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51.
Intramuscular fat (IMF) in cattle is an important component of traits that influence meat quality. We measured carcass characteristics and gene expression in Korean steers to clarify the molecular mechanism(s) underlying IMF deposition in LM tissue by determining the correlation between IMF content and gene expression abundance and by developing models to predict IMF content using gene expression abundance. The deposition of IMF is determined by a balance between fat deposition and fat removal in the LM. We measured mRNA abundance of lipid metabolic genes including lipogenesis [acetyl CoA carboxylase (ACC), fatty acid synthase (FASN)], fatty lipid uptake [lipoprotein lipase (LPL), fatty acid translocase (CD36), fatty acid transport protein 1 (FATP1)], fatty acid esterification [glycerol-3-phosphate acyltransferase 1 (GPAT1), acylglycerol phosphate acyltransferase 1 (AGPAT1), diacylglycerol acyltransferase 1 (DGAT1), DGAT2], lipolysis [adipose triglyceride lipase (ATGL), hormone-sensitive lipase (HSL), monoglyceride lipase (MGL)], and fatty acid oxidation [carnitine palmitoyl transferase 1B, very long-chain acyl-CoA dehydrogenase (VLCAD), medium-chain acyl-CoA dehydrogenase (MCAD)] in the LM. The mRNA abundance of the GPAT1 gene showed the greatest correlation (r = 0.74; P < 0.001) with IMF content among 9 fat deposition genes. The gene expression abundance of other fat deposition genes including ACC, FASN, LPL, CD36, FATP1, AGPAT1, DGAT1, and DGAT2 also exhibited significant positive correlations (P < 0.05) with IMF content in the LM. Conversely, ATGL mRNA abundance showed the greatest negative correlation (r = -0.68; P < 0.001) with IMF content in the LM among 6 fat removal genes. The expression of other fat removal genes including MGL, VLCAD, and MCAD showed significant negative correlations (P < 0.05) with IMF content. Our findings show that the combined effects of increases in lipogenesis, fatty acid uptake, fatty acid esterification, and of decreases in lipolysis and fatty acid oxidation contribute to increasing IMF deposition in Korean steers. The multiple regression analysis revealed that the mRNA abundance of the GPAT1 gene in the LM was the first major variable predicting IMF content (54%) among 15 lipid metabolic genes. The second was mRNA abundance of ATGL (11%). In conclusion, these results suggest that GPAT1 and ATGL genes could be used as genetic markers to predict IMF deposition in the LM.  相似文献   
52.
This study was conducted to evaluate the effects of a combined mixture of phytogenic extracts (garlic and coriander) and probiotics on growth performance and immune responses in laying hens based on the results of in vitro studies to screen for immunomodulatory potency of each ingredient. Several parameters of immunomodulatory potency were estimated using lamina propria leucocytes (LPLs) isolated from rat intestinal mucosa tissue. Results show that the combined mixture enhanced LPLs proliferation, increased LPL‐mediated cytotoxicity against YAC‐1 tumour cells, and decreased lipopolysaccharide (LPS)‐induced cytokine production including tumour necrosis factor‐α (TNF‐α) and interferon‐γ (IFN‐γ) in LPLs. For in vivo study, laying hens (n = 50/each diet group) were fed with control diet, a diet containing antibiotics (0.01% per kg feed) or the combined mixture (0.02% per kg feed) for 21 days. The dietary combined mixture improved egg production (p < 0.05) but not growth performance and carcass traits. Interestingly, the patterns of suppressing plasma IFN‐γ productions during inflammation by LPS injection and decreasing caecal E. coli counts in the combined mixture group were comparable to those in the antibiotics group. Taken together, our results suggested that the 0.02% of combined mixture of phytogenic extracts and probiotics as ingredients has potential immunomodulatory effects in laying hens.  相似文献   
53.
 番薯(甘薯)黑斑病在國內现已蔓延十几个省份,造成的损失十分驚人,估計每年在貯藏期要毁掉薯塊二十億斤以上,春薯地区,育苗期普遍發生爛床,例如在河北省疫区調查結果,以前未發現黑斑病时候,每味能采8次苗以上,现在由于黑斑病为害的結果,只能采1-3次苗,苗床即已坏掉。  相似文献   
54.
An investigation of the location of Drechslera teres on barley (cv. Thibaut) seeds showed that, when artificial contamination was carried out at the time of flowering, all parts of the caryopsis. including the embryo, were infected by the two forms (f. teres and f. maculata ) of the pathogen. An assessment was made of the possible role of abiotic factors, including the effects of temperature and soil moisture, on the expression of the primary symptoms caused by the two forms of the pathogen. The most severe damage was observed in dry soils (pF 3-4) at temperatures off. 12°C. On young barley seedlings, the seed-borne inoculum caused coleoptile symptoms in the case of the form maculata , whereas the form teres induced mostly foliar symptoms. Foliar necroses may result from systemic invasion by the pathogen located in the seed.  相似文献   
55.
This study considers a carbon tax system as a policy tool for encouraging carbon sequestration through modification of management in existing forests and examines its welfare impacts and costs of the carbon sequestered. The simulated carbon tax leads to reduced harvest and increased carbon stock in the standing trees and understory biomass. Changes in the level of silvicultural investments vary by owner, depending on the nature of their initial inventory. In general investment under the tax is concentrated in regimes that establish faster growing plantations. Average rotation age increases, varying in extent across ownerships and site qualities. The carbon tax reduces both consumer and producer surpluses in regional timber markets. Producers are compensated by the carbon subsidies, except at low carbon tax levels. Not all rates of carbon tax will attract interest from private owners if participation is voluntary. Estimates of the marginal cost of sequestering carbon in western Oregon private forests are shown to be within the range of costs for projects considering afforestation alone in some eastern regions of the United States.  相似文献   
56.
ObjectiveTo evaluate the physiological variables, arterial blood gas values, induction of anesthesia quality, and recovery quality using the combination of butorphanol, midazolam and alfaxalone in dogs.AnimalsTen healthy adult Beagle dogs weighing 8.3 ± 3.1 kg.MethodsRectal temperature (T), pulse rate (PR), respiratory rate (fR), mean arterial pressure (MAP), and arterial blood gases were measured and recorded prior to intravenous (IV) administration of butorphanol, prior to administration of both midazolam and alfaxalone IV 10 minutes later, then every 5 minutes for 20 minutes. M-mode echocardiographic left ventricular (LV) indices were measured before and 5 minutes after administration of alfaxalone. Qualitative scores for induction of anesthesia and recovery were allocated, duration of anesthesia and recovery were calculated, and adverse events were recorded.ResultsScores for induction and recovery quality were excellent. No significant adverse events were observed. Mean ± SD time from induction to extubation and to standing (full recovery) was 29 ± 6 and 36 ± 8 minutes, respectively. There were statistically significant changes in PR, fR and MAP after drug administration. Transient hypercarbia developed after alfaxalone injection. The echocardiographic LV indices were reduced after alfaxalone injection, although those changes were not statistically significant.Conclusions and clinical relevanceThe combination of butorphanol, midazolam and alfaxalone provided excellent quality of induction of anesthesia and exerted minimal cardiopulmonary effects in healthy dogs.  相似文献   
57.
HER-2 and HER-3 are transmembrane receptor proteins that are considered to be important but poorly understood biomarkers in canine tumors. In this study, the expression and the localization of HER-2 and HER-3 were evaluated immunohistochemically in canine mammary tumors (n = 64; 12 benign, 52 malignant).HER-2 overexpression was identified in 2/12 (16.7%) benign and in 18/51 (35.3%) malignant cases. HER-3 was expressed in a non-nuclear localization in 11/12 (91.7%) benign and 18/52 (34.6%) malignant tumors. In contrast, HER-3 was expressed in the nucleus of neoplastic cells in 0/12 (0%) benign and 22/52 (42.3%) malignant tumors. Nuclear HER-3 expression was higher in neoplastic epithelial cells compared to myoepithelial cells, and positively correlated with high histological grade and lymphatic vessel invasion. These results suggest that nuclear HER-3 expression is significantly associated with tumor progression and metastasis and may serve as a useful prognostic biomarker in canine malignant mammary tumors.  相似文献   
58.
Stem cell based cell therapies offer significant potential for the field of regenerative medicine. Human amniotic fluid stem cells (hAFSCs) are an attractive source for lineage-specific differentiated stem cell therapy since they have properties that are able to differentiate into cells representing all three germ layers. To better understand the fate and location of implanted hAFSCs, a means to monitor cells in living subjects is essential. Here, we showed that differentiated cells, such as neurogenic, endothelial, and myogenic cells, derived from hAFSCs can be effectively labeled by the FITC-incorporated silica-coated nanoparticles, MNPs@SiO2 (FITC), although the labeling efficacy and cytotoxicity were distinct depending on the differentiated cell type. In addition, we observed that MNPs@SiO2-labeled cells provided sufficient signals for detection by optical and confocal microscope imaging when transplanted into the mice. These results suggest that the fluorescent dye incorporated MNPs@SiO2 are a useful tool for the cell labeling and in vivo tracking of differentiated cells derived from hAFSCs.  相似文献   
59.
The Korean 2008 self-sufficiency rate for grain was only 26.2%. Because of this, the quantity virtual water (VW) for crop product imports is much greater than that of other countries. International VW trade is especially important to Korea due to its dependency on foreign imports to maintain food security and to establish an agricultural water resource policy. Using international crop products trade statistics during 2003?C2007, this study analyzed the virtual water content (VWC) and international virtual water flow (VWF) of major crops. The national water savings and global water savings were also estimated. Major grain products, including 28 products made from 13 crops, were selected for the analysis, based on the net import and export of products totaling more than 10,000 tons. VWCs were computed for the selected major crop products using the VWC of the primary crop of Korea. International VWFs were estimated using the VWC of each crop products. The amount of imported VW was 16,804 and 226?M?m3 was exported, so that the net imported VW was 16,578?M?m3. VW import is concentrated in wheat, rice, maize (corn), and soybean crops. A small number of countries, including the USA, China, Brazil, etc., account for over 96% of the imported VW, indicating Korea??s heavy dependence on these countries. The average national water savings for Korea and the average global water savings according to crop were estimated using VW flow from international crop products trade during 2003?C2007. The estimate of national water savings was 23,870.3?M?m3. Three major crops, namely wheat, maize and soybean, account for 95.3% of this total VW saving. Global water savings from the VW trade amounted to 7,253.0?M?m3. Korea depends heavily on VW imports concentrated in specific crops and which are primarily imported from a particular set of countries. This indicates that Korea is vulnerable to disruptions in the international grain harvest such as those caused by natural disasters such as floods and drought. Any such disruption could easily become a critical issue for governmental planners who establish food and water supply policies for Korea.  相似文献   
60.
Synthetic agonists of TLR9 containing novel DNA structures and R'pG (wherein R=1-(2'-deoxy-beta-d-ribofuranosyl)-2-oxo-7-deaza-8-methyl-purine) motifs, referred to as immune modulatory oligonucleotides (IMOs), have been shown to stimulate T(H)-1-type-immune responses and potently reverse allergen-induced T(H)-2 responses to T(H)-1 responses in vitro and in vivo in mice. In order to investigate the immunomodulatory potential of IMOs in dogs, canine peripheral blood mononuclear cells (PBMC) from healthy dogs were stimulated with three different IMOs and a control IMO, alone or in combination with concanavalin A (ConA). Lipopolysaccharide (LPS) was used as a positive control for B lymphocyte activation. Carboxyfluorescein diacetate succinimidyl ester and phenotype staining was used to tag proliferating T and B lymphocytes (CD5(+) and CD21(+)) by flow cytometry. Real-time PCR and ELISA were processed to assay cytokine production of IFN-gamma, IL-10, TGF-beta, IL-6 and IL-10. Like LPS, IMOs alone induced neither proliferation of CD5(+) T cells nor CD21(+) B cells, but both LPS and IMO had the capacity to co-stimulate ConA and induced proliferation of B cells. In combination with ConA, one of the IMOs (IMO1) also induced proliferation of T cells. IMO1 also significantly enhanced the expression of IFN-gamma on the mRNA and protein level in canine PBMC, whereas expression of IL-10, TGF-beta and IL-4 mRNAs was not induced by any of the IMOs. These results indicate that in canine PBMC from healthy dogs, IMO1 was able to induce a T(H)-1 immune response including T- and B-cell proliferation.  相似文献   
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