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1.
This study was performed to examine the anti-fibrotic activity of HV-P411, an herbal mixture of seeds of Vitis vinifera, Schisandra chinensis and Taraxacum officinale extract, against carbon tetrachloride (CCl4)-induced liver fibrosis. Hepatic fibrosis was induced by intraperitoneal injection of CCl4 (0.5 ml/kg, twice weekly) for 8 weeks. Rats were treated orally with HV-P411 at 50, 100, 200, and 400 mg/kg once a day. After chronic exposure to CCl4, the levels of hydroxyproline were markedly increased; these were significantly reduced by HV-P411 at all dose levels. The level of serum aminotransferases and lipid peroxidation were increased after the CCl4 treatment, while reduced glutathione was decreased. These changes were attenuated by HV-P411. In addition, HV-P411 attenuated CCl4-induced raised serum concentration of transforming growth factor-β1, and the levels of matrix metalloprotease-2 and tissue inhibitor of metalloprotease-1 mRNAs. Our results suggest that HV-P411 may prevent liver fibrosis by modulating fibrogenesis and fibrolysis. 相似文献
2.
Trace amounts (0.004–0.55 ng) of beryllium (Be) in a dried bovine liver sample (20 mg) can be accurately determined by graphite-furnace atomic absorption spectrophotometry (GFAAS) after treating with microwave digestion (HNO3/H2O2) at 85 °C for 10 min and using acetylacetone as a chelating agent in the presence of an acetate buffer (pH 6.0). The method detection limit (MDL, 3σ) for Be was found to be 0.18 ng g−1 and the limit of quantification (LOQ, 10σ) was found to be 0.60 ng g−1; the calibration graph was linear up to 27 ng g−1. The Be contents measured in four liver and four muscle samples (BCR CRM-185R bovine liver, BCR CRM-384 pork muscle, and six samples collected in Kaohsiung, Taiwan, ROC) were between 2.3 and 4.7 ng g−1. Good spiked recoveries (96.0–103.0%) were obtained for these eight samples with a relative standard deviation (RSD, n = 3) ?3.0%. The method could be applied to measurements of Be in livers and muscles of poultry and livestock. 相似文献
3.
Abdul Qadir Shah Tasneem Gul Kazi Muhammad Balal Arain Muhammad Khan Jamali Hassan Imran Afridi Nusrat Jalbani Ghulam Abbas kandhro Jameel Ahmed Baig Raja Adil sarfraz Rehana ansari 《Food chemistry》2009
The purpose of this study was to estimate total arsenic concentration in different tissues (leg, breast, liver and heart) of broiler chicken by hydride generation atomic absorption spectrometry (HGAAS) and graphite furnace atomic absorption spectrometry (GFAAS), prior to microwave assisted acid digestion. The accuracy of the techniques was evaluated by using certified reference material DORM-2. The percentage recoveries of total As were observed as 100.6% and 99.4% for HGAAS and GFAAS, respectively. The precision of the techniques, expressed as relative standard deviation, was observed as 1.71% and 4.18% for HGAAS and GFAAS measurements, respectively. The limits of detection for HGAAS and GFAAS were 0.025 μg/g and 0.052 μg/g, respectively. The concentrations of total arsenic in different tissues of broiler chicken were found in the range of 2.19–5.28, 2.15–5.22, 2.97–7.17 and 2.68–6.36 μg/g for leg, breast, liver and heart tissues, respectively. At a mean level of chicken consumption (60 g/person/day), people may ingest in the range of 72.0–85.1 μg arsenic/person/day from chicken alone. 相似文献
4.
The antioxidant effect of two plant essential oils (sage and rosemary) and one synthetic antioxidant (BHT) on refrigerated stored porcine liver paté (4°C/90 days) was evaluated. Patés with no added antioxidants were used as controls. Liver patés were analysed for protein oxidation, modification of heme (HI) and non-heme iron (NHI) concentrations, and colour and texture characteristics at days 0, 30, 60 and 90 of refrigerated storage. The amount of carbonyls from protein oxidation significantly (p<0.05) increased during refrigerated storage, and this increase was significantly higher in the control patés than in their treated counterparts. Antioxidants successfully protected heme molecules from degradation and significantly inhibited the increase of NHI in refrigerated stored liver patés. Colour changes seemed not to be directly related to oxidative processes since patés with added antioxidants suffered greater colour modifications than the controls. The addition of rosemary essential oil significantly reduced hardness of liver patés. Sage and rosemary essential oils exhibited similar antioxidant properties to BHT denoting their suitability as alternatives to synthetic antioxidants. 相似文献
5.
Yung-Te Hou Hiroyuki IjimaShunichi Matsumoto Takafumi KuboTakayuki Takei Shinji SakaiKoei Kawakami 《Journal of Bioscience and Bioengineering》2010,110(2):208-216
A hepatocyte growth factor (HGF)/heparin-immobilized collagen system was used as a synthetic extracellular matrix for hepatocyte culture. The albumin synthesis, nucleus numbers and morphology of the hepatocytes were determined separately to evaluate the hepatocyte number and hepatocyte-specific function under this system. The benefits of the HGF/heparin-immobilized collagen system for hepatocyte culture were confirmed by three types of culture methods in vitro, namely 2D film cultures, 2D gel cultures and 3D gel cultures. In 2D collagen film cultures, hepatocytes exhibited the highest albumin synthesis (1.42 μg/well/day) in HGF/heparin-immobilized collagen films at 7 days of culture. Heparin inhibited hepatocyte adhesion while HGF promoted hepatocyte migration, and spheroid formation was easily detected in HGF/heparin-immobilized collagen films. In 2D collagen gel cultures, albumin synthesis of around 15 μg/well/day was detected and maintained for more than 18 days on HGF/heparin-immobilized collagen gels. Similar findings were obtained in 3D HGF/heparin-immobilized collagen gel cultures, which exhibited albumin synthesis of up to 30 μg/well/day. The albumin synthesis by hepatocytes was two-fold higher in 3D gel cultures compared with 2D gel cultures, and was maintained for over 2 weeks compared with 2D film cultures using the HGF/heparin-immobilized collagen system. Taken together, the HGF/heparin-immobilized collagen system was effective for albumin synthesis by hepatocytes in both 2D film cultures and 3D gel cultures, and therefore shows good potential for tissue engineering use. 相似文献
6.
Ishikawa M Sekine K Okamura A Zheng YW Ueno Y Koike N Tanaka J Taniguchi H 《Journal of Bioscience and Bioengineering》2011,111(6):711-718
Reconstitution of tissue architecture in vitro is important because it enables researchers to investigate the interactions and mutual relationships between cells and cellular signals involved in the three-dimensional (3D) construction of tissues. To date, in vitro methods for producing tissues with highly ordered structure and high levels of function have met with limited success although a variety of 3D culture systems have been investigated. In this study, we reconstituted functional hepatic tissue including mature hepatocyte and blood vessel-like structures accompanied with bile duct-like structures from E15.5 fetal liver cells, which contained more hepatic stem/progenitor cells comparing with neonatal liver cells. The culture was performed in a simulated microgravity environment produced by a rotating wall vessel (RWV) bioreactor. The hepatocytes in the reconstituted 3D tissue were found to be capable of producing albumin and storing glycogen. Additionally, bile canaliculi between hepatocytes, characteristics of adult hepatocyte in vivo were also formed. Apart from this, bile duct structure secreting mucin was shown to form complicated tubular branches. Furthermore, gene expression analysis by semi-quantitative RT-PCR revealed the elevated levels of mature hepatocyte markers as well as genes with the hepatic function. With RWV culture system, we could produce functionally reconstituted liver tissue and this might be useful in pharmaceutical industry including drug screening and testing and other applications such as an alternative approach to experimental animals. 相似文献
7.
The concentration of putrescine (PUT), spermidine (SPD) and spermine (SPM) was determined in chilled meat and kidneys of 18 rabbits and in liver of 12 animals 24 h after slaughter. Very low PUT concentrations were detected only in kidneys. Mean SPD levels were 2.2, 2.2, 61.7 and 32.7 mg kg− 1 in saddle, leg, liver and kidneys, respectively. The respective SPM concentrations were 14.7, 8.0, 115 and 88.4 mg kg− 1. SPD and SPM losses of about one third of the initial levels were apparent in saddles stored at − 18 °C for 8 months. Losses of both polyamines of about 15-20% of the initial concentrations were found in saddles stored aerobically at + 2 °C for up to 9 days. Stewing of saddles caused significant SPD and SPM losses of about 20-25%, while upon roasting and pan-roasting without oil a decrease of about 50% of the initial concentration was observed. 相似文献
8.
Heqing Shen Bernhard Henkelmann Walter Albert Rambeck Richard Mayer Ulrich Wehr Karl-Werner Schramm 《Food chemistry》2012
As one of the most important animal food sources, pigs are an important model in the assessment of human exposure to persistent organic pollutants (POPs). In the present study, the distribution of the administrated polychlorodibenzo-p-dioxin/furan (PCDD/F)–polychlorinated biphenyl (PCB) mixture and polybrominated diphenyl ethers (PBDEs) in the different tissues of pigs, including liver, lung, kidney, subcutaneous fat, mesentery and muscle, for understanding the physiologically based pollutant accumulation in these tissues and their edible safety was investigated. It was found that liver had a much higher potential to accumulate PCDD/Fs and dioxin-like pollutants like PCB-126 than the other tissues, but it did not specifically concentrate PBDE congeners as compared to the other tissues. The different PCDD/F congeners and PCB-126 followed a similar distribution pattern in the different tissues; also the different PBDE congeners have the similar pattern in these tissues. The liver’s higher concentrating potency for dioxin-like pollutants may result from its detoxification function, however, it can concentrate dioxin-like pollutants but not PBDEs may suggest that it is the toxicity but not lipophilic property of these POPs dominated their accumulation in liver tissues. Also the result suggested that liver is a high-risk edible tissue for dioxin-like pollutants. In conclusion, the present study suggested that physiologically based assessments are necessary for evaluating edible tissue safety in animal source foods. 相似文献
9.
根据毛发中微量元素的含量,应用逐步判别分析、主成分分析和逐步聚类分析等多变量统计分类技术,进行了肝癌辅助诊断的研究。所得结果令人满意,特别显示了用统计方法筛选出的几种元素在区分是否肝癌上起着显著作用。 相似文献
10.
P. KeanginP. Rattanadecho T. Wessapan 《International Communications in Heat and Mass Transfer》2011,38(6):757-766
Microwave ablation (MWA) is a process that uses the heat from microwave energy to kill cancer cells. MWA is able to focus radiation on the desired areas without damaging the surrounding tissue, entail a control of heating power for appropriate temperature distribution. Slot coaxial antennas are the most popular antennas in MWA because of their small dimensions and low cost to manufacture. To effectively treat liver cancer, these antennas can be used to produce a highly localized specific absorption rate (SAR) and temperature distribution pattern. In this work, the interstitial MWA in liver by single and double slot antennas is carried out. This paper focuses on the influence of antenna type on microwave power absorbed, SAR and temperature distribution. The results show that the maximum SAR and temperature appears in the liver tissue in case of single slot antenna which are higher than those of double slot antenna. However, no clear difference between these two microwave coaxial antenna (MCA) models has been shown, due to the low microwave power input from the MCA during MWA process. 相似文献