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991.
Eng Chee Heng Saiful Anuar Karsani Mariati Abdul Rahman Noor Aini Abdul Hamid Zalina Hamid Wan Zurinah Wan Ngah 《European journal of nutrition》2013,52(7):1811-1820
Purpose
Tocotrienol possess beneficial effects not exhibited by tocopherol. In vitro studies using animal models have suggested that these effects are caused via modulation of gene and protein expression. However, human supplementation studies using tocotrienol-rich isomers are limited. This study aims to identify plasma proteins that changed in expression following tocotrienol-rich fraction (TRF) supplementation within two different age groups.Methods
Subjects were divided into two age groups—32 ± 2 (young) and 52 ± 2 (old) years old. Four subjects from each group were assigned with TRF (78 % tocotrienol and 22 % tocopherol, 150 mg/day) or placebo capsules for 6 months. Fasting plasma were obtained at 0, 3, and 6 months. Plasma tocopherol and tocotrienol levels were determined. Plasma proteome was resolved by 2DE, and differentially expressed proteins identified by MS. The expressions of three proteins were validated by Western blotting.Results
Six months of TRF supplementation significantly increased plasma levels of tocopherols and tocotrienols. Proteins identified as being differentially expressed were related to cholesterol homeostasis, acute-phase response, protease inhibitor, and immune response. The expressions of Apolipoprotein A-I precursor, Apolipoprotein E precursor, and C-reactive protein precursor were validated. The old groups showed more proteins changing in expression.Conclusions
TRF appears to not only affect plasma levels of tocopherols and tocotrienols, but also the levels of plasma proteins. The identity of these proteins may provide insights into how TRF exerts its beneficial effects. They may also be potentially developed into biomarkers for the study of the effects and effectiveness of TRF supplementation. 相似文献992.
993.
994.
Fatemeh B. Rassouli Maryam M. Matin Ahamd Reza Bahrami Kamran Ghaffarzadegan Hamid Cheshomi Sara Lari Bahram Memar Mun Seng Kan 《Tumour biology》2013,34(5):2909-2920
Digestive system cancers are listed among the ten top causes of cancer-related death worldwide. Cancer stem cells (CSCs) are malignant cells that share some of their characteristics with normal stem cells, including self-renewal and multipotency, and also cancer cells, such as drug resistance and metastasis. Despite many reports on CSCs with digestive system origin, identification and characterization of esophageal CSCs have remained elusive. To examine the validity of routine SC, cancer cell and CSC markers in KYSE30 cells, derived from esophageal carcinoma, cells were first characterized by immunofluorescence and RT-PCR techniques, and then the significance of candidate biomarkers was evaluated in retinoic acid-treated cells by flow cytometry and/or real-time RT-PCR. Meanwhile, to study CD15 (a newly introduced CSC marker) expression in digestive tract cancers, human normal and tumoral tissues of esophagus, stomach, and colon were analyzed by immunohistochemistry. Using several experimental approaches, we show that CD44, but not CD15, could serve as a reliable marker for undifferentiated malignant squamous cells of esophagus. In conclusion, our study confirms the role of CD44 as a CSC marker in KYSE30 cells, an esophageal squamous cell carcinoma cell line, and for the first time indicates the expression of CD15 in non-neural stem-like cancer cells. Although the importance of CD15 was not indicated in diagnosis of digestive cancers, further studies are needed to better understand the biological identity and function of this molecule in non-neural malignancies. 相似文献
995.
An Investigation of the Differential Effects of Ursane Triterpenoids from Centella asiatica,and Their Semisynthetic Analogues,on GABAA Receptors 下载免费PDF全文
Kaiser Hamid Irene Ng Vikram J. Tallapragada Linda Váradi David E. Hibbs Jane Hanrahan Paul W. Groundwater 《Chemical biology & drug design》2016,88(3):386-397
The ursane triterpenoids, asiatic acid 1 and madecassic acid 2 , are the major pharmacological constituents of Centella asiatica, commonly known as Gotu Kola, which is used traditionally for the treatment of anxiety and for the improvement of cognition and memory. Using the two‐electrode voltage‐clamp technique, these triterpenes, and some semisynthetic derivatives, were found to exhibit selective negative modulation of different subtypes of the GABAA receptor expressed in Xenopus laevis oocytes. Despite differing by only one hydroxyl group, asiatic acid 1 was found to be a negative modulator of the GABA‐induced current at α1β2γ2L, α2β2γ2L and α5β3γ2L GABAA receptors, while madecassic acid 2 was not. Asiatic acid 1 exhibited the greatest effect at α1β2γ2L (IC50 37.05 μm ), followed by α5β3γ2L (IC50 64.05 μm ) then α2β2γ2L (IC50 427.2 μm ) receptors. Conversion of the carboxylic acid group of asiatic acid 1 to a carboxamide group (2α,3β,23‐trihydroxy‐urs‐12‐en‐28‐amide 5 ) resulted in enhanced inhibition at both the α1β2γ2L (IC50 14.07 μm ) and α2β2γ2L receptor subtypes (IC50 28.41 μm ). The results of this study, and the involvement of α5‐containing GABAA receptors in cognition and memory, suggest that asiatic acid 1 may be a lead compound for the enhancement of cognition and memory. 相似文献
996.
Chetna Kharbanda Mohammad Sarwar Alam Hinna Hamid Kalim Javed Sameena Bano Yakub Ali Abhijeet Dhulap Perwez Alam M. A. Qadar Pasha 《Chemical biology & drug design》2016,88(3):354-362
Piperine is an alkaloid responsible for the pungency of black pepper. In this study, piperine isolated from Piper nigrum L. was hydrolyzed under basic condition to obtain piperic acid and was used as precursor to carry out the synthesis of twenty piperine derivatives containing benzothiazole moiety. All the benzothiazole derivatives were evaluated for their antidiabetic potential by OGT test followed by assessment of active derivatives on STZ‐induced diabetic model. It was observed that nine of twenty novel piperine analogues ( 5b, 6a‐h) , showed significantly higher antidiabetic activity in comparison with rosiglitazone (standard). Furthermore, these active derivatives were evaluated for their action as PPAR‐γ agonists demonstrating their mechanism of action. The effects on body weight, lipid peroxidation, and hepatotoxicity after administration with active derivatives were also studied to further establish these derivatives as lead molecules for treatment of diabetes with lesser side‐effects. 相似文献
997.
Abstract The diffusion of 2-hydroxyethylmediacrylate (HEMA) and triethylene glycol dimethacrylate (TEGDMA) from light cured bonding resin-composite resin restorations through human carious dentin was investigated. Extracted human molar teeth with different degrees of caries were obtained from consenting donors. Teeth were classified into three groups according to caries severity (mild, moderate and severe) using subjective criteria. The outer carious lesions were then removed guided by a proprietary caries detector dye. Teeth with exposure of the pulp space after caries removal were excluded from the study. A polypropylene chamber was attached to the cemento-enamel junction of each tooth to contain 1 ml distilled water. Each cavity was restored with a HEMA containing bonding resin then a TEGDMA-containing resin composite. Water samples were retrieved over a lime course and analyzed by high performance liquid chromatography. There was great variation between teeth in HEMA and TEGDMA permeability. The cumulative amounts released were of similar magnitude to those observed in non-carious teeth for the mild and moderately-severe groups. However, the cumulative amounts released were markedly greater in severely carious teeth than in those with moderate or mild caries. 相似文献
998.
Effect of misoprostol, a prostaglandin E1 analog, on orthodontic tooth movement in rats. 总被引:2,自引:0,他引:2
Ali Reza Sekhavat Kazem Mousavizadeh Hamid Reza Pakshir Fatemeh Sari Aslani 《American journal of orthodontics and dentofacial orthopedics》2002,122(5):542-547
The purpose of this study was to investigate the effects of oral administration of misoprostol, a prostaglandin E1 analog, on orthodontic tooth movement and root resorption in rats. Sixty-four male Sprague-Dawley rats that initially weighed 250 +/- 20 g were used in this study. The animals were randomly assigned to 1 of 6 experimental and 2 control (nonappliance and appliance) groups. The experimental groups received 2.5, 5.0, 10.0, 25.0, 50.0, and 100.0 microg/kg misoprostol by gastric lavage every 24 hours for 2 weeks. A fixed orthodontic appliance consisting of a nickel-titanium closed-coil spring, 5.0 mm long was ligated between the maxillary right incisor and the maxillary right first molar. The initial activating force was 60 g. For analysis of root resorption, 99 maxillary right and left first molars from 61 animals were chosen. Serial histologic sections of the mesial root of the maxillary first molars were made, and histologic analysis of root resorption on the mesial and distal surfaces was performed. The results showed that oral misoprostol did increase the amount of orthodontic tooth movement in all the experimental groups compared with the appliance control group. This increase was statistically significant in doses of 10.0, 25.0, 50.0, and 100.0 microg/kg (P <.001). However, there were no statistically significant differences among these 4 different doses. There were no statistically significant differences in the amount of root resorption among the groups. However, a trend toward more root resorption was registered. On the basis of these findings, oral misoprostol can be used to enhance orthodontic tooth movement with minimal root resorption. 相似文献
999.
Malak Shakeri Hamid Kohram Abdolhossein Shahverdi Ahmad Zare Shahneh Faranak Tavakolifar Mehdi Pirouz Hossein Moradi Shahrebabak Morteza Koruji Hossein Baharvand 《Journal of assisted reproduction and genetics》2013,30(3):325-332
Purpose
Spermatogonial stem cells are affected by the interactions of extrinsic signals produced by components of the microenvironment niche, in addition to the chemical and physical properties of the extracellular matrix. Therefore, this study was initiated to assess the interaction of these cells on a synthetic nanofibrillar extracellular matrix that mimicked the geometry and nanotopography of the basement membrane for cellular growth.Methods
This study has used a variety of experimental approaches to investigate the interaction of mouse neonatal-derived spermatogonial stem-like cells on a synthetic random oriented three-dimensional nanofibrillar matrix composed of electrospun polyamide nanofibers (Ultra-Web™).Results
Spermatogonial stem-like cell colonies were characterized by their ability to express α6-integrin, Thy-1, PLZF, and β1-integrin. After culture of cells on the nanofibrillar surfaces for 7 days, the number of colonies, the number of cells in each colony, and the average area of colonies were increased (P < 0.05). However, the expression difference of related markers in both groups was not significant. A significantly higher proliferation and survival was observed in the nanofibrillar group (P < 0.05). After transplantation into the testes of busulfan-treated adult mice, spermatogonial stem-like cell colonies that were cultured on the nanofibrillar surface demonstrated functionality, as verified by their ability to migrate to the seminiferous basal membrane, where they produced additional colonies.Conclusions
These results have suggested that electrospun nanofibrillar surfaces could provide a more favorable microenvironment for in vitro short term culture of spermatogonial stem-like cell colonies. 相似文献1000.
Mamdouh Abdulrhman Mohamed El Hefnawy Rasha Ali Iman Abdel Hamid Ahmad Abou El-Goud Doaa Refai 《Complementary therapies in clinical practice》2013,19(1):15-19
This study was a case control cross sectional study that was conducted on 50 patients with type 1 diabetes mellitus and 30 controls without diabetes. The mean age of patients was 10.02 years. Oral sugar tolerance tests using glucose, sucrose and honey and measurement of fasting and postprandial serum C-peptide levels were done for all subjects in three separate sittings. The glycemic index (GI) and the peak incremental index (PII) were then calculated for each subject. Honey, compared to sucrose, had lower GI and PII in both patients and controls (P < 0.01). In both patients and controls, the increase in the level of C-peptide after honey was significant when compared with either glucose or sucrose (P < 0.01). Conclusion: Because of its possible stimulatory effect on diseased beta cells, honey might be considered in future therapeutic trials targeting beta cells of pancreas. 相似文献