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21.
The objective of this study was to evaluate the efficacy of Chinese herbs on Doxorubicin-induced focal and segmental glomerulosclerosis (FSGS) in rats. Twenty age-matched male Wistar rats were divided into two groups: group A (n = 10) given only water ad libitum served as the control group and group B (n = 10) was given Chinese herbs (40 ml/kg with drug concentration 1.75 g/ml) beginning at day zero. All rats were administered doxorubicin (7 mg/kg) intravenously. All the rats were placed in metabolic cages at day 0, 7, 14, 21, and 28, and daily proteinuria was measured. At day 28, the animals were killed by cervical dislocation, followed by immediate organ collection for histologic analysis of kidneys; blood was collected by tail vein and cardiac puncture (at day 28) for the measurement of serum albumin. Body weight (BW) and food intake were recorded. The rats in groups A and B demonstrated severe susceptibility to doxorubicin injection with the onset of proteinuria (80–100 mg/24h) at day 7. The rats in group B were partly resistant to doxorubicin nephropathy with decreasing proteinuria and increasing serum albumin compared with group A (p < 0.05). All 10 rats in group A developed at least 5% glomerulosclerosis with tubular casts at day 28. In contrast, the rats in group B developed less severe histologic renal disease. The difference in histologic scores between the two groups were significant at day 28 (12 in group B vs. 20 in group A, p = 0.002). Food intake of Group B animals progressively increased to reach 67–73% of those observed before the doxorubicin administration with 28–43% in Group A. After the 4-wk experimental period, BW in Group A decreased more significantly than that in Group B (?20 ± 3 and ?16 ± 1%, respectively, p = 0.035, paired T test). Chinese herbs seem to reduce proteinuria and attenuate renal histologic severity in rats with doxorubicin-induced FSGS and may offer an alternative to the treatment of FSGS.  相似文献   
22.
Carvacrol is a monoterpenic phenol produced by an abundant number of aromatic plants, including thyme and oregano. Presently, carvacrol is used in low concentrations as a food flavoring ingredient and preservative, as well as a fragrance ingredient in cosmetic formulations. In recent years, considerable research has been undertaken in an effort to establish the biological actions of carvacrol for its potential use in clinical applications. Results from in vitro and in vivo studies show that carvacrol possess a variety of biological and pharmacological properties including antioxidant, antibacterial, antifungal, anticancer, anti-inflammatory, hepatoprotective, spasmolytic, and vasorelaxant. The focus of this review is to evaluate the existing knowledge regarding the biological, pharmacological, and toxicological effects of carvacrol.  相似文献   
23.
23种中草药提取物对芒果炭疽病菌的抑制作用研究   总被引:12,自引:0,他引:12  
探讨了23种中草药提取物对芒果炭疽病菌的抑制作用,结果表明:丁香和黄芩2种中草药的提取物对芒果炭疽病菌具有很好的抑制作用,而夏枯草、紫草、艾叶和白茅根对炭疽病菌的生长具有促进作用。试验同时得出丁香提取物随浓度的降低,抑菌作用逐渐下降;而黄芩提取物浓度变化对抑菌作用没有明显影响。通过紫外一可见吸收光谱分析得知,丁香提取物中主要成分可能为丁香酚,黄芩提取物中主要成分可能为黄芩甙。  相似文献   
24.
To compare the difference in SPF values between a synthetic sunscreen and a sunscreen derived from Chinese herbs, by using optical and biological methods, we observed the effects of these sunscreens by photochemical reaction, sun protection factor (SPF) values, and UV absorption. The results showed that the synthetic sunscreen was more effective in UV absorption than the sunscreen derived from natural Chinese herbs. When they were tested biologically, it was found that the sunscreen derived from Chinese herbs was able to improve skin tonicity, as well as reduce the itching, photoerythema, squamation, burning, and reddening caused by the excessive UV radiation, while the synthetic sunscreen could not improve these conditions of the skin, and even induced some side-effects in the skin with photoerythema. By comparing the in vivo SPF values of the two types of sunscreen, they were found to be mainly similar. The results indicate that the SPF value was related to both a photo-reaction and a biological reaction. The sunscreen derived from natural Chinese herbs, although having low UV absorption, was able to exhibit the same SPF value as the synthetic sunscreen because of its biological effects.  相似文献   
25.
Medicinal herbs have a very important role in health protection and disease control, and have been used in health foods. Polycyclic aromatic hydrocarbons (PAHs) have carcinogenic, biological and mutagenic effects. In this paper, the content of 16?PAHs as representative contaminants in nine Chinese medicinal herbs, as additives for health foods, was investigated in order to ensure food safety from this source. A highly sensitive isotope dilution-gas chromatography-tandem mass spectrometry (ID-GC-MS/MS) method combined with gel permeation chromatography (GPC) and solid-phase extraction (SPE) was developed. Calibration curves showed good linearity for all PAHs (R 2?>?0.999), and the limit of quantification (LOQ) ranged from 0.42 to 2.7?µg?kg?1. Average recoveries for these compounds were in the range of 52.5–117%, 52.6–119% and 81.4–108% at the concentrations of 10, 50 and 250?µg?kg?1 with RSD of 1.8–15%, 0.9–15% and 1.0–15%, respectively. The proposed method was used for the analysis of nine Chinese medicinal herbs. Total levels of PAHs varied from 98.2?µg?kg?1 (cassia seed) to 2245?µg?kg?1 (eucommia bark). The highest level was found for phenanthrene (Phe) in liquorice root (631.3?µg?kg?1), indigowoad leaf (551.0?µg?kg?1), rose flower (435.2?µg?kg?1) and eucommia bark (432.3?µg?kg?1). The proposed method could provide a useful basis for safety monitoring of herbs and risk management for PAHs in the health food industry.  相似文献   
26.
A total of 60 Chinese medicinal herbs were examined for contamination of the emerging Fusarium mycotoxins enniatins (ENNs) A, A1, B, B1 and beauvericin (BEA). The herbs under study are commonly used in China as both medicines and food. The dried samples of herbs were randomly collected from traditional Chinese medicine stores in Zhejiang province, China. Sample preparation was achieved by methanol extraction, followed by a simple membrane filtration step; no tedious clean-ups were involved. ENNs A, A1, B, B1 and BEA were analysed by the recently developed stable isotope dilution assays, using liquid chromatography-tandem mass spectrometry (LC-MS/MS). With limits of detection ranging between 0.8 and 1.2 µg kg–1 for the analytes under study, 25% of all analysed samples were contaminated with at least one of the ENNs and BEA. BEA was the most frequently detected toxin with a 20% incidence in all samples. The percentages of ENN-positive samples were lower: each single ENN was detected in 6.7–11.7% of all samples. Considering the total amounts of the five mycotoxins in single samples, values between 2.5 and 751 µg kg–1 were found. The mean total amount in positive samples was 126 µg kg–1. Regarding ginger, the frequent occurrence of ENNs and BEA in dried ginger could be confirmed in samples from Germany. However, in fresh ginger root the toxins were not detectable. This is the first report on the presence of ENNs and BEA in Chinese medicinal herbs.  相似文献   
27.
ABSTRACT

Natural antioxidants in spices and herbs have attracted considerable attention as potential inhibitors against the formation of mutagenic heterocyclic amines (HCAs) in heat-processed meat. In this study, the inhibitory activity of four spices/herbs and their mixtures on HCAs formation in grilled beef were examined. A simplex centroid mixture design with four components comprising turmeric, curry leaf, torch ginger and lemon grass in 19 different proportions were applied on beef samples before grilling at 240 ºC for 10 min. The HCAs were extracted from the samples using solid phase extraction (SPE) method and analysed using Liquid chromatography mass spectrometry LC-MS/MS. All spices/herbs in single or mixture forms were found to reduce total HCA concentrations in marinated grilled beef ranging from 21.2% for beef marinated with curry leaf to 94.7% for the combination of turmeric and lemon grass (50:50 w/w). At the optimum marinade formula (turmeric: lemon grass 52.4%: 47.6%), concentration of 2-amino-3-methylimidazo[4,5-f]quinolone (IQ), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), Harman, Norharman and AαC were 2.2, 1.4, 0.5, 2.8 and 1.2 ng/g, respectively. The results of the mutagenic activity demonstrated that this optimised marinade formula significantly (p < 0.05) diminished mutagenicity of marinated grilled beef in bacterial Ames test.  相似文献   
28.
22种中药醇提物抑制蛋白质非酶糖基化作用的研究   总被引:4,自引:0,他引:4  
比较22种中药醇提物和氨基胍对体外蛋白质非酶糖基化反应的影响。分别将上述22种中药各5g,用乙醇提取、浓缩并定容至100ml,取1ml提取液与1ml磷酸缓冲液混合,90℃水浴40min,然后与乙二醛和牛血清白蛋白混合,反应混合液于37℃孵育15d,用荧光法测定糖基化产物的自发荧光值,计算不同中药醇提物对体外蛋白质非酶糖基化反应的抑制率。结果表明,在检测的浓度范围内,抑制率最高的是槐米(抑制率为96.7%),其次为大黄(抑制率为93.79%)和黄芩(抑制率为93.15%),它们都显著高于氨基胍的抑制率(89.56%)。槐米、大黄和黄芩的乙醇提取物可明显抑制体外蛋白质糖基化反应的结果预示它们在防治糖尿病血管并发症方面有应用潜力。  相似文献   
29.
探索大孔树脂分离技术对中药复方不同药物组合物理化学参数的影响。以黄连解毒汤为实验体系,测定AB—8大孔树脂分离前后该复方不同药物组合原液及醇洗脱液的pH值、电导率、浊度、粘度等指标。黄连解毒汤不同药物组合在AB—8大孔树脂分离前后的pH值、电导率、浊度、粘度等方面表现出不同的变化。大孔树脂分离技术可改变中药复方不同药物组合的物理化学参数。  相似文献   
30.
野菜矿物元素含量的测定   总被引:5,自引:0,他引:5  
测定了南京八卦洲乡同一种土壤长出的6种野菜和4种家菜中5种矿物元素的含量,并对其营养价值与保健价值进行了研究。  相似文献   
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