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Woods BP, Orlandi M, Huang CY, Sigman MS, Doyle AG. Nickel-Catalyzed Enantioselective Reductive Cross-Coupling of Styrenyl Aziridines. J Am Chem Soc 2017; 139:5688-5691. [PMID: 28406622 DOI: 10.1021/jacs.7b03448] [Citation(s) in RCA: 174] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A Ni-catalyzed reductive cross-coupling of styrenyl aziridines with aryl iodides is reported. This reaction proceeds by a stereoconvergent mechanism and is thus amenable to asymmetric catalysis using a chiral bioxazoline ligand for Ni. The process allows facile access to highly enantioenriched 2-arylphenethylamines from racemic aziridines. Multivariate analysis revealed that ligand polarizability, among other features, influences the observed enantioselectivity, shedding light on the success of this emerging ligand class for enantioselective Ni catalysis.
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Li J, Dai AG, Huang CY, Hu RC. [Effect of Krüppel like zinc finger transcription factor 2 on γ-glutamylcysteine synthetase in bronchial epithelial cells of chronic obstructive pulmonary disease]. ZHONGHUA YI XUE ZA ZHI 2017; 97:112-118. [PMID: 28088955 DOI: 10.3760/cma.j.issn.0376-2491.2017.02.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To research the regulation effects of Krüppel like zinc finger transcription factor 2 (KLF2) on γ-glutamylcysteine synthetase (γ-GCS) in airway epithelial cells of chronic obstructive pulmonary disease (COPD). Methods: (1) Human specimen experiment: lung tissue of pulmonary lobectomy patients with lung cancer with or without COPD was collected from Department of Thoracic Surgery of Hunan Cancer Hospital from December 2008 to December 2009. The patients were divided into COPD group and control group without COPD. The levels of KLF2, γ-GCS mRNA and protein expression in lung tissues were measured by immunohistochemistry and in situ hybridization (ISH). Then, the correlation between KLF2 and γ-GCS mRNA and protein expression levels were analyzed, as well as the correlation between KLF2 or γ-GCS protein and smoking index, percentage of forced expiratory volume in one second to predicted value (FEV1%), percentage of forced expiratory volume in one second to forced vital capacity (FVC/FEV1). (2) Animal experiment: the primary bronchial epithelial cells of rats were extracted by enzyme digestion. After 6 hours of incubation with 10% tobacco smoke extract (TSE), cellular glutathione (GSH) was measured by enzyme linked immunosorbent assay (ELISA) method. The cells were transfected by specific inhibitor of KLF2 through the liposom, which inhibited the protein expression of KLF2. Then, the cells were divided into KB group (blank control group without any treatment), KB+ TSE group (treated with TSE), NC group (control group transfected with miRNA), NC+ TSE group (treated with miRNA and TSE), 92a group (transfected with KLF2 inhibitor), 92a+ TSE group (treated with KLF2 inhibitor transfection and TSE) based in the treatment. After that, the changes of KLF2 and γ-GCS mRNA and protein expression in the cells of each group were measured by reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot method. Results: (1) Human specimen experiment: The expressions of KLF2 mRNA, protein and γ-GCS mRNA, protein in the lung tissue of COPD patients were strong positive and higher than those in control group (0.32±0.04 vs 0.19±0.03, 0.35±0.05 vs 0.22±0.03; 0.28±0.03 vs 0.16±0.03, 0.31±0.05 vs 0.21±0.03; all P<0.01). Linear correlation analysis showed that KLF2 mRNA and protein were positively correlated with γ-GCS mRNA and protein (r=0.705, 0.722; both P<0.01). The KLF2 and γ-GCS protein were positively correlated with smoking index, FEV1% and FEV1/FVC (r=0.552, 0.728, 0.670, and r=0.631, 0.727, 0.657; all P<0.01). (2) Animal experiment: The level of GSH in KB+ TSE group was significantly higher than that in KB group[(28.05±2.04) vs (7.27±0.33) nmol/mg, P<0.01]. The KLF2 mRNA, protein and γ-GCS mRNA, protein in KB+ TSE group (1.715±0.026, 1.842±0.028 and 2.117±0.067, 1.879±0.065) were higher than those in KB group (1.130±0.017, 1.177±0.033 and 1.378±0.053, 1.177±0.042; all P<0.05), and those in 92a group (0.472±0.028, 0.634±0.025 and 0.582±0.025, 0.554±0.021) were significantly lower than those in KB group, NC group (1.047±0.056, 1.092±0.045 and 1.303±0.037, 1.252±0.037), and those in TSE+ 92a group (0.262±0.017, 0.288±0.017 and 0.337±0.022, 0.321±0.022) were significantly lower than those in KB+ TSE group, 92a group and NC+ TSE group (1.576±0.036, 1.646±0.066 and 1.948±0.093, 1.843±0.078) (all P<0.05). Conclusion: KLF2 exerts antioxidative effect by regulating the expression of γ-GCS in the bronchial epithelial cells of chronic obstructive pulmonary disease.
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Wang LH, Liu CK, Chen CH, Kao LT, Lin HC, Huang CY. No increased risk of coronary heart disease for patients receiving androgen deprivation therapy for prostate cancer in Chinese/Taiwanese men. Andrology 2015; 4:128-32. [PMID: 26711703 DOI: 10.1111/andr.12141] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 10/19/2015] [Accepted: 11/01/2015] [Indexed: 11/28/2022]
Abstract
The relationship between androgen deprivation therapy (ADT) and coronary heart disease (CHD) remains controversial. Furthermore, the majority of such studies focused on Caucasian populations, and there is still a paucity of studies among Asian populations. This population-based study aimed to investigate the relationship between ADT and CHD in an ethnic Chinese (i.e., Taiwanese) population. We used data sourced from the Taiwan 'Longitudinal Health Insurance Database'. This study included 1278 patients with prostate cancer in the study group and 1278 subjects without prostate cancer in the comparison group. Each patient was individually tracked for a 3-year period to identify those who had subsequently received a diagnosis of CHD. The results showed that the incidence rate of CHD during the 3-year follow-up period was 4.69 (95% CI: 2.99-5.48) per 100 person-years and 2.67 (95% CI: 2.15-3.27) per 100 person-years for the study and comparison cohort, respectively. The Cox proportional hazard regression showed that the hazard ratio for CHD during the 3-year follow-up period for prostate cancer patients was 1.65 (95% confidence interval (CI) = 1.25-2.16) compared with comparison subjects after adjusting for patients' geographic location, monthly income, urbanization level, hypertension, diabetes, hyperlipidemia, and stroke. However, we failed to find a significant difference in the adjusted hazard of CHD during the 3-year follow-up period between prostate cancer patients who did and those who did not receive ADT (hazard ratio = 1.12, 95% CI = 0.79-1.59). We concluded that prostate cancer but not ADT was significantly associated with CHD. In addition, a common cause of prostate cancer and coronary heart disease could exist.
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Hsu HL, Hsu HP, Yu BF, Lu TM, Huang CY, Shih CC, Cheng BC, Hsu CP. Long-term results of coronary artery bypass grafting in patients with dialysis-dependent renal failure. THE JOURNAL OF CARDIOVASCULAR SURGERY 2015; 56:809-816. [PMID: 26088012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
AIM Coronary artery disease is the main cause of mortality and morbidity in dialysis-dependent renal failure patients. Both the prevalence and incidence of renal failure are high in Taiwan. However, there were few reports exploring the outcome of coronary aortic bypass grafting (CABG) in these patients. The aim of this study was to determine the survival outcome and risk factors for mortality from CABG in this population. METHODS The operative, early postoperative and late results of 170 dialysis patients undergoing isolated coronary artery bypass grafting from January, 2000 to January, 2012 were retrospectively reviewed. Operative mortality, long-term survival, and risk factors were analyzed. RESULTS One hundred and seventeen patients (68.8%) were male, and the mean age was 61.5±10.3 years (range, 34-86 years). Follow-up was 40.3±32.1 months. Operative mortality was 8.2%. Actuarial survival, including operative mortality, was 81±3% at 1 year, 68±4% at 3 years, 58±5% at 5 years and 49±6% at 10 years, better than the natural course of dialysis-dependent renal failure patients. Age, emergent operation, postoperative ventricular tachycardia or fibrillation, postoperative intra-aortic balloon pump insertion, gastrointestinal bleeding, and left internal mammary artery graft were significant predictors of operative or long term mortality. Most causes of late death were due to infection or cardiac events. CONCLUSION CABG in dialysis patients is associated with a higher incidence of complications, but has acceptable mortality. CABG is beneficial in this population. Internal mammary artery grafting may provide more favorable long term outcomes.
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Ma XG, Liu YF, Liu N, Ren JC, Xu GW, Chu L, Lv H, Huang CY, Zhu YF. Magnetic mediation effect of a C impurity in a Mn-doped Zn₁₂O₁₂ nanocluster: a case of multiple exchange interactions. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:335301. [PMID: 26235128 DOI: 10.1088/0953-8984/27/33/335301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The stability and exchange interaction mechanism of a doped Zn12O12 cluster with Mn and C atoms were investigated by first-principles calculations. For the Mn-doped Zn12O12 cluster, it is identified that a superexchange interaction deriving the hybridization between the Mn 3d(2/x)-2/y and O 2p(xy) orbitals dominates the Mn(↑)-Mn(↓) antiferromagnetic coupling, although a direct exchange interaction deriving the Mn-Mn bonding is also found. In order to turn the Mn spin state in the Mn-doped Zn12O12 cluster, C doping is undertaken to change the magnetic interactions of these impurities. It is proved that the C incorporation into the Mn-doped Zn12O12 cluster destroys the short-ranged antiferromagnetic coupling, where multiple exchange interactions take over, including the direct exchange interaction and the kinetic p-d exchange interaction partially due to the geometric distortion and surface effect with dangling bonds (sp(2)-like hybrids). It is concluded that the kinetic p-d exchange interaction plays a dominant role in Mn/C-doped Zn12O12 clusters.
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Chiu YL, Kao S, Lin HC, Liu SP, Huang CY. Benign prostatic enlargement is not associated with diabetes: a population-based study. Andrology 2015. [PMID: 26216209 DOI: 10.1111/andr.12069] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The association between diabetes and benign prostatic hyperplasia remains inconclusive. In this case-control study, we examined the association of diabetes with benign prostatic enlargement (BPE) using the Longitudinal Health Insurance Database 2000 in Taiwan. In total, 20 152 patients with BPE as cases and 20 152 age-matched patients without BPE were included as controls. Conditional logistic regression analyses were performed to calculate the odds ratio (OR) and corresponding 95% CI for having been previously diagnosed with diabetes between cases and controls. We found that of the 40 304 sampled patients, 9492 (23.6%) had a history of diabetes before the index date. This mean age for the sampled patients was 65.9 with a standard deviation of 12.0 years. A Chi-squared test revealed that there was a significant difference in the prevalence of prior diabetes between cases and controls (25.3% vs. 21.8%, p < 0.001). The conditional logistic regression found that the OR of prior diabetes for cases was 1.21 (95% CI = 1.15-1.27) compared with controls. However, after adjusting for geographic region, monthly income, urbanization level, hypertension, coronary heart disease (CHD), hyperlipidemia, tobacco use disorder, and obesity, the association between prior diabetes and BPE did not reach a statistically significant level (OR = 1.03, 95% CI = 0.98-1.08). In addition, it was noteworthy that hypertension (OR = 1.25, 95% CI = 1.20-1.31), CHD (OR = 1.40, 95% CI = 1.32-1.48), and hyperlipidemia (OR = 1.30, 95% CI = 1.24-1.36) were all significantly associated with BPE. We found that men with a diagnosis of diabetes were not significantly associated with BPE after adjusting for patient's sociodemographic characteristics and comorbidities.
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Huang CY, Chung SD, Kao LT, Lin HC, Wang LH. Statin Use Is Associated with Bladder Pain Syndrome/Interstitial Cystitis: A Population-Based Case-Control Study. Urol Int 2015; 95:227-32. [PMID: 26184102 DOI: 10.1159/000431185] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 05/05/2015] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Statin may induce epithelial dysfunction of the bladder urothelium. Epithelial dysfunction was proposed as one of the major potential etiologies for bladder pain syndrome/interstitial cystitis (BPS/IC). In this study, we examined the association between statin use and BPS/IC using a population-based study. SUBJECTS AND METHODS This case-control study used the Taiwan Longitudinal Health Insurance Database. In total, 815 female subjects with BPS/IC and 4075 randomly selected female controls were included. We used a conditional logistic regression to compute the odds ratio (OR) for having previously used statins between cases and controls. RESULTS A conditional logistic regression analysis showed that the OR of prior statin users for cases was 1.52 (95% confidence interval (CI): 1.19-1.94) compared to controls after adjusting for diabetes, hypertension, coronary heart disease, obesity, chronic pelvic pain, irritable bowel syndrome, fibromyalgia, chronic fatigue syndrome, depression, panic disorder, migraines, sicca syndrome, allergies, endometriosis, and asthma. Furthermore, adjusted ORs of regular and irregular statin use for cases were 1.58 (95% CI: 1.20-2.08) and 1.53 (95% CI: 1.02-2.31), respectively, compared to controls. CONCLUSION We concluded that there was an association between statin use and BPS/IC.
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Garland CJ, Smirnov SV, Bagher P, Lim CS, Huang CY, Mitchell R, Stanley C, Pinkney A, Dora KA. TRPM4 inhibitor 9-phenanthrol activates endothelial cell intermediate conductance calcium-activated potassium channels in rat isolated mesenteric artery. Br J Pharmacol 2014; 172:1114-23. [PMID: 25323322 DOI: 10.1111/bph.12985] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 10/08/2014] [Accepted: 10/09/2014] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND AND PURPOSE Smooth muscle transient receptor potential melastatin 4 (TRPM4) channels play a fundamental role in the development of the myogenic arterial constriction that is necessary for blood flow autoregulation. As TRPM4 channels are present throughout the vasculature, we investigated their potential role in non-myogenic resistance arteries using the TRPM4 inhibitor 9-phenanthrol. EXPERIMENTAL APPROACH Pressure and wire myography were used to assess the reactivity of rat arteries, the latter in combination with measurements of smooth muscle membrane potential. Immunohistochemistry (IHC) and endothelial cell (EC) calcium changes were assessed in pressurized vessels and patch clamp measurements made in isolated ECs. KEY RESULTS The TRPM4 inhibitor 9-phenanthrol reversibly hyperpolarized mesenteric arteries to circa EK and blocked α1 -adrenoceptor-mediated vasoconstriction. Hyperpolarization was abolished and vasoconstriction re-established by damaging the endothelium. In mesenteric and cerebral artery smooth muscle, 9-phenanthrol hyperpolarization was effectively blocked by the KCa 3.1 inhibitor TRAM-34. 9-Phenanthrol did not increase mesenteric EC [Ca(2+)]i , and Na(+) substitution with N-methyl-D-glucamine only increased the muscle resting potential by 10 mV. Immunolabelling for TRPM4 was restricted to the endothelium and perivascular tissue. CONCLUSIONS AND IMPLICATIONS These data reveal a previously unrecognized action of the TRPM4 inhibitor 9-phenanthrol - the ability to act as an activator of EC KCa 3.1 channels. They do not indicate a functionally important role for TRPM4 channels in the reactivity of non-myogenic mesenteric arteries.
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Wang ZX, Huang CY, Hua YP, Huang WQ, Deng LH, Liu KX. Dexmedetomidine reduces intestinal and hepatic injury after hepatectomy with inflow occlusion under general anaesthesia: a randomized controlled trial. Br J Anaesth 2014; 112:1055-64. [PMID: 24771805 DOI: 10.1093/bja/aeu132] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND We compared intestinal, hepatic, and other organ function after hepatic portal occlusion with or without dexmedetomidine administration under general anaesthesia. METHODS In this prospective, randomized double-blind investigation, 44 patients undergoing elective hepatectomy with inflow occlusion were randomized into a dexmedetomidine group or a control group. The dexmedetomidine group received an initial dexmedetomidine loading dose of 1 μg kg(-1) over 10 min followed by a maintenance dose of 0.3 μg kg(-1) h(-1). In the control group, 0.9% sodium chloride was administered. The primary outcome was serum diamine oxidase (DAO) activity reflecting intestinal injury. The secondary outcomes included variables reflecting intestinal, hepatic, kidney, and cardiopulmonary function, and biomarkers of oxidative stress and systemic inflammatory response. RESULTS DAO activity was lower in the dexmedetomidine group than in the control group at 6 and 24 h after liver reperfusion [9.77 (1.07) vs14.29 (1.43) units ml(-1), P=0.021; 9.67 (0.98) vs 13.97 (1.31) units ml(-1), P=0.017]. d-lactate acid levels were lower during 1-72 h after liver reperfusion compared with the control group (all P<0.05). Also, the intestinal injury severity grade was decreased by dexmedetomidine (P=0.038). The biomarkers reflecting liver injury increased over time, but were lower in the dexmedetomidine group (all P<0.05), while the variables reflecting cardiopulmonary and renal function showed no differences between the groups (all P>0.05). CONCLUSIONS Dexmedetomidine administered perioperatively attenuates intestinal and hepatic injury in patients undergoing elective liver resection with inflow occlusion without any potential risk. CLINICAL TRIAL REGISTRATION ChiCTR-TRC-11001530, September 2011.
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Chiu KM, Chen RJ, Lin TY, Chen JS, Huang JH, Huang CY, Chu SH. Right mini-parasternotomy may be a good minimally invasive alternative to full sternotomy for cardiac valve operations-a propensity-adjusted analysis. THE JOURNAL OF CARDIOVASCULAR SURGERY 2014:R37Y9999N00A140179. [PMID: 24667339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
AIM Limited realworld data existed for miniparasternotomy approach with good sample size in Asian cohorts and most previous studies were eclipsed by case heterogeneity. The goal of this study was to compare safety and quality outcomes of cardiac noncoronary valve operations by miniparasternotomy and full sternotomy approaches on riskadjusted basis. METHODS From our hospital database, we retrieved the cases of non-coronary valve operations from 1 January 2005 to 31 December 2012, including re-do, emergent, and combined procedures. Estimated EuroScore-II and propensity score for choosing mini-parasternotomy were adjusted for in the regression models on hospital mortality, complications (pneumonia, stroke, sepsis, etc.), and quality parameters (length of stay, ICU time, ventilator time, etc.). Non-complicated cases, defined as survival to discharge, ventilator use not over one week, and intensive care unit stay not over two weeks, were used for quality parameters. RESULTS There were 283 miniparasternotomy and 177 full sternotomy cases. EuroScore-II differed significantly (medians 2.1 vs. 4.7, p<0.001). Propensity scores for choosing miniparasternotomy were higher with lower EuroScore-II (OR=0.91 per 1%, p<0.001), aortic regurgitation (OR=2.3, p=0.005), and aortic non-mitral valve disease (OR=3.9, p<0.001). Adjusted for propensity score and EuroScore-II, mini-parasternotomy group had less pneumonia (OR=0.32, p=0.043), less sepsis (OR=0.31, p=0.045), and shorter non-complicated length of stay (coefficient=7.2 (day), p<0.001) than full sternotomy group, whereas Kaplan-Meier survival, non-complicated ICU time, non-complicated ventilator time, and 30-day mortality did not differ significantly. CONCLUSION The propensity-adjusted analysis demonstrated encouraging safety and quality outcomes for mini-parasternotomy valve operation in carefully selected patients.
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Huang CY, Tehrani J, Ng J, Keall P. SU-E-J-118: Quantifying Intrafractional Prostate Rotation From Cone-Beam Computed Tomography with Radiopaque Markers. Med Phys 2013. [DOI: 10.1118/1.4814330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Kong HY, Cheng DM, Pang W, Sun SD, Liu J, Huang CY, Jiang YG. Homocysteine levels and cognitive function scores measured with MMSE and BCAT of middle-aged and elderly subjects in Tianjin City. J Nutr Health Aging 2013; 17:527-32. [PMID: 23732549 DOI: 10.1007/s12603-013-0026-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE China is proceeding into the aging society. There are near 6 million elderly suffering senile dementia,while cognitive impairment is an important clinical feature in dementia. The factors involved in cognitive dysfunction in the middle-aged and the elderly persons were investigated. DESIGN Cross-sectional study. SETTING Community dwellers and nursing home residents in Tianjin, China. SUBJECTS Total of 662 subjects(284 men and 378 women) aged 55-93. METHODS A designed questionnaire was used to collect their demographic data, information of disease and medication, and life style. Mini-mental state examination (MMSE) and Basic Cognitive Aptitude Tests (BCAT) software were applied to evaluate their cognitive function. Serum total homocysteine (tHcy) level was quantified by enzyme conversion method. A multiple linear stepwise regression analysis was applied to find the influencing factors of cognitive function. RESULTS The average serum tHcy concentrations was 15.95±7.29 μmol/L, while the prevalence of hyperhomocysteinemia (HHE) was 45.4%. The average serum tHcy level and prevalence of HHE were higher in men than those in women after ruling out the age differences. The mean MMSE and BCAT scores were 26.74±2.71 and 50.26±18.84 respectively. The BCAT score was negatively correlated with age and positively correlated with education. Multiple linear stepwise regression equations showed that the P value was less than 0.001, the BCAT regression equation showed that the R2=0.453. Serum tHcy concentration was negatively correlated with total scores of BCAT, digit copy, Chinese character comparison, mental arithmetic, Chinese character rotation and recall answer of mental arithmetic test. Total scores of BCAT were negatively correlated with education, inhabitancy, serum tHcy concentration and age. In addition, Chinese character rotation was correlated with tea consumption. Remembrance and recognition of dual words and nonsense figures was correlated with income level. CONCLUSIONS Hyperhomocysteinemia is associated with cognitive impairment in the middle-aged and the elderly persons in Tianjin. The BCAT scores could well represent the detailed cognitive function in elderly and negatively correlate with age, but positively correlated with education level. Serum tHcy concentration was negatively correlated with total BCAT scores.
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Sun LP, Chen AL, Hung HC, Chien YH, Huang JS, Huang CY, Chen YW, Chen CN. Chrysin: a histone deacetylase 8 inhibitor with anticancer activity and a suitable candidate for the standardization of Chinese propolis. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2012; 60:11748-58. [PMID: 23134323 DOI: 10.1021/jf303261r] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Chinese propolis (CP) is a natural product collected by honeybees and a health food raw material. Previous studies have shown that CP exhibits a broad spectrum of biological activities including anticancer, antioxidant, antibacterial, anti-inflammatory, and antiviral activities. The focuses of the present study were the standardization of CP and the possible mechanisms of its active anticancer ingredients. Nine samples of CP were collected from different locations in China. Analyses of the CP samples revealed that all 9 had similar chemical compositions. Parameters analyzed included the CP extract dry weight, total phenolic content, and DPPH free radical scavenging activities. The active anticancer ingredient was isolated, characterized against human MDA-MB-231 breast cancer cells, and identified as chyrsin, a known potent anticancer compound. Chrysin is present at high levels in all 9 of the CP samples, constituting approximately 2.52% to 6.38% of the CP extracts. However, caffeic acid phenethyl ester (CAPE), another potent active ingredient is present in low levels in 9 samples of CP, constituting approximately 0.08% to 1.71% of the CP extracts. Results from analyses of enzymatic activity indicated that chrysin is a histone deacetylase inhibitor (HDACi) and that it markedly inhibited HDAC8 enzymatic activity (EC(50) = 40.2 μM). In vitro analyses demonstrated that chrysin significantly suppressed cell growth and induced differentiation in MDA-MB-231 cells. In a xenograft animal model (MDA-MB-231 cells), orally administered chrysin (90 mg/kg/day) significantly inhibited tumor growth. Despite the geographical diversity of the 9 samples' botanical origins, their chemical compositions and several analyzed parameters were similar, suggesting that CP is standardized, with chrysin being the major active ingredient. Overall, in vitro and in vivo data indicated that chrysin is an HDAC8 inhibitor, which can significantly inhibit tumor growth. Data also suggested that chrysin might represent a suitable candidate for standardization of CP.
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Lam L, Lau KK, Mok V, Huang CY, Li SW, Wu YM, Chung E, Leung MF, Kong B, Li P. A proposal for an appropriate nomenclature to late-onset cognitive impairment for Hong Kong in the 21st century: dementia revisited. Hong Kong Med J 2012; 18:447-449. [PMID: 23018076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023] Open
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Huang CY, Chi LL, Huang WJ, Chen YW, Chen WJ, Kuo YC, Yuan CM, Chen CN. Growth stimulating effect on queen bee larvae of histone deacetylase inhibitors. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2012; 60:6139-6149. [PMID: 22642680 DOI: 10.1021/jf300815b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Royal jelly (RJ) is a widely used natural food. It is also a major source of nutrition for queen bees and plays a key role in their development. RJ is secreted from the hypopharyngeal and mandibular glands of young adult worker bees. The regulation of gene expression in these two glands may influence the development of queen bees by affecting the content of RJ. This study investigated the epigenetic effects in these two glands in young adult worker bees treated with histone deacetylase inhibitors (HDACis), a U.S. Food and Drug Administration-approved drug, suberoylanilide hydroxamic acid (SAHA), and NBM-HD-1, a novel compound synthesized in this laboratory. Western blot analyses indicated that the levels of acetyl-histone 3 and p21 protein expression in MCF-7 cells increased markedly after treatment with NBM-HD-1. The data proved that NBM-HD-1 was a novel and potent HDACi. Furthermore, a method of affecting epigenetic regulation of the mrjp family gene in the hypopharyngeal and mandibular glands of young adult worker bees was developed by feeding young adult worker bees HDACi. Epigenetic regulation produced several important biological effects. A marked change in the protein composition of the RJ secreted from these treated bees was found. Only the ratio of specific major royal jelly protein 3 (MRJP3) was significantly altered in the treated bees versus the untreated controls. Other MRJP family proteins did not change. This alteration in the ratio of royal jelly proteins resulted in a significant increase in the body size of queen bee larvae. The data seem to suggest that HDACis may play an important role in the epigenetic regulation of the hypopharyngeal and mandibular glands of young adult worker bees. They appear to change mrjp3 gene expression and alter the ratio of MRJP3 protein in RJ. This study presents the first evidence that HDACis are capable of regulating the ratio of MRJP3 proteins in RJ, which has the potential to change the body size of queen bees during their development.
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Liu TY, Chen Y, Wang HH, Huang YL, Chao YC, Tsai KT, Cheng WC, Chuang CY, Tsai YH, Huang CY, Wang DW, Lin CH, Wang JK, Wang YL. Differentiation of bacteria cell wall using Raman scattering enhanced by nanoparticle array. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2012; 12:5004-8. [PMID: 22905567 DOI: 10.1166/jnn.2012.4941] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We have fabricated surface-enhanced Raman scattering (SERS) substrates based on arrays of silver nanoparticles grown on porous anodic alumina templates. Using this nanotechnology platform, label-free and high-speed detection of bacteria are achieved. SERS spectra of various bacteria including Staphylococcus Aureus (Gram-positive bacterium), Klebsiella Pneumoniae (Gram-negative bacterium), and Mycobacterium Smegmatis (Mycobacterium) were recorded. The highly reproducible SERS-based technological platform is capable of differentiating different kinds of bacteria by PCA, LDA, clustering analysis, and SVM methods, which provides promising opportunity for biosensing of clinical microbes.
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Huang WJ, Lin CW, Lee CY, Chi LL, Chao YC, Wang HN, Chiou BL, Chen TJ, Huang CY, Chen CN. NBM-HD-3, a novel histone deacetylase inhibitor with anticancer activity through modulation of PTEN and AKT in brain cancer cells. JOURNAL OF ETHNOPHARMACOLOGY 2011; 136:156-167. [PMID: 21530633 DOI: 10.1016/j.jep.2011.04.034] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 03/17/2011] [Accepted: 04/13/2011] [Indexed: 05/30/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Taiwanese green propolis (TGP) extract contains a variety of chemical components and has proven to have broad-spectrum biological activities, including anticancer, antioxidant, and antimicrobial activities. Propolin G, an active anticancer component of TGP, was isolated and characterized in this study. Histone deacetylase inhibitors (HDACis) have been shown to be effective anticancer agents. The aim of this study was to develop a novel HDACi and investigate its anticancer mechanism. MATERIALS AND METHODS NBM-HD-3, a novel HDACi, was derived from propolin G. Two brain cancer cell lines (c6 and DBTRG-05MG) were used in the anti-proliferation assay. NBM-HD-3 treated cells were analyzed by flow cytometry in the cell cycle assay. The gene expression of NBM-HD-3 treated cells was determined by real-time quantitative PCR. HDAC enzyme assay, confocal microscopy and Western blot assay were used to validate NMB-HD-3 as HDACi. Western blot assay was used for analyzing cell cycle modulation by PTEN and AKT. RESULTS NBM-HD-3 was found to have potent anti-proliferative activity in brain cancer cells (rat C6 glioma and human DBTRG-05MG glioblastoma). Western blot analysis and HDAC enzyme assay indicated that NBM-HD-3 was an HDAC inhibitor. The Western blot data exhibited increased levels of p21, Ac-histone 3, Ac-histone 4, and Ac-tubulin after brain cancer cells being treated with NBM-HD-3. NBM-HD-3 also affected the cell cycle regulators such as p21 and cyclin B1. In the study for its anticancer mechanism, NBM-HD-3 was found to increase PTEN and AKT protein levels significantly, while decreasing p-PTEN and p-AKT levels markedly. CONCLUSION This study demonstrated that the novel compound, NBM-HD-3, is a potent HDAC inhibitor. It produces anticancer activity through modulation of PTEN and AKT in brain cancer cells.
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Chiou WF, Liao JF, Huang CY, Chen CC. 2-Methoxystypandrone represses RANKL-mediated osteoclastogenesis by down-regulating formation of TRAF6-TAK1 signalling complexes. Br J Pharmacol 2011; 161:321-35. [PMID: 20735418 DOI: 10.1111/j.1476-5381.2010.00823.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE 2-Methoxystypandrone (2-MS) is a naphthoquinone isolated from Polygonum cuspidatum, a Chinese herb used to treat bone diseases. Here we have determined whether 2-MS antagonised osteoclast development and bone resorption. EXPERIMENTAL APPROACH RAW264.7 cells were treated with receptor activator of nuclear factor kappaB (NF-kappaB) ligand (RANKL) to induce differentiation into osteoclasts. RT-PCR and Western blot were used to analyse osteoclast-associated gene expression and signalling pathways. KEY RESULTS The number of multinuclear osteoclasts, actin rings and resorption pit formation were markedly inhibited by 2-MS, targeting osteoclast differentiation at an early stage and without significant cytotoxicity. The anti-resorption effect of 2-MS was accompanied by decreasing dendritic cell-specific transmembrane protein and matrix metalloproteinase-9 (MMP-9) mRNA expression. RANKL-increased MMP-9 gelatinolytic activity was also attenuated by concurrent, but not by subsequent addition of 2-MS. 2-MS markedly inhibited not only the RANKL-triggered nuclear translocations of NF-kappaB, c-Fos and nuclear factor of activated T cells c1 (NFATc1), but also the subsequent NFATc1 induction. Degradation of IkappaB and phosphorylation of mitogen-activated protein kinases were also suppressed. RANKL facilitated the formation of signaling complexes of tumour necrosis factor receptor-associated factor 6 and transforming growth factor beta-activated kinase 1 (TRAF6-TAK1), important for osteoclastogenesis and formation of such signalling complexes was prevented by 2-MS. CONCLUSIONS AND IMPLICATIONS The anti-osteoclastogenic effects of 2-MS could reflect the block of RANKL-induced association of TRAF6-TAK1 complexes with consequent decrease of IkappaB-mediated NF-kappaB and mitogen-activated protein kinases-mediated c-Fos activation pathways and suppression of NFATc1 and other gene expression, essential for bone resorption.
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Popova M, Chen CN, Chen PY, Huang CY, Bankova V. A validated spectrophotometric method for quantification of prenylated flavanones in pacific propolis from Taiwan. PHYTOCHEMICAL ANALYSIS : PCA 2010; 21:186-91. [PMID: 19856482 DOI: 10.1002/pca.1176] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
INTRODUCTION Because of its chemical diversity, the only way to standardise propolis is to specify multiple standards for different propolis types according to the corresponding chemical profile. So far, this has been done only for European propolis. OBJECTIVE To develop a rapid low-cost spectrophotometric procedure for quantification of bioactive prenylated flavanones in Taiwanese propolis. METHODOLOGY The proposed method quantifies the total flavanones on the basis of their absorption as coloured phenylhydrazones formed by interaction with 2,4-dinitrophenylhydrazine. The procedure was validated through model mixture of compounds representing the composition of Taiwanese propolis according to previous studies. The major flavanones of the propolis samples (propolins C, D, F and G) were quantified by HPLC. Antiradical activity against DPPH was also measured. The DNP (dinitrophenylhydrazine) spectrophotometric method is applied for the first time for quantification of prenylated flavanones. RESULTS Spectophotometric procedure applicable to new type propolis (Macaranga type) was developed with recovery between 105 and 110% at the concentration range of 0.573-1.791 mg/mL. Six propolis samples were analysed by spectrophotometry using the procedure developed and validated, and by HPLC as the results demonstrated satisfactory agreement. Neither the spectrophotometric data nor the values measured by HPLC showed significant correlation with the antiradical activity against DPPH. CONCLUSION The proposed spectrophotometric procedure is useful for routine analyses of Macaranga-type propolis, because of its simplicity, repeatability and acceptable accuracy. Its application to a number of commercial samples could be used as a basis for standardisation and quality control of Pacific propolis.
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Huang WJ, Wu CL, Lin CW, Chi LL, Chen PY, Chiu CJ, Huang CY, Chen CN. Marchantin A, a cyclic bis(bibenzyl ether), isolated from the liverwort Marchantia emarginata subsp. tosana induces apoptosis in human MCF-7 breast cancer cells. Cancer Lett 2009; 291:108-19. [PMID: 19913353 DOI: 10.1016/j.canlet.2009.10.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Revised: 10/03/2009] [Accepted: 10/09/2009] [Indexed: 12/20/2022]
Abstract
Liverwort constituents have been reported to exert a broad spectrum of biological activities. In this study, we used a bioactivity-guided separation of an extract from the liverwort species Marchantia emarginata subsp. tosana to determine its anticancer activity. A high level of the active ingredient was isolated from this liverwort and its chemical structure was identified and characterized by various spectra. It was found to be identical to a well-known compound, marchantin A, a cyclic bisbibenzyl ether. However, no anticancer activities of this compound have previously been reported. We found that marchantin A efficiently induced cell growth inhibition in human MCF-7 breast cancer cells, with an IC(50) of 4.0microg/mL. Fluorescence microscopy and a Western blot analysis indicated that marchantin A actively induced apoptosis of MCF-7 cells. The levels of cleaved caspase-8, cleaved caspase-3, cleaved caspase-9, and cleaved poly (ADP ribose) polymerase (PARP) increased. However, the level of Bid markedly decreased in a dose- and time-dependent manner. We also evaluated the anticancer activities of marchantin A on the regulation of cell cycle regulators such as p21, p27, cyclin B1, and cyclin D1. The p21 and p27 gene expressions increased markedly while cyclin B1 and D1 gene expression decreased markedly by treatment with marchantin A. Many report demonstrated that liverwort was suggested to possess potent antioxidant activity. Our results indicate that marchantin A possesses free radical-scavenging activity (EC(50)=20microg/mL). Taken together, for the first time, the compound marchantin A from liverworts demonstrated to be a potent inducer of apoptosis in MCF-7 cells.
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Cheung CM, Tsoi TH, Hon SFK, Au-Yeung M, Shiu KL, Lee CN, Huang CY. Using the National Institutes of Health Stroke Scale (NIHSS) to predict the mortality and outcome of patients with intracerebral haemorrhage. Hong Kong Med J 2008; 14:367-370. [PMID: 18840907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
Abstract
OBJECTIVES To investigate whether the National Institutes of Health Stroke Scale (NIHSS) can be used to predict mortality and functional outcome in patients presenting with intracerebral haemorrhage. DESIGN Retrospective study of a prospectively collected cohort. SETTING Regional hospital, Hong Kong. PATIENTS A cohort of 359 patients presented to our hospital from 1996 to 2001 with their first-ever stroke and intracerebral haemorrhage. MAIN OUTCOME MEASURES The sensitivity and specificity of the NIHSS with a cut-off point of 20 in predicting mortality at 30 days and 5 years, and a favourable functional outcome at 5 years. RESULTS A total of 359 patients were available for analysis and were divided into three subgroups according to the site and the size of the haematoma. The NIHSS can predict 30-day mortality with a sensitivity of 81% [corrected] and a specificity of 90% [corrected] The NIHSS can predict 5-year mortality with a sensitivity of 57% [corrected] and a specificity of 92% [corrected] In predicting favourable functional outcomes at 5 years, the NIHSS had a sensitivity of 98% [corrected] and a specificity of 16% [corrected] CONCLUSIONS The NIHSS performed on admission can be used to predict mortality at 30 days and 5 years as well as favourable functional outcome at 5 years, all with an acceptable sensitivity and specificity.
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Tsai JH, Liu JY, Wu TT, Ho PC, Huang CY, Shyu JC, Hsieh YS, Tsai CC, Liu YC. Effects of silymarin on the resolution of liver fibrosis induced by carbon tetrachloride in rats. J Viral Hepat 2008; 15:508-14. [PMID: 18397225 DOI: 10.1111/j.1365-2893.2008.00971.x] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Silymarin, a standardized extract of the milk thistle (Silybum marianum), has a long tradition as a herbal remedy, and was introduced as a hepatoprotective agent a few years ago. However, the therapeutic effects of silymarin remain undefined. Carbon tetrachloride (CCl4) is a xenobiotic used extensively to induce oxidative stress and is one of the most widely used hepatic toxins for experimental induction of liver fibrosis in the laboratory. In this study, we investigated the restoration of the CCl4-induced hepatic fibrosis by high dose of silymarin in rats. After treatment with oil (as normal group; n = 6) or CCl4 [as model (n = 7) and therapeutic (n = 7) groups] by intragastric delivery for 8 weeks for the induction of liver fibrosis, the rats in the normal and model group were administered orally normal saline four times a week for 3 weeks whilst the therapeutic group received silymarin (200 mg/kg). The histopathological changes were observed with Masson staining. The results showed that the restoration of the CCl4-induced damage of liver fibrosis in the therapeutic group was significantly increased as compared to that in the model group. Moreover, silymarin significantly decreased the elevation of aspartate aminotransferase (AST), alanine aminotransferase, and alkaline phosphatase in serum, and also reversed the altered expressions of alpha-smooth muscle actin in liver tissue. Therefore, these findings indicated that silymarin may have the potential to increase the resolution of the CCl4-induced liver fibrosis in rats.
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Jiang YN, Wu CY, Huang CY, Chu HP, Ke MW, Kung MS, Li KY, Wang CH, Li SH, Wang Y, Ju YT. Interpopulation and intrapopulation maternal lineage genetics of the Lanyu pig (Sus scrofa) by analysis of mitochondrial cytochrome b and control region sequences. J Anim Sci 2008; 86:2461-70. [PMID: 18344290 DOI: 10.2527/jas.2007-0049] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The Lanyu pig is an indigenous breed from the Lanyu Islet, which is southeast of Taiwan. Two herds of Lanyu pigs were introduced from the Lanyu Islet into Taiwan in 1975 and 1980. The current population of conserved Lanyu pigs consists of only 44 animals with unknown genetic lineage. The Lanyu pig possesses a distinct maternal genetic lineage remote from Asian and European pigs. The present study aimed to understand the phylogenetic relationship among conserved Lanyu, Asian, and European type pigs based on the cytochrome b coding gene, to ascertain the maternal lineage and genetic diversity within the conserved Lanyu pigs, and to address whether genetic introgression from exotic or Formosan wild pigs had occurred in the conserved Lanyu pigs. Entire mitochondrial genomes of both types of Lanyu pig comprised 2 ribosomal RNA, 22 transfer RNA, and 13 protein-coding genes. Only 2 haplotypes of the mitochondrial DNA (mtDNA) control region and cytochrome b were identified in the conserved Lanyu pig herds. When maximum likelihood trees were constructed, the Type I Lanyu mitochondrial genes formed a unique clade with a large pairwise distance of both cytochrome b and the control region from Asian and European type breeds, Formosan wild pigs, and exotic breeds. Significant loss of genetic diversity of mtDNA within the conserved Lanyu pigs was demonstrated by low haplotype and nucleotide diversities, supported by Fu and Li's D* neutrality test (1.44055; P < 0.05). The mtDNA control region sequences of extant pigs in the Lanyu Islet, however, showed high haplotype and nucleotide diversity, and clustered with exotic pigs. These results indicate no maternal lineage mtD-NA gene introgression from Formosan wild pigs and introduced exotic pigs to conserved Type I Lanyu pigs, and a severe loss of heterozygosity of mtDNA in conserved Lanyu pigs. The remaining extant pigs on the Lanyu Islet have been introgressed with exotic breeds. Strategies for future conservation of native Lanyu pigs are now even more urgent and important.
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Cheng SF, Chang JH, Huang CY. Particle separation to enhance the efficiency of soil acid washing--case study on the removal of cadmium from contaminated soil in southwestern Taiwan. ENVIRONMENTAL TECHNOLOGY 2007; 28:1163-1171. [PMID: 17970523 DOI: 10.1080/09593332808618877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The current trend in remediating contaminated soil by acid washing is to separate the soil mass by their particles sizes prior to washing. However, there is little information about the cost-effectiveness of this practice in literature. In this research, a cadmium-contaminated agricultural field has been selected for conducting a comparative study on cadmium removal by applying the acid washing method to soil samples with and without prior particle separation. The study provides valuable information for the advancement of this method to remediate contaminated soil. The results indicate that sand particles constitute about 70% of the total soil mass but only 24% of the total cadmium. After acid washing once, less than 2% of cadmium remains; multiple washing of the sand portion is thus not cost-effective. Furthermore, after particle separation, the soil mass that needs to be washed is greatly reduced to 35%; the total cost is reduced by about one third due to the savings in the acid solution utilization and the treatment of used acid solution.
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Huang WJ, Huang CH, Wu CL, Lin JK, Chen YW, Lin CL, Chuang SE, Huang CY, Chen CN. Propolin G, a prenylflavanone, isolated from Taiwanese propolis, induces caspase-dependent apoptosis in brain cancer cells. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2007; 55:7366-76. [PMID: 17685631 DOI: 10.1021/jf0710579] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
We have previously shown that six propolins, A-F, could be isolated from Taiwanese propolis (TP) and that they exerted a broad spectrum of biological activities. Recently, we isolated a seventh compound, propolin G. Its chemical structure has been identified by NMR and fast atom bombardment-mass spectrometry spectra and was found to be identical to a known compound, nymphaeol C. We used high-performance liquid chromatography to determine the relative contents of propolins C, D, F, and G in TP collected in various seasons and regions and found them to be relatively higher in TPs collected from May to July than from September to October. In our present study, we were interested in the various biological activities of TP extract as well as in propolin G as a pure compound. We found that propolin G could efficiently induce apoptosis in brain cancer cell lines (glioma and glioblastoma). The apoptosis might have been through a mitochondrial- and caspase-dependent pathway. This result demonstrated that the TP collection season was more an important factor than the geographical region. Propolis has been suggested to possess a potent antioxidant activity. We further evaluated the antioxidant property of propolin G using DPPH (1,2-diphenyl-2-picryhydrazyl). Our results indicate that propolin G does possess free radical scavenging activity. We also evaluated the neuroprotective action of propolin G, TP, and BP (Brazilian propolis) extracts against oxidative stress in rat primary cortical neurons. Our data demonstrate that propolin G and TP extracts have a marked neuroprotective effect that is greater than BP extract. In conclusion, the isolation and characterization of propolin G from TP have demonstrated for the first time that this compound is a potent inducer of apoptosis in brain cancer cells and that this compound and TP extract exhibit a protective effect against oxidative stress in rat cortical neurons.
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