This report suggests that the use of sprayed intraperitoneal bupivacaine can be used as part of a multimodal approach for pain management after LOVH in dogs.  相似文献   
117.
Here, we describe two dogs in which canine small intestinal submucosa (SIS) was implanted as a biomaterial scaffold during perineal herniorrhaphy. Both dogs had developed severe muscle weakness, unilaterally herniated rectal protrusions, and heart problems with potential anesthetic risks. Areas affected by the perineal hernia (PH) located between the internal obturator and external anal sphincter muscles were reconstructed with naïve canine SIS sheets. In 12 months, post-operative complications such as wound infections, sciatic paralysis, rectal prolapse, or recurrence of the hernia were not observed. Symptoms of defecatory tenesmus also improved. Neither case showed any signs of rejection or specific immune responses as determined by complete and differential cell counts. Our findings demonstrate that canine SIS can be used as a biomaterial scaffold for PH repair in dogs.  相似文献   
118.
119.
For innate immune defense, lower animals such as fish and amphibian are covered with skin mucus, which acts as both a mechanical and biochemical barrier. Although several mucus sources have been isolated and studied for their biochemical and immunological functions, the precise mechanism(s) of action remains unknown. In the present study, we additionally found the eel skin mucus (ESM) to be a promising candidate for use in anti-tumor therapy. Our results showed that the viability of K562 cells was decreased in a dose-dependent manner by treatment with the isolated ESM. The cleaved forms of caspase-9, caspase-3 and poly adenosine diphosphate-ribose polymerase were increased by ESM. The levels of Bax expression and released cytochrome C were also increased after treatment with ESM. Furthermore, during the ESM mediated-apoptosis, phosphorylation levels of ERK1/2 and p38 but not JNK were increased and cell viabilities of the co-treated cells with ESM and inhibitors of ERK 1/2 or p38 were also increased. In addition, treatment with lactose rescued the ESM-mediated decrease in cell viability, indicating lactose-containing glycans in the leukemia cells acted as a counterpart of the ESM for interaction. Taken together, these results suggest that ESM could induce mitochondria-mediated apoptosis through membrane interaction of the K562 human leukemia cells. To the best of our knowledge, this is the first observation that ESM has anti-tumor activity in human cells.  相似文献   
120.
Asiatic hybrid lilies, Lilium × elegans Thunb., ‘Red Carpet’ and ‘Sunray’ were used to investigate the effect of bulb vernalization at 2.5 °C on plant growth, flowering, and CO2 production (respiration), and to use the CO2 production pattern to monitor the time of flower bud initiation and development. Lily shoot emergence and flowering were accelerated when bulbs received 2.5 °C bulb vernalization; however, flowering was delayed when bulbs were stored at 20 °C before treatment at 2.5 °C; this indicated that bulbs were de-vernalized. The maximum CO2 level, and the minimum level, reached in 78 h in non-vernalized bulbs and in 110 h in 6 weeks of 2.5 °C (6 weeks/2.5 °C) treated bulbs, was increased as the 2.5 °C duration was increased; this indicated that CO2 level can be an useful parameter to measure the cold stimulus (i) accumulated in bulbs following bulb vernalization. The respiration rate higher than the predicted values of the best-fit curves derived from the quadratic equations was designated as Blip A and this was correlated to the time of flower bud initiation and development. Shoot elongation may follow the rise in carbon dioxide levels after reaching the minimum level. It is proposed that increased carbon dioxide levels higher than the predicted levels (Blip A), was correlated to the time of flower bud initiation and development. Measurement of carbon dioxide production upon receipt of bulbs may be a useful technique to provide important information for optimum vernalization treatments for bulbs that have accumulated different levels of low temperature stimulus after bulb vernalization.  相似文献   
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