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1.
Context: Eurycoma longifolia Jack (Simaroubaceae) commonly known as Tongkat Ali is one of the most important plants in Malaysia. The plant extracts (particularly roots) are widely used for the treatment of cough and fever besides having antimalarial, antidiabetic, anticancer and aphrodisiac activities.

Objectives: This study assesses the extent of adulteration of E. longifolia herbal medicinal products (HMPs) using DNA barcoding validated by HPLC analysis.

Materials and methods: Chloroplastic rbcL and nuclear ITS2 barcode regions were used in the present study. The sequences generated from E. longifolia HMPs were compared to sequences in the GenBank using MEGABLAST to verify their taxonomic identity. These results were verified by neighbor-joining tree analysis in which branches of unknown specimen are compared to the reference sequences established from this study and other retrieved from the GenBank. The HMPs were also analysed using HPLC analysis for the presence of eurycomanone bioactive marker.

Results: Identification using DNA barcoding revealed that 37% of the tested HMPs were authentic while 27% were adulterated with the ITS2 barcode region proven to be the ideal marker. The validation of the authenticity using HPLC analysis showed a situation in which a species which was identified as authentic was found not to contain the expected chemical compound.

Discussion and conclusions: DNA barcoding should be used as the first screening step for testing of HMPs raw materials. However, integration of DNA barcoding with HPLC analysis will help to provide detailed knowledge about the safety and efficacy of the HMPs.  相似文献   

2.

Background

Several methods have been developed to determine a person’s physical activity level. However, there is limited evidence in determining whether someone is physically active or not. This study aims to determine the level of physical activity and to compare the usage of short version International Physical Activity Questionnaire (IPAQ-SF) and pedometer among overweight and obese women who were involved in the My Body is Fit and Fabulous at home (MyBFF@home) study.

Methods

Baseline and sixth month data from the MyBFF@home study were used for this purpose. A total of 169 of overweight and obese respondents answered the IPAQ-SF and were asked to use a pedometer for 7 days. Data from IPAQ-SF were categorised as inactive and active while data from pedometer were categorised as insufficiently active and sufficiently active by standard classification. Data on sociodemographic and anthropometry were also obtained. Cohen’s kappa was applied to measure the agreement of IPAQ-SF and pedometer in determining the physical activity level. Pre-post cross tabulation table was created to evaluate the changes in physical activity over 6 months.

Results

From 169 available respondents, 167 (98.8%) completed the IPAQ-SF and 107 (63.3%) utilised the pedometer. A total of 102 (61.1%) respondents were categorised as active from the IPAQ-SF. Meanwhile, only 9 (8.4%) respondents were categorised as sufficiently active via pedometer. Cohen’s κ found there was a poor agreement between the two methods, κ?=?0.055, p?>?0.05. After sixth months, there was +?9.4% increment in respondents who were active when assessed by IPAQ-SF but ??1.3% reductions for respondents being sufficiently active when assessed by pedometer. McNemar’s test determined that there was no significant difference in the proportion of inactive and active respondents by IPAQ-SF or sufficiently active and insufficiently active by pedometer from the baseline and sixth month of intervention.

Conclusion

The IPAQ-SF and pedometer were both able to measure physical activity. However, poor agreement between these two methods were observed among overweight and obese women.
  相似文献   
3.
骨髓干细胞分化为肝细胞的多种移植途径   总被引:3,自引:0,他引:3  
近年来许多研究证实,人类和啮齿类动物的骨髓细胞可分化为多种细胞类型,包括骨骼肌细胞、心肌细胞、神经细胞和肝细胞等,这些骨髓干细胞的可塑性研究,为肝细胞移植提供了新的供体来源.骨髓干细胞替代肝细胞进行移植具有来源丰富,费用相对低廉,对患者损伤小等优点,且自体骨髓干细胞移植可以完全避免移植排斥反应,同时,骨髓干细胞只有 5-15 μm,移植后不会发生栓塞等并发症.因此骨髓干细胞移植在治疗肝病以及解决供体肝脏来源短缺方面具有广泛的应用前景.本文就骨髓干细胞的移植途径做一综述.  相似文献   
4.
5.
BACKGROUND: P-glycoprotein (PgP) is the most extensively studied ATP-binding cassette (ABC) coded by MDR1 gene. To date, 29 single nucleotide polymorphisms (SNPs) have been identified; but only SNP C3435T has been correlated with intestinal PgP expression levels and shown to influence the absorption of orally taken drugs that are PgP substrates. Individuals homozygous for the T allele have more than fourfold lower PgP expression compared with C/C individuals. We developed a one step primer based allele specific PCR method to detect SNP at C3435T to investigate the distribution of this genotype in the local population. METHOD: DNA was extracted from 5 mL of whole blood using standard salting-out method. Primers were designed specific to 3' end which amplify the variants of C3435T. The method was validated by direct DNA sequencing. Seven hundred and sixty-three healthy blood donors comprising of three major ethnic groups in Malaysia were recruited and DNA subjected to genotyping of C3435T using this method. RESULT: The method was found to be robust and reproducible in detecting SNP of C3435T. Interethnic variations in genotype and allele frequency were observed in PgP among the ethnic groups. In comparison to both the Caucasians and the other Asian countries, the Malay and Chinese showed a higher frequency of allele C (50-60%); while the Indian exhibits a lower frequency (40%), similar to other Indian populations. DISCUSSION AND CONCLUSION: Using a new simple method to investigate the distribution of C3435T, we found that the allele frequency of MDR1 showed variablity between the different ethnic groups within the Malaysian population.  相似文献   
6.
目的:观察对胃溃疡复发有较好疗效的健胃愈疡颗粒对溃疡黏膜乳腺癌相关肽和血小板活化因子表达的影响,分析其可能的作用机制。方法:实验于2005-07/2006-07在湘雅医院中心实验室完成。SD大鼠110只,雌雄各半,随机抽签法分为5组,即正常对照组、假手术组、雷尼替丁组、健胃愈疡组,各20只;模型组30只。以Okabe改良法复制大鼠实验性胃溃疡,假手术组仅以生理盐水代替乙酸注入玻管内。造模后24h,雷尼替丁组、健胃愈疡组大鼠分别灌服盐酸雷尼替丁和健胃愈疡颗粒(药物组成为:柴胡、党参、白芍、延胡索、白芨、珍珠层粉、青黛、甘草,湖南湘雅制药有限公司生产)药液10mL/kg,分别相当于2.70,1.62g/kg,1次/d。假手术组、模型组灌服蒸馏水10mL/kg。10d后各组中随机取出10只大鼠剖腹取胃(处死前大鼠禁食24h),90d时将模型组20只大鼠再分为模型复发组和模型非复发组,各10只;除正常对照组、假手术组、模型非复发组大鼠腹腔内注射生理盐水外,其余各组大鼠腹腔内注射白细胞介素1,1μg/kg;在注射48h,大鼠禁食24h后,剖腹取胃。观察其对胃溃疡大鼠胃黏膜氨基己糖及磷脂含量、溃疡指数和胃黏膜血流的影响,并用RT-PCR观察乳癌相关肽乳癌相关肽和血小板活化因子表达的变化。结果:实验动物110只,全部进入结果分析。①模型组10,92d胃黏膜血流均低于正常对照组(P<0.01);健胃愈疡组同期胃黏膜血流均高于模型组(P<0.01)。②健胃愈疡组和雷尼替丁组10d溃疡指数均低于模型组(P<0.01,P<0.05);模型复发组、健胃愈疡组和雷尼替丁组92d溃疡指数均高于模型组(P<0.01);健胃愈疡组10,92d溃疡指数及复发率均低于雷尼替丁组(P<0.05,P<0.01)。③模型组10,92d氨基己糖和磷脂含量均低于正常对照组(P<0.01)。健胃愈疡组10,92d氨基己糖和磷脂含量均高于模型组和雷尼替丁组(P<0.01)。溃疡指数与氨基已糖、磷脂含量呈负相关(r=-0.957,-0.960,P<0.01)。④健胃愈疡组和雷尼替丁组10d乳癌相关肽mRNA表达较正常组和假手术组提高,血小板活化因子mRNA的表达下调(P<0.01),健胃愈疡组两指标表达变化较雷尼替丁组显著(P<0.01);模型复发组、健胃愈疡组和雷尼替丁组92d乳癌相关肽mRNA、血小板活化因子mRNA的表达同组10d比较差异无显著性意义(P>0.05);模型组乳癌相关肽mRNA、血小板活化因子mRNA的表达同组10d比较差异有显著性意义(P<0.01)。结论:健胃愈疡颗粒可提高乳癌相关肽mRNA及下调血小板活化因子mRNA的表达,影响胃黏膜氨基己糖及磷脂含量,可能是其促进溃疡愈合的机制之一。  相似文献   
7.
目的:目前临床进行隧道法舌根射频治疗时,其作用参数的设置仍缺乏统一的标准,故通过计算机三维重建射频损伤区域,分析猪舌根射频损伤体积与射频能量、时间的关系,从中得出应用舌根隧道法射频治疗的最佳作用能级和作用时间。 方法:实验于2006-06/2007-05在上海交通大学耳鼻喉科研究所完成。将36只实验用猪以射频作用能级1,2,3,4,5,6随机分成6组,每组6头猪,各个猪舌的作用时间分别设置为2,5,10,15,20,25s。用Coblation射频发生仪及Reflex55刀头进行猪舌根射频操作。射频作用后的舌根组织行连续冰冻切片,苏木精-伊红染色后,进行序列组织切片的全貌二维图像采集,对拟重建的结构进行边界提取和图像分割。将提取分割图像导入Image-Pro Solution图像处理软件,利用3D Constructor插件进行三维重建,并根据设定参数进行体积计算。用SPSS10.0统计学软件对所测数据进行统计学分析。 结果:①作用能级固定时,舌根组织射频损伤体积随时间延长而增大,符合Logarithmic回归曲线。②作用时间固定时,舌根组织射频损伤体积随能级增大而增大,符合直线回归。③射频损伤体积随能量增大而增加亦符合Logarithmic回归曲线。④Coblation射频治疗系统在能级6时,在作用10s之前,损伤体积随作用时间增加而迅速增加,其后变化趋势平缓,超过20s后损伤体积无显著增加。 结论:①舌根区域射频治疗时,舌根组织射频损伤体积与时间或能量呈Logarithmic曲线相关,与能级呈直线相关。②Coblation射频治疗系统在能级6时,最佳作用时间范围为10-20s。  相似文献   
8.
Grog is an additive material that plays important roles in ceramic making. It improves the fabrication process of green bodies as well as the physical properties of fired bodies. Few low-cost materials and wastes have found their application as grog in recent years, thus encouraging the replacement of commercial grogs with cost-saving materials. Coal fly ash, a combustion waste produced by coal-fired power plant, has the potential to be converted into grog owing to its small particle sizes and high content of silica and alumina. In this study, grog was derived from coal fly ash and mixed with kaolin clay to produce ceramics. Effects of the grog addition on the resultant ceramics were investigated. It was found that, to a certain extent, the grog addition reduced the firing shrinkage and increased the total porosity of the ceramics. The dimensional stability of the ceramics at a firing temperature of 1200 °C was also not noticeably affected by the grog. However, the grog addition in general had negative effects on the biaxial flexural strength and refractoriness of the ceramics.  相似文献   
9.
Statement of problemThe 2-color mixing ability test has been recently introduced for objective assessment of masticatory performance. However, the ideal bicolor specimens have not yet been identified, and the color analysis of digital images requires improvement.PurposeThe purpose of this clinical study was to formulate a custom-made, 2-color chewing gum for the mixing ability test and to develop an image-processing method for color mixing analysis.Material and methodsSpecimens of red-green (RG) chewing gum were prepared as a test food. Twenty dentate participants (10 men, 10 women; mean age 21 years) took part in this study. Each participant masticated 1 piece of RG gum for 3, 6, 9, 15, and 25 cycles, and this task was repeated 3 times consecutively (total n=15 for each participant). The boluses were retrieved and flattened to 1-mm-thick wafers and scanned with a flatbed scanner. The digital images were analyzed using ImageJ software equipped with a custom-built plug-in to measure the geometric dispersion (GD) of baseline red segment. The predictive criterion validity of this method was determined by correlating GD to the number of mastication cycles. The hardness and mass of RG chewing gum were measured before and after mastication. Hardness loss (%) and mass loss (%) were then calculated and compared with those of a commercially available chewing gum.ResultsThe 2-way repeated-measures ANOVA with post hoc Bonferroni test showed that GD was able to discriminate among the groups of different numbers of mastication cycles (P<.001). Pearson correlation coefficient confirmed the significant correlation between GD and the number of mastication cycles (r=0.90, P<.001). The hardness loss and mass loss of RG chewing gum were significantly lower than those of commercial chewing gum (P<.001).ConclusionsThe newly formulated chewing gum provides an appropriate test food material for masticatory performance assessment. The new image-processing method discriminated among the different levels of color mixture and quantified the mixing ability.  相似文献   
10.
The human immunodeficiency virus (HIV) epidemic has had a profound influence on the epidemiology of tuberculosis (TB). The potential for HIV-associated TB cases to transmit M. tuberculosis and to produce a secondary increase in TB morbidity is unknown. A cross-sectional study was carried out to compare the prevalence of M. tuberculosis infection among the household contacts of HIV-positive and HIV-negative pulmonary tuberculosis (PTB) patients. Records of tuberculin (Mantoux) tests administered during routine contact investigations at the Chest Clinic, Hospital Kota Bharu, from 1999 to 2000 were reviewed. The HIV status of the patients was based on the results of ELISA tests while information on household contacts was gathered during visits to their houses. Ninety-four contacts of 39 HIV-negative patients and 44 contacts of 17 cases of HIV-positive patients were included in this preliminary study. 30% (12/40) of the contacts of HIV-positive PTB had a positive tuberculin compared with 52.8% (47/ 94) of the contacts of HIV-negative patients [OR = 0.41, 95% Confidence interval (CI) 0.17 - 0.97; p = 0.016]. The difference was still significant after performing multivariate logistic regression analysis to adjust for variables associated with infectiousness of TB (adjusted OR = 0.24, 95% CI 0.07 - 0.87; p = 0.03). This study has shown that HIV-infected PTB patients are less infectious to their contacts than HIV-negative patients. The presence of MV in the community may not necessitate a change of the current policy of the management of contacts.  相似文献   
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